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  1. ALMA News

    NASA Astrophysics Data System (ADS)

    Wilson, T.

    2005-06-01

    SCIENCE ADVISORY COMMITTEE REPORT The European ALMA Science Advisory Committee (ESAC) met on 23 February 2005 at ESO in Garching. On the two following days, the ALMA Science Advisory Committee (ASAC) met. In both meetings the discussions were mostly concerned with a request by the ALMA Board to consider the impact of ‘rebaselining' proposals on the science that can be done with ALMA. Much of the need for rebaselining is caused by the large increases in commodity prices, such as those of steel and oil. These have led to large cost increases for ALMA. A number of possible options for savings were proposed.

  2. ALMA measures Calama earthquake

    NASA Astrophysics Data System (ADS)

    Brito, R.; Shillue, B.

    2010-04-01

    On 4 March 2010, the ALMA system response to an extraordinarily large disturbance was measured when a magnitude 6.3 earthquake struck near Calama, Chile, relatively close to the ALMA site. Figures 1 through 4 demonstrate the remarkable performance of the ALMA system to a huge disturbance that was more than 100 times the specification for correction accuracy.

  3. ALMA Pipeline: Current Status

    NASA Astrophysics Data System (ADS)

    Shinnaga, H.; Humphreys, E.; Indebetouw, R.; Villard, E.; Kern, J.; Davis, L.; Miura, R. E.; Nakazato, T.; Sugimoto, K.; Kosugi, G.; Akiyama, E.; Muders, D.; Wyrowski, F.; Williams, S.; Lightfoot, J.; Kent, B.; Momjian, E.; Hunter, T.; ALMA Pipeline Team

    2015-12-01

    The ALMA Pipeline is the automated data reduction tool that runs on ALMA data. Current version of the ALMA pipeline produces science quality data products for standard interferometric observing modes up to calibration process. The ALMA Pipeline is comprised of (1) heuristics in the form of Python scripts that select the best processing parameters, and (2) contexts that are given for book-keeping purpose of data processes. The ALMA Pipeline produces a "weblog" that showcases detailed plots for users to judge how each step of calibration processes are treated. The ALMA Interferometric Pipeline was conditionally accepted in March 2014 by processing Cycle 0 and Cycle 1 data sets. From Cycle 2, ALMA Pipeline is used for ALMA data reduction and quality assurance for the projects whose observing modes are supported by the ALMA Pipeline. Pipeline tasks are available based on CASA version 4.2.2, and the first public pipeline release called CASA 4.2.2-pipe has been available since October 2014. One can reduce ALMA data both by CASA tasks as well as by pipeline tasks by using CASA version 4.2.2-pipe.

  4. ALMA science operations

    NASA Astrophysics Data System (ADS)

    Nyman, Lars-Åke; Andreani, Paola; Hibbard, John; Okumura, Sachiko K.

    2010-07-01

    The ALMA (Atacama Large Millimeter/submillimeter Array) project is an international collaboration between Europe, East Asia and North America in cooperation with the Republic of Chile. The ALMA Array Operations Site (AOS) is located at Chajnantor, a plateau at an altitude of 5000 m in the Atacama desert in Chile, and the ALMA Operations Support Facility (OSF) is located near the AOS at an altitude of 2900 m. ALMA will consist of an array of 66 antennas, with baselines up to 16 km and state-of-the-art receivers that cover all the atmospheric windows up to 1 THz. An important component of ALMA is the compact array of twelwe 7-m and four 12-m antennas (the Atacama Compact Array, ACA), which will greatly enhance ALMA's ability to image extended sources. Construction of ALMA started in 2003 and will be completed in 2013. Commissioning started in January 2010 and Early Science Operations is expected to start during the second half of 2011. ALMA science operations is provided by the Joint ALMA Observatory (JAO) in Chile, and the three ALMA Regional Centers (ARCs) located in each ALMA region - Europe, North America and East Asia. ALMA observations will take place 24h per day, interrupted by maintenance periods, and will be done in service observing mode with flexible (dynamic) scheduling. The observations are executed in the form of scheduling blocks (SBs), each of which contains all information necessary to schedule and execute the observations. The default output to the astronomer will be pipeline-reduced images calibrated according to the calibration plan. The JAO is responsible for the data product quality. All science and calibration raw data are captured and archived in the ALMA archive, a distributed system with nodes at the OSF, the Santiago central office and the ARCs. Observation preparation will follow a Phase 1/Phase 2 process. During Phase 1, observation proposals will be created using software tools provided by the JAO and submitted for scientific and

  5. ALMA Pipeline Heuristics

    NASA Astrophysics Data System (ADS)

    Lightfoot, J.; Wyrowski, F.; Muders, D.; Boone, F.; Davis, L.; Shepherd, D.; Wilson, C.

    2006-07-01

    The ALMA (Atacama Large Millimeter Array) Pipeline Heuristics system is being developed to automatically reduce data taken with the standard observing modes. The goal is to make ALMA user-friendly to astronomers who are not experts in radio interferometry. The Pipeline Heuristics system must capture the expert knowledge required to provide data products that can be used without further processing. Observing modes to be processed by the system include single field interferometry, mosaics and single dish `on-the-fly' maps, and combinations of these modes. The data will be produced by the main ALMA array, the ALMA Compact Array (ACA) and single dish antennas. The Pipeline Heuristics system is being developed as a set of Python scripts. For interferometry these use as data processing engines the CASA/AIPS++ libraries and their bindings as CORBA objects within the ALMA Common Software (ACS). Initial development has used VLA and Plateau de Bure data sets to build and test a heuristic script capable of reducing single field data. In this paper we describe the reduction datapath and the algorithms used at each stage. Test results are presented. The path for future development is outlined.

  6. ACS: ALMA Common Software

    NASA Astrophysics Data System (ADS)

    Chiozzi, Gianluca; Šekoranja, Matej

    2013-02-01

    ALMA Common Software (ACS) provides a software infrastructure common to all ALMA partners and consists of a documented collection of common patterns and components which implement those patterns. The heart of ACS is based on a distributed Component-Container model, with ACS Components implemented as CORBA objects in any of the supported programming languages. ACS provides common CORBA-based services such as logging, error and alarm management, configuration database and lifecycle management. Although designed for ALMA, ACS can and is being used in other control systems and distributed software projects, since it implements proven design patterns using state of the art, reliable technology. It also allows, through the use of well-known standard constructs and components, that other team members whom are not authors of ACS easily understand the architecture of software modules, making maintenance affordable even on a very large project.

  7. A Roof for ALMA

    NASA Astrophysics Data System (ADS)

    2007-03-01

    On 10 March, an official ceremony took place on the 2,900m high site of the Atacama Large Millimeter/submillimeter Array (ALMA) Operations Support Facility, from where the ALMA antennas will be remotely controlled. The ceremony marked the completion of the structural works, while the building itself will be finished by the end of the year. This will become the operational centre of one of the most important ground-based astronomical facilities on Earth. ESO PR Photo 13a/07 ESO PR Photo 13a/07 Cutting the Red Ribbon The ceremony, known as 'Tijerales' in Chile, is the equivalent to the 'roof-topping ceremony' that takes place worldwide, in one form or another, to celebrate reaching the highest level of a construction. It this case, the construction is the unique ALMA Operations Support Facility (OSF), located near the town of San Pedro de Atacama. "The end of this first stage represents an historic moment for ALMA," said Hans Rykaczewski, the European ALMA Project Manager. "Once completed in December 2007, this monumental building of 7,000 square metres will be one of the largest and most important astronomical operation centres in the world." ALMA, located at an elevation of 5,000m in the Atacama Desert of northern Chile, will provide astronomers with the world's most advanced tool for exploring the Universe at millimetre and submillimetre wavelengths. ALMA will detect fainter objects and be able to produce much higher-quality images at these wavelengths than any previous telescope system. The OSF buildings are designed to suit the requirements of this exceptional observatory in a remote, desert location. The facility, which will host about 100 people during operations, consists of three main buildings: the technical building, hosting the control centre of the observatory, the antenna assembly building, including four antenna foundations for testing and maintenance purposes, and the warehouse building, including mechanical workshops. Further secondary buildings are

  8. The ALMA antenna procurement

    NASA Astrophysics Data System (ADS)

    Stanghellini, S.; Zivick, Jeff; Inatani, Junji

    2009-10-01

    Visitors who come to the OSF at regular intervals find a growing population of antennas at various stages of assembly and testing. The long path from the start of the definition of antenna specifications to the start of science operations with the antennas was and still is a formidable endeavor. When completed, ALMA will comprise a 12-meter diameter antennas array, the bilateral interferometer array, of a minimum of fifty antennas and in addition, the ACA (Atacama Compact Array), composed of four 12-meter diameter antennas and twelve 7-meter diameter antennas. Out of the fifty antennas of the bilateral interferometer array, one-half are provided by the North American partners of ALMA, the other half by the European partners. The sixteen antennas that will comprise the ACA are provided by the East Asian Partners of ALMA. Here we review some key points of this challenging process and we provide a brief history and status of the ALMA antennas. Because of the length of the description, we will present this in a series of two articles. In this first part we concentrate mostly on the bilateral antenna procurement. A detailed description of the ACA will be presented in the next newsletter.

  9. Alma Data Mining Toolkit

    NASA Astrophysics Data System (ADS)

    Friedel, Douglas; Looney, Leslie; Teuben, Peter J.; Pound, Marc W.; Rauch, Kevin P.; Mundy, Lee; Harris, Robert J.; Xu, Lisa

    2016-06-01

    ADMIT (ALMA Data Mining Toolkit) is a Python based pipeline toolkit for the creation and analysis of new science products from ALMA data. ADMIT quickly provides users with a detailed overview of their science products, for example: line identifications, line 'cutout' cubes, moment maps, and emission type analysis (e.g., feature detection). Users can download the small ADMIT pipeline product (< 20MB), analyze the results, then fine-tune and re-run the ADMIT pipeline (or any part thereof) on their own machines and interactively inspect the results. ADMIT has both a web browser and command line interface available for this purpose. By analyzing multiple data cubes simultaneously, data mining between many astronomical sources and line transitions are possible. Users are also able to enhance the capabilities of ADMIT by creating customized ADMIT tasks satisfying any special processing needs. We will present some of the salient features of ADMIT and example use cases.

  10. ALMA's Science Archive

    NASA Astrophysics Data System (ADS)

    Lacy, Mark

    2011-05-01

    The Atacama Large Mm/submm Array (ALMA) will begin Early Science Operations in the Fall of 2011. The science archive will have an estimated growth rate of 200TB/year. Besides raw data, the archive will store pipeline processed images and data cubes. I will discuss some of the plans for data storage, access and dissemination, and how we plan to link data and journal articles.

  11. ALMA correlator computer systems

    NASA Astrophysics Data System (ADS)

    Pisano, Jim; Amestica, Rodrigo; Perez, Jesus

    2004-09-01

    We present a design for the computer systems which control, configure, and monitor the Atacama Large Millimeter Array (ALMA) correlator and process its output. Two distinct computer systems implement this functionality: a rack- mounted PC controls and monitors the correlator, and a cluster of 17 PCs process the correlator output into raw spectral results. The correlator computer systems interface to other ALMA computers via gigabit Ethernet networks utilizing CORBA and raw socket connections. ALMA Common Software provides the software infrastructure for this distributed computer environment. The control computer interfaces to the correlator via multiple CAN busses and the data processing computer cluster interfaces to the correlator via sixteen dedicated high speed data ports. An independent array-wide hardware timing bus connects to the computer systems and the correlator hardware ensuring synchronous behavior and imposing hard deadlines on the control and data processor computers. An aggregate correlator output of 1 gigabyte per second with 16 millisecond periods and computational data rates of approximately 1 billion floating point operations per second define other hard deadlines for the data processing computer cluster.

  12. ALMA Observations of TNOs

    NASA Astrophysics Data System (ADS)

    Butler, Bryan J.; Brown, Michael E.

    2016-10-01

    Some of the most fundamental properties of TNOs are still quite poorly constrained, including diameter and density. Observations at long thermal wavelengths, in the millimeter and submillimeter, hold promise for determining these quantities, at least for the largest of these bodies (and notably for those with companions). Knowing this information can then yield clues as to the formation mechanism of these bodies, allowing us to distinguish between pairwise accretion and other formation scenarios.We have used the Atacama Large Millimeter/Submillimeter Array (ALMA) to observe Orcus, Quaoar, Salacia, and 2002 UX25 at wavelengths of 1.3 and 0.8 mm, in order to constrain the sizes of these bodies. We have also used ALMA to make astrometric observations of the Eris-Dysnomia system, in an attempt to measure the wobble of Eris and hence accurately determine its density. Dysnomia should also be directly detectable in those data, separate from Eris (ALMA has sufficient resolution in the configuration in which the observations were made). Results from these observations will be presented and discussed.

  13. The ALMA Software System

    NASA Astrophysics Data System (ADS)

    Schwarz, J.; Sommer, H.; Farris, A.

    2004-07-01

    Prospective users, instrumentation and location of the Atacama Large Millimeter Array (ALMA) all present its software developers with major challenges. The development of this software will be distributed among many institutes on two continents, mimicking the software itself, which will have to function in a distributed environment, spanning the 0.5-10 km baselines between antennas, as well as the much larger distances that will separate the array site at the 5000m-high Llano de Chajnantor, the Operations Support Facility in San Pedro de Atacama, the Santiago Central Office, and the ALMA Regional Centers in North America and Europe. To make distributed development successful, we have defined interfaces that allow separated groups to work independently of their counterparts at other locations as much as possible. We have defined a common architecture and infrastructure, so that work done at one location is not unnecessarily duplicated at another, and that similar tasks are done in a similar way throughout the project. A single, integrated Archive attends to the needs of all subsystems for persistent storage, and hides details of the underlying database technology. The separation of functional from technical concerns is built into the system architecture through the use of the Container-Component model: application developers can concentrate on implementing functionality in runtime-deployable components, which in turn depend on Containers to provide them with services such as access to remote resources, transparent serialization of value objects to XML, logging, error-handling and security. The resulting middleware, which forms part of the ALMA Common Software (ACS), is based on CORBA and XML.

  14. The ALMA software architecture

    NASA Astrophysics Data System (ADS)

    Schwarz, Joseph; Farris, Allen; Sommer, Heiko

    2004-09-01

    The software for the Atacama Large Millimeter Array (ALMA) is being developed by many institutes on two continents. The software itself will function in a distributed environment, from the 0.5-14 kmbaselines that separate antennas to the larger distances that separate the array site at the Llano de Chajnantor in Chile from the operations and user support facilities in Chile, North America and Europe. Distributed development demands 1) interfaces that allow separated groups to work with minimal dependence on their counterparts at other locations; and 2) a common architecture to minimize duplication and ensure that developers can always perform similar tasks in a similar way. The Container/Component model provides a blueprint for the separation of functional from technical concerns: application developers concentrate on implementing functionality in Components, which depend on Containers to provide them with services such as access to remote resources, transparent serialization of entity objects to XML, logging, error handling and security. Early system integrations have verified that this architecture is sound and that developers can successfully exploit its features. The Containers and their services are provided by a system-orienteddevelopment team as part of the ALMA Common Software (ACS), middleware that is based on CORBA.

  15. ALMA from the Users' Perspective

    NASA Astrophysics Data System (ADS)

    Johnson, Kelsey

    2010-05-01

    After decades of dreaming and preparation, the call for early science with ALMA is just around the corner. The goal of this talk is to illustrate the process of preparing and carrying out a research program with ALMA. This presentation will step through the user interface for proposal preparation, proposal review, project tracking, data acquisition, and post-processing. Examples of the software tools, including the simulator and spectral line catalog, will be included.

  16. From Virgil to Alma Mater

    ERIC Educational Resources Information Center

    Spitz, Ellen Handler

    2007-01-01

    For a college to become an alma mater in the hearts of its students, it must show, true to the Latin meaning, the wisdom and comfort of a good foster mother. Since "alma mater" is Latin, and since the study of Latin has waned on all educational levels in both pious and secular milieus, the author wonders whether folks who use that term really know…

  17. Taming the ALMA Data Avalanche

    NASA Astrophysics Data System (ADS)

    Stoehr, Felix

    2015-03-01

    The Atacama Large Millimeter/submillimeter Array (ALMA) is nearing its phase of full operations. ALMA will collect about 200TB/year of astronomical data which will be reduced by an automatic pipeline and turned into fully calibrated science-ready data products. We present design choices, challenges and solutions from data capturing over data reduction and data distribution to archival research, that allow to deal with the large amounts of data and, hopefully, achieve the maximum amount of science return.

  18. ALMA telescope reaches new heights

    NASA Astrophysics Data System (ADS)

    2009-09-01

    The ALMA (Atacama Large Millimeter/submillimeter Array) astronomical observatory has taken another step forward - and upwards. One of its state-of-the-art antennas was carried for the first time to the 5000m plateau of Chajnantor, in the Chilean Andes, on the back of a custom-built giant transporter. The antenna, which weighs about 100 tons and has a diameter of 12 metres, was transported up to the high-altitude Array Operations Site, where the extremely dry and rarefied air is ideal for ALMA's observations of the Universe. The conditions at the Array Operations Site on Chajnantor, while excellent for astronomy, are also very harsh. Only half as much oxygen is available as at sea level, making it very difficult to work there. This is why ALMA's antennas are assembled and tested at the lower 2900 m altitude of the ALMA Operations Support Facility. It was from this relatively hospitable base camp that the ALMA antenna began its journey to the high Chajnantor site. "This is an important moment for ALMA. We are very happy that the first transport of an antenna to the high site went flawlessly. This achievement was only possible through contributions from all international ALMA partners: this particular antenna is provided by Japan, the heavy-lift transporter by Europe, and the receiving electronics inside the antenna by North America, Europe, and Asia", said Wolfgang Wild, European ALMA Project Manager. The trip began when one of the two ALMA transporters, named Otto, lifted the antenna onto its back. It then carried its heavy load along the 28 km road from the Operations Support Facility up to the Array Operations Site. While the transporter is capable of speeds of up to 12 km/hour when carrying an antenna, this first journey was made more slowly to ensure that everything worked as expected, taking about seven hours. The ALMA antennas are the most advanced submillimetre-wavelength antennas ever made. They are designed to operate fully exposed in the harsh conditions

  19. Solar System Science with ALMA

    NASA Astrophysics Data System (ADS)

    Butler, Bryan J.; Gurwell, Mark A.

    1999-10-01

    Observations of solar system bodies with the ALMA array will undoubtedly allow significant progress to be made on our understanding of the individual bodies therein, their interactions, and possibly their formation. With its fantastic resolution, sensitivity, and speed, ALMA will be one of the most important ground based observatories for planetary science. While it is nearly impossible to predict what will be learned about the solar system and its bodies, we can predict some general areas where we expect that ALMA will make significant contributions. We will concentrate here on 2 such areas: observations of small bodies, and observations of the solid surfaces of the larger bodies. Small bodies Observations of comets will help disentangle the story of their formation and history, and shed light on the physical processes occuring in their atmospheres. Observations of NEAs by ALMA will contribute to knowledge of their properties and orbits (ALMA can observe in daytime). Observations of KBOs will help to determine their properties and origin. Larger bodies We imagine that observations of Mercury, Mars, the larger asteroids, the moons of Jupiter, Saturn, Uranus, and Neptune, and the Pluto/Charon will be undertaken to determine properties and physical processes of their surfaces and subsurfaces.

  20. ALMA Telescope Reaches New Heights

    NASA Astrophysics Data System (ADS)

    2009-09-01

    The ALMA (Atacama Large Millimeter/submillimeter Array) astronomical observatory took another step forward and upward, as one of its state-of-the-art antennas was carried for the first time to Chile's 16,500-foot-high plateau of Chajnantor on the back of a giant, custom-built transporter. The 40-foot-diameter antenna, weighing about 100 tons, was moved to ALMA's high-altitude Array Operations Site, where the extremely dry and rarefied air is ideal for observing the Universe. The conditions at the Array Operations Site on Chajnantor, while excellent for astronomy, are also very harsh. Only about half as much oxygen is available as at sea level, making it very difficult to work there. This is why ALMA's antennas are assembled and tested at the lower 9,500-foot altitude of the ALMA Operations Support Facility (OSF). It was from this relatively hospitable base camp that the ALMA antenna began its journey to the high Chajnantor site. "The successful transport of the first ALMA Antenna to the high site marks the start of the next phase of the project. Now that we are starting to move the ALMA antennas to the high site, the real work begins and the exciting part is just beginning," said Adrian Russell, North American ALMA Project Manager. The antenna's trip began when one of the two ALMA transporters lifted the antenna onto its back, carrying its heavy load along the 17-mile road from the Operations Support Facility up to the Array Operations Site. While the transporter is capable of speeds of up to 8 miles per hour when carrying an antenna, this first journey was made more slowly to ensure that everything worked as expected, taking about seven hours. The ALMA antennas use state-of-the-art technology, and are the most advanced submillimeter-wavelength antennas ever made. They are designed to operate fully exposed in the harsh conditions of the Array Operations Site, to survive strong winds and extreme temperatures, to point precisely enough that they could pick out a golf

  1. ALMA Cycle 0 Publication Statistics

    NASA Astrophysics Data System (ADS)

    Stoehr, F.; Grothkopf, U.; Meakins, S.; Bishop, M.; Uchida, A.; Testi, L.; Iono, D.; Tatematsu, K.; Wootten, A.

    2015-12-01

    The scientific impact of a facility is the most important measure of its success. Monitoring and analysing the scientific return can help to modify and optimise operations and adapt to the changing needs of scientific research. The methodology that we have developed to monitor the scientific productivity of the ALMA Observatory, as well as the first results, are described. We focus on the outcome of the first cycle (Cycle 0) of ALMA Early Science operations. Despite the fact that only two years have passed since the completion of Cycle 0 and operations have already changed substantially, this analysis confirms the effectiveness of the underlying concepts. We find that ALMA is fulfilling its promise as a transformational facility for the observation of the Universe in the submillimetre.

  2. ALMA Common Software - UTFSM Group

    NASA Astrophysics Data System (ADS)

    Araya, M.; Avarias, J.; Mora, M.; Tobar, R.

    The ACS-UTFSM Group was created as a distributed systems research team on astronomical and non-astronomical applications on the year 2004. The choice of the ALMA Common Software framework (ACS) as the development platform came from the experience gained during summerjobs at ESO observatories. After three years of informal contributions to ACS development, the team presented a technology exchange initiative to the ALMA-CONICYT Fund 2006, which was granted in 2007. Through the past years, the UTFSM helped the ACS team with "nice-to-have" applications and testing. Currently the ACS-UTFSM is involved in several contributions to ACS, and the development of a flexible telescope control system (gTCS) framework which aims to encapsulate common requirements and will provide a uniform software. In preparation for this challenging objective, several small projects are currently being developed. The other interesting edge of the team work is the technology transfer initiatives. Several inter-universities collaborations are flourishing (PUC, UCN, UV) after the first ACS Workshop held at the UTFSM this year. Today three former team members are working at NRAO's ALMA Test Facility in Socorro, New Mexico. Two other students will have a summer job next year to work in ALMA related development.

  3. The North American ALMA Science Center

    NASA Astrophysics Data System (ADS)

    Lonsdale, Carol J.; Hibbard, J. E.; Staff, NAASC

    2010-01-01

    The North American ALMA Science Center at the National Radio Astronomy Observatory, NRAO, in Charlottesville, Virginia, in partnership with the Herzberg Institute of Astrophysics in Victoria, Canada, will support the North American community in their observations with the Atacama Large Millimeter Array, ALMA. Our goal is to promote successful observations with ALMA for both novice users, with no experience in either interferometry or millimeter astronomy, and experts alike. We will describe the services that the Science Center will provide for the community, from education about the capabilities of ALMA, though proposal preparation to data analysis. The Science Center will host a website with a Helpdesk that includes FAQs and a growing knowledgebase of ALMA expertise, and will support extensive demos and tutorials on observation preparation and data reduction with ALMA. The Science Center also promotes science-themed meetings. The staff of the Science Center will provide expert assistance for observers at all stages of development and execution of their program. There are visitor and postdoc opportunities at the Science Center. The North American ALMA Science Center is one of three regional centers around the globe that will support ALMA observations. Our partners are the European ALMA Regional Center at ESO in Garching, Germany, and the East Asian ALMA Region Center in Tokyo, Japan.

  4. A Look Inside Hurricane Alma

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Hurricane season in the eastern Pacific started off with a whimper late last month as Alma, a Category 2 hurricane, slowly made its way up the coast of Baja California, packing sustained winds of 110 miles per hour and gusts of 135 miles per hour. The above image of the hurricane was acquired on May 29, 2002, and displays the rainfall rates occurring within the storm. Click the image above to see an animated data visualization (3.8 MB) of the interior of Hurricane Alma. The images of the clouds seen at the beginning of the movie were retrieved from the National Oceanic and Atmospheric Association's (NOAA's) Geostationary Orbiting Environmental Satellite (GOES) network. As the movie continues, the clouds are peeled away to reveal an image of rainfall levels in the hurricane. The rainfall data were obtained by the Precipitation Radar aboard NASA's Tropical Rainfall Measuring Mission (TRMM) satellite. The Precipitation Radar bounces radio waves off of clouds to retrieve a reading of the number of large, rain-sized droplets within the clouds. Using these data, scientists can tell how much precipitation is occurring within and beneath a hurricane. In the movie, yellow denotes areas where 0.5 inches of rain is falling per hour, green denotes 1 inch per hour, and red denotes over 2 inches per hour. (Please note that high resolution still images of Hurricane Alma are available in the NASA Visible Earth in TIFF format.) Image and animation courtesy Lori Perkins, NASA Goddard Space Flight Center Scientific Visualization Studio

  5. The ALMA Telescope Control System

    NASA Astrophysics Data System (ADS)

    Farris, A.; Marson, Ralph; Kern, Jeff

    2005-10-01

    The Atacama Large Millimeter Array (ALMA) is a joint project between North America, Europe and Japan. ALMA is an aperture synthesis radio telescope consisting of 50 12-meter antennas located at an elevation of 5,000 meters in Llano de Chajnantor, Chile. These antennas will operate at frequencies ranging from 31.3 GHz to 950 GHz. The antennas can be moved and placed in different configurations, with baselines between the antennas varying from 150 meters to 20 km. The 50 antennas are supplemented by sixteen additional ones, known as the ALMA Compact Array (ACA): 12 7-meter antennas and 4 12-meter antennas. The ALMA control system will consist of over 70 computers separated by distances of over 20 km. Two aspects of the system are apparent: its distributed nature and its need to accurately synchronize events across many computers separated by large distances. In this paper we describe key features of the architecture of the ALMA Control System, focusing on its properties as a distributed system and on the mechanisms employed to achieve its time synchronization goals. This control system is a distributed system that uses the ALMA Common Software (ACS) as a middleware system layered on top of CORBA. The architecture of the control system extensively employs the component/container model in ACS. In addition, the use of CORBA allows us to employ Java in the higher levels of the control system, leaving C++ to the lower time-critical levels. Python as a scripting language is used by astronomers, to craft standard observing programs, and engineers, in a testing and debugging mode. Key to the concept of an aperture synthesis telescope is a special purpose hardware system known as a correlator, responsible for making various delay model corrections and correlating the signals from the antennas. There are two correlators in ALMA, one for the array of 50 antennas and one for the ACA. This entire system operates under a control system that must synchronize events across the

  6. ALMA Band 5 Cartridge Performance

    NASA Astrophysics Data System (ADS)

    Billade, Bhushan; Lapkin, I.; Nystrom, O.; Sundin, E.; Fredrixon, M.; Finger, R.; Rashid, H.; Desmaris, V.; Meledin, D.; Pavolotsky, A.; Belitsky, Victor

    2010-03-01

    Work presented here concerns the design and performance of the ALMA Band 5 cold cartridge, one of the 10 frequency channels of ALMA project, a radio interferometer under construction at Atacama Desert in Chile. The Band 5 cartridge is a dual polarization receiver with the polarization separation performed by orthomode transducer (OMT). For each polarization, Band 5 receiver employs sideband rejection (2SB) scheme based on quadrature layout, with SIS mixers covering 163-211 GHz with 4-8 GHz IF. The LO injection circuitry is integrated with mixer chip and is implemented on the same substrate, resulting in a compact 2SB assembly. Amongst the other ALMA bands, the ALMA Band 5 being the lowest frequency band that uses all cold optics, has the largest mirror. Consequently, ALMA Band 5 mirror along with its support structure leaves very little room for placing OMT, mixers and IF subsystems. The constraints put by the size of cold optics and limited cartridge space, required of us to revise the original 2SB design and adopt a design where all the components like OMT, mixer, IF hybrid, isolators and IF amplifier are directly connected to each other without using any co-ax cables in-between. The IF subsystem uses the space between 4 K and 15 K stage of the cartridge and is thermally connected to 4 K stage. Avoiding co-ax cabling required use of custom designed IF hybrid, furthermore, due to limited cooling capacity at 4 K stage, resistive bias circuitry for the mixers is moved to 15 K stage and the IF hybrid along with an integrated bias-T is implemented using superconducting micro-strip lines. The E-probes for both LO and RF waveguide-to-microstrip transitions are placed perpendicular to the wave direction (back-piece configuration). The RF choke at the end of the probes provides a virtual ground for the RF/LO signal, and the choke is DC grounded to the chassis. The on-chip LO injection is done using a microstrip line directional coupler with slot-line branches in the

  7. ALMA observations of protoplanetary disks

    NASA Astrophysics Data System (ADS)

    Hogerheijde, Michiel

    2015-08-01

    The Universe is filled with planetary systems, as recent detections of exo-planets have shown. Such systems grow out of disks of gas and dust that surround newly formed stars. The ground work for our understanding of the structure, composition, and evolution of such disks has been laid with infrared telescopes in the 1980's, 1990's, and 2000's, as well as with millimeter interferometers operating in the United States, France, and Japan. With the construction of the Atacama Large Millimeter / submillimeter Array, a new era of studying planet-forming disks has started. The unprecedented leap in sensitivity and angular resolution that ALMA offers, has truely revolutionized our understanding of disks. No longer featureless objects consisting of gas and smalll dust, they are now seen to harbor a rich structure and chemistry. The ongoing planet-formation process sculpts many disks into systems of rings and arcs; grains grown to millimeter-sizes collect in high-pressure areas where they could grow out to asteroids or comets or further generations of planets. This wealth of new information directly addresses bottlenecks in our theoretical understanding of planet formation, such as the question how grains can grow past the 'meter-sized' barrier or overcome the 'drift barrier', and how gas and ice evolve together and ultimately determine the elemental compositions of both giant and terrestrial planets. I will review the recent ALMA results on protoplanetary disks, presenting results on individual objects and from the first populations studies. I will conclude with a forward look, on what we might expect from ALMA in this area for the years and decades to come.

  8. Probing Cometary Chemistry with ALMA

    NASA Technical Reports Server (NTRS)

    Milam, Stefanie N.

    2010-01-01

    Comets are considered to bear the record of the primitive Solar nebula as remnants of planetesimals that formed the outer planets. To date there are just over two dozen known cometary species compared to the >150 known interstellar molecules. This is likely due to the challenges posed when attempting to measure the composition of these small bodies. With the significant improvement in sensitivity, ALMA will likely enable the detection of new molecules to help us gain better understanding of the chemical complexity found in comets. This advancement in sensitivity will also assist in the measurement of isotope ratios in various species. These values are imperative for determining the conditions during cometary formation as well as provide insight into ongoing speculations of parent species, the possible delivery of H2O to Earth, and a direct comparison to protostellar disk chemistry. The high angular resolution obtained with ALMA will be capable of resolving any compact distributions or density enhancements in the more extended distribution that may lead to a better understanding of the formation of these species in the outer coma. By studying comet compositions we gain insight into the composition of the early Solar System as well as their astrobiological implications.

  9. ADMIT: The ALMA Data Mining Toolkit

    NASA Astrophysics Data System (ADS)

    Teuben, P.; Pound, M.; Mundy, L.; Rauch, K.; Friedel, D.; Looney, L.; Xu, L.; Kern, J.

    2015-09-01

    ADMIT (ALMA Data Mining ToolkiT), a toolkit for the creation of new science products from ALMA data, is being developed as an ALMA Development Project. It is written in Python and, while specifically targeted for a uniform analysis of the ALMA science products that come out of the ALMA pipeline, it is designed to be generally applicable to (radio) astronomical data. It first provides users with a detailed view of their science products created by ADMIT inside the ALMA pipeline: line identifications, line ‘cutout' cubes, moment maps, emission type analysis (e.g., feature detection). Using descriptor vectors the ALMA data archive is enriched with useful information to make archive data mining possible. Users can also opt to download the (small) ADMIT pipeline product, then fine-tune and re-run the pipeline and inspect their hopefully improved data. By running many projects in a parallel fashion, data mining between many astronomical sources and line transitions will also be possible. Future implementations of ADMIT may include EVLA and other instruments.

  10. ALMA observatory equipped with its first antenna

    NASA Astrophysics Data System (ADS)

    2008-12-01

    High in the Atacama region in northern Chile, one of the world's most advanced telescopes has just passed a major milestone. The first of many state-of-the-art antennas has just been handed over to the Atacama Large Millimeter/submillimeter Array (ALMA) project. ALMA is under construction on the plateau of Chajnantor, at an altitude of 5000 m. The telescope is being built by a global partnership, including ESO as the European partner. ALMA ESO PR Photo 49a/08 ALMA antenna ALMA will initially comprise 66 high precision antennas, with the option to expand in the future. There will be an array of fifty 12-metre antennas, acting together as a single giant telescope, and a compact array composed of 7-metre and 12-metre diameter antennas. With ALMA, astronomers will study the cool Universe -- the molecular gas and tiny dust grains from which stars, planetary systems, galaxies and even life are formed. ALMA will provide new, much-needed insights into the formation of stars and planets, and will reveal distant galaxies in the early Universe, which we see as they were over ten billion years ago. The first 12-metre diameter antenna, built by Mitsubishi Electric Corporation for the National Astronomical Observatory of Japan, one of the ALMA partners, has just been handed over to the observatory. It will shortly be joined by North American and European antennas. "Our Japanese colleagues have produced this state-of-the-art antenna to exacting specifications. We are very excited about the handover because now we can fully equip this antenna for scientific observations," said Thijs de Graauw, ALMA Director. Antennas arriving at the ALMA site undergo a series of tests to ensure that they meet the strict requirements of the telescope. The antennas have surfaces accurate to less than the thickness of a human hair, and can be pointed precisely enough to pick out a golf ball at a distance of 15 km. "ALMA is very important to European astronomers and to ESO, the European partner in

  11. First two ALMA antennas successfully linked

    NASA Astrophysics Data System (ADS)

    2009-05-01

    Scientists and engineers working on the world's largest ground-based astronomical project, the Atacama Large Millimeter/submillimeter Array (ALMA), have achieved another milestone -- the successful linking of two ALMA astronomical antennas, synchronised with a precision of one millionth of a millionth of a second -- to observe the planet Mars. ALMA is under construction by an international partnership in the Chilean Andes. ESO PR Photo 18a/09 The two ALMA antennas On 30 April, the team observed the first "interferometric fringes" of an astronomical source by linking two 12-metre diameter ALMA antennas, together with the other critical parts of the system. Mars was chosen as a suitable target for the observations, which demonstrate ALMA's full hardware functionality and connectivity. This important milestone was achieved at the ALMA Operations Support Facility, high in Chile's Atacama region, at an altitude of 2900 metres. "We're very proud and excited to have made this crucial observation, as it proves that the various hardware components work smoothly together. This brings us another step closer to full operations for ALMA as an astronomical observatory," says Wolfgang Wild, the European ALMA Project Manager. The two antennas used in this test will be part of ALMA's array of 66 giant 12-metre and 7-metre diameter antennas that will observe in unison as a single giant telescope, under construction on the Chajnantor plateau above the Operations Support Facility, at an altitude of 5000 metres. ALMA will operate as an interferometer, capturing millimetre and submillimetre wavelength signals from the sky with multiple antennas, and combining them to create extremely high resolution images, similar to those that would be obtained by a single, giant antenna with a diameter equal to the distance between the antennas used. "This can only be achieved with the perfect synchronisation of the antennas and the electronic equipment: a precision much better than one millionth of

  12. Interstellar Isotopes: Prospects with ALMA

    NASA Technical Reports Server (NTRS)

    Charnley Steven B.

    2010-01-01

    Cold molecular clouds are natural environments for the enrichment of interstellar molecules in the heavy isotopes of H, C, N and O. Anomalously fractionated isotopic material is found in many primitive Solar System objects, such as meteorites and comets, that may trace interstellar matter that was incorporated into the Solar Nebula without undergoing significant processing. Models of the fractionation chemistry of H, C, N and O in dense molecular clouds, particularly in cores where substantial freeze-out of molecules on to dust has occurred, make several predictions that can be tested in the near future by molecular line observations. The range of fractionation ratios expected in different interstellar molecules will be discussed and the capabilities of ALMA for testing these models (e.g. in observing doubly-substituted isotopologues) will be outlined.

  13. Alma: coping with culture, poverty, and disability.

    PubMed

    Blanche, E I

    1996-04-01

    This article raises questions about the ways culture affects the nature of health care services. By examining the life story of Alma, a Central American woman who has a daughter with disabilities; her interactions with health care providers; and my own assumptions about cultural differences, I note the impact of cultural differences on coping and adaptation in Alma and in the health care system when working with poor, non-English-speaking clients.

  14. ALMA Observatory Equipped with its First Antenna

    NASA Astrophysics Data System (ADS)

    2008-12-01

    High in the Atacama region of northern Chile one of the world’s most advanced telescopes has just passed a major milestone. The first of many state-of-the-art antennas has been handed over to the Atacama Large Millimeter/submillimeter Array (ALMA) project. ALMA is being built by a global partnership whose North American partners are led by the National Radio Astronomy Observatory (NRAO). With ALMA, astronomers will study the cool Universe, the molecular gas and tiny dust grains from which stars, planetary systems, galaxies and even life are formed. ALMA will provide new, much-needed insights into the formation of stars and planets, and will reveal distant galaxies in the early Universe, which we see as they were over ten billion years ago. ALMA will initially comprise 66 high-precision antennas, with the option to expand in the future. There will be an array of fifty 12-meter diameter antennas, acting together as a single giant telescope, and a compact array composed of 7-meter and 12-meter antennas. The first 12-meter antenna to be handed over to the observatory was built by Mitsubishi Electric Corporation for the National Astronomical Observatory of Japan, one of the ALMA partners. It will shortly be joined by North American and European antennas. “Our Japanese colleagues have produced this state-of-the-art antenna to exacting specifications. We are very excited about the handover because now we can fully equip this antenna for scientific observations,” said Thijs de Graauw, ALMA Director. Antennas arriving at the ALMA site undergo a series of tests to ensure that they meet the strict requirements of the telescope. The antennas have surfaces accurate to less than the thickness of a human hair, and can be pointed precisely enough to pick out a golf ball at a distance of 9 miles. “The handover of the first Japanese antenna is the crowning achievement of the ALMA Project to date,” said Adrian Russell, the North American ALMA Project Director at NRAO. The

  15. ALMA high performance nutating subreflector

    NASA Astrophysics Data System (ADS)

    Gasho, Victor L.; Radford, Simon J. E.; Kingsley, Jeffrey S.

    2003-02-01

    For the international ALMA project"s prototype antennas, we have developed a high performance, reactionless nutating subreflector (chopping secondary mirror). This single axis mechanism can switch the antenna"s optical axis by +/-1.5" within 10 ms or +/-5" within 20 ms and maintains pointing stability within the antenna"s 0.6" error budget. The light weight 75 cm diameter subreflector is made of carbon fiber composite to achieve a low moment of inertia, <0.25 kg m2. Its reflecting surface was formed in a compression mold. Carbon fiber is also used together with Invar in the supporting structure for thermal stability. Both the subreflector and the moving coil motors are mounted on flex pivots and the motor magnets counter rotate to absorb the nutation reaction force. Auxiliary motors provide active damping of external disturbances, such as wind gusts. Non contacting optical sensors measure the positions of the subreflector and the motor rocker. The principle mechanical resonance around 20 Hz is compensated with a digital PID servo loop that provides a closed loop bandwidth near 100 Hz. Shaped transitions are used to avoid overstressing mechanical links.

  16. Sense and sensitivity: How ALMA receivers work

    NASA Astrophysics Data System (ADS)

    Wilson, T. L.; Mauersberger, R.; Hales, A.

    2010-09-01

    In previous articles, we described how electromagnetic waves emitted from objects in the sky are collected by the ALMA antennas (Anatomy of ALMA), and how they are combined in order to produce images. Before these images can be processed, they are picked up by the antennas and concentrated by the large main mirror and a smaller secondary mirror in the so called focal point of each antenna. In order to process the data they must be first converted to electromagnetic waves of a lower frequency and amplified. This is the role of the ALMA receivers. In principle they work like a normal FM receiver, but at much higher frequencies. Here we describe how they work and what makes them special.

  17. The First Six ALMA Band 10 Receivers

    NASA Astrophysics Data System (ADS)

    Fujii, Y.; Gonzalez, A.; Kroug, M.; Kaneko, K.; Miyachi, A.; Yokoshima, T.; Kuroiwa, K.; Ogawa, H.; Makise, K.; Wang, Z.; Uzawa, Y.

    2013-01-01

    The first six Atacama Large Millimeter/submillimeter Array (ALMA) Band 10 (787-950 GHz) receivers have been developed and characterized during the receiver preproduction phase. State-of-the-art measurement systems at THz frequencies have been implemented and successfully used to measure the performance of the first six receivers. Extensive tests ranging from receiver sensitivity and stability to optical aperture efficiency on the secondary antenna have been performed. Performance of all six receivers is well within the stringent ALMA requirements. Moreover, our extensive tests have shown that there are no big performance differences between receivers. These results indicate that the ALMA Band 10 receiver is ready for the production phase, during which an additional 67 receivers will be produced and characterized.

  18. The ALMA Science Archive: Data Flow

    NASA Astrophysics Data System (ADS)

    Manning, A.; Wicenec, A.; Checcucci, A.; Gonzalez Villalba, J. A.

    2012-09-01

    The Atacama Large Millimeter Array (ALMA) relies on a globally distributed Archive across 4 continents to disseminate scientific data to the community and ensure the safety of the data against disaster. The last year has seen the realisation of this design with data flowing from the Atacama desert in Chile out to the ALMA Regional Centers, via Santiago. Here we give a high level overview of the computers and networks that are in place to support this and of the current data volume and capacity as the observatory prepares for it's first observing cycle.

  19. TELCAL: The On-line Calibration Software for ALMA

    NASA Astrophysics Data System (ADS)

    Broguière, D.; Lucas, R.; Pardo, J.; Roche, J.-C.

    2011-07-01

    The ALMA on-line calibration regroups all the operations needed to maintain the ALMA interferometer optimally tuned to successfully execute the planned observations. The results of the calibrations are used in quasi-real time by the ALMA Control System. Since the first ALMA antennas were put into operation in 2009, TELCAL has been used for all the basic calibration operations and is still being improved following the project advancement. We describe here the calibrations done by TELCAL, its relationships with the other ALMA software subsystems and, briefly, the architecture of the software based on CORBA.

  20. First ALMA Transporter Ready for Challenging Duty

    NASA Astrophysics Data System (ADS)

    2008-07-01

    The first of two ALMA transporters -- unique vehicles designed to move high-tech radio-telescope antennas in the harsh, high-altitude environment of the Atacama Large Millimeter/submillimeter Array -- has been completed and passed its initial operational tests. The 130-ton machine moves on 28 wheels and will be able to transport a 115-ton antenna and set it down on a concrete pad within millimeters of a prescribed position. ALMA Transporter The ALMA Transporter on a Test Run CREDIT: ESO Click on image for high-resolution file (244 KB) The ALMA transporter rolled out of its hangar and underwent the tests at the Scheuerle Fahrzeugfabrik company site near Nuremberg, Germany. The machine is scheduled for delivery at the ALMA site in Chile by the end of 2007, and a second vehicle will follow about three months later. ALMA is a giant, international observatory under construction in the Atacama Desert of northern Chile at an elevation of 16,500 feet. Using at least 66 high-precision antennas, with the possibility of increasing the number in the future, ALMA will provide astronomers with an unprecedented ability to explore the Universe as seen at wavelengths of a few millimeters to less than a millimeter. By moving the antennas from configurations as compact as 150 meters to as wide as 15 kilometers, the system will provide a zoom-lens ability for scientists. "The ability to move antennas to reconfigure the array is vital to fulfilling ALMA's scientific mission. The operations plan calls for moving antennas on a daily basis to provide the flexibility that will be such a big part of ALMA's scientific value. That's why the transporters are so important and why this is such a significant milestone," said Adrian Russell, North American Project Manager for ALMA. "The ALMA antennas will be assembled and their functionality will be verified at a base camp, located at an altitude of 2900 meters (9500 feet) and the transporters will in a first step bring the telescopes up to the

  1. ESO and NSF Sign Agreement on ALMA

    NASA Astrophysics Data System (ADS)

    2003-02-01

    Green Light for World's Most Powerful Radio Observatory On February 25, 2003, the European Southern Observatory (ESO) and the US National Science Foundation (NSF) are signing a historic agreement to construct and operate the world's largest and most powerful radio telescope, operating at millimeter and sub-millimeter wavelength. The Director General of ESO, Dr. Catherine Cesarsky, and the Director of the NSF, Dr. Rita Colwell, act for their respective organizations. Known as the Atacama Large Millimeter Array (ALMA), the future facility will encompass sixty-four interconnected 12-meter antennae at a unique, high-altitude site at Chajnantor in the Atacama region of northern Chile. ALMA is a joint project between Europe and North America. In Europe, ESO is leading on behalf of its ten member countries and Spain. In North America, the NSF also acts for the National Research Council of Canada and executes the project through the National Radio Astronomy Observatory (NRAO) operated by Associated Universities, Inc. (AUI). The conclusion of the ESO-NSF Agreement now gives the final green light for the ALMA project. The total cost of approximately 650 million Euro (or US Dollars) is shared equally between the two partners. Dr. Cesarsky is excited: "This agreement signifies the start of a great project of contemporary astronomy and astrophysics. Representing Europe, and in collaboration with many laboratories and institutes on this continent, we together look forward towards wonderful research projects. With ALMA we may learn how the earliest galaxies in the Universe really looked like, to mention but one of the many eagerly awaited opportunities with this marvellous facility". "With this agreement, we usher in a new age of research in astronomy" says Dr. Colwell. "By working together in this truly global partnership, the international astronomy community will be able to ensure the research capabilities needed to meet the long-term demands of our scientific enterprise, and

  2. The ALMA Commissioning and Science Verification Team

    NASA Astrophysics Data System (ADS)

    Hales, A.; Sheth, K.; Wilson, T. L.

    2010-04-01

    The goal of Commissioning is to take ALMA from the stage reached at the end of AIV, that is, a system that functions at an engineering level to an instrument that meets the science / astronomy requirements. Science Verification is the quantitative confirmation that the data produced by the instrument is valid and has the required characteristics in terms of sensitivity, image quality and accuracy.

  3. Alma Flor Ada: Writer, Translator, Storyteller.

    ERIC Educational Resources Information Center

    Brodie, Carolyn S.

    2003-01-01

    Discusses the work of children's author Alma Flor Ada, a Cuban native who has won awards honoring Latino writers and illustrators. Includes part of an interview that explores her background, describes activity ideas, and presents a bibliography of works written by her (several title published in both English and Spanish) as well as sources of…

  4. ALMA communication backbone in Chile goes optical

    NASA Astrophysics Data System (ADS)

    Filippi, G.; Ibsen, J.; Jaque, Sandra; Liello, F.; Navarro, C.

    2014-07-01

    High-bandwidth communication has become a key factor for scientific installations as Observatories. This paper describes the technical, organizational, and operational goals and the level of completion of the ALMA Optical Link Project. The project focus is the creation and operation of an effective and sustainable communication infrastructure to connect the ALMA Observatory, located in the Atacama Desert, in the Northern region of Chile, with the point of presence in ANTOFAGASTA, about 400km away, of the EVALSO infrastructure, and from there to the Central Office in the Chilean capital, Santiago. This new infrastructure that will be operated in behalf of ALMA by REUNA, the Chilean National Research and Education Network, will use state of the art technologies, like dark fiber from newly built cables and DWDM transmission, allowing extending the reach of high capacity communication to the remote region where the Observatory is located. When completed, the end-to-end Gigabit-per-second (Gbps) capable link will provide ALMA with a modern, effective, robust, communication infrastructure capable to cope with present and future demands, like those coming from fast growing data transfer to rapid response mode, from remote monitoring and engineering to virtual presence.

  5. Report on the ''ALMA Developers' Workshop''

    NASA Astrophysics Data System (ADS)

    Laing, R.; Mroczkowski, T.; Testi, L.

    2016-09-01

    A workshop was recently held in Gothenburg to discuss the ALMA Development Programme for the period 2015-2030. The main aims were to inform the European and international communities about progress on current development projects, to solicit new ideas and to discuss priorities for the future. This contribution summarises the outcomes of the workshop.

  6. The ALMA Real Time Control System

    NASA Astrophysics Data System (ADS)

    Kern, Jeffrey S.; Juerges, Thomas A.; Marson, Ralph G.

    2009-01-01

    The Atacama Large Millimeter Array (ALMA) is a revolutionary millimeter and submillimeter array being developed on the Atacama plateau of northern Chile. An international partnership lead by NRAO, ESO, and NAOJ this powerful and flexible telescope will provide unprecedented observations of this relatively unexplored frequency range. The control subsystem for the Atacama Large Millimeter Array must coordinate the monitor and control of at least sixty six antennas (in four different styles), two correlators, and all of the ancillary equipment (samplers, local oscillators, front ends, etc.). This equipment will be spread over tens of kilometers and operated remotely. Operation of the array requires a robust, scalable, and maintainable real time control system. The real time control system is responsible for monitoring and control of any devices where there are fixed deadlines. Examples in the ALMA context are antenna pointing and fringe tracking. Traditionally the real time portion of a large software system is an intricate and error prone portion of the software. As a result the real time portion is very expensive in terms of effort expended both during construction and during maintenance phases of a project. The ALMA real time control system uses a Linux based real time operating system to interact with the hardware and the CORBA based ALMA Common Software to communicate in the distributed computing environment. Mixing the requirements of real time computing and the non-deterministic CORBA middleware has produced an interesting design. We discuss the architecture, design, and implementation of the ALMA real time control system. Highlight some lessons learned along the way, and justify our assertion that this should be the last large scale real time control system in radio astronomy.

  7. First Test Images made with ALMA

    NASA Astrophysics Data System (ADS)

    2011-01-01

    In this issue we are presenting the first test images taken with up to eight of the ALMA antennas. These images were just the by-product of a series of vigorous tests of the hardware and software components of the whole system made during the second half of 2010. No special effort has been made to obtain the best possible UV coverage or calibration. Some of the images were made with all eight antennas available at that time, others just with a subset. Therefore the images should not be used to draw scientific conclusions on the observed objects or to question existing observations. The purpose of this series of pictures is to, hopefully, convince readers of this newsletter that ALMA is going to be reality very soon.

  8. Star Formation Research - Now And With Alma

    NASA Astrophysics Data System (ADS)

    Shepherd, Debra S.

    2006-06-01

    Optical, infrared, X-ray, and radio (single dish and interferometric) observations of star forming regions have made great strides toward improving our understanding of the characteristics and evolution of molecular clouds and embedded forming stars and their circumstellar disks. Once the Atacama Large Millimeter Array (ALMA) is completed, it will provide a significant increase in sensitivity and resolution at millimeter and sub-millimeter wavelengths that will allow all astronomers to address critical issues that cannot be explored with established observatories. I will review our current observational limitations and provide examples about how ALMA will contribute to the study of star forming regions and compliment other new or expanded observatories at optical, infrared, and radio wavelengths.The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

  9. Detecting the First Quasars with ALMA

    NASA Astrophysics Data System (ADS)

    Schleicher, Dominik R. G.; Spaans, Marco; Klessen, Ralf S.

    2010-05-01

    We show that ALMA is the first telescope that can probe the dust-obscured central region of quasars at z > 5 with a maximum resolution of ~ 30 pc employing the 18 km baseline. We explore the possibility of detecting the first quasars with ALMA (Schleicher, Spaans, & Klessen 2009). For this purpose, we adopt the Seyfert 2 galaxy NGC 1068 as a reference system and calculate the expected fluxes if this galaxy were placed at high redshift. This choice is motivated by the detailed observations available for this system and the absence of any indication for an evolution in metallicity in high-redshift quasars. It is a conservative choice due to the moderate column densities in NGC 1068, leading to moderate fluxes.

  10. Time synchronization within the ALMA software infrastructure

    NASA Astrophysics Data System (ADS)

    Amestica, Rodrigo; Gustafsson, Birger; Marson, Ralph

    2006-06-01

    The Atacama Large Millimeter Array (ALMA) is an international telescope project currently under construction in the Atacama desert of Chile. It has a provision for 64 antennas of 12m each, arranged over a geographical area of a few square kilometers. Antenna control and correlated data acquisition is implemented by means of a distributed set of realtime Linux computers, each one hosting ALMA Common Software (ACS) based applications and connected to a common time base distributed by the ALMA Master Clock as a 48ms electronic pulse signal (time event). All these computers require to be time synchronized for achieving coordination between commands and data acquisition. For this purpose, the ArrayTime system presented here implements a real-time software facility that makes possible to unambiguously time-stamp each time event arriving at each computer node (distributed clock), relative to an external time source of 1Hz and in phase to the TAI second. Array time is the absolute time of each time event, and synchronization of distributed clocks is resolved by communicating the array time, via ACS services, for the next time event interrupt at least once during the operational cycle of the distributed clock. Thereafter, it is possible to schedule application tasks within a latency range of 100us by extrapolating from the last interrupt and based on the current CPU Time Stamp Counter (TSC) and the estimated frequency of the CPU clock. In the following, we present a description of the elements that constitute the ArrayTime facility.

  11. Application development using the ALMA common software

    NASA Astrophysics Data System (ADS)

    Chiozzi, G.; Caproni, A.; Jeram, B.; Sommer, H.; Wang, V.; Plesko, M.; Sekoranja, M.; Zagar, K.; Fugate, D. W.; Harrington, S.; Di Marcantonio, P.; Cirami, R.

    2006-06-01

    The ALMA Common Software (ACS) provides the software infrastructure used by ALMA and by several other telescope projects, thanks also to the choice of adopting the LGPL public license. ACS is a set of application frameworks providing the basic services needed for object oriented distributed computing. Among these are transparent remote object invocation, object deployment and location based on a container/component model, distributed error, alarm handling, logging and events. ACS is based on CORBA and built on top of free CORBA implementations. Free software is extensively used wherever possible. The general architecture of ACS was presented at SPIE 2002. ACS has been under development for 6 years and it is midway through its development life. Many applications have been written using ACS; the ALMA test facility, APEX and other telescopes are running systems based on ACS. This is therefore a good time to look back and see what have been until now the strong and the weak points of ACS in terms of architecture and implementation. In this perspective, it is very important to analyze the applications based on ACS, the feedback received by the users and the impact that this feedback has had on the development of ACS itself, by favoring the development of some features with respect to others. The purpose of this paper is to describe the results of this analysis and discuss what we would like to do in order to extend and improve ACS in the coming years, in particular to make application development easier and more efficient.

  12. Probing Massive Star Cluster Formation with ALMA

    NASA Astrophysics Data System (ADS)

    Johnson, Kelsey

    2015-08-01

    Observationally constraining the physical conditions that give rise to massive star clusters has been a long-standing challenge. Now with the ALMA Observatory coming on-line, we can finally begin to probe the birth environments of massive clusters in a variety of galaxies with sufficient angular resolution. In this talk I will give an overview of ALMA observations of galaxies in which candidate proto-super star cluster molecular clouds have been identified. These new data probe the physical conditions that give rise to super star clusters, providing information on their densities, pressures, and temperatures. In particular, the observations indicate that these clouds may be subject to external pressures of P/k > 108 K cm-3, which is consistent with the prevalence of optically observed adolescent super star clusters in interacting galaxy systems and other high pressure environments. ALMA observations also enable an assessement of the molecular cloud chemical abundances in the regions surrounding super star clusters. Molecular clouds associated with existing super star clusters are strongly correlated with HCO+ emission, but appear to have relatively low ratio of CO/HCO+ emission compared to other clouds, indicating that the super star clusters are impacting the molecular abundances in their vicinity.

  13. The Atacama Large Millimeter Array (ALMA)

    NASA Astrophysics Data System (ADS)

    1999-06-01

    The Atacama Large Millimeter Array (ALMA) is the new name [2] for a giant millimeter-wavelength telescope project. As described in the accompanying joint press release by ESO and the U.S. National Science Foundation , the present design and development phase is now a Europe-U.S. collaboration, and may soon include Japan. ALMA may become the largest ground-based astronomy project of the next decade after VLT/VLTI, and one of the major new facilities for world astronomy. ALMA will make it possible to study the origins of galaxies, stars and planets. As presently envisaged, ALMA will be comprised of up to 64 12-meter diameter antennas distributed over an area 10 km across. ESO PR Photo 24a/99 shows an artist's concept of a portion of the array in a compact configuration. ESO PR Video Clip 03/99 illustrates how all the antennas will move in unison to point to a single astronomical object and follow it as it traverses the sky. In this way the combined telescope will produce astronomical images of great sharpness and sensitivity [3]. An exceptional site For such observations to be possible the atmosphere above the telescope must be transparent at millimeter and submillimeter wavelengths. This requires a site that is high and dry, and a high plateau in the Atacama desert of Chile, probably the world's driest, is ideal - the next best thing to outer space for these observations. ESO PR Photo 24b/99 shows the location of the chosen site at Chajnantor, at 5000 meters altitude and 60 kilometers east of the village of San Pedro de Atacama, as seen from the Space Shuttle during a servicing mission of the Hubble Space Telescope. ESO PR Photo 24c/99 and ESO PR Photo 24d/99 show a satellite image of the immediate vicinity and the site marked on a map of northern Chile. ALMA will be the highest continuously operated observatory in the world. The stark nature of this extreme site is well illustrated by the panoramic view in ESO PR Photo 24e/99. High sensitivity and sharp images ALMA

  14. The ALMA Observing Tool: A Brief Introduction and Status Report

    NASA Astrophysics Data System (ADS)

    Bridger, A.

    2009-09-01

    A short introduction to the motivation and design of the ALMA Observing Tool for proposal and observation preparation is given. This is supplemented by a rapid tour of the tool's features, a summary of its current status, and the plans for its completion for use by ALMA observers and staff.

  15. NRAO Welcomes Taiwan as a New North American ALMA Partner

    NASA Astrophysics Data System (ADS)

    2008-12-01

    The National Radio Astronomy Observatory (NRAO) has announced a formal agreement enabling Taiwanese astronomers to participate in the North American component of the international ALMA partnership, alongside American and Canadian astronomers. Taiwan's efforts will be led by the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA). ALMA, the Atacama Large Millimeter/submillimeter Array, is the most ambitious ground-based astronomical observatory in history. Currently under construction in Chile’s Atacama Desert at an altitude of 16,500 feet, it promises to revolutionize our understanding of the formation of planets, stars, and galaxies when it begins full science operations early in the next decade. The agreement, signed by the Taipei Economic and Cultural Representative Office and the American Institute in Taiwan, provides for approximately $20 million in ALMA construction funding through the National Science Council (NSC), Taiwan’s equivalent to the US National Science Foundation (NSF) and Canada's National Research Council (NRC), which have jointly funded North America's existing contribution to the international ALMA project. Activities under the agreement will include joint research projects, development projects, collaboration on construction, support of observatory operations and other forms of cooperation. Access to ALMA observing time will be shared, as will membership on advisory committees. “Taiwan is a world-class center for submillimeter-wavelength astronomical research, and we’re delighted that the ALMA project and all its future users will benefit from the resources and expertise that Taiwan’s deepening participation brings to this great, global endeavor,” said Dr. Fred Lo, NRAO's director. This new agreement increases and diversifies Taiwan’s Academia Sinica investment in ALMA beyond the levels achieved through its participation in the East Asian component of the ALMA partnership, which is led by the National Astronomical

  16. The ALMA Phasing Project: New Frontiers in Ultra-High Resolution Astronomy Enabled by a Beamformed ALMA

    NASA Astrophysics Data System (ADS)

    Matthews, Lynn D.; Alef, W.; Anderson, J.; Barkats, D.; Crew, G. B.; Doeleman, S. S.; Fish, V. L.; Greenberg, J.; Hecht, M. H.; Hiriart, R.; Honma, M.; Impellizzeri, C.; Inoue, M.; Lacasse, R.; Lopez, B.; Mora-Klein, M.; Nagar, N.; Pankratius, V.; Pradel, N.; Rottmann, H.; Roy, A.; Ruszczyk, C.; Saez, A.; Shillue, B.; Treacy, R.; ALMA Phasing Project Team

    2014-01-01

    The Atacama Millimeter/submillimeter Array (ALMA) Phasing Project (APP) is an ongoing ALMA Development Project that will provide the means to coherently sum all of the individual ALMA antennas, allowing them to effectively function as a single aperture. This capability will allow ALMA to participate in global Very Long Baseline Interferometry (VLBI) networks operating in the millimeter and submillimeter, offering a dramatic improvement in sensitivity. This will in turn afford a wide range of new ultra-high angular resolution science applications. This poster will provide an overview of the APP design and implementation plan and highlight examples of new science enabled by a beamformed ALMA (including the study of black holes on Event Horizon scales, the detailed investigation of the launch and collimation of astrophysical jets, and astrometry of astrophysical masers with unprecedented precision). Commissioning and Science Verification of the APP is slated to begin in early 2014.

  17. ALMA Achieves Major Milestone With Antenna-Link Success

    NASA Astrophysics Data System (ADS)

    2007-03-01

    The Atacama Large Millimeter/submillimeter Array (ALMA), an international telescope project, reached a major milestone on March 2, when two ALMA prototype antennas were first linked together as an integrated system to observe an astronomical object. The milestone achievement, technically termed "First Fringes," came at the ALMA Test Facility (ATF) on the grounds of the National Radio Astronomy Observatory's (NRAO) Very Large Array (VLA) radio telescope in New Mexico. NRAO is a facility of the National Science Foundation (NSF), managed by Associated Universities, Incorporated (AUI). AUI also is designated by NSF as the North American Executive for ALMA. ALMA Test Facility ALMA Test Facility, New Mexico: VertexRSI antenna, left; AEC antenna, right. CREDIT: Drew Medlin, NRAO/AUI/NSF Click on image for page of graphics and full information Faint radio waves emitted by the planet Saturn were collected by the two ALMA antennas, then processed by new, state-of-the-art electronics to turn the two antennas into a single, high-resolution telescope system, called an interferometer. Such pairs of antennas are the basic building blocks of multi-antenna imaging systems such as ALMA and the VLA. In such a system, each antenna is combined electronically with every other antenna to form a multitude of pairs. Each pair contributes unique information that is used to build a highly-detailed image of the astronomical object under observation. When completed in 2012, ALMA will have 66 antennas. The successful Saturn observation began at 7:13 p.m., U.S. Mountain Time Friday (0213 UTC Saturday). The planet's radio emissions at a frequency of 104 GigaHertz (GHz) were tracked by the ALMA system for more than an hour. "Our congratulations go to the dedicated team of scientists, engineers and technicians who produced this groundbreaking achievement for ALMA. Much hard work and many long hours went into this effort, and we appreciate it all. This team should be very proud today," said NRAO

  18. The Atacama Large Millimeter Array (ALMA)

    NASA Astrophysics Data System (ADS)

    1999-06-01

    The Atacama Large Millimeter Array (ALMA) is the new name [2] for a giant millimeter-wavelength telescope project. As described in the accompanying joint press release by ESO and the U.S. National Science Foundation , the present design and development phase is now a Europe-U.S. collaboration, and may soon include Japan. ALMA may become the largest ground-based astronomy project of the next decade after VLT/VLTI, and one of the major new facilities for world astronomy. ALMA will make it possible to study the origins of galaxies, stars and planets. As presently envisaged, ALMA will be comprised of up to 64 12-meter diameter antennas distributed over an area 10 km across. ESO PR Photo 24a/99 shows an artist's concept of a portion of the array in a compact configuration. ESO PR Video Clip 03/99 illustrates how all the antennas will move in unison to point to a single astronomical object and follow it as it traverses the sky. In this way the combined telescope will produce astronomical images of great sharpness and sensitivity [3]. An exceptional site For such observations to be possible the atmosphere above the telescope must be transparent at millimeter and submillimeter wavelengths. This requires a site that is high and dry, and a high plateau in the Atacama desert of Chile, probably the world's driest, is ideal - the next best thing to outer space for these observations. ESO PR Photo 24b/99 shows the location of the chosen site at Chajnantor, at 5000 meters altitude and 60 kilometers east of the village of San Pedro de Atacama, as seen from the Space Shuttle during a servicing mission of the Hubble Space Telescope. ESO PR Photo 24c/99 and ESO PR Photo 24d/99 show a satellite image of the immediate vicinity and the site marked on a map of northern Chile. ALMA will be the highest continuously operated observatory in the world. The stark nature of this extreme site is well illustrated by the panoramic view in ESO PR Photo 24e/99. High sensitivity and sharp images ALMA

  19. World-Wide Effort Bringing ALMA Telescope Into Reality

    NASA Astrophysics Data System (ADS)

    2008-02-01

    In the thin, dry air of northern Chile's Atacama Desert, at an altitude of 16,500 feet, an amazing new telescope system is taking shape, on schedule to provide the world's astronomers with unprecedented views of the origins of stars, galaxies, and planets. The Atacama Large Millimeter/submillimeter Array (ALMA) will open an entirely new "window" on the Universe, allowing scientists to unravel longstanding and important astronomical mysteries. ALMA Artist's Concept Artist's Concept of Completed ALMA CREDIT: ALMA/ESO/NRAO/NAOJ Click on image for high-resolution file (182 KB) "Most of the photons in the Universe are in the wavelength range that ALMA will receive, and ALMA will give us our first high-resolution views at these wavelengths. This will be a tremendous advancement for astronomy and open one of our science's last frontiers," Anneila Sargent, a Caltech professor and ALMA Board member, told the American Association for the Advancement of Science at its meeting in Boston, Mass. The millimeter and submillimeter wavelength range lies between what is traditionally considered radio waves and infrared waves. ALMA, a system using up to 66 high-precision dish antennas working together, will provide astronomers with dramatically greater sensitivity, the ability to detect faint objects, and resolving power, the ability to see fine detail, than has ever before been available in this range. "This ambitious project is the product of an international collaboration that spans the globe," Sargent said. "ALMA truly will enable transformational science and providing this capability has required a massive, world-wide effort," she added. The ALMA project is a partnership between Europe, Japan and North America in cooperation with the Republic of Chile. ALMA is funded in Europe by ESO, in Japan by the National Institutes of Natural Sciences in cooperation with the Academia Sinica in Taiwan and in North America by the U.S. National Science Foundation in cooperation with the

  20. Quasi-optical attenuators for ALMA band 10 receiver

    NASA Astrophysics Data System (ADS)

    Gonzalez, A.; Fujii, Y.; Kaneko, K.; Uzawa, Y.

    2011-12-01

    Simple quasi-optical attenuators based on beam truncation have been designed, fabricated and tried on ALMA band 10 receivers (787-950 GHz) with optimal results. The design is based on physical-optics simulations considering effects of diffraction. The use of these attenuators allows flexibility in the design of the local oscillator (LO) quasi-optical injection scheme depending on the specific performance of components for each of the 73 ALMA band 10 receivers. In particular, they have proven very effective to keep system noise within the stringent ALMA requirements (230 K at 80% of 787-950 GHz band).

  1. ALMA Partners Break Ground on World's Largest Millimeter Wavelength Telescope

    NASA Astrophysics Data System (ADS)

    2003-11-01

    Scientists and dignitaries from North America, Europe, and Chile broke ground today (Thursday, November 6, 2003) on what will be the world's largest, most sensitive radio telescope operating at millimeter wavelengths. ALMA - the Atacama Large Millimeter Array - will be a single instrument composed of 64 high-precision antennas located on the Chajnantor plain of the Chilean Andes in the District of San Pedro de Atacama, 16,500 feet (5,000 meters) above sea level. ALMA's primary function will be to observe and image with unprecedented clarity the enigmatic cold regions of the Universe, which are optically dark, yet shine brightly in the millimeter portion of the electromagnetic spectrum. ALMA Array Artist's Conception of ALMA Array in Compact Configuration (Click on Image for Larger Version) Other Images Available: Artist's conception of the antennas for the Atacama Large Millimeter Array Moonrise over ALMA test equipment near Cerro Chajnantor, Chile VertexRSI antenna at the VLA test site The Atacama Large Millimeter Array is an international astronomy facility. ALMA is an equal partnership between Europe and North America, in cooperation with the Republic of Chile, and is funded in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC), and in Europe by the European Southern Observatory (ESO) and Spain. ALMA construction and operations are led on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI), and on behalf of Europe by ESO. "The U.S. National Science Foundation joins today with our North American partner, Canada, and with the European Southern Observatory, Spain, and Chile to prepare for a spectacular new instrument," said Dr. Rita Colwell, director of the U.S. National Science Foundation. "The Atacama Large Millimeter Array will expand our vision of the Universe with "eyes" that pierce the shrouded mantles of

  2. ALMA Correlator Real-Time Data Processor

    NASA Astrophysics Data System (ADS)

    Pisano, J.; Amestica, R.; Perez, J.

    2005-10-01

    The design of a real-time Linux application utilizing Real-Time Application Interface (RTAI) to process real-time data from the radio astronomy correlator for the Atacama Large Millimeter Array (ALMA) is described. The correlator is a custom-built digital signal processor which computes the cross-correlation function of two digitized signal streams. ALMA will have 64 antennas with 2080 signal streams each with a sample rate of 4 giga-samples per second. The correlator's aggregate data output will be 1 gigabyte per second. The software is defined by hard deadlines with high input and processing data rates, while requiring interfaces to non real-time external computers. The designed computer system - the Correlator Data Processor or CDP, consists of a cluster of 17 SMP computers, 16 of which are compute nodes plus a master controller node all running real-time Linux kernels. Each compute node uses an RTAI kernel module to interface to a 32-bit parallel interface which accepts raw data at 64 megabytes per second in 1 megabyte chunks every 16 milliseconds. These data are transferred to tasks running on multiple CPUs in hard real-time using RTAI's LXRT facility to perform quantization corrections, data windowing, FFTs, and phase corrections for a processing rate of approximately 1 GFLOPS. Highly accurate timing signals are distributed to all seventeen computer nodes in order to synchronize them to other time-dependent devices in the observatory array. RTAI kernel tasks interface to the timing signals providing sub-millisecond timing resolution. The CDP interfaces, via the master node, to other computer systems on an external intra-net for command and control, data storage, and further data (image) processing. The master node accesses these external systems utilizing ALMA Common Software (ACS), a CORBA-based client-server software infrastructure providing logging, monitoring, data delivery, and intra-computer function invocation. The software is being developed in tandem

  3. Astrochemical Modeling In the ALMA Era

    NASA Technical Reports Server (NTRS)

    Charnley, Steven

    2009-01-01

    Interstellar chemistry provides a natural laboratory for studying exotic species and processes at densities, temperatures, and reaction rates, that are difficult or impractical to address in the laboratory. Thus, many chemical reactions considered too slow by the standards of terrestrial chemistry, can be observed' and modeled. Various proposals concerning the nature and chemistry of complex interstellar organic molecules will be described. Catalytic reactions on grain surfaces can, in principle, lead to a large variety of species and this has motivated many laboratory and theoretical studies. Gas phase processes may also build large species in molecular clouds. Future laboratory data and computational tools needed to construct accurate chemical models of various sources to be observed by ALMA will be outlined.

  4. ALMA observations of the Orion proplyds

    SciTech Connect

    Mann, Rita K.; Di Francesco, James; Johnstone, Doug; Matthews, Brenda C.; Andrews, Sean M.; Williams, Jonathan P.; Bally, John; Ricci, Luca; Hughes, A. Meredith

    2014-03-20

    We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of protoplanetary disks ('proplyds') in the Orion Nebula Cluster. We imaged five individual fields at 856 μm containing 22 Hubble Space Telescope (HST)-identified proplyds and detected 21 of them. Eight of those disks were detected for the first time at submillimeter wavelengths, including the most prominent, well-known proplyd in the entire Orion Nebula, 114-426. Thermal dust emission in excess of any free-free component was measured in all but one of the detected disks, and ranged between 1 and 163 mJy, with resulting disk masses of 0.3-79 M {sub jup}. An additional 26 stars with no prior evidence of associated disks in HST observations were also imaged within the 5 fields, but only 2 were detected. The disk mass upper limits for the undetected targets, which include OB stars, θ{sup 1} Ori C, and θ{sup 1} Ori F, range from 0.1 to 0.6 M {sub jup}. Combining these ALMA data with previous Submillimeter Array observations, we find a lack of massive (≳3 M {sub jup}) disks in the extreme-UV-dominated region of Orion, within 0.03 pc of θ{sup 1} Ori C. At larger separations from θ{sup 1} Ori C, in the far-UV-dominated region, there is a wide range of disk masses, similar to what is found in low-mass star forming regions. Taken together, these results suggest that a rapid dissipation of disk masses likely inhibits potential planet formation in the extreme-UV-dominated regions of OB associations, but leaves disks in the far-UV-dominated regions relatively unaffected.

  5. ALMA Presents a Transformational View of the Universe

    NASA Astrophysics Data System (ADS)

    Wootten, Al

    2015-01-01

    ALMA Early Science results began transforming astronomy in 2011. Construction has recently ended as scheduled and on budget.* Seven receiver bands achieve wavelength coverage sweeping from 3mm to 0.3mm across a decade of nearly complete frequency access, broken only by the atmospheric limitations of its spectacular site. With access to nearly any line redshifted within that range, ALMA's sensitivity allows it to address the questions of how the first stars and galaxies in the Universe were born, to measure the abundances of the first metals and to chronicle the development of isotopic diversity among the elements.* As this is written, the longest baselines are being commissioned for ALMA, enabling resolutions down to 0.01". Very long baseline capability, also currently under initial testing, can tie other antennas' collecting area in with ALMA's to create a global telescope capable of delineating detail as fine as ten microarcseconds, allowing imaging of the black hole at the center of our galaxy.Already ALMA has changed paradigms for objects both distant and near. Oxygen and carbon, the most abundant metals produced by the first stars, and CO all have lines detectable by ALMA in its wavelength range. The 157 micron [C II] line has already been detected out to z~7 in ALMA Early Science observations. ALMA's sensitivity and resolution have revolutionized the study of circumstellar planet-forming disks. Molecular imaging has revealed CO 'snow lines' in those disks, delineating where in a disk mid plane where ice grains may form as the temperature drops. ALMA has also imaged highly asymmetric distribution of gas and particularly of dust in evolved disks, revealing 'dust traps' where new planets may form from agglomerated material.ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI

  6. ALMA does Galaxies! A User's Perspective on Early Science

    NASA Astrophysics Data System (ADS)

    Turner, Jean

    2011-01-01

    Star formation and its regulation, rotation curves, dust and gas masses, gas dynamics and secular evolution of galaxies, interactions and mergers, cosmic pyrotechnics, and monster-feeding are among the many topics that can be studied with ALMA. We talk about many of the explorations of the extragalactic world that are possible with this awesome instrument in its Early Science incarnation, and discuss how these first generation studies with Early-ALMA compare to what will eventually be possible with the full array.

  7. ALMA Telescope Passes Major Milestone with Successful Antenna Link

    NASA Astrophysics Data System (ADS)

    2009-05-01

    The Atacama Large Millimeter/submillimeter Array (ALMA), an immense international telescope project under construction in northern Chile, reached a major milestone on April 30, when two ALMA antennas were linked together as an integrated system to observe an astronomical object for the first time. The milestone achievement, technically termed "First Fringes," came at ALMA’s Operations Support Facility, 9,500 feet above sea level. Faint radio waves emitted by the planet Mars were collected by the two 12-meter diameter ALMA antennas, then processed by state-of-the-art electronics to turn the two antennas into a single, high-resolution telescope system, called an interferometer. Such pairs of antennas are the basic building blocks of imaging systems that enable radio telescopes to deliver pictures that approach or even exceed the resolving power of visible light telescopes. In such a system, each antenna is combined electronically with every other antenna to form a multitude of antenna pairs. Each pair contributes unique information that is used to build a highly-detailed image of the astronomical object under observation. When completed early in the next decade, ALMA’s 66 antennas will provide over a thousand such antenna pairings, with distances between antennas exceeding ten miles. This will enable ALMA to see with a sharpness surpassing that of the best space telescopes. The antennas will operate at an altitude of 16,500 feet, high above the OSF, in one of the best locations on Earth for millimeter-wavelength astronomy, the Chajnantor Plateau in Chile’s Atacama Desert. Last week’s successful Mars observation was conducted at an observing frequency of 104.2 GHz. Astronomers measured the distinctive varying “fringes” detected by the interferometer as the planet moved across the sky. “This is a great success,” said Adrian Russell, North American ALMA Project Director at the National Radio Astronomy Observatory (NRAO), “not because we observed a

  8. U.S., European ALMA Partners Award Prototype Antenna Contracts

    NASA Astrophysics Data System (ADS)

    2000-03-01

    The U.S. and European partners in the Atacama Large Millimeter Array (ALMA) project have awarded contracts to U.S. and Italian firms, respectively, for two prototype antennas. ALMA is a planned telescope array, expected to consist of 64 millimeter-wave antennas with 12-meter diameter dishes. The array will be built at a high-altitude, extremely dry mountain site in Chile's Atacama desert, and is scheduled to be completed sometime in this decade. On February 22, 2000, Associated Universities Inc. (AUI) signed an approximately $6.2 million contract with Vertex Antenna Systems, of Santa Clara, Calif., for construction of one prototype ALMA antenna. AUI operates the U.S. National Radio Astronomy Observatory (NRAO) for the National Science Foundation under a cooperative agreement. The European partners contracted with the consortium of European Industrial Engineering and Costamasnaga, of Mestre, Italy, on February 21, 2000, for the production of another prototype. (Mestre is located on the inland side of Venice.) The two antennas must meet identical specifications, but will inherently be of different designs. This will ensure that the best possible technologies are incorporated into the final production antennas. Only one of the designs will be selected for final production. Several technical challenges must be met for the antennas to perform to ALMA specifications. Each antenna must have extremely high surface accuracy (25 micrometers, or one-third the diameter of a human hair, over the entire 12-meter diameter). This means that, when completed, the surface accuracy of the ALMA dishes will be 20 times greater than that of the Very Large Array (VLA) antennas, and about 50 times greater than dish antennas for communications or radar. The ALMA antennas must also have extremely high pointing accuracy (0.6 arcseconds). An additional challenge is that the antennas, when installed at the ALMA site in Chile, will be exposed to the ravages of weather at 16,500 feet (5000 meters

  9. Exploring remote operation for ALMA Observatory

    NASA Astrophysics Data System (ADS)

    Shen, Tzu-Chiang; Soto, Ruben; Ovando, Nicolás.; Velez, Gaston; Fuica, Soledad; Schemrl, Anton; Robles, Andres; Ibsen, Jorge; Filippi, Giorgio; Pietriga, Emmanuel

    2014-08-01

    The Atacama Large Millimeter /submillimeter Array (ALMA) will be a unique research instrument composed of at least 66 reconfigurable high-precision antennas, located at the Chajnantor plain in the Chilean Andes at an elevation of 5000 m. The observatory has another office located in Santiago of Chile, 1600 km from the Chajnantor plain. In the Atacama desert, the wonderful observing conditions imply precarious living conditions and extremely high operation costs: i.e: flight tickets, hospitality, infrastructure, water, electricity, etc. It is clear that a purely remote operational model is impossible, but we believe that a mixture of remote and local operation scheme would be beneficial to the observatory, not only in reducing the cost but also in increasing the observatory overall efficiency. This paper describes the challenges and experience gained in such experimental proof of the concept. The experiment was performed over the existing 100 Mbps bandwidth, which connects both sites through a third party telecommunication infrastructure. During the experiment, all of the existent capacities of the observing software were validated successfully, although room for improvement was clearly detected. Network virtualization, MPLS configuration, L2TPv3 tunneling, NFS adjustment, operational workstations design are part of the experiment.

  10. Automating engineering verification in ALMA subsystems

    NASA Astrophysics Data System (ADS)

    Ortiz, José; Castillo, Jorge

    2014-08-01

    The Atacama Large Millimeter/submillimeter Array is an interferometer comprising 66 individual high precision antennas located over 5000 meters altitude in the north of Chile. Several complex electronic subsystems need to be meticulously tested at different stages of an antenna commissioning, both independently and when integrated together. First subsystem integration takes place at the Operations Support Facilities (OSF), at an altitude of 3000 meters. Second integration occurs at the high altitude Array Operations Site (AOS), where also combined performance with Central Local Oscillator (CLO) and Correlator is assessed. In addition, there are several other events requiring complete or partial verification of instrument specifications compliance, such as parts replacements, calibration, relocation within AOS, preventive maintenance and troubleshooting due to poor performance in scientific observations. Restricted engineering time allocation and the constant pressure of minimizing downtime in a 24/7 astronomical observatory, impose the need to complete (and report) the aforementioned verifications in the least possible time. Array-wide disturbances, such as global power interruptions and following recovery, generate the added challenge of executing this checkout on multiple antenna elements at once. This paper presents the outcome of the automation of engineering verification setup, execution, notification and reporting in ALMA and how these efforts have resulted in a dramatic reduction of both time and operator training required. Signal Path Connectivity (SPC) checkout is introduced as a notable case of such automation.

  11. ALMA: Millimeter/submillimeter Astronomy at high sensitivity and resolution

    NASA Astrophysics Data System (ADS)

    Wootten, Alwyn; Corder, Stuartt Alan; Iono, Daisuke; Testi, Leonardo

    2015-08-01

    Vigorous and transformative investigation of the millimeter/submillimeter sky at high sensitivity and high resolution has benefitted from the recent completion of the Atacama Large Millimeter/submillimeter Array (ALMA), an effort of 22 countries. ALMA, a versatile interferometric telescope at 5000m elevation in the Atacama Desert of northern Chile, is comprised of sixty-six precision telescopes which may be arrayed over a 16 km extent on the high Chajnantor plain. Owing to its large collecting area of over 6600m^2 and its commodious spectral grasp of 8 GHz of spectrum in dual polarizations within an 84-950 GHz range, ALMA provides astronomers with vastly improved spectroscopic sensitivity. Spatial resolutions of 30 milliarcsec were demonstrated recently, revealing rings within the HL Tau protoplanetary disk, the rotating structure of the asteroid Juno and the molecular structure of the z~3 lensed galaxy SDP.81. The astrometric accuracy even at this early stage of deployment is better than 3 milliarcsec, providing improved ephemerides for the encounter of the New Horizons spacecraft with the Pluto-Charon system. Very long baseline capability is expected to bring microarcsecond imaging to a worldwide array anchored by ALMA with potential for imaging nearby Black Holes on the scales of their Event Horizons.ALMA's huge collecting area has enabled detection of lines of C, N and CO and continuum for characterization of massive complexes near the Era of Recombination. ALMA's sensitivity and resolution have enabledmeasurement of molecular emission through cosmic time from numerous molecules characterizing galactic star-forming regions and tracing their kinematics near active nuclei, starbursts, interacting clouds and quiescent disks. ALMA's sensitivity, resolution and spectral grasp have enabled it to image molecules and dust characterizing circumstellar disks and embedded bodies in protostellar, transition and debris stages of development.ALMA is a partnership of ESO

  12. The Soul of Lupus with ALMA (SOLA) Project Overview

    NASA Astrophysics Data System (ADS)

    Saito, M.; de Gregorio, I.; Team SOLA

    2015-12-01

    The SOLA (Soul of Lupus with ALMA) project is conducting comprehensive studies of the Lupus Molecular Clouds and their star formation processes. Our goal is to exploit ALMA and other facilities over a wide wavelength range to establish a prototypical low-mass star forming scenario based on the Lupus region. We focus mainly on 10-104 au scale physics, kinematics, density, and temperature, together with detailed modelling of radiative transfer. Our unique source catalog so far contains more than 700 sources at various evolutionary stages and we have obtained complementary data with Mopra, APEX, etc. In the poster, we will report the latest status of SOLA and the expected outcome in observing runs in the near future, including ALMA Cycle 3.

  13. New Eyes on the Sun — Solar Science with ALMA

    NASA Astrophysics Data System (ADS)

    Wedemeyer, S.

    2016-03-01

    In Cycle 4, which starts in October 2016, the Atacama Large Millimeter/submillimeter Array (ALMA) will be open for regular observations of the Sun for the first time. ALMA’s impressive capabilities have the potential to revolutionise our understanding of our host star, with far-reaching implications for our knowledge about stars in general. The radiation emitted at ALMA wavelengths originates mostly from the chromosphere — a complex and dynamic layer between the photosphere and the corona that is prominent during solar eclipses. Despite decades of intensive research, the chromosphere is still elusive due to its complex nature and the resulting challenges to its observation. ALMA will change the scene substantially by opening up a new window on the Sun, promising answers to long-standing questions.

  14. ALMA's First Insights into the Submillimeter/millimeter Extragalactic Universe

    NASA Astrophysics Data System (ADS)

    Lonsdale, Carol J.

    2012-01-01

    As Early Science observations begin, ALMA is poised to investigate the dusty and molecular extragalactic Universe, from our nearest neighbors to the first galaxies. I will present prospects and early results for extragalactic studies from ALMA's first observing campaigns. Even its current Early Science mode, ALMA will achieve unprecedented sensitivity, frequency range and angular resolution. This will allow it to image the detailed kinematics of molecular flows in nearby AGN cores, resolve individual star-forming structures in other galaxies, and constrain the dynamics of the interstellar medium in cataclysmic mergers of the sort that trigger starbursts and quasars shortly after the epoch of re-ionization. I will demonstrate these fantastic capabilities by showing highlights from the first Early Science and Science Verification observations, including imaging of the nearby major mergers NGC 3256 and the Antennae.

  15. η Carinae Baby Homunculus Uncovered by ALMA

    NASA Astrophysics Data System (ADS)

    Abraham, Zulema; Falceta-Gonçalves, Diego; Beaklini, Pedro P. B.

    2014-08-01

    We report observations of η Carinae obtained with ALMA in the continuum of 100, 230, 280, and 660 GHz in 2012 November, with a resolution that varied from 2.''88 to 0.''45 for the lower and higher frequencies, respectively. The source is not resolved, even at the highest frequency; its spectrum is characteristic of thermal bremsstrahlung of a compact source, but different from the spectrum of optically thin wind. The recombination lines H42α, He42α, H40α, He40α, H50β, H28α, He28α, H21α, and He21α were also detected, and their intensities reveal non-local thermodynamic equilibrium effects. We found that the line profiles could only be fit by an expanding shell of dense and ionized gas, which produces a slow shock in the surroundings of η Carinae. Combined with fittings to the continuum, we were able to constrain the shell size, radius, density, temperature, and velocity. The detection of the He recombination lines is compatible with the high-temperature gas and requires a high-energy ionizing photon flux, which must be provided by the companion star. The mass-loss rate and wind velocity, necessary to explain the formation of the shell, are compatible with an luminous blue variable eruption. The position, velocity, and physical parameters of the shell coincide with those of the Weigelt blobs. The dynamics found for the expanding shell correspond to matter ejected by η Carinae in 1941 in an event similar to that which formed the Little Homunculus; for that reason, we called the new ejecta the "Baby Homunculus."

  16. η Carinae Baby Homunculus uncovered by ALMA

    SciTech Connect

    Abraham, Zulema; Beaklini, Pedro P. B.; Falceta-Gonçalves, Diego

    2014-08-20

    We report observations of η Carinae obtained with ALMA in the continuum of 100, 230, 280, and 660 GHz in 2012 November, with a resolution that varied from 2.''88 to 0.''45 for the lower and higher frequencies, respectively. The source is not resolved, even at the highest frequency; its spectrum is characteristic of thermal bremsstrahlung of a compact source, but different from the spectrum of optically thin wind. The recombination lines H42α, He42α, H40α, He40α, H50β, H28α, He28α, H21α, and He21α were also detected, and their intensities reveal non-local thermodynamic equilibrium effects. We found that the line profiles could only be fit by an expanding shell of dense and ionized gas, which produces a slow shock in the surroundings of η Carinae. Combined with fittings to the continuum, we were able to constrain the shell size, radius, density, temperature, and velocity. The detection of the He recombination lines is compatible with the high-temperature gas and requires a high-energy ionizing photon flux, which must be provided by the companion star. The mass-loss rate and wind velocity, necessary to explain the formation of the shell, are compatible with an luminous blue variable eruption. The position, velocity, and physical parameters of the shell coincide with those of the Weigelt blobs. The dynamics found for the expanding shell correspond to matter ejected by η Carinae in 1941 in an event similar to that which formed the Little Homunculus; for that reason, we called the new ejecta the 'Baby Homunculus'.

  17. Chilean Virtual Observatory services implementation for the ALMA public data

    NASA Astrophysics Data System (ADS)

    Antognini, Jonathan; Solar, Mauricio; Ibsen, Jorge; Araya, Mauricio; Nyman, Lars; Mardones, Diego; Valenzuela, Camilo; Ramirez, Patricio; Fernandez, Christopher; Garces, Mario

    2014-07-01

    The success of an observatory is usually measured by its impact in the scientific community, so a common objective is to provide transparent ways to access the generated data. The Chilean Virtual Observatory (ChiVO), started working in the implementation of a prototype, in collaboration with ALMA, considering the current needs of the Chilean astronomical community, in addition to the protocols and standards of IVOA, and the comparison of different existing data access toolkit services. Based on this efforts, a VO prototype was designed and implemented for the ALMA large scale of data.

  18. Synergies with ALMA and mm/submm facilities

    NASA Astrophysics Data System (ADS)

    Russell, H.; McNamara, B.; Fabian, A.

    2016-06-01

    New sub-mm facilities, such as ALMA, have opened up exciting new areas of astrophysics. I will review some of ALMA's exciting discoveries from the first five years of science including observations of massive molecular gas flows at the centres of nearby galaxies. Feedback from a central active galactic nucleus is thought to regulate the growth of massive galaxies by suppressing gas cooling and star formation. I will also focus on the potential contribution that XMM-Newton observations could make to these fields over the next decade.

  19. Circumnuclear molecular gas in M87 detected with ALMA

    NASA Astrophysics Data System (ADS)

    Vlahakis, Catherine E.

    2016-01-01

    We present the detection of circumnuclear molecular gas residing within 100 pc of the supermassive black hole (SMBH) in the galaxy M87 (3C 274), using the Atacama Large Millimeter/submillimeter Array (ALMA) to image the gas on spatial scales from 100 to 10 pc. The proximity of M87, the archetypical giant elliptical radio galaxy at the centre of the Virgo galaxy cluster, presents a unique opportunity to investigate in detail the circumnuclear molecular gas revealed first by single-dish observations and recently imaged for the first time with ALMA (Vlahakis et al., in prep). ALMA's unique long baseline capability now allows us to make the first detailed investigation of the properties of the interstellar medium around the galaxy's SMBH on scales down to 10 pc (0.1 arcsec). Here, we present results of ALMA Band 3 CO J=1-0 observations obtained at different angular resolutions. With this data we are able to trace the bulk of the molecular gas as well as the continuum emission, providing the deepest and highest spatial resolution images yet of the molecular gas content of this giant elliptical galaxy. The highest resolution data allow us to unambiguously resolve the molecular gas structures for the first time and investigate, in unprecedented detail, the nature and origin of molecular gas that resides within the sphere of influence of the SMBH.

  20. Alma Flor Ada and the Quest for Change

    ERIC Educational Resources Information Center

    Manna, Anthony, L.; Hill, Janet; Kellogg, Kathy

    2004-01-01

    Alma Flor Ada, a folklorist, novelist, scholar, teacher, and children's book author has passionate dedication to education for social justice, equality, and peace. As a faculty member at the University of San Francisco, Ada has developed programs that help students and others transform their lives and has written several bilingual legends and…

  1. THE 2014 ALMA LONG BASELINE CAMPAIGN: AN OVERVIEW

    SciTech Connect

    Partnership, ALMA; Fomalont, E. B.; Vlahakis, C.; Corder, S.; Remijan, A.; Barkats, D.; Dent, W. R. F.; Phillips, N.; Cox, P.; Hales, A. S.; Lucas, R.; Hunter, T. R.; Brogan, C. L.; Amestica, R.; Cotton, W.; Asaki, Y.; Matsushita, S.; Hills, R. E.; Richards, A. M. S.; Broguiere, D.; and others

    2015-07-20

    A major goal of the Atacama Large Millimeter/submillimeter Array (ALMA) is to make accurate images with resolutions of tens of milliarcseconds, which at submillimeter (submm) wavelengths requires baselines up to ∼15 km. To develop and test this capability, a Long Baseline Campaign (LBC) was carried out from 2014 September to late November, culminating in end-to-end observations, calibrations, and imaging of selected Science Verification (SV) targets. This paper presents an overview of the campaign and its main results, including an investigation of the short-term coherence properties and systematic phase errors over the long baselines at the ALMA site, a summary of the SV targets and observations, and recommendations for science observing strategies at long baselines. Deep ALMA images of the quasar 3C 138 at 97 and 241 GHz are also compared to VLA 43 GHz results, demonstrating an agreement at a level of a few percent. As a result of the extensive program of LBC testing, the highly successful SV imaging at long baselines achieved angular resolutions as fine as 19 mas at ∼350 GHz. Observing with ALMA on baselines of up to 15 km is now possible, and opens up new parameter space for submm astronomy.

  2. The 2014 ALMA Long Baseline Campaign: An Overview

    NASA Astrophysics Data System (ADS)

    ALMA Partnership; Fomalont, E. B.; Vlahakis, C.; Corder, S.; Remijan, A.; Barkats, D.; Lucas, R.; Hunter, T. R.; Brogan, C. L.; Asaki, Y.; Matsushita, S.; Dent, W. R. F.; Hills, R. E.; Phillips, N.; Richards, A. M. S.; Cox, P.; Amestica, R.; Broguiere, D.; Cotton, W.; Hales, A. S.; Hiriart, R.; Hirota, A.; Hodge, J. A.; Impellizzeri, C. M. V.; Kern, J.; Kneissl, R.; Liuzzo, E.; Marcelino, N.; Marson, R.; Mignano, A.; Nakanishi, K.; Nikolic, B.; Perez, J. E.; Pérez, L. M.; Toledo, I.; Aladro, R.; Butler, B.; Cortes, J.; Cortes, P.; Dhawan, V.; Di Francesco, J.; Espada, D.; Galarza, F.; Garcia-Appadoo, D.; Guzman-Ramirez, L.; Humphreys, E. M.; Jung, T.; Kameno, S.; Laing, R. A.; Leon, S.; Mangum, J.; Marconi, G.; Nagai, H.; Nyman, L.-A.; Radiszcz, M.; Rodón, J. A.; Sawada, T.; Takahashi, S.; Tilanus, R. P. J.; van Kempen, T.; Vila Vilaro, B.; Watson, L. C.; Wiklind, T.; Gueth, F.; Tatematsu, K.; Wootten, A.; Castro-Carrizo, A.; Chapillon, E.; Dumas, G.; de Gregorio-Monsalvo, I.; Francke, H.; Gallardo, J.; Garcia, J.; Gonzalez, S.; Hibbard, J. E.; Hill, T.; Kaminski, T.; Karim, A.; Krips, M.; Kurono, Y.; Lopez, C.; Martin, S.; Maud, L.; Morales, F.; Pietu, V.; Plarre, K.; Schieven, G.; Testi, L.; Videla, L.; Villard, E.; Whyborn, N.; Zwaan, M. A.; Alves, F.; Andreani, P.; Avison, A.; Barta, M.; Bedosti, F.; Bendo, G. J.; Bertoldi, F.; Bethermin, M.; Biggs, A.; Boissier, J.; Brand, J.; Burkutean, S.; Casasola, V.; Conway, J.; Cortese, L.; Dabrowski, B.; Davis, T. A.; Diaz Trigo, M.; Fontani, F.; Franco-Hernandez, R.; Fuller, G.; Galvan Madrid, R.; Giannetti, A.; Ginsburg, A.; Graves, S. F.; Hatziminaoglou, E.; Hogerheijde, M.; Jachym, P.; Jimenez Serra, I.; Karlicky, M.; Klaasen, P.; Kraus, M.; Kunneriath, D.; Lagos, C.; Longmore, S.; Leurini, S.; Maercker, M.; Magnelli, B.; Marti Vidal, I.; Massardi, M.; Maury, A.; Muehle, S.; Muller, S.; Muxlow, T.; O'Gorman, E.; Paladino, R.; Petry, D.; Pineda, J. E.; Randall, S.; Richer, J. S.; Rossetti, A.; Rushton, A.; Rygl, K.; Sanchez Monge, A.; Schaaf, R.; Schilke, P.; Stanke, T.; Schmalzl, M.; Stoehr, F.; Urban, S.; van Kampen, E.; Vlemmings, W.; Wang, K.; Wild, W.; Yang, Y.; Iguchi, S.; Hasegawa, T.; Saito, M.; Inatani, J.; Mizuno, N.; Asayama, S.; Kosugi, G.; Morita, K.-I.; Chiba, K.; Kawashima, S.; Okumura, S. K.; Ohashi, N.; Ogasawara, R.; Sakamoto, S.; Noguchi, T.; Huang, Y.-D.; Liu, S.-Y.; Kemper, F.; Koch, P. M.; Chen, M.-T.; Chikada, Y.; Hiramatsu, M.; Iono, D.; Shimojo, M.; Komugi, S.; Kim, J.; Lyo, A.-R.; Muller, E.; Herrera, C.; Miura, R. E.; Ueda, J.; Chibueze, J.; Su, Y.-N.; Trejo-Cruz, A.; Wang, K.-S.; Kiuchi, H.; Ukita, N.; Sugimoto, M.; Kawabe, R.; Hayashi, M.; Miyama, S.; Ho, P. T. P.; Kaifu, N.; Ishiguro, M.; Beasley, A. J.; Bhatnagar, S.; Braatz, J. A., III; Brisbin, D. G.; Brunetti, N.; Carilli, C.; Crossley, J. H.; D'Addario, L.; Donovan Meyer, J. L.; Emerson, D. T.; Evans, A. S.; Fisher, P.; Golap, K.; Griffith, D. M.; Hale, A. E.; Halstead, D.; Hardy, E. J.; Hatz, M. C.; Holdaway, M.; Indebetouw, R.; Jewell, P. R.; Kepley, A. A.; Kim, D.-C.; Lacy, M. D.; Leroy, A. K.; Liszt, H. S.; Lonsdale, C. J.; Matthews, B.; McKinnon, M.; Mason, B. S.; Moellenbrock, G.; Moullet, A.; Myers, S. T.; Ott, J.; Peck, A. B.; Pisano, J.; Radford, S. J. E.; Randolph, W. T.; Rao Venkata, U.; Rawlings, M. G.; Rosen, R.; Schnee, S. L.; Scott, K. S.; Sharp, N. K.; Sheth, K.; Simon, R. S.; Tsutsumi, T.; Wood, S. J.

    2015-07-01

    A major goal of the Atacama Large Millimeter/submillimeter Array (ALMA) is to make accurate images with resolutions of tens of milliarcseconds, which at submillimeter (submm) wavelengths requires baselines up to ˜15 km. To develop and test this capability, a Long Baseline Campaign (LBC) was carried out from 2014 September to late November, culminating in end-to-end observations, calibrations, and imaging of selected Science Verification (SV) targets. This paper presents an overview of the campaign and its main results, including an investigation of the short-term coherence properties and systematic phase errors over the long baselines at the ALMA site, a summary of the SV targets and observations, and recommendations for science observing strategies at long baselines. Deep ALMA images of the quasar 3C 138 at 97 and 241 GHz are also compared to VLA 43 GHz results, demonstrating an agreement at a level of a few percent. As a result of the extensive program of LBC testing, the highly successful SV imaging at long baselines achieved angular resolutions as fine as 19 mas at ˜350 GHz. Observing with ALMA on baselines of up to 15 km is now possible, and opens up new parameter space for submm astronomy. .

  3. Development of high-accuracy pointing verification for ALMA antenna

    NASA Astrophysics Data System (ADS)

    Matsuzawa, Ayumu; Saito, Masao; Iguchi, Satoru; Nakanishi, Kouichiro; Saito, Hiro

    2014-07-01

    Pointing performance of a radio telescope antenna is important in radio astronomical observations to obtain accurate intensity of a target source. The pointing errors of the ALMA ACA antenna are required to be better than 0.6 arcsec rss, which corresponds to 1/10 and 1/20 of the field of view of the ALMA ACA 12-m and 7-m antenna at 950 GHz, respectively. The pointing verification measurements of the ACA antenna were performed using an Optical pointing telescope (OPT) mounted on the antenna backup structure at the ALMA Operations Site Facility at 2900m above the sea level. Pointing errors of these OPT measurements contain three different origins; originated from antenna, originated of atmosphere (optical seeing), and originated of OPT itself. In order to estimate pointing errors of the antenna origin, we need to subtract the components of optical seeing and OPT itself accurately, while we need to add components that cannot be measured in the OPT measurements. The ACA antenna verification test report demonstrated that all the ACA 7-m antenna meets pointing specification of ALMA. However, about one-third of datasets, values of estimated optical seeing is larger than measured pointing errors. We re-examined a procedure to estimate optical seeing, by investigating the property of optical seeing from the high-sampling OPT pointing measurements of long tracking a bright star for 15 minutes. Particularly, we examined the relation between optical seeing and sampling rate derived from Kolmogorov PSD. Our analysis indicated that the optical seeing at ALMA site may have been overestimated in the verification test. We present a new relation between optical seeing and sampling rate proportional to average wind velocity during measurement. We used this new relation to derive the optical seeing and as a result the number of datasets becomes half in which the optical seeing is larger than measured pointing errors. As a result, we successfully develop a new verification method of

  4. ALMA to Help Solving Acute Mountain Sickness Mystery

    NASA Astrophysics Data System (ADS)

    2007-04-01

    The Atacama Large Millimeter/submillimeter Array (ALMA) astronomical project will not only enlarge our knowledge of the vast Universe beyond the imaginable. It will also help scientists learn more about the human body. Located 5000m above sea level, in the Chilean Atacama desert, ALMA is the highest site for ground-based astronomy. This property will be put to good use for academic institutions in Chile and in Europe in order to study the human response to extreme altitude conditions. During a ceremony held on 2 April in Antofagasta, the largest town close to ESO's Very Large Telescope, representatives from ALMA, ESO and the University of Antofagasta have officially launched a collaborative agreement that also involves the University of Chile and the University of Copenhagen (Denmark). The newly established cooperation aims at contributing to the promotion of teaching, scientific research, and the expansion of altitude physiology and medicine or other related areas considered appropriate. ESO PR Photo 20/07 ESO PR Photo 20/07 Working at 5000 metres "An increasing number of people are periodically exposed to brisk changes in altitude, and not only for astronomical research," said Jacques Lassalle, the ALMA Safety Manager. "Short stays at high altitude alternate with short stays at sea level but the corresponding shifts are very often established by agreement, and not based on scientific arguments. With this project, we aim at improving our knowledge and procedures in order to protect the long term health of the operators, engineers, and scientists as well as ALMA visitors of all ages and all physical conditions," he added. Around the world, a large number of people systematically commute between sea level and high altitude, for example when working in mountainous mines. This poses stringent conditions that may affect health, wellbeing and working performance. Some of the factors in question are the shift work regime, the perturbation of circadian rhythms, fatigue

  5. U.S., European ALMA Partners Award Prototype Antenna Contracts

    NASA Astrophysics Data System (ADS)

    2000-03-01

    The U.S. and European partners in the Atacama Large Millimeter Array (ALMA) project have awarded contracts to U.S. and Italian firms, respectively, for two prototype antennas. ALMA is a planned telescope array, expected to consist of 64 millimeter-wave antennas with 12-meter diameter dishes. The array will be built at a high-altitude, extremely dry mountain site in Chile's Atacama desert, and is scheduled to be completed sometime in this decade. On February 22, 2000, Associated Universities Inc. (AUI) signed an approximately $6.2 million contract with Vertex Antenna Systems, of Santa Clara, Calif., for construction of one prototype ALMA antenna. AUI operates the U.S. National Radio Astronomy Observatory (NRAO) for the National Science Foundation under a cooperative agreement. The European partners contracted with the consortium of European Industrial Engineering and Costamasnaga, of Mestre, Italy, on February 21, 2000, for the production of another prototype. (Mestre is located on the inland side of Venice.) The two antennas must meet identical specifications, but will inherently be of different designs. This will ensure that the best possible technologies are incorporated into the final production antennas. Only one of the designs will be selected for final production. Several technical challenges must be met for the antennas to perform to ALMA specifications. Each antenna must have extremely high surface accuracy (25 micrometers, or one-third the diameter of a human hair, over the entire 12-meter diameter). This means that, when completed, the surface accuracy of the ALMA dishes will be 20 times greater than that of the Very Large Array (VLA) antennas, and about 50 times greater than dish antennas for communications or radar. The ALMA antennas must also have extremely high pointing accuracy (0.6 arcseconds). An additional challenge is that the antennas, when installed at the ALMA site in Chile, will be exposed to the ravages of weather at 16,500 feet (5000 meters

  6. National Academy of Sciences Recommends Continued Support of ALMA Project

    NASA Astrophysics Data System (ADS)

    2000-05-01

    A distinguished panel of scientists today announced their support for the continued funding of the Atacama Large Millimeter Array (ALMA) Project at a press conference given by the National Academy of Sciences. The ALMA Project is an international partnership between U.S. and European astronomy organizations to build a complete imaging telescope that will produce astronomical images at millimeter and submillimeter wavelengths. The U.S. partner is the National Science Foundation, through Associated Universities, Inc., (AUI), led by Dr. Riccardo Giacconi, and the National Radio Astronomy Observatory (NRAO). "We are delighted at this show of continued support from our peers in the scientific community," said Dr. Robert Brown, ALMA U.S. Project Director and Deputy Director of NRAO. "The endorsement adds momentum to the recent strides we've made toward the building of this important telescope." In 1998, the National Research Council, the working arm of the National Academy of Sciences, charged the Astronomy and Astrophysics Survey Committee to "survey the field of space- and ground-based astronomy and astrophysics" and to "recommend priorities for the most important new initiatives of the decade 2000-2010." In a report released today, the committee wrote that it "re-affirms the recommendations of the 1991 Astronomy and Astrophysics Survey Committee by endorsing the completion of . . . the Millimeter Array (MMA, now part of the Atacama Large Millimeter Array)." In the 1991 report "The Decade of Discovery," a previous committee chose the Millimeter Array as one of the most important projects of the decade 1990-2000. Early last year, the National Science Foundation signed a Memorandum of Understanding with a consortium of European organizations that effectively merged the MMA Project with the European Large Southern Array project. The combined project was christened the Atacama Large Millimeter Array. ALMA, expected to consist of 64 antennas with 12-meter diameter dishes

  7. New Inspiring Planetarium Show Introduces ALMA to the Public

    NASA Astrophysics Data System (ADS)

    2009-03-01

    As part of a wide range of education and public outreach activities for the International Year of Astronomy 2009 (IYA2009), ESO, together with the Association of French Language Planetariums (APLF), has produced a 30-minute planetarium show, In Search of our Cosmic Origins. It is centred on the global ground-based astronomical Atacama Large Millimeter/submillimeter Array (ALMA) project and represents a unique chance for planetariums to be associated with the IYA2009. ESO PR Photo 09a/09 Logo of the ALMA Planetarium Show ESO PR Photo 09b/09 Galileo's first observations with a telescope ESO PR Photo 09c/09 The ALMA Observatory ESO PR Photo 09d/09 The Milky Way band ESO PR Video 09a/09 Trailer in English ALMA is the leading telescope for observing the cool Universe -- the relic radiation of the Big Bang, and the molecular gas and dust that constitute the building blocks of stars, planetary systems, galaxies and life itself. It is currently being built in the extremely arid environment of the Chajnantor plateau, at 5000 metres altitude in the Chilean Andes, and will start scientific observations around 2011. ALMA, the largest current astronomical project, is a revolutionary telescope, comprising a state-of-the-art array of 66 giant 12-metre and 7-metre diameter antennas observing at millimetre and submillimetre wavelengths. In Search of our Cosmic Origins highlights the unprecedented window on the Universe that this facility will open for astronomers. "The show gives viewers a fascinating tour of the highest observatory on Earth, and takes them from there out into our Milky Way, and beyond," says Douglas Pierce-Price, the ALMA Public Information Officer at ESO. Edited by world fulldome experts Mirage3D, the emphasis of the new planetarium show is on the incomparable scientific adventure of the ALMA project. A young female astronomer guides the audience through a story that includes unique animations and footage, leading the viewer from the first observations by Galileo

  8. The Future of Astronomy and the ALMA Archive

    NASA Astrophysics Data System (ADS)

    Stoehr, F.; Lacy, M.; Leon, S.; Muller, E.; Kawamura, A.

    2015-09-01

    Astronomy is changing as the amount and complexity of data taken grows. We argue that in the future observatories will compete for astronomers to work with their data, that observatories will have to reorient themselves to from providing good data only to providing an excellent end-to-end user-experience with all its implications, that science-grade data-reduction pipelines will become an integral part of the design of a new observatory or instrument and that all this evolution will have a deep impact on how astronomers will do science. We show how ALMA's general design principles are in line with this paradigm and how the ALMA archive fits into this picture.

  9. Design and Characterization of the ALMA Band 5 Vacuum Window

    NASA Astrophysics Data System (ADS)

    Schroder, Arne; Murk, Axel; Yagoubov, Pavel; Patt, Ferdinand

    2016-01-01

    This paper summarizes the electromagnetic design process of the vacuum window for the Atacama Large Millimeter/sub-millimeter Array (ALMA) Band 5 (163-211 GHz). We have carried out investigations by means of numerical simulations as well as reflection and transmission measurements. Simulations were performed using the finite element method, an efficient quasi-analytical technique, and rigorous coupled-wave analysis. We used an injection-molded vacuum window prototype as a starting point of the design process and investigated deterioration in the electromagnetic performance caused by different types of manufacturing artifacts. Following these analyses, an optimization of the window has been performed based on simulations. We measured the reflectivity and transmittance of the newly designed window and this paper demonstrates that the optimized window exhibits a return loss better than -20 dB, as required by the ALMA specifications.

  10. Development of ALMA process: Advances maleic anhydride production technology

    SciTech Connect

    Arnoia, S.C.; Komeya, M.; Pedretti, D.; Stanecki, J.W.

    1987-01-01

    Shin-Daikyowa Petrochemical Co. (SDPC) has initiated a project to build a 15,000 MTA maleic anhydride plant at Yokkaichi, Japan. For technology, SDPC evaluated many alternatives and elected to utilize the ALMA Process in what will be the first full-scale plant for this new process. Startup is scheduled for late 1988. This paper describes the economic advantages of the ALMA Process and their technical bases which have led to its selection by SDPC. The advantages are in variable costs (primarily feed and energy) for any size plant, and in initial capital as well for plants larger than 10,000 MTA. They are derived from the use of n-butane feed, a fluidized-bed reactor system, and a non-aqueous recovery system.

  11. The ALMA assembly, integration, and verification project: a retrospective analysis

    NASA Astrophysics Data System (ADS)

    Lopez, B.; Knee, L. B. G.; Jager, H.; Whyborn, N.; McMullin, J.; Murowinski, R.; Peck, A.; Corder, S.

    2014-08-01

    The Atacama Large Millimeter/submillimeter Array (ALMA) is a joint project between astronomical organizations in Europe, North America, and East Asia, in collaboration with the Republic of Chile. ALMA consists of 54 twelve-meter antennas and 12 seven-meter antennas operating as an aperture synthesis array in the (sub)millimeter wavelength range. Assembly, Integration, and Verification (AIV) of the antennas was completed at the end of the year 2013, while the final optimization and complete expansion to validate all planned observing modes will continue. This paper compares the actually obtained results of the period 2008-2013 with the baselines that had been laid out in the early project-planning phase (2005-2007). First plans made for ALMA AIV had already established a two-phased project life-cycle: phase 1 for setting up necessary infrastructure and common facilities, and taking the first three antennas to the start of commissioning; and phase 2 focused on the steady state processing of the remaining units. Throughout the execution of the project this lifecycle was refined and two additional phases were added, namely a transition phase between phases 1 and 2, and a closing phase to address the project ramp-down. A sub-project called Accelerated Commissioning and Science Verification (ACSV) was carried out during the year 2009 in order to provide focus to the whole ALMA organization, and to accomplish the start-of-commissioning milestone. Early phases of CSV focused on validating the basic performance and calibration. Over time additional observing modes have been validated as capabilities expanded both in hardware and software. This retrospective analysis describes the originally presented project staffing plans and schedules, the underlying assumptions, identified risks and operational models, among others. For comparison actual data on staffing levels, the resultant schedule, additional risks identified and those that actually materialized, are presented. The

  12. Protoplanet Hunting with ALMA Observations of Molecular Emission

    NASA Astrophysics Data System (ADS)

    Cleeves, Ilse

    2016-05-01

    Young, luminous protoplanets embedded in circumstellar disks directly heat their local environment. The accretion luminosity from the planet can sublimate ices in its immediate vicinity, creating a unique gas-phase signature in the parent disk. We modeled the 3D chemical structure induced by planet-heating and find the ice sublimation is detectable by ALMA, and will follow the planet in its orbit.

  13. Revealing the dynamics of Class 0 protostellar discs with ALMA

    NASA Astrophysics Data System (ADS)

    Seifried, D.; Sánchez-Monge, Á.; Walch, S.; Banerjee, R.

    2016-06-01

    We present synthetic ALMA observations of Keplerian, protostellar discs in the Class 0 stage studying the emission of molecular tracers like 13CO, C18O, HCO+, H13CO+, N2H+, and H2CO. We model the emission of discs around low- and intermediate-mass protostars. We show that under optimal observing conditions ALMA is able to detect the discs already in the earliest stage of protostellar evolution, although the emission is often concentrated to the innermost 50 au. Therefore, a resolution of a few 0.1 arcsec might be too low to detect Keplerian discs around Class 0 objects. We also demonstrate that under optimal conditions for edge-on discs Keplerian rotation signatures are recognisable, from which protostellar masses can be inferred. For this we here introduce a new approach, which allows us to determine protostellar masses with higher fidelity than before. Furthermore, we show that it is possible to reveal Keplerian rotation even for strongly inclined discs and that ALMA should be able to detect possible signs of fragmentation in face-on discs. In order to give some guidance for future ALMA observations, we investigate the influence of varying observing conditions and source distances. We show that it is possible to probe Keplerian rotation in inclined discs with an observing time of 2 h and a resolution of 0.1 arcsec, even in the case of moderate weather conditions. Furthermore, we demonstrate that under optimal conditions, Keplerian discs around intermediate-mass protostars should be detectable up to kpc distances.

  14. Final tests and performances verification of the European ALMA antennas

    NASA Astrophysics Data System (ADS)

    Marchiori, Gianpietro; Rampini, Francesco

    2012-09-01

    The Atacama Large Millimeter Array (ALMA) is under erection in Northern Chile. The array consists of a large number (up to 64) of 12 m diameter antennas and a number of smaller antennas, to be operated on the Chajnantor plateau at 5000 m altitude. The antennas will operate up to 950 GHz so that their mechanical performances, in terms of surface accuracy, pointing precision and dimensional stability, are very tight. The AEM consortium constituted by Thales Alenia Space France, Thales Alenia Space Italy, European Industrial Engineering (EIE GROUP), and MT Mechatronics is assembling and testing the 25 antennas. As of today, the first set of antennas have been delivered to ALMA for science. During the test phase with ESO and ALMA, the European antennas have shown excellent performances ensuring the specification requirements widely. The purpose of this paper is to present the different results obtained during the test campaign: surface accuracy, pointing error, fast motion capability and residual delay. Very important was also the test phases that led to the validation of the FE model showing that the antenna is working with a good margin than predicted at design level thanks also to the assembly and integration techniques.

  15. ALMA Binary Data Transport Mechanism using VOTable Headers

    NASA Astrophysics Data System (ADS)

    Wicenec, A.; Meuss, H.; Pisano, J.

    2006-07-01

    ALMA will produce very large data rates and volumes. In full operation the correlator will generate up to 60 MB/s of visibility data. These data have to be transported from the correlator on the high site (5000 m) to the ALMA archive, the telescope calibration and the quick-look subsystems, which are all located at the low site (2500 m) some 40 km away. A dedicated fiber connection between the sites is under construction and the interfaces between the subsystems are under development. The actual transport format produced by the correlator has been defined and implemented and is described in this paper in more detail. The format is derived from the SOAP with attachments [1], but instead of the SOAP XML envelope it is using a slightly modified VOTable [2] to keep the description of the binary data. The VOTable uses content ID pointers (CID, RFC2111 [3]) to refer to the binary parts contained in the same Multipart/Related (RFC2387 [4]) container. Such Multipart/Related containers are constructed for each ALMA integration and sent through a multimedia streaming connection implemented in CORBA (TAO[5, 6]).

  16. ALMA test interferometer control system: past experiences and future developments

    NASA Astrophysics Data System (ADS)

    Marson, Ralph G.; Pokorny, Martin; Kern, Jeff; Stauffer, Fritz; Perrigouard, Alain; Gustafsson, Birger; Ramey, Ken

    2004-09-01

    The Atacama Large Millimeter Array (ALMA) will, when it is completed in 2012, be the world's largest millimeter & sub-millimeter radio telescope. It will consist of 64 antennas, each one 12 meters in diameter, connected as an interferometer. The ALMA Test Interferometer Control System (TICS) was developed as a prototype for the ALMA control system. Its initial task was to provide sufficient functionality for the evaluation of the prototype antennas. The main antenna evaluation tasks include surface measurements via holography and pointing accuracy, measured at both optical and millimeter wavelengths. In this paper we will present the design of TICS, which is a distributed computing environment. In the test facility there are four computers: three real-time computers running VxWorks (one on each antenna and a central one) and a master computer running Linux. These computers communicate via Ethernet, and each of the real-time computers is connected to the hardware devices via an extension of the CAN bus. We will also discuss our experience with this system and outline changes we are making in light of our experiences.

  17. Observing turbulent fragmentation in simulations: predictions for CARMA and ALMA

    NASA Astrophysics Data System (ADS)

    Offner, Stella S. R.; Capodilupo, John; Schnee, Scott; Goodman, Alyssa A.

    2012-02-01

    Determining the initial stellar multiplicity is a challenging problem since protostars are faint and deeply embedded at early times; once formed, multiple protostellar systems may significantly dynamically evolve before they are optically revealed. Interferometers such as Combined Array for Research in Millimeter-wave Astronomy (CARMA) and Atacama Large Millimeter/submillimeter Array (ALMA) make it possible to probe the scales at which turbulent fragmentation occurs in dust continuum emission, potentially constraining early stellar multiplicity. In this Letter, we present synthetic observations of starless and protostellar cores undergoing fragmentation on scales of a few thousand astronomical units to produce wide binary systems. We show that interferometric observations of starless cores by CARMA should be predominantly featureless at early stages, although wide protostellar companions should be apparent. The enhanced capabilities of ALMA improve the detection of core morphology so that it may be possible to detect substructure at earlier times. In either case, spatial filtering from interferometry reduces the observed core substructure and often eradicates traces of existing filamentary morphology on scales down to 0.025 pc. However, some missing structure may be recaptured by combining data from the ALMA full science and Atacama compact arrays.

  18. ALMA to Help Solving Acute Mountain Sickness Mystery

    NASA Astrophysics Data System (ADS)

    2007-04-01

    The Atacama Large Millimeter/submillimeter Array (ALMA) astronomical project will not only enlarge our knowledge of the vast Universe beyond the imaginable. It will also help scientists learn more about the human body. Located 5000m above sea level, in the Chilean Atacama desert, ALMA is the highest site for ground-based astronomy. This property will be put to good use for academic institutions in Chile and in Europe in order to study the human response to extreme altitude conditions. During a ceremony held on 2 April in Antofagasta, the largest town close to ESO's Very Large Telescope, representatives from ALMA, ESO and the University of Antofagasta have officially launched a collaborative agreement that also involves the University of Chile and the University of Copenhagen (Denmark). The newly established cooperation aims at contributing to the promotion of teaching, scientific research, and the expansion of altitude physiology and medicine or other related areas considered appropriate. ESO PR Photo 20/07 ESO PR Photo 20/07 Working at 5000 metres "An increasing number of people are periodically exposed to brisk changes in altitude, and not only for astronomical research," said Jacques Lassalle, the ALMA Safety Manager. "Short stays at high altitude alternate with short stays at sea level but the corresponding shifts are very often established by agreement, and not based on scientific arguments. With this project, we aim at improving our knowledge and procedures in order to protect the long term health of the operators, engineers, and scientists as well as ALMA visitors of all ages and all physical conditions," he added. Around the world, a large number of people systematically commute between sea level and high altitude, for example when working in mountainous mines. This poses stringent conditions that may affect health, wellbeing and working performance. Some of the factors in question are the shift work regime, the perturbation of circadian rhythms, fatigue

  19. The Alma College Career Preparation Program. Final Report, October 1, 1977-December 31, 1978.

    ERIC Educational Resources Information Center

    Alma Coll., MI.

    A career preparation program (CPP) at Alma College, Alma, Michigan, intended to strengthen career planning services, add new programs supporting and augmenting liberal arts program strengths, more effectively integrate educational progress with plans to enter the world of work, and develop faculty career planning skills and liaison with business,…

  20. Observations of CO in Titan's Atmosphere Using ALMA

    NASA Astrophysics Data System (ADS)

    Serigano, Joseph; Nixon, Conor A.; Cordiner, Martin; Irwin, Patrick G. J.; Teanby, Nicholas; Charnley, Steven B.; Lindberg, Johan E.; Remijan, Anthony J.

    2015-11-01

    The advent of the Atacama Large Millimeter/submillimeter Array (ALMA) has provided a powerful facility for probing the atmospheres of solar system targets at long wavelengths (84-720 GHz) where the rotational lines of small, polar molecules are prominent. In the dense, nitrogen-dominated atmosphere of Titan, photodissociation of molecular nitrogen and methane leads to a wealth of complex hydrocarbons and nitriles in small abundances. Past millimeter/submillimeter observations, including ground-based observations as well as those by the Composite Infrared Spectrometer (CIRS) aboard the Cassini spacecraft, have proven the significance of this wavelength region for the derivation of vertical mixing profiles, latitudinal and seasonal variations, and molecular detections. Previous ALMA studies of Titan have presented mapping and vertical column densities of hydrogen isocyanide (HNC) and cyanoacetylene (HC3N) (Cordiner et al. 2014) as well as the first spectroscopic detection of ethyl cyanide (C2H5CN) in Titan’s atmosphere (Cordiner et al. 2015).Here, we report several submillimetric observations of carbon monoxide (CO) and its isotopologues 13CO, C18O, and C17O in Titan’s atmosphere obtained with flux calibration data from the ALMA Science Archive. We employ NEMESIS, a line-by-line radiative transfer code, to determine the stratospheric abundances of these molecules. The abundance of CO in Titan's atmosphere is determined to be approximately 50±1 ppm, constant with altitude, and isotopic ratios are determined to be approximately 12C/13C = 90, 16O/18O = 470, and 16O/17O = 2800. This report presents the first spectroscopic detection of C17O in the outer solar system, detected at >11σ confidence. This talk will focus on isotopic ratios in CO in Titan's atmosphere and will compare our results to previously measured values for Titan and other bodies in the Solar System. General implications for the history of Titan from measurements of CO and its isotopologues will be

  1. The ALMA common software: dispatch from the trenches

    NASA Astrophysics Data System (ADS)

    Schwarz, J.; Sommer, H.; Jeram, B.; Sekoranja, M.; Chiozzi, G.; Grimstrup, A.; Caproni, A.; Paredes, C.; Allaert, E.; Harrington, S.; Turolla, S.; Cirami, R.

    2008-07-01

    The ALMA Common Software (ACS) provides both an application framework and CORBA-based middleware for the distributed software system of the Atacama Large Millimeter Array. Building upon open-source tools such as the JacORB, TAO and OmniORB ORBs, ACS supports the development of component-based software in any of three languages: Java, C++ and Python. Now in its seventh major release, ACS has matured, both in its feature set as well as in its reliability and performance. However, it is only recently that the ALMA observatory's hardware and application software has reached a level at which it can exploit and challenge the infrastructure that ACS provides. In particular, the availability of an Antenna Test Facility(ATF) at the site of the Very Large Array in New Mexico has enabled us to exercise and test the still evolving end-to-end ALMA software under realistic conditions. The major focus of ACS, consequently, has shifted from the development of new features to consideration of how best to use those that already exist. Configuration details which could be neglected for the purpose of running unit tests or skeletal end-to-end simulations have turned out to be sensitive levers for achieving satisfactory performance in a real-world environment. Surprising behavior in some open-source tools has required us to choose between patching code that we did not write or addressing its deficiencies by implementing workarounds in our own software. We will discuss these and other aspects of our recent experience at the ATF and in simulation.

  2. Complementarity of NGST, ALMA, and Far IR Space Observatories

    NASA Technical Reports Server (NTRS)

    Mather, John C.

    2004-01-01

    The Next Generation Space Telescope (NGST) and the Atacama Large Millimeter Array (ALMA) will both start operations long before a new far IR observatory to follow SIRTF into space can be launched. What will be unknown even after they are operational, and what will a far IR space observatory be able to add? I will compare the telescope design concepts and capabilities and the advertised scientific programs for the projects and attempt to forecast the research topics that will be at the forefront in 2010.

  3. 12. VIEW OF WESTERN CANAL AT ALMA SCHOOL ROAD IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW OF WESTERN CANAL AT ALMA SCHOOL ROAD IN MESA, THE LOCATION AT WHICH THE PECK, PINE AND WALLACE FEEDERS FORMERLY JOINED TO FORM THE WESTERN CANAL. THE PECK AND PINE FEEDERS, NOW KNOWN AS LATERAL 9 AND LATERAL 10, AND ALMOST ENTIRELY PIPED, STILL JOIN THE WESTERN CANAL AT THIS POINT, BUT AN EQUALLY IMPORTANT SOURCE OF SUPPLY IS THE NUMEROUS GROUNDWATER PUMPS LOCATED ON THE SYSTEM. - Western Canal, South side of Salt River between Tempe, Phoenix & Mesa, Mesa, Maricopa County, AZ

  4. ALMA and the Future of Millimeter Imaging Observations

    NASA Astrophysics Data System (ADS)

    Wilner, David J.

    2016-01-01

    The Nearby Young Moving Groups sample the critical age when primordial disks around stars complete their transformation into planetary systems with associated debris. Millimeter wavelengths provide direct access to cool material in these circumstellar disks. The high angular resolution of interferometry at these long wavelengths enables resolved observations of solids in an optically thin regime, as well as the thermal, chemical, and dynamical structure of gas, if present. In this contribution, I briefly review the evolving landscape of millimeter telescopes, with emphasis on the revolutionary capabilities of the new international Atacama Large Millimeter/submillimeter Array (ALMA) and describe pertinent early science results.

  5. Evaluation of Amigas Latinas Motivando el Alma (ALMA): a pilot promotora intervention focused on stress and coping among immigrant Latinas.

    PubMed

    Tran, Anh N; Ornelas, India J; Perez, Georgina; Green, Melissa A; Lyn, Michelle; Corbie-Smith, Giselle

    2014-04-01

    Recent immigrant Latinas are at increased risk of poor mental health due to stressors associated with adapting to life in the United States. This study evaluated Amigas Latinas Motivando el Alma, a promotora intervention to reduce stress and promote health and coping among recent immigrant Latinas. Using a pre- and post-test design, we evaluated mental health outcomes, specifically, in promotoras. Promotoras' knowledge levels related to role of promotora and stress management increased, depressive symptoms and stress levels decreased, and coping responses and perceived social support increased as well. Results suggest that promotora programs may be an effective way to improve mental health in recent immigrant Latinas.

  6. A CORBA event system for ALMA common software

    NASA Astrophysics Data System (ADS)

    Fugate, David W.

    2004-09-01

    The ALMA Common Software notification channel framework provides developers with an easy to use, high-performance, event-driven system supported across multiple programming languages and operating systems. It sits on top of the CORBA notification service and hides nearly all CORBA from developers. The system is based on a push event channel model where suppliers push events onto the channel and consumers process these asynchronously. This is a many-to-many publishing model whereby multiple suppliers send events to multiple consumers on the same channel. Furthermore, these event suppliers and consumers can be coded in C++, Java, or Python on any platform supported by ACS. There are only two classes developers need to be concerned with: SimpleSupplier and Consumer. SimpleSupplier was designed so that ALMA events (defined as IDL structures) could be published in the simplest manner possible without exposing any CORBA to the developer. Essentially all that needs to be known is the channel's name and the IDL structure being published. The API takes care of everything else. With the Consumer class, the developer is responsible for providing the channel's name as well as associating event types with functions that will handle them.

  7. An overview of the ALMA Common Software (ACS) .

    NASA Astrophysics Data System (ADS)

    Di Marcantonio, P.; Cirami, R.; Caproni, A.; Chiozzi, G.; Jeram, B.; Sommer, H.; Harrington, S.; Zagar, K.; Plesko, M.; Sekoranja, M.

    The ALMA Common Software (ACS) is an application framework designed to provide a common and homogeneous software architecture and infrastructure, spanning the end to end needs of an Astronomical observatory, from the Telescope Control system to high-level data flow management. ACS offers, at the lower level, several basic services needed for object-oriented distributed computing like transparent remote object invocation, object deployment and location, distributed error, alarm handling, logging and events. On top of this it provides an application architecture based on the Component/Container paradigm that fosters sharing and reusing of software components. Although developed for the ALMA project, ACS is now used by several other projects worldwide, among which the Italian Sardinia Radio Telescope (SRT). Besides, there is an active community that shares ideas, concepts and actual software components. Major drivers for this diffusion were the choice of adopting the LGPL public license and the adoption of CORBA, a free but reliable and widely used middleware software. In this paper we present an overview of the main features of ACS, emphasizing in particular the role of INAF-OAT in this project.

  8. Container-component model and XML in ALMA ACS

    NASA Astrophysics Data System (ADS)

    Sommer, Heiko; Chiozzi, Gianluca; Zagar, Klemen; Voelter, Markus

    2004-09-01

    ALMA software, from high-level data flow applications down to instrument control, is built using the ACS framework. To meet the challenges of developing distributed software in distributed teams, ACS offers a container/component model that integrates the use of XML transfer objects. ACS containers are built on top of CORBA and are available for C++, Java, and Python, so that ALMA software can be written as components in any of these languages. The containers perform technical aspects of the software system, while components can focus on the implementation of functional requirements. Like Web services, components can use XML to exchange structured data by value. For Java components, the container seamlessly integrates the use of XML binding classes, which are Java classes that encapsulate access to XML data through type-safe methods. Binding classes are generated from XML schemas, allowing the Java compiler to enforce compliance of application code with the XML schemas. This presentation will explain the capabilities of the ACS container/component model, and how it relates to other middleware technologies that are popular in industry.

  9. Measuring Protoplanetary Disk Gas Surface Density Profiles with ALMA

    NASA Astrophysics Data System (ADS)

    Williams, Jonathan P.; McPartland, Conor

    2016-10-01

    The gas and dust are spatially segregated in protoplanetary disks due to the vertical settling and radial drift of large grains. A fuller accounting of the mass content and distribution in disks therefore requires spectral line observations. We extend the modeling approach presented in Williams & Best to show that gas surface density profiles can be measured from high fidelity 13CO integrated intensity images. We demonstrate the methodology by fitting ALMA observations of the HD 163296 disk to determine a gas mass, M gas = 0.048 M ⊙, and accretion disk characteristic size R c = 213 au and gradient γ = 0.39. The same parameters match the C18O 2–1 image and indicate an abundance ratio [12CO]/[C18O] of 700 independent of radius. To test how well this methodology can be applied to future line surveys of smaller, lower mass T Tauri disks, we create a large 13CO 2–1 image library and fit simulated data. For disks with gas masses 3–10 M Jup at 150 pc, ALMA observations with a resolution of 0.″2–0.″3 and integration times of ∼20 minutes allow reliable estimates of R c to within about 10 au and γ to within about 0.2. Economic gas imaging surveys are therefore feasible and offer the opportunity to open up a new dimension for studying disk structure and its evolution toward planet formation.

  10. Business Intelligence Applied to the ALMA Software Integration Process

    NASA Astrophysics Data System (ADS)

    Zambrano, M.; Recabarren, C.; González, V.; Hoffstadt, A.; Soto, R.; Shen, T.-C.

    2012-09-01

    Software quality assurance and planning of an astronomy project is a complex task, specially if it is a distributed collaborative project such as ALMA, where the development centers are spread across the globe. When you execute a software project there is much valuable information about this process itself that you might be able to collect. One of the ways you can receive this input is via an issue tracking system that will gather the problem reports relative to software bugs captured during the testing of the software, during the integration of the different components or even worst, problems occurred during production time. Usually, there is little time spent on analyzing them but with some multidimensional processing you can extract valuable information from them and it might help you on the long term planning and resources allocation. We present an analysis of the information collected at ALMA from a collection of key unbiased indicators. We describe here the extraction, transformation and load process and how the data was processed. The main goal is to assess a software process and get insights from this information.

  11. UNVEILING THE DUST NUCLEATION ZONE OF IRC+10216 WITH ALMA

    SciTech Connect

    Cernicharo, J.; Daniel, F.; Goicoechea, J. R.; Castro-Carrizo, A.; Guélin, M.; Agundez, M.; Marcelino, N.; Joblin, C.

    2013-12-01

    We report the detection in IRC+10216 of lines of HNC J = 3 – 2 pertaining to nine excited vibrational states with energies up to ∼5300 K. The spectrum, observed with ALMA, also shows a surprising large number of narrow, unidentified lines that arise in the vicinity of the star. The HNC data are interpreted through a 1D-spherical non-local radiative transfer model, coupled to a chemical model that includes chemistry at thermochemical equilibrium for the innermost regions and reaction kinetics for the external envelope. Although unresolved by the current early ALMA data, the radius inferred for the emitting region is ∼0.''06 (i.e., ≅ 3 stellar radii), similar to the size of the dusty clumps reported by IR studies of the innermost region (r < 0.''3). The derived abundance of HNC relative to H{sub 2} is 10{sup –8} < χ(HNC) <10{sup –6}, and drops quickly where the gas density decreases and the gas chemistry is dominated by reaction kinetics. Merging HNC data with that of molecular species present throughout the inner envelope, such as vibrationally excited HCN, SiS, CS, or SiO, should allow us to characterize the physical and chemical conditions in the dust formation zone.

  12. The Molecular Gas Outflow of NGC 1068 Imaged by ALMA

    NASA Astrophysics Data System (ADS)

    García-Burillo, S.

    2015-12-01

    We have used the ALMA array to map the emission of a set of dense molecular gas tracers (CO(3-2), CO(6-5), HCN(4-3), HCO+(4-3), and CS(7-6)) in the central r˜2 kpc of the Seyfert 2 galaxy NGC 1068 with spatial resolutions ˜0.3″-0.5″ (˜20-35 pc). The sensitivity and spatial resolution of ALMA give a detailed view of the distribution and kinematics of the dense molecular gas. The gas kinematics from r˜50 pc out to r˜400 pc reveal a massive outflow in all molecular tracers. The tight correlation between the ionized gas outflow, the radio jet, and the occurrence of outward motions in the disk suggests that the outflow is AGN driven. The outflow rate estimated in the CND, M/dt˜63+21-37 M⊙ yr-1, is an order of magnitude higher than the star formation rate at these radii. The molecular outflow could quench star formation in the inner r˜400 pc of the galaxy on short timescales of ≤1 Myr and regulate gas accretion in the CND.

  13. Simulating ALMA Observations of High-Redshift Submillimeter Galaxies

    NASA Astrophysics Data System (ADS)

    Carilli, Michael; Wagg, J.

    2007-12-01

    Until now, the coarse angular resolution of single-dish submm/mm telescopes has limited the depth of extragalactic surveys through confusion noise, meaning that only 20-30% of the 850 micron background can be resolved. However, the majority of this population should have flux densities of 1 mJy or fainter, and so either cannot be resolved or would require prohibitively long integration times to conduct surveys with existing interferometers. This will change with the advent of the Atacama Large Millimeter Array (ALMA); beginning operation within the next decade, it will provide an order of magnitude increase in sensitivity over that of current interferometers. To better plan for future surveys with this facility, I have prepared a set of simulated 850 micron and 1 mm maps covering 16 square arcminutes with an angular resolution of 1 arcsecond. The input models used to create these simulations are based on our current constraints on the 850 micron and 1 mm number counts, as well as a heuristic model which assumes an evolving 60 micron IRAS luminosity function. This work shows how ALMA will constrain the number counts well below the sub-mJy level. Research was conducted as part of the National Science Foundation's Research Experience for Undergraduates program.

  14. Isotopic Ratios in Nitrile Species on Titan using ALMA

    NASA Astrophysics Data System (ADS)

    Molter, Edward; Nixon, Conor; Cordiner, Martin; Serigano, Joseph; Irwin, Patrick; Teanby, Nicholas; Charnley, Steven; Lindeberg, Johan

    2016-06-01

    The atmosphere of Titan is primarily composed of molecular nitrogen (N2, ˜98%) and methane (CH4, ˜2%), but also hosts a myriad of trace organic species. Two of the simplest and most abundant of these are hydrogen cyanide (HCN) and cyanoacetylene (HC3N). The advent of ALMA provides the opportunity to observe rotational transitions in these molecules and their isotopologues with unprecendented sensitivity and spatial resolution. We searched through the ALMA archive for publicly available high-resolution observations of Titan as a flux calibrator source taken between April and July 2014; each integration lasted around 160 seconds. Using spectra of HCN and HC3N isotopologues found in these data, we derive vertical abundance profiles and determine the isotopic ratios 14N/15N and 12C/13C in these molecules. We also report the detection of a new HCN isotopologue on Titan, H13C6 15N, and use a high signal-to-noise spectrum of DCN to determine the D/H ratio in HCN on Titan for the first time. These isotopic ratios are leveraged to constrain the physical and chemical processes occurring in Titan's atmosphere.

  15. Molecular Spectroscopy and the Atacama Large Millimeter/submillimeter Array (alma)

    NASA Astrophysics Data System (ADS)

    Remijan, Anthony J.

    2009-06-01

    The next generation of powerful millimeter/submillimeter (e.g. ALMA, LMT & Herschel) and radio (GBT, NRAO's our most over-subscribed telescope, & eVLA) observatories require extensive resources to help identify and analyse spectral line transitions. The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of East Asia, Europe and North America in cooperation with the Republic of Chile. The North American ALMA Science Center (NAASC) in Charlottesville, Virginia, is responsible for supporting the science use of ALMA by the North American astronomical community (the USA via the NRAO and Canada via the National Research Council of Canada) and for research and development activities in support of future upgrades of ALMA. In this presentation, I will first present the current state of the ALMA project and the NAASC and second, the steps taken by the NA ALMA partners to address the spectroscopic needs of the observatory including project "Splatalogue". Finally, I will discuss the additional plans of the NAASC to provide tools for the analysis of spectroscopic products of the observatory, such as spectral line data cubes.

  16. OPTICAL–INFRARED PROPERTIES OF FAINT 1.3 mm SOURCES DETECTED WITH ALMA

    SciTech Connect

    Hatsukade, Bunyo; Yabe, Kiyoto; Ohta, Kouji; Seko, Akifumi; Makiya, Ryu; Akiyama, Masayuki

    2015-09-10

    We report optical-infrared (IR) properties of faint 1.3 mm sources (S{sub 1.3mm} = 0.2–1.0 mJy) detected with the Atacama Large Millimeter/submillimeter Array (ALMA) in the Subaru/XMM-Newton Deep Survey field. We searched for optical/IR counterparts of eight ALMA-detected sources (≥4.0σ, the sum of the probability of spurious source contamination is ∼1) in a K-band source catalog. Four ALMA sources have K-band counterpart candidates within a 0.″4 radius. Comparison between ALMA-detected and undetected K-band sources in the same observing fields shows that ALMA-detected sources tend to be brighter, more massive, and more actively forming stars. While many of the ALMA-identified submillimeter-bright galaxies (SMGs) in previous studies lie above the sequence of star-forming galaxies in the stellar mass–star formation rate plane, our ALMA sources are located in the sequence, suggesting that the ALMA-detected faint sources are more like “normal” star-forming galaxies rather than “classical” SMGs. We found a region where multiple ALMA sources and K-band sources reside in a narrow photometric redshift range (z ∼ 1.3–1.6) within a radius of 5″ (42 kpc if we assume z = 1.45). This is possibly a pre-merging system and we may be witnessing the early phase of formation of a massive elliptical galaxy.

  17. Astronomers Break Ground on Atacama Large Millimeter Array (ALMA) - World's Largest Millimeter Wavelength Telescope

    NASA Astrophysics Data System (ADS)

    2003-11-01

    Scientists and dignitaries from Europe, North America and Chile are breaking ground today (Thursday, November 6, 2003) on what will be the world's largest, most sensitive radio telescope operating at millimeter wavelengths . ALMA - the "Atacama Large Millimeter Array" - will be a single instrument composed of 64 high-precision antennas located in the II Region of Chile, in the District of San Pedro de Atacama, at the Chajnantor altiplano, 5,000 metres above sea level. ALMA 's primary function will be to observe and image with unprecedented clarity the enigmatic cold regions of the Universe, which are optically dark, yet shine brightly in the millimetre portion of the electromagnetic spectrum. The Atacama Large Millimeter Array (ALMA) is an international astronomy facility. ALMA is an equal partnership between Europe and North America, in cooperation with the Republic of Chile, and is funded in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC), and in Europe by the European Southern Observatory (ESO) and Spain. ALMA construction and operations are led on behalf of North America by the National Radio Astronomy Observatory (NRAO), which is managed by Associated Universities, Inc. (AUI), and on behalf of Europe by ESO. " ALMA will be a giant leap forward for our studies of this relatively little explored spectral window towards the Universe" , said Dr. Catherine Cesarsky , Director General of ESO. "With ESO leading the European part of this ambitious and forward-looking project, the impact of ALMA will be felt in wide circles on our continent. Together with our partners in North America and Chile, we are all looking forward to the truly outstanding opportunities that will be offered by ALMA , also to young scientists and engineers" . " The U.S. National Science Foundation joins today with our North American partner, Canada, and with the European Southern Observatory, Spain, and Chile to prepare

  18. Extending the Device Support for the ALMA Control Subsystem Code Generation Framework

    NASA Astrophysics Data System (ADS)

    Reveco, J.; Mora, M.; González, V.; Sáez, N.; Ibsen, J.; Staig, T.; Reyes, C.; Kern, J.; Juerges, T.

    2010-12-01

    The existing code generation framework in the ALMA Control subsystem provides basic and functional code for ALMA antenna devices using CAN bus as communication interface. There are also devices which use Ethernet communication. This paper explains how the code generation framework, based on openArchitectureWare, was extended to include the code generation of Ethernet control components, working on top of the ALMA Common Software (ACS) distributed control framework. In order to achieve this, a new datamodel and new class templates were created, and the device components design adapted.

  19. The 492 GHz emission of Sgr A* constrained by ALMA

    NASA Astrophysics Data System (ADS)

    Liu, Hauyu Baobab; Wright, Melvyn C. H.; Zhao, Jun-Hui; Mills, Elisabeth A. C.; Requena-Torres, Miguel A.; Matsushita, Satoki; Martín, Sergio; Ott, Jürgen; Morris, Mark R.; Longmore, Steven N.; Brinkerink, Christiaan D.; Falcke, Heino

    2016-09-01

    Aims: Our aim is to characterize the polarized continuum emission properties including intensity, polarization position angle, and polarization percentage of Sgr A* at ~492 GHz. This frequency, well into the submillimeter bump where the emission is supposed to become optically thin, allows us to see down to the event horizon. Hence the reported observations contain potentially vital information on black hole properties. We have compared our measurements with previous, lower frequency observations, which provides information in the time domain. Methods: We report continuum emission properties of Sgr A* at ~492 GHz, based on Atacama Large Millimeter Array (ALMA) observations. We measured flux densities of Sgr A* from the central fields of our ALMA mosaic observations. We used calibration observations of the likely unpolarized continuum emission of Titan and the observations of Ci line emission, to gauge the degree of spurious polarization. Results: The flux density of 3.6 ± 0.72 Jy which we measured during our run is consistent with extrapolations from previous, lower frequency observations. We found that the continuum emission of Sgr A* at ~492 GHz shows large amplitude differences between the XX and the YY correlations. The observed intensity ratio between the XX and YY correlations as a function of parallactic angle can be explained by a constant polarization position angle of ~158°± 3°. The fitted polarization percentage of Sgr A* during our observational period is 14% ± 1.2%. The calibrator quasar J1744-3116 we observed on the same night can be fitted to Stokes I = 252 mJy, with 7.9% ± 0.9% polarization at position angle PA = 14°± 4.2°. Conclusions: The observed polarization percentage and polarization position angle in the present work appear consistent with those expected from longer wavelength observations in the period of 1999-2005. In particular, the polarization position angle at 492 GHz expected from the previously fitted 167°± 7° intrinsic

  20. The ALMA Front-end Archive Setup and Performance

    NASA Astrophysics Data System (ADS)

    Wicenec, A.; Chen, A.; Checcucci, A.; Jeram, B.; Meuss, H.; Persson, A.; Burgos, P.; Cirami, R.

    2010-12-01

    The ALMA front-end archive system has to capture up to 64 MB/s for a period of several days plus the data of about 100,000 monitor points from all 66 antennas and the correlators. The main science data is delivered through corba based audio/video streams and finally stored on SATA disk arrays hosted on 6 computers and controlled by 12 daemons. All data is collected by software components running on computers in the antennas and then sent through dedicated fiber links to the Array Operations Site at 5000 m and from there to the Operations Support Facility (OSF) at 3000 m elevation. The various hardware and software components have been tuned and tested to be able to meet the performance requirements. This paper describes the setup and the various components in more detail and gives results of various test runs.

  1. Tiers of the maintenance concept at ALMA in operations

    NASA Astrophysics Data System (ADS)

    Rabanus, David

    2014-08-01

    The Atacama Large Millimeter/submillimeter Array finds itself in the transition into full operations. Previous construction activities are being wrapped up, and regular, repetitive maintenance and upkeep will dominate the daily life, which asks for a consolidation and streamlining of the activities at the observatory. Especially the shifting focus to the high site of the observatory deserves more attention, since assembly, integration and verification activities at the base camp have ceased by now. In parallel, adjustments in the host country's labor legislation for operations at high geographic altitudes demand a review of the way things are done. This talk outlines the underlying operational concepts, lists the limiting constraints, describes the implementation of our reactions to those, and outlines our future intentions, which will be one in a number of steps towards optimization of the productivity of the observatory. The latter is the top level goal, which the Joint ALMA Observatory (JAO) has signed up for.

  2. Radio measurements of constant variation, and perspectives with ALMA

    NASA Astrophysics Data System (ADS)

    Combes, Françoise

    2010-11-01

    In the radio domain, absorption lines in front of quasars of CO, HI, OH, HCO+, HCN, up to NH3 and CII are providing interesting constraints on fundamental constant variation (α and μ). With more absorbing systems, and a wider redshift range, they could be more competitive than optical studies. This could come with ALMA, with more than one order of magnitude in sensitivity. Up to now, at intermediate and high redshift, between z = 0.25 to z = 0.89, only four absorption lines systems have been detected in the millimeter range and a fifth system at 0.765, at the OH-18cm lines (Kanekar et al. 2005). Out of these 5 systems, 3 are intervening lensing galaxies (and the background quasar is multiply imaged), and 2 correspond to an absorption of the host (PKS1413+135, B3-1504+377, for an overview see Combes & Wiklind 1996; Wiklind & Combes 1994 to 1998). A global comparison of all molecular lines observed with the HI-21cm absorption lines in PKS1413 and B0218 systems, the two narrowest line systems, have given quite stringent constraints on y = α2 gp μ, Δ y/y = (-0.20 ± 0.44) 10-5 and Δ y/y = (-0.16 ± 0.54) 10-5 respectively (Murphy et al. 2001). The precision is comparable to the MM method (Murphy et al. 2003), with a limited number of absorbing systems. The high sensitivity if the NH3 inversion lines to variation in the μ ratio (Flambaum & Kozlov 2007) was used by Henkel et al. (2009) in a recent multi-line study of PKS1830 at z ~ 0.9, and Murphy et al. (2008) for B0218 at z ~ 0.7. They find a limit of Δμ/μ < 1.4 10-6 and Δμ/μ < 1.8 10-6 respectively. Clearly, the radio method suffers from the rarity of the objects, and the fact that they have not yet been discovered at high redshift. The main caveats are that the lines compared come from different molecules, which might have intrinsic velocity offsets, due to several reasons, chemistry, excitation, temperature, density etc. . . When very different frequencies are compared (HI to CO for instance), the

  3. Oskar Kokoschka and Alma Mahler: art as diary and as therapy.

    PubMed

    Blum, Harold P

    2011-01-01

    The Austrian artist, Oskar Kokoschka, had an affair with Alma Mahler, widow of the composer Gustav Mahler, 1912-1914. This affair profoundly influenced his life and art. His palette at first brightened, with thick brush strokes and flashes of light and dark, indicating his psychological and emotional lability. Painting what he did not or could not express in words, his art of this period can be understood as an intimate visual diary of the vicissitudes of his relationship with Alma Mahler. For Kokoschka his work became a form of art therapy, following the crushing loss of Alma Mahler and near fatal physical injuries sustained in World War I. His gradual recovery was associated with his extraordinary attachment to and destruction of a lifelike effigy of Alma Mahler, thereby working through childhood trauma.

  4. ALMA 1.3 mm observations of the Fomalhaut System

    NASA Astrophysics Data System (ADS)

    White, Jacob; Boley, Aaron C.; Ford, Eric B.; Payne, Matthew John; Dent, William; Corder, Stuartt

    2016-10-01

    We present ALMA Band 6 (1.3 mm) observations of Fomalhaut and its debris disk. Since the system is relatively close at 7.7 pc, it has been the target of numerous studies at multiple wavelengths, and can serve as a testbed for debris disk evolution models and planet-disk interactions. Outstanding issues that need to be resolved to properly characterize the debris include tightening constraints on the spectral index in the submm/mm regime and determining whether there is indeed excess over the stellar emission, indicating the presence of an inner debris disk or ring.These ALMA 1.3 mm observations provide the highest resolution observations to date of the mm grains the outer ring. Tight constraints are placed on the geometry of the disk and on the mm-wavelength spectral index. We explore fitting the debris disk model in the image plane in addition to the standard method of fitting the visibilities. The results are compared and potential advantages/disadvantages of each approach are discussed.The central emission detected is indistinguishable from a point source, with 0.89 mJy being the best fit flux of the host star for Fomalhaut itself. This implies that any inner debris component must contribute little to the total central emission. Moreover, the stellar flux is less than 70% of that predicted by extrapolating a blackbody from the constrained photosphere temperature and just over 70% of the flux if extrapolating from the far infrared. This behavior is similar to that seen in the Sun for submm/mm wavelengths, but even more pronounced. Currently, insufficient data exists to properly constrain the degree to which stellar atmospheres affect the observed flux in the submm/mm regime. This result is part of an ongoing larger project focused on measuring the emission from stellar atmospheres at submm/mm wavelengths, which directly impacts inferred excesses for debris disk studies.

  5. Goodbye to WIMPs: A Scalable Interface for ALMA Operations

    NASA Astrophysics Data System (ADS)

    Schwarz, J.; Pietriga, E.; Schilling, M.; Grosbol, P.

    2011-07-01

    The operators of the ALMA Observatory will monitor and control more than 50 mm/submm radio antennas and their associated instrumentation from an operations site that is separated from this hardware by 35-50 km. Software that enables them to identify trouble spots and react to failures quickly in this environment will be critical to the safe and efficient functioning of the observatory. Early commissioning of ALMA uses a operator interface implemented with a standard window, icon, menu, pointing device (WIMP) toolkit. Early experience indicates that this paradigm will not scale well as the number of antennas approaches its full complement. Operators lose time as they manipulate overlapping or tabbed windows to drill-down to detailed diagnostic data, losing a feeling for "where they are" in the process. The WIMP model reaches its limits when there is so much information to present to users that they cannot focus on details while maintaining a view from above. To simplify the operators' tasks and let them concentrate on the real issues at hand rather than continually re-organizing their use of screen space, we are replacing the existing top-level interface with a multi-scale interface that takes advantage of semantic zooming, dynamic network visualization and other advanced filtering, navigation and visualization features. Following the first of several planned participatory design workshops, we have developed prototypes to show how users' needs can be met with the kinds of navigation that become possible when the restrictions of the WIMP model are lifted. Cycles of design and implementation coupled with active user feedback will characterize this project up through deployment.

  6. ALMA Observations of HD 141569’s Circumstellar Disk

    NASA Astrophysics Data System (ADS)

    White, J. A.; Boley, A. C.; Hughes, A. M.; Flaherty, K. M.; Ford, E.; Wilner, D.; Corder, S.; Payne, M.

    2016-09-01

    We present ALMA band 7 (345 GHz) continuum and 12CO(J = 3-2) observations of the circumstellar disk surrounding HD 141569. At an age of about 5 Myr, the disk has a complex morphology that may be best interpreted as a nascent debris system with gas. Our 870 μm ALMA continuum observations resolve a dust disk out to approximately 56 au from the star (assuming a distance of 116 pc) with 0.″38 resolution and 0.07 mJy beam-1 sensitivity. We measure a continuum flux density for this inner material of 3.8 ± 0.4 mJy (including calibration uncertainties). The 12CO(3-2) gas is resolved kinematically and spatially from about 30 to 210 au. The integrated 12CO(3-2) line flux density is 15.7 ± 1.6 Jy km s-1. We estimate the mass of the millimeter debris and 12CO(3-2) gas to be ≳0.04 M ⊕ and ˜2 × 10-3 M ⊕, respectively. If the millimeter grains are part of a collisional cascade, then we infer that the inner disk (<50 au) has ˜160 M ⊕ contained within objects less than 50 km in radius, depending on the planetesimal size distribution and density assumptions. Markov Chain Monte Carlo modeling of the system reveals a disk morphology with an inclination of 53.°4 centered around an M = 2.39 M ⊙ host star (Msin(i) = 1.92 M ⊙). We discuss whether the gas in HD 141569's disk may be second generation. If it is, the system can be used to study the clearing stages of planet formation.

  7. Molecular line emission in NGC 1068 imaged with ALMA

    NASA Astrophysics Data System (ADS)

    Garcia-Burillo, S.

    2015-09-01

    We investigate the fueling and the feedback of star formation and nuclear activity in NGC1068, a nearby Seyfert 2 barred galaxy, by analyzing the distribution and kinematics of the molecular gas in the disk. We have used ALMA to map the emission of a set of dense molecular gas tracers and their underlying continuum emission in the central r=2 kpc of NGC1068 with spatial resolutions 0.3"-0.5" (20-35 pc). Molecular line and dust continuum emissions are detected from a r=200 pc off-centered circumnuclear disk (CND), from the 2.6 kpc-diameter bar region, and from the r=1.3 kpc starburst (SB) ring. We used the dust continuum fluxes measured by ALMA together with NIR/MIR data to constrain the properties of the putative torus using CLUMPY models and found a torus radius of 20(6,-10)pc. The gas kinematics from r=50 pc out to r=400 pc reveal a massive outflow in all molecular tracers. The tight correlation between the ionized gas outflow, the radio jet and the occurrence of outward motions in the disk suggests that the outflow is AGN-driven. The outflow rate estimated in the CND, dM/dt=63(21,-37)M(sun)/yr, is an order of magnitude higher than the star formation rate at these radii, confirming that the outflow is AGN-driven. The power of the AGN is able to account for the estimated momentum and kinetic luminosity of the outflow. The CND mass load rate of the CND outflow implies a very short gas depletion time scale of 1 Myr.

  8. Submillimeter mapping of mesospheric minor species on Venus with ALMA

    NASA Astrophysics Data System (ADS)

    Encrenaz, Therese; Moreno, Raphael; Moullet, Arielle; Lellouch, Emmanuel; Fouchet, Thierry

    2014-05-01

    ALMA offers a unique opportunity to map mesospheric species on Venus. During Cycle 0, we have observed Venus on November 14 and 15, 2011, using the compact configuration of ALMA. The diameter of Venus was 11 arcsec and the illumination factor was about 90 percent. Maps of CO, SO, SO2, and HDO have been built from transitions recorded in the 335-347 GHz frequency range. The mesospheric thermal profile has been inferred using the CO transition at 345.795 GHz. From the integrated spectrum of SO recorded on Nov. 14 at 346.528 GHz, we find that the best fit is obtained with a cut-off in the SO vertical distribution at about 88 km and a mean mixing ratio of about 8.0 ppb above this level. In the case of SO2, as for SO, we find that the best fit is obtained with a cut-off at about 88 km; the SO2 mixing ratio above this level is about 12 ppb. The map of HDO is retrieved from the 335.395 GHz transition. Assuming a typical D/H ratio of 200 times the terrestrial value in the mesosphere of Venus, we find that the disk averaged HDO spectrum is consistent with a H2O mixing ratio of about 2.5 ppm, constant with altitude. Our results are in good agreement with previous single dish submillimeter observations (Sandor and Clancy, Icarus 177, 129, 2005; Gurwell et al. Icarus 188, 288, 2007; Sandor et al. Icarus 208, 49, 2010; Icarus 217, 836, 2012), as well as with the predictions of photochemical models (Zhang et al. Icarus 217, 714, 2012).

  9. JCMT in the Post-Herschel ERA of Alma

    NASA Astrophysics Data System (ADS)

    Johnstone, Doug

    2013-07-01

    The James Clerk Maxwell Telescope (JCMT), with a 15m dish, is the largest single-dish astronomical telescope in the world designed specifically to operate in the sub-mm wavelength regime. The JCMT is located close to the summit of Mauna Kea, Hawaii, at an altitude of 4092m. The most recent addition to the JCMT's suite of instruments is the 10,000 bolometer sub-mm continuum instrument: SCUBA-2. SCUBA-2 operates simultaneously with 7' x7' foot print sub-arrays at both 450 and 850-microns. SCUBA-2's wide field surveying potential, combined with a 65% shared view of the sky from both sites, makes it the ideal instrument to provide complementary data for the ALMA Project. Furthermore, the SCUBA-2 sub-millimetre wavelength coverage and angular resolution complement existing Herschel observations. A set of comprehensive surveys of the submillimetre sky is underway at the James Clerk Maxwell Telescope (JCMT) using SCUBA-2 and HARP, a heterodyne array receiver operating between 325 and 375 GHz. The JCMT Legacy Survey (JLS) is comprised of seven survey projects, and ranges in scope from the study of nearby debris disk systems, the study of star formation in nearby molecular cloud systems and more distant structures in our Galactic Plane, to the structure and composition of galaxies in our local neighbourhood and the number and evolution of submillimetre galaxies at high redshifts in the early Universe. In addition to the JLS, the COHR survey is imaging the Galactic plane in CO (3-2) and a JAC Staff-led project is using SCUBA-2 to survey the Galactic Centre. This poster highlights the significant survey capabilities of SCUBA-2 and HARP and reveals the continuing importance of the JCMT in a post-Herschel, ALMA world.

  10. Demonstration of a Data Distribution System for ALMA Data Cubes

    NASA Astrophysics Data System (ADS)

    Eguchi, S.; Kawasaki, W.; Shirasaki, Y.; Komiya, Y.; Kosugi, G.; Ohishi, M.; Mizumoto, Y.; Kobayashi, T.

    2014-05-01

    The Atacama Large Millimeter / submillimeter Array (ALMA) is the world's largest radio telescope in Chile. As a part of Japanese Virtual Observatory (JVO) system, we have been constructing a prototype of data service to distribute ALMA data, which are three or four dimensional cubes and expected to exceed 2 TB in total size, corresponding to 75 days at world-averaged Internet bandwidth of 2.6 Mbps, in the next three years. To utilize the limited bandwidth, our system adopts a higher dimensional version of so-called "deep zoom": the system generates and stores lower resolution FITS data cubes with various binning parameters in directions of both space and frequency. Users of our portal site can easily visualize and cut out those data cubes by using ALMAWebQL, which is a web application built on customized GWT. Once the FITS files are downloaded via ALMAWebQL, one can visualize them in more detail using Vissage, a Java-based FITS cube browser. We exhibited our web and desktop viewer “fresh from the oven” at the last ADASS conference (Shirasaki et al. 2013). Improvement of their performance and functionality after that made the system nearly to a practical level. The performance problem of ALMAWebQL reported last year (Eguchi et al. 2013) was overcome by optimizing the network topology and applying the just-in-time endian conversion algorithm; the latest ALMAWebQL can follow up any user actions almost in real time for files smaller than 5 GB. It also enables users to define either a sub-region or sub-frequency range and move it freely on the graphical user interface, providing more detailed information of the FITS file. In addition, the latest Vissage now supports data from other telescopes including HST, Subaru, Chandra, etc. and overlaying two images. In this paper, we introduce the latest version of our VO system.

  11. ACA phase calibration scheme with the ALMA water vapor radiometers

    NASA Astrophysics Data System (ADS)

    Asaki, Yoshiharu; Matsushita, Satoki; Morita, Koh-Ichiro; Nikolic, Bojan

    2012-09-01

    In Atacama Large Millimeter/submillimeter Array (ALMA) commissioning and science verification we have conducted a series of experiments of a novel phase calibration scheme for Atacama Compact Array (ACA). In this scheme water vapor radiometers (WVRs) devoted to measurements of tropospheric water vapor content are attached to ACA’s four total-power array (TP Array) antennas surrounding the 7 m dish interferometer array (7 m Array). The excess path length (EPL) due to the water vapor variations aloft is fitted to a simple two-dimensional slope using WVR measurements. Interferometric phase fluctuations for each baseline of the 7 m Array are obtained from differences of EPL inferred from the two-dimensional slope and subtracted from the interferometric phases. In the experiments we used nine ALMA 12-m antennas. Eight of them were closely located in a 70-m square region, forming a compact array like ACA. We supposed the most four outsiders to be the TP Array while the inner 4 antennas were supposed to be the 7 m Array, so that this phase correction scheme (planar-fit) was tested and compared with the WVR phase correction. We estimated residual root-mean-square (RMS) phases for 17- to 41-m baselines after the planar-fit phase correction, and found that this scheme reduces the RMS phase to a 70 - 90 % level. The planar-fit phase correction was proved to be promising for ACA, and how high or low PWV this scheme effectively works in ACA is an important item to be clarified.

  12. Observing the Sun with ALMA: A New Window into Solar Physics

    NASA Astrophysics Data System (ADS)

    Bastian, Timothy S.; Shimojo, Masumi; Wedemeyer-Bohm, Sven; ALMA North American Solar Development Team

    2015-01-01

    The Atacama Large Millimeter/Submillimeter Array (ALMA) is a joint North American, European, and East Asian interferometric array that opens the mm-submm wavelength part of the electromagnetic spectrum for general astrophysical exploration, providing high resolution imaging in frequency bands. Despite being a general purpose instrument, provisions have been made to enable solar observations with ALMA, thereby offering a new window into solar physics. Radiation emitted at ALMA wavelengths originates mostly from the chromosphere, which plays an important role in the transport of energy and matter and the heating of the outer layers of the solar atmosphere. Despite decades of intensive research, an understanding of the chromosphere is still elusive, and challenging to observe owing to the complicated formation mechanisms of currently available diagnostics. ALMA will change the scene substantially as it serves as a nearly linear thermometer at high spatial, temporal, and spectral resolution, enabling us to study the complex interaction of magnetic fields and shock waves and yet-to-be-discovered dynamical processes.Moreover, ALMA will play an important role in the study of energetic emissions associated with solar flares at sub-THz frequencies.This presentations introduces ALMA to the solar physcis community and motivates the science that can be addressed by ALMA using a number of examples based on 3D MHD simulations. In addition, the means by which ALMA is used to acquire and calibrate solar observations will be discussed. Finally, we encourage potential users to join us in further defining and articulating the exciting science to be explored with this fundamentally new instrument.

  13. Software Development for ALMA in Chile: The ACS-UTFSM Group.

    NASA Astrophysics Data System (ADS)

    von Brand, H. H.

    ALMA Common Software (ACS) provides a common software framework for ALMA, the Atacama Large Millimeter Array in Chile. ACS is a collection of well-documented patterns for controlling systems and a set of components written to those patterns. In its core, ACS is a distributed, object-oriented system, written on top of CORBA. The ACS-UTFSM Group started as some students of informatics did summer jobs at the La Silla Observatory of ESO, where they became acquainted with ACS. Their interest led them to continue working on ACS on their own, and they eventually became official developers of the package. Now the group is being funded by project ALMA-CONICYT 31060008 ``Software Development for ALMA: Building Up Expertise to Meet ALMA Software Requirements within a Chilean University''. Several members of the original group are now working for ALMA, which fullfills one of the goals of the project. Some parts of ACS developed by the ACS-UTFSM Group include H3E (Hardware End-to-End Example), a Lego model of a telescope and its controlling software for training and demonstration purposes; and CDBChecker, a tool to verify the consistency of the configuration database for a ACS deployment. Currently we are working towards a general framework for telescope control using ACS, in order to simplify the deployment of new instruments; and repackaging ACS so it is easier to install and use. A master's thesis is exploring the real-time requirements of ACS.

  14. Solar Observations with the Atacama Large Millimeter/submillimeter Array (ALMA)

    NASA Astrophysics Data System (ADS)

    Bastian, Timothy S.

    2015-04-01

    The Atacama Large Millimeter/Submillimeter Array (ALMA) is a joint North American, European, and East Asian project that opens the mm-submm wavelength part of the electromagnetic spectrum for general astrophysical exploration, providing high-resolution imaging in frequency bands currently ranging from 84 GHz to 950 GHz (300 microns to 3 mm). Despite being a general purpose instrument, provisions have been made to enable solar observations with ALMA. Radiation emitted at ALMA wavelengths originates mostly from the chromosphere, which plays an important role in the transport of matter and energy, and the in heating the outer layers of the solar atmosphere. Despite decades of research, the solar chromosphere remains a significant challenge: both to observe, owing to the complicated formation mechanisms of currently available diagnostics; and to understand, as a result of the complex nature of the structure and dynamics of the chromosphere. ALMA has the potential to change the scene substantially as it serves as a nearly linear thermometer at high spatial and temporal resolution, enabling us to study the complex interaction of magnetic fields and shock waves and yet-to-be-discovered dynamical processes. Moreover, ALMA will play an important role in the study of energetic emissions associated with solar flares at sub-THz frequencies.In this paper we describe recent efforts to ensure that ALMA can be usefully exploited by the scientific community to address outstanding questions in solar physics. We summarize activities by the ALMA solar development team comprised of scientists from the East Asia, North America, and Europe. These activities include instrument testing, development of calibration and imaging strategies, software requirements development, and science simulations. Opportunities for the wider community to contribute to these efforts will be highlighted.

  15. Molecular disks in radio galaxies. The pathway to ALMA

    NASA Astrophysics Data System (ADS)

    Prandoni, I.; Laing, R. A.; de Ruiter, H. R.; Parma, P.

    2010-11-01

    Context. It has recently been proposed that the jets of low-luminosity radio galaxies are powered by direct accretion of the hot phase of the IGM onto the central black hole. Cold gas remains a plausible alternative fuel supply, however. The most compelling evidence that cold gas plays a role in fueling radio galaxies is that dust is detected more commonly and/or in larger quantities in (elliptical) radio galaxies compared with radio-quiet elliptical galaxies. On the other hand, only small numbers of radio galaxies have yet been detected in CO (and even fewer imaged), and whether or not all radio galaxies have enough cold gas to fuel their jets remains an open question. If so, then the dynamics of the cold gas in the nuclei of radio galaxies may provide important clues to the fuelling mechanism. Aims: The only instrument capable of imaging the molecular component on scales relevant to the accretion process is ALMA, but very little is yet known about CO in southern radio galaxies. Our aim is to measure the CO content in a complete volume-limited sample of southern radio galaxies, in order to create a well-defined list of nearby targets to be imaged in the near future with ALMA. Methods: APEX [This publication is based on data acquired with the Atacama Pathfinder Experiment (APEX). APEX is a collaboration between the Max-Planck-Institut fur Radioastronomie, the European Southern Observatory, and the Onsala Space Observatory.] has recently been equipped with a receiver (APEX-1) able to observe the 230 GHz waveband. This allows us to search for CO(2-1) line emission in our target galaxies. Results: Here we present the results for our first three southern targets, proposed for APEX-1 spectroscopy during science verification: NGC 3557, IC 4296 and NGC 1399. The experiment was successful with two targets detected, and possible indications for a double-horned CO line profile, consistent with ordered rotation. These early results are encouraging, demonstrating that APEX can

  16. Detection of Atmospheric CO on Pluto with ALMA

    NASA Astrophysics Data System (ADS)

    Gurwell, Mark; Lellouch, Emmanuel; Butler, Bryan; Moullet, Arielle; Moreno, Raphael; Bockelée-Morvan, Dominique; Biver, Nicolas; Fouchet, Thierry; Lis, Darek; Stern, Alan; Young, Leslie; Young, Eliot; Weaver, Hal; Boissier, Jeremie; Stansberry, John

    2015-11-01

    We observed Pluto and Charon using the Atacama Large Millimeter/submillimeter Array (ALMA) interferometer in Northern Chile on June 12.2 and June 13.15, 2015, just one month prior to the New Horizons flyby of the system. The configuration of ALMA at the time provided ~0.3" resolution, allowing separation of emission from Pluto and Charon. This project targeted multiple science goals, including a search for HCN in Pluto's atmosphere [1] and high precision measurements of the individual brightness temperatures of Pluto and Charon [2], also presented at this meeting. Here we report the high SNR detection of carbon monoxide in the atmosphere of Pluto. The CO(3-2) rotational line, at 345.796 GHz (867 μm), was observed with 117 kHz spectral resolution for 45 min (on-source) on each date, providing ~3.5mJy/channel RMS. CO emission was clearly detected on both days, with a contrast of ~65 mJy above the Pluto continuum, and ~1.8 MHz FWHM linewidth, with the combined integrated line SNR >50. The presence of CO in Pluto's atmosphere is expected due to it's presence as ice on the surface in vapor pressure equilibrium with the atmosphere (e.g. [3],[4]), and it was previously detected at modest SNR in the near-IR using the VLT [5]. A preliminary assessment based upon the CO line wings shows the fractional abundance of CO is 500-750 ppm, consistent with that found in [5]. Further, the shape of the line core emission (assuming a constant CO mixing ratio), suggests that the atmospheric temperature rises quickly from the surface to ~100-110 K in the altitude range 20-70 km but decreases above that, falling to about 70 K by 200 km altitude. A detailed line inversion analysis will be performed and results presented.[1] Lellouch et al, this meeting. [2] Butler et al., this meeting. [3] Owen et al (1993), Science, 261, pp. 745-748. [4] Spencer et al (1993), In Pluto and Charon, pp. 435-473. Univ. of Arizona Press, Tucson. [5] Lellouch et al (2011), A&A, 530, L4.

  17. First North American Antenna Enables Next Phase in Joint ALMA Observatory

    NASA Astrophysics Data System (ADS)

    2009-02-01

    Astronomers celebrated today the formal acceptance of the first North American antenna by the Joint ALMA Observatory. ALMA, the Atacama Large Millimeter/submillimeter Array, is a gathering armada of short-wavelength radio telescopes whose combined power will enable astronomers to probe with unprecedented sharpness phenomena and regions that are beyond the reach of visible-light telescopes. The observatory is being assembled high in the Chilean Andes by a global partnership. The 12-meter-diameter antenna delivered today is the first of twenty-five being provided by North America’s ALMA partners, whose efforts are led by the National Radio Astronomy Observatory (NRAO) and supported by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada and the National Science Council of Taiwan. The antenna was manufactured by General Dynamics SATCOM Technologies. The acceptance comes just weeks after the first ALMA antenna, produced under the direction of the National Astronomical Observatory of Japan on behalf of ALMA’s East Asian partners, was handed over to the observatory. “These ALMA antennas are technological marvels,” said Thijs de Graauw, ALMA Director. “They are more precise and more capable than any ever made. Their performance in the harsh winds and temperatures of our high-altitude site bodes well for the observatory’s future.” A single 12-meter antenna’s dish is bigger than the largest optical telescope’s reflective mirror, but to match the sharpness achieved by an optical telescope, a millimeter-wavelength dish would have to be impossibly large, miles across. ALMA will combine signals from dozens of antennas spread across miles of desert to synthesize the effective sharpness of such a single, gigantic antenna. The process involves analysis of the ways in which the signals coming from each antenna interfere with one another, and is called interferometry. “This is a major milestone for the ALMA

  18. ALMA observations of the Red Rectangle, a preliminary analysis

    NASA Astrophysics Data System (ADS)

    Bujarrabal, V.; Castro-Carrizo, A.; Alcolea, J.; Van Winckel, H.; Sánchez Contreras, C.; Santander-García, M.; Neri, R.; Lucas, R.

    2013-09-01

    Aims: We aim to study equatorial disks in rotation and axial outflows in post-AGB objects so as to disclose the formation and shaping mechanisms in planetary nebulae. So far, both disks and outflows have not been observed simultaneously. Methods: We obtained high-quality ALMA observations of 12CO and 13CO J = 3-2 and 12CO J = 6-5 line emission in the Red Rectangle, the only post-AGB/protoplanetary object for which a disk in rotation has been mapped. Results: These observations provide an unprecedented description of the complex structure of this source. Together with an equatorial disk in rotation, we find a low-velocity outflow that more or less occupies the region situated between the disk and the optical X-shaped nebula. From our observations and preliminary modeling of the data, we confirm the previously known properties of the disk and obtain a first description of the structure, dynamics, and physical conditions of the outflow. Appendix A is available in electronic form at http://www.aanda.org

  19. New architectures support for ALMA common software: lessons learned

    NASA Astrophysics Data System (ADS)

    Menay, Camilo E.; Zamora, Gabriel A.; Tobar, Rodrigo J.; Avarias, Jorge A.; Dahl-skog, Kevin R.; von Brand, Horst H.; Chiozzi, Gianluca

    2010-07-01

    ALMA Common Software (ACS) is a distributed control framework based on CORBA that provides communication between distributed pieces of software. Because of its size and complexity it provides its own compilation system, a mix of several technologies. The current ACS compilation process depends on specific tools, compilers, code generation, and a strict dependency model induced by the large number of software components. This document presents a summary of several porting and compatibility attempts at using ACS on platforms other than the officially supported one. A porting of ACS to the Microsoft Windows Platform and to the ARM processor architecture were attempted, with different grades of success. Also, support for LINUX-PREEMPT (a set of real-time patches for the Linux kernel) using a new design for real-time services was implemented. These efforts were integrated with the ACS building and compilation system, while others were included in its design. Lessons learned in this process are presented, and a general approach is extracted from them.

  20. ALMA Observations of the IR-Bright Merger VV114

    NASA Astrophysics Data System (ADS)

    Saito, T.; Iono, D.; Yun, M.; Ueda, J.; Espada, D.; Hagiwara, Y.; Imanishi, M.; Motohara, K.; Nakanishi, K.; Sugai, H.; Tateuchi, K.; Kawabe, R.

    2013-10-01

    The importance of galaxy mergers in the context of galaxy formation and evolution have been clearly demonstrated in various numerical simulations. The violent merger event not only results in large scale morphological transformation and mass accumulation, but it also triggers gas compression, turbulence, and gas inflow to the galactic center region. We present high resolution 12CO(1-0), 13CO(1-0), HCN(4-3), HCO+(4-3), CN(13/2-01/2), CN(11/2-01/2), CS(2-1), CH3OH(2-1), and CS(7-6) maps of an IR-bright late stage merger VV114 obtained during cycle 0 of ALMA. An unresolved strong HCN(4-3) source is detected at the nucleus of VV114E and has a high velocity dispersion (≃ 300 km s-1), and these features are also shown in HCO+(4-3). These evidences suggest that this source has an obscured AGN. We also find a clumpy filament with resolved dense gas across the galaxy disks. This filament has clumpy star-forming regions at each regions. Each region of this filament clearly shows the physical and chemical differences in our molecular line results.

  1. ALMA observations of TiO2 around VY CMa

    NASA Astrophysics Data System (ADS)

    De Beck, Elvire; Vlemmings, Wouter; Muller, Sébastien; Black, John H.; O'Gorman, Eamon; Richards, Anita M. S.; Baudry, Alain; Maercker, Matthias; Decin, Leen; Humphreys, Elizabeth M.

    2016-07-01

    Titanium dioxide, TiO2, is a refractory species that could play a crucial role in the dust-condensation sequence around oxygen-rich evolved stars. We present and discuss the detections of 15 emission lines of TiO2 with ALMA in the complex environment of the red supergiant VY CMa. The observations reveal a highly clumpy, anisotropic outflow in which the TiO2 emission likely traces gas exposed to the stellar radiation field. We find evidence for a roughly east-west oriented, accelerating bipolar-like structure, of which the blue component runs into and breaks up around a solid continuum component. We see a distinct tail to the south-west for some transitions, consistent with features seen in the optical and near-infrared. We find that a significant fraction of TiO2 remains in the gas phase outside the dust-formation zone and suggest that this species might play only a minor role in the dust-condensation process around extreme oxygen-rich evolved stars like VY CMa.

  2. Design of Balanced Mixers for ALMA Band-10

    NASA Astrophysics Data System (ADS)

    Shitov, Sergey V.; Koryukin, Oleg V.; Uzawa, Yoshinori; Noguchi, Takashi; Uvarov, Andrey V.; Bukovski, Maksim A.; Cohn, Ilya A.

    2007-06-01

    Two variants of balanced mixer employing twin-SIS structure are under development for 787-950 GHz frequency range. Easy-to-use Geometry Transformation method for modeling of superconducting microstrips is developed, compared to referenced methods and used for design of the mixers. Lens-antenna mixer is based on cross-slot antenna; it does not need any intervening optics between its lens and sub-reflector of ALMA telescope; simple yet efficient composition of lens-antenna cartridge is suggested. Compact single-chamber balanced waveguide mixer employs two SIS chips and capacitive probe for LO injection; coupling above -3 dB and signal loss below -20 dB are expected. Need in shifting of resonance frequency of twin-SIS mixer towards top of the frequency band is predicted using Tucker's theory in large-signal approximation. TRX considerably below 200 K (DSB) is simulated using high-quality hybrid SIS junction for NbTiN/Nb - AlOx - Nb/Al for Jc = 12 kA/cm2.

  3. Exploring No-SQL alternatives for ALMA monitoring system

    NASA Astrophysics Data System (ADS)

    Shen, Tzu-Chiang; Soto, Ruben; Merino, Patricio; Peña, Leonel; Bartsch, Marcelo; Aguirre, Alvaro; Ibsen, Jorge

    2014-07-01

    The Atacama Large Millimeter /submillimeter Array (ALMA) will be a unique research instrument composed of at least 66 reconfigurable high-precision antennas, located at the Chajnantor plain in the Chilean Andes at an elevation of 5000 m. This paper describes the experience gained after several years working with the monitoring system, which has a strong requirement of collecting and storing up to 150K variables with a highest sampling rate of 20.8 kHz. The original design was built on top of a cluster of relational database server and network attached storage with fiber channel interface. As the number of monitoring points increases with the number of antennas included in the array, the current monitoring system demonstrated to be able to handle the increased data rate in the collection and storage area (only one month of data), but the data query interface showed serious performance degradation. A solution based on no-SQL platform was explored as an alternative to the current long-term storage system. Among several alternatives, mongoDB has been selected. In the data flow, intermediate cache servers based on Redis were introduced to allow faster streaming of the most recently acquired data to web based charts and applications for online data analysis.

  4. ALMA - The March to Early Science and Beyond

    NASA Astrophysics Data System (ADS)

    Wootten, Alwyn

    2011-01-01

    The Atacama Large Millimeter/submillimeter Array is rapidly proceeding through its commissioning stages in Chile. Tests at the atmospherically superb 5050m Array Operations Site and readiness reviews held during the Fall of 2010 will result in a decision to issue a call for proposals to use the instrument during its 'Early Science' phase. At the beginning of Early Science, projected for later in 2011, 16 antennas of the final 66 will stand ready to produce the deepest integrations ever achieved in the cool thermal spectral region. The array will be equipped with at least three of its eventual complement of ten receivers operating over a decade of bandwidth from 3.6mm to 0.42mm. At this point, its sensitivity will be on the order of 0.5mJy in a minute's integration. Operating at this stage baselines of at least .25km, ALMA will provide a beam as small as 0".3 on the little-explored southern skies from its Chilean site near the Tropic of Capricorn. By one year later, the array will have grown to more than fifty antennas; at the second call for proposals the array will reach 0.2 mJy in a minute and baselines will extend to the full set of array configurations, effectively about 14 km. Observations which will be made possible by these transformative capabilities will be presented.

  5. ALMA: The March to Early Science and Beyond

    NASA Astrophysics Data System (ADS)

    Wootten, Al

    2010-05-01

    The Atacama Large Millimeter/submillimeter Array is rapidly proceeding through its commissioning stages in Chile. Within a short time, equipment from all over the world will be installed at the 5050m altitude Array Operations Site and a call will go out for proposals to use the instrument during its 'Early Science' phase. At the beginning of Early Science, a little over a year from now, 16 antennas of the final 66 will stand ready to produce the deepest images ever achieved in the cool thermal spectral region. The array will be equipped with at least three of its eventual complement of ten receivers; even now operating over a decade of bandwidth from 3.6mm to 0.42mm. At this point, its sensitivity will be on the order of 0.5mJy in a minute's integration. Operating at this stage baselines of at least .25km, ALMA will provide a beam as small as 0".3 on the little-explored southern skies from its Chilean site near the Tropic of Capricorn. By one year later, the array will have grown to more than fifty antennas; at the second call for proposals the array will reach 0.2 mJy in a minute and baselines will extend to the full set of array configurations, effectively about 14 km. Illustrative examples of observations which will be made possible by these transformative capabilities will be presented.

  6. ALMA OBSERVATIONS OF THE HH 46/47 MOLECULAR OUTFLOW

    SciTech Connect

    Arce, Hector G.; Mardones, Diego; Garay, Guido; Corder, Stuartt A.; Noriega-Crespo, Alberto; Raga, Alejandro C.

    2013-09-01

    The morphology, kinematics, and entrainment mechanism of the HH 46/47 molecular outflow were studied using new ALMA Cycle 0 observations. Results show that the blue and red lobes are strikingly different. We argue that these differences are partly due to contrasting ambient densities that result in different wind components having a distinct effect on the entrained gas in each lobe. A 29 point mosaic, covering the two lobes at an angular resolution of about 3'', detected outflow emission at much higher velocities than previous observations, resulting in significantly higher estimates of the outflow momentum and kinetic energy than previous studies of this source, using the CO(1-0) line. The morphology and the kinematics of the gas in the blue lobe are consistent with models of outflow entrainment by a wide-angle wind, and a simple model describes the observed structures in the position-velocity diagram and the velocity-integrated intensity maps. The red lobe exhibits a more complex structure, and there is evidence that this lobe is entrained by a wide-angle wind and a collimated episodic wind. Three major clumps along the outflow axis show velocity distribution consistent with prompt entrainment by different bow shocks formed by periodic mass ejection episodes which take place every few hundred years. Position-velocity cuts perpendicular to the outflow cavity show gradients where the velocity increases toward the outflow axis, inconsistent with outflow rotation. Additionally, we find evidence for the existence of a small outflow driven by a binary companion.

  7. ALMA and SINFONI high redshift observations to test AGN feedback

    NASA Astrophysics Data System (ADS)

    Kakkad, D.; Mainieri, V.; Padovani, P.; Cresci, G.; Husemann, B.; Carniani, S.; Brusa, M.; Lamastra, A.; Lanzuisi, G.; Feruglio, C.; Piconcelli, E.; Schramm, M.

    2016-08-01

    The epoch between redshift of 1-3 has become the prime focus of many galaxy evolutionary studies as the accretion rates of super massive black holes at the galactic center and the star formation rates of their hosts peaked around this period, pointing to their co-evolution throughout cosmic history. We will present two different approaches to study the impact of high redshift AGN (z~1.5) on the host galaxy: a) CO(2-1) observations from ALMA in a sample of "main sequence" AGNs to compare the star formation efficiency and gas fractions in active and inactive galaxies. b) SINFONI-IFU observations of a representative sample of high redshift quasars for which we observe intermediate to high velocity outflows using [OIII]5007 line diagnostics. These outflows are extended up-to kiloparsec scales and have an asymmetric geometry. With these approaches, one is able to test the effect of AGN feedback on the molecular as well as the ionized gas content.

  8. A code generation framework for the ALMA common software

    NASA Astrophysics Data System (ADS)

    Troncoso, Nicolás; von Brand, Horst H.; Ibsen, Jorge; Mora, Matias; Gonzalez, Victor; Chiozzi, Gianluca; Jeram, Bogdan; Sommer, Heiko; Zamora, Gabriel; Tejeda, Alexis

    2010-07-01

    Code generation helps in smoothing the learning curve of a complex application framework and in reducing the number of Lines Of Code (LOC) that a developer needs to craft. The ALMA Common Software (ACS) has adopted code generation in specific areas, but we are now exploiting the more comprehensive approach of Model Driven code generation to transform directly an UML Model into a full implementation in the ACS framework. This approach makes it easier for newcomers to grasp the principles of the framework. Moreover, a lower handcrafted LOC reduces the error rate. Additional benefits achieved by model driven code generation are: software reuse, implicit application of design patterns and automatic tests generation. A model driven approach to design makes it also possible using the same model with different frameworks, by generating for different targets. The generation framework presented in this paper uses openArchitectureWare1 as the model to text translator. OpenArchitectureWare provides a powerful functional language that makes this easier to implement the correct mapping of data types, the main difficulty encountered in the translation process. The output is an ACS application readily usable by the developer, including the necessary deployment configuration, thus minimizing any configuration burden during testing. The specific application code is implemented by extending generated classes. Therefore, generated and manually crafted code are kept apart, simplifying the code generation process and aiding the developers by keeping a clean logical separation between the two. Our first results show that code generation improves dramatically the code productivity.

  9. ALMA Observations of HCN and Its Isotopologues on Titan

    NASA Astrophysics Data System (ADS)

    Molter, Edward M.; Nixon, C. A.; Cordiner, M. A.; Serigano, J.; Irwin, P. G. J.; Teanby, N. A.; Charnley, S. B.; Lindberg, J. E.

    2016-08-01

    We present sub-millimeter spectra of HCN isotopologues on Titan, derived from publicly available ALMA flux calibration observations of Titan taken in early 2014. We report the detection of a new HCN isotopologue on Titan, H13C15N, and confirm an earlier report of detection of DCN. We model high signal-to-noise observations of HCN, H13CN, HC15N, DCN, and H13C15N to derive abundances and infer the following isotopic ratios: 12C/13C = 89.8 ± 2.8, 14N/15N = 72.3 ± 2.2, D/H = (2.5 ± 0.2) × 10-4, and HCN/H13C15N = 5800 ± 270 (1σ errors). The carbon and nitrogen ratios are consistent with and improve on the precision of previous results, confirming a factor of ˜2.3 elevation in 14N/15N in HCN compared to N2 and a lack of fractionation in 12C/13C from the protosolar value. This is the first published measurement of D/H in a nitrile species on Titan, and we find evidence for a factor of ˜2 deuterium enrichment in hydrogen cyanide compared to methane. The isotopic ratios we derive may be used as constraints for future models to better understand the fractionation processes occurring in Titan’s atmosphere.

  10. Resolving the planetesimal belt of HR 8799 with ALMA

    NASA Astrophysics Data System (ADS)

    Booth, Mark; Jordán, Andrés; Casassus, Simon; Hales, Antonio S.; Dent, William R. F.; Faramaz, Virginie; Matrà, Luca; Barkats, Denis; Brahm, Rafael; Cuadra, Jorge

    2016-07-01

    The star HR 8799 hosts one of the largest known debris discs and at least four giant planets. Previous observations have found evidence for a warm belt within the orbits of the planets, a cold planetesimal belt beyond their orbits and a halo of small grains. With the infrared data, it is hard to distinguish the planetesimal belt emission from that of the grains in the halo. With this in mind, the system has been observed with ALMA in band 6 (1.34 mm) using a compact array format. These observations allow the inner edge of the planetesimal belt to be resolved for the first time. A radial distribution of dust grains is fitted to the data using an MCMC method. The disc is best fitted by a broad ring between 145^{+12}_{-12} au and 429^{+37}_{-32} au at an inclination of 40^{+5}_{-6}° and a position angle of 51^{+8}_{-8}°. A disc edge at ˜145 au is too far out to be explained simply by interactions with planet b, requiring either a more complicated dynamical history or an extra planet beyond the orbit of planet b.

  11. Fast Single-Dish Scans of the Sun Using ALMA

    NASA Astrophysics Data System (ADS)

    Phillips, N.; Hills, R.; Bastian, T.; Hudson, H.; Marson, R.; Wedemeyer, S.

    2015-12-01

    We have implemented control and data-taking software that makes it possible to scan the beams of individual ALMA antennas to perform quite complex patterns while recording the signals at high rates. We conducted test observations of the Sun in September and December, 2014. The data returned have excellent quality; in particular they allow us to characterize the noise and signal fluctuations present in this kind of observation. The fast-scan experiments included both Lissajous patterns covering rectangular areas, and “double-circle” patterns of the whole disk of the Sun and smaller repeated maps of specific disk-shaped targets. With the latter we find that we can achieve roughly Nyquist sampling of the Band 6 (230 GHz) beam in 60 s over a region 300” in diameter. These maps show a peak-to-peak brightness-temperature range of up to 1000 K, while the time-series variability at any given point appears to be of order 0.5% RMS over times of a few minutes. We thus expect to be able to separate the noise contributions due to transparency fluctuations from variations in the Sun itself. Such timeseries have many advantages, in spite of the non-interferometric observations. In particular such data should make it possible to observe microflares in active regions and nanoflares in any part of the solar disk and low corona.

  12. ALMA Observations of HCN and Its Isotopologues on Titan

    NASA Astrophysics Data System (ADS)

    Molter, Edward M.; Nixon, C. A.; Cordiner, M. A.; Serigano, J.; Irwin, P. G. J.; Teanby, N. A.; Charnley, S. B.; Lindberg, J. E.

    2016-08-01

    We present sub-millimeter spectra of HCN isotopologues on Titan, derived from publicly available ALMA flux calibration observations of Titan taken in early 2014. We report the detection of a new HCN isotopologue on Titan, H13C15N, and confirm an earlier report of detection of DCN. We model high signal-to-noise observations of HCN, H13CN, HC15N, DCN, and H13C15N to derive abundances and infer the following isotopic ratios: 12C/13C = 89.8 ± 2.8, 14N/15N = 72.3 ± 2.2, D/H = (2.5 ± 0.2) × 10‑4, and HCN/H13C15N = 5800 ± 270 (1σ errors). The carbon and nitrogen ratios are consistent with and improve on the precision of previous results, confirming a factor of ˜2.3 elevation in 14N/15N in HCN compared to N2 and a lack of fractionation in 12C/13C from the protosolar value. This is the first published measurement of D/H in a nitrile species on Titan, and we find evidence for a factor of ˜2 deuterium enrichment in hydrogen cyanide compared to methane. The isotopic ratios we derive may be used as constraints for future models to better understand the fractionation processes occurring in Titan’s atmosphere.

  13. The Database for Astronomical Spectroscopy - Updates, Additions and Plans for Splatalogue for Alma Full Science Operations

    NASA Astrophysics Data System (ADS)

    Remijan, Anthony; Seifert, Nathan A.; McGuire, Brett A.

    2016-06-01

    For the past 10 years, Splatalogue has been constantly updated, modified and enhanced in order to make molecular spectroscopy data readily available to the astronomical community. Splatalogue is fully integrated into the ALMA Observing Tool, the ALMA data reduction and analysis package (CASA) and several enhanced tools being developed through the ALMA development program including the next generation CASA viewer (CARTA) and the ALMA Data Mining Toolkit (ADMIT). In anticipation for ALMA full science operations, a number of improvements have taken place over the past year to the Splatalogue database including, but not limited too, additions to Splatalogue from the JPL and CDMS line lists, improvements and reconciliation of the Lovas/NIST Catalog assigning NRAO recommended rest frequencies to every astronomically detected transition, including recent astronomical surveys to the list of transitions detected in space and finally, improved search and display features as requested by the astronomical community. Splatalogue is planning for the next 10 years of development and welcomes any and all contributions to improving the data integrity and availability to the scientific community.

  14. Solar Observations with the Atacama Large Millimeter/submillimeter Array (ALMA)

    NASA Astrophysics Data System (ADS)

    Kobelski, A.; ALMA Solar Development Team

    2016-04-01

    The Atacama Large Millimeter/Submillimeter Array (ALMA) is a joint North American, European, and East Asian project that opens the mm-sub mm wavelength part of the electromagnetic spectrum for general astrophysical exploration, providing high-resolution imaging in frequency bands currently ranging from 84 GHz to 950 GHz (300 microns to 3 mm). It is located in the Atacama desert in northern Chile at an elevation of 5000 m. Despite being a general purpose instrument, provisions have been made to enable solar observations with ALMA. Radiation emitted at ALMA wavelengths originates mostly from the chromosphere, which plays an important role in the transport of matter and energy, and the in heating the outer layers of the solar atmosphere. Despite decades of research, the solar chromosphere remains a significant challenge: both to observe, owing to the complicated formation mechanisms of currently available diagnostics; and to understand, as a result of the complex nature of the structure and dynamics of the chromosphere. ALMA has the potential to change the scene substantially as it serves as a nearly linear thermometer at high spatial and temporal resolution, enabling us to study the complex interaction of magnetic fields and shock waves and yet-to-be-discovered dynamical processes. Moreover, ALMA will play an important role in the study of energetic emissions associated with solar flares at sub-THz frequencies.

  15. The Cultural Implications of Primary Health Care and the Declaration of Alma-Ata: The Health District of Kedougou, Senegal

    ERIC Educational Resources Information Center

    Blanas, Demetri A.

    2008-01-01

    In 1978, the World Health Organization (WHO) and the international health community convoked a conference in Alma-Ata, Kazakhstan, to address global inequalities in health. The conference resulted in the publication of the "Declaration of Alma-Ata," which made the ambitious call "for urgent action by all governments, all health and development…

  16. ALMA service data analysis and level 2 quality assurance with CASA

    NASA Astrophysics Data System (ADS)

    Petry, Dirk; Vila-Vilaro, Baltasar; Villard, Eric; Komugi, Shinya; Schnee, Scott

    2014-07-01

    The Atacama Large mm and sub-mm Array (ALMA) radio observatory is one of the world's largest astronomical projects. After the very successful conclusion of the first observation cycles Early Science Cycles 0 and 1, the ALMA project can report many successes and lessons learned. The science data taken interleaved with commis- sioning tests for the still continuing addition of new capabilities has already resulted in numerous publications in high-profile journals. The increasing data volume and complexity are challenging but under control. The radio-astronomical data analysis package "Common Astronomy Software Applications" (CASA) has played a crucial role in this effort. This article describes the implementation of the ALMA data quality assurance system, in particular the level 2 which is based on CASA, and the lessons learned.

  17. Photonic Local Oscillator Test System for Atacama Large Millimeter/submillimeter Array (ALMA) - Summer Student Project

    NASA Astrophysics Data System (ADS)

    Gross, Cathleen; Christophe Jacques, Jason Castro, Bill Shillue

    2015-01-01

    The Atacama Large Millimeter Array (ALMA) consists of 66 high-precision antennas in Chile and draws great worldwide interest from astronomers and engineers. The objective of my summer research was to construct a subset of the installed Photonic Local Oscillator (LO) test station at the National Radio Astronomy Observatory (NRAO) in Charlottesville, VA. Installation of a full test system expedites the preparation of a fifth Laser Synthesizer (LS) for integration in the ALMA system. By utilizing the capabilities and partnership of fiber optics and electronics, the Charlottesville, Central LO Test System (cvCLOTS) was completed to test the LS, troubleshoot future malfunctioning parts, and creates an opportunity for other future ALMA upgrades.

  18. The European ALMA Regional Centre Network: A Geographically Distributed User Support Model

    NASA Astrophysics Data System (ADS)

    Hatziminaoglou, E.; Zwaan, M.; Andreani, P.; Barta, M.; Bertoldi, F.; Brand, J.; Gueth, F.; Hogerheijde, M.; Maercker, M.; Massardi, M.; Muehle, S.; Muxlow, Th.; Richards, A.; Schilke, P.; Tilanus, R.; Vlemmings, W.; Afonso, J.; Messias, H.

    2015-12-01

    In recent years there has been a paradigm shift from centralised to geographically distributed resources. Individual entities are no longer able to host or afford the necessary expertise in-house, and, as a consequence, society increasingly relies on widespread collaborations. Although such collaborations are now the norm for scientific projects, more technical structures providing support to a distributed scientific community without direct financial or other material benefits are scarce. The network of European ALMA Regional Centre (ARC) nodes is an example of such an internationally distributed user support network. It is an organised effort to provide the European ALMA user community with uniform expert support to enable optimal usage and scientific output of the ALMA facility. The network model for the European ARC nodes is described in terms of its organisation, communication strategies and user support.

  19. The ALMA Common Software as a Basis for a Distributed Software Development

    NASA Astrophysics Data System (ADS)

    Raffi, Gianni; Chiozzi, Gianluca; Glendenning, Brian

    The Atacama Large Millimeter Array (ALMA) is a joint project involving astronomical organizations in Europe, North America and Japan. ALMA will consist of 64 12-m antennas operating in the millimetre and sub-millimetre wavelength range, with baselines of more than 10 km. It will be located at an altitude above 5000 m in the Chilean Atacama desert. The ALMA Computing group is a joint group with staff scattered on 3 continents and is responsible for all the control and data flow software related to ALMA, including tools ranging from support of proposal preparation to archive access of automatically created images. Early in the project it was decided that an ALMA Common Software (ACS) would be developed as a way to provide to all partners involved in the development a common software platform. The original assumption was that some key middleware like communication via CORBA and the use of XML and Java would be part of the project. It was intended from the beginning to develop this software in an incremental way based on releases, so that it would then evolve into an essential embedded part of all ALMA software applications. In this way we would build a basic unity and coherence into a system that will have been developed in a distributed fashion. This paper evaluates our progress after 1.5 year of work, following a few tests and preliminary releases. It analyzes the advantages and difficulties of such an ambitious approach, which creates an interface across all the various control and data flow applications.

  20. SERENDIPITOUS ALMA DETECTION OF A DISTANT CO-EMITTING X-RAY BRIGHT GALAXY

    SciTech Connect

    Tamura, Yoichi; Saito, Toshiki; Iono, Daisuke; Kawabe, Ryohei; Tsuru, Takeshi G.; Uchida, Hiroyuki; Yun, Min S.; Espada, Daniel

    2014-02-01

    We report the detection of a distant star-forming galaxy, ALMA J010748.3–173028, which is identified by a 13σ emission line at 99.75 GHz (SΔv = 3.1 Jy km s{sup –1}), behind the nearby merging galaxies VV114 using the Atacama Large Millimeter/submillimeter Array (ALMA) Band 3. We also find an 880 μm counterpart with ALMA Band 7 (S {sub 880μm} = 11.2 mJy). A careful comparison of the intensities of the line and the continuum suggests that the line is a redshifted {sup 12}CO transition. A photometric redshift analysis using the infrared to radio data favors a CO redshift of z = 2.467, although z = 3.622 is acceptable. We also find a hard X-ray counterpart, suggesting the presence of a luminous (L {sub X} ∼ 10{sup 44} erg s{sup –1}) active galactic nucleus obscured by a large hydrogen column (N {sub H} ∼ 2 × 10{sup 23} cm{sup –2} if z = 2.47). A cosmological simulation shows that the chance detection rate of a CO-emitting galaxy at z > 1 with ≥1 Jy km s{sup –1} is ∼10{sup –3} per single ALMA field of view and 7.5 GHz bandwidth at 99.75 GHz. This demonstrates that ALMA has sufficient sensitivity to find an emission-line galaxy such as ALMA J010748.3–173028 even by chance, although the likelihood of stumbling across such a source is not high.

  1. Submillimeter mapping of mesospheric minor species on Venus with ALMA

    NASA Astrophysics Data System (ADS)

    Encrenaz, T.; Moreno, R.; Moullet, A.; Lellouch, E.; Fouchet, T.

    2015-08-01

    Millimeter and submillimeter heterodyne spectroscopy offers the possibility of probing the mesosphere of Venus and monitoring minor species and winds. ALMA presents a unique opportunity to map mesospheric species of Venus. During Cycle 0, we have observed Venus on November 14 and 15, 2011, using the compact configuration of ALMA. The diameter of Venus was 11″ and the illumination factor was about 90%. Maps of CO, SO, SO2 and HDO have been built from transitions recorded in the 335-347 GHz frequency range. A mean mesospheric thermal profile has been inferred from the analysis of the CO transition at the disk center, to be used in support of minor species retrieval. Maps of SO and SO2 abundance show significant local variations over the disk and contrast variations by as much as a factor 4. In the case of SO2, the spatial distribution appears more "patchy", i.e. shows short-scale structures apparently disconnected from day-side and latitudinal variations. For both molecules, significant changes occur over a timescale of one day. From the disk averaged spectrum of SO recorded on November 14 at 346.528 GHz, we find that the best fit is obtained with a cutoff in the SO vertical distribution at 88±2 km and a uniform mixing ratio of 8.0±2.0 ppb above this level. The SO2 map of November 14, derived from the weaker transition at 346.652 GHz, shows a clear maximum in the morning side at low latitudes, which is less visible in the map of November 15. We find that the best fit for SO2 is obtained for a cutoff in the vertical distribution at 88±3 km and a uniform mixing ratio of 12.0±3.5 ppb above this level. The HDO maps retrieved from the 335.395 GHz show some enhancement in the northern hemisphere, but less contrasted variations than for the sulfur species maps, with little change between November 14 and 15. Assuming a typical D/H ratio of 200 times the terrestrial value in the mesosphere of Venus, we find that the disk averaged HDO spectrum is best fitted with a

  2. ETHYL CYANIDE ON TITAN: SPECTROSCOPIC DETECTION AND MAPPING USING ALMA

    SciTech Connect

    Cordiner, M. A.; Palmer, M. Y.; Nixon, C. A.; Charnley, S. B.; Mumma, M. J.; Serigano, J.; Irwin, P. G. J.; Teanby, N. A.; Kisiel, Z.; Wang, K.-S.

    2015-02-10

    We report the first spectroscopic detection of ethyl cyanide (C{sub 2}H{sub 5}CN) in Titan’s atmosphere, obtained using spectrally and spatially resolved observations of multiple emission lines with the Atacama Large Millimeter/submillimeter Array (ALMA). The presence of C{sub 2}H{sub 5}CN in Titan’s ionosphere was previously inferred from Cassini ion mass spectrometry measurements of C{sub 2}H{sub 5}CNH{sup +}. Here we report the detection of 27 rotational lines from C{sub 2}H{sub 5}CN (in 19 separate emission features detected at >3σ confidence) in the frequency range 222–241 GHz. Simultaneous detections of multiple emission lines from HC{sub 3}N, CH{sub 3}CN, and CH{sub 3}CCH were also obtained. In contrast to HC{sub 3}N, CH{sub 3}CN, and CH{sub 3}CCH, which peak in Titan’s northern (spring) hemisphere, the emission from C{sub 2}H{sub 5}CN is found to be concentrated in the southern (autumn) hemisphere, suggesting a distinctly different chemistry for this species, consistent with a relatively short chemical lifetime for C{sub 2}H{sub 5}CN. Radiative transfer models show that C{sub 2}H{sub 5}CN is most concentrated at altitudes ≳200 km, suggesting production predominantly in the stratosphere and above. Vertical column densities are found to be in the range (1–5) × 10{sup 14} cm{sup −2}.

  3. The Early ALMA View of the FU Ori Outburst System

    NASA Astrophysics Data System (ADS)

    Hales, A. S.; Corder, S. A.; Dent, W. R. D.; Andrews, S. M.; Eisner, J. A.; Cieza, L. A.

    2015-10-01

    We have obtained ALMA Band 7 observations of the FU Ori outburst system at a 0.″6 × 0.″5 resolution to measure the link between the inner disk instability and the outer disk through submillimeter continuum and molecular line observations. Our observations detect continuum emission that can be well-modeled by two unresolved sources located at the position of each binary component. The interferometric observations recover the entire flux reported in previous single-dish studies, ruling out the presence of a large envelope. Assuming that the dust is optically thin, we derive disk dust masses of 2 × 10‑4 M⊙ and 8× {10}-5 M⊙ for the north and south components, respectively. We place limits on the disks’ radii of r < 45 AU. We report the detection of molecular emission from 12CO(3-2), HCO+(4-3), and from HCN(4-3). The 12CO appears widespread across the two binary components and is slightly more extended than the continuum emission. The denser gas tracer HCO+ peaks close to the position of the southern binary component, while HCN appears to be peaked at the position of the northern component. This suggests that the southern binary component is embedded in denser molecular material, consistent with previous studies that indicate a heavily reddened object. At this angular resolution, any interaction between the two unresolved disk components cannot be disentangled. Higher-resolution images are vital for understanding the process of star formation via rapid accretion FU Ori-type episodes.

  4. The Early ALMA View of the FU Ori Outburst System

    NASA Astrophysics Data System (ADS)

    Hales, A. S.; Corder, S. A.; Dent, W. R. D.; Andrews, S. M.; Eisner, J. A.; Cieza, L. A.

    2015-10-01

    We have obtained ALMA Band 7 observations of the FU Ori outburst system at a 0.″6 × 0.″5 resolution to measure the link between the inner disk instability and the outer disk through submillimeter continuum and molecular line observations. Our observations detect continuum emission that can be well-modeled by two unresolved sources located at the position of each binary component. The interferometric observations recover the entire flux reported in previous single-dish studies, ruling out the presence of a large envelope. Assuming that the dust is optically thin, we derive disk dust masses of 2 × 10-4 M⊙ and 8× {10}-5 M⊙ for the north and south components, respectively. We place limits on the disks’ radii of r < 45 AU. We report the detection of molecular emission from 12CO(3-2), HCO+(4-3), and from HCN(4-3). The 12CO appears widespread across the two binary components and is slightly more extended than the continuum emission. The denser gas tracer HCO+ peaks close to the position of the southern binary component, while HCN appears to be peaked at the position of the northern component. This suggests that the southern binary component is embedded in denser molecular material, consistent with previous studies that indicate a heavily reddened object. At this angular resolution, any interaction between the two unresolved disk components cannot be disentangled. Higher-resolution images are vital for understanding the process of star formation via rapid accretion FU Ori-type episodes.

  5. A web-based dashboard for the high-level monitoring of ALMA

    NASA Astrophysics Data System (ADS)

    Pietriga, Emmanuel; Filippi, Giorgio; Véliz, Luis; del Campo, Fernando; Ibsen, Jorge

    2014-07-01

    The ALMA radio-telescope's operations depend on the availability of high-level, easy-to-understand status information about all of its components. The ALMA Dashboard aims at providing an all-in-one-place near-real-time overview of the observatory's key elements and figures to both line and senior management. The Dashboard covers a wide range of elements beyond antennas, such as pads, correlator and central local oscillator. Data can be displayed in multiple ways, including: a table view, a compact view fitting on a single screen, a timeline showing detailed information over time, a logbook, a geographical map.

  6. Primary health care in the Eastern Mediterranean Region: from Alma-Ata to Doha.

    PubMed

    Shawky, S

    2010-12-01

    The celebration in Doha of the 30th anniversary of the Alma-Ata Declaration at the International Conference on Primary Health Care renewed the commitment of the Eastern Mediterranean Region to primary health care as the tool for better health. The principles agreed at Alma-Ata in 1978 apply as much now as they did before. The event provided an opportunity for the Eastern Mediterranean countries to define future directions to steer the health systems to integrate primary health care and harness the intersectoral approach.

  7. Measuring turbulence in TW Hydrae with ALMA: methods and limitations

    NASA Astrophysics Data System (ADS)

    Teague, R.; Guilloteau, S.; Semenov, D.; Henning, Th.; Dutrey, A.; Piétu, V.; Birnstiel, T.; Chapillon, E.; Hollenbach, D.; Gorti, U.

    2016-07-01

    Aims: We aim to obtain a spatially resolved measurement of velocity dispersions in the disk of TW Hya. Methods: We obtained images with high spatial and spectral resolution of the CO J = 2-1, CN N = 2-1 and CS J = 5-4 emission with ALMA in Cycle 2. The radial distribution of the turbulent broadening was derived with two direct methods and one modelling approach. The first method requires a single transition and derives Tex directly from the line profile, yielding a vturb. The second method assumes that two different molecules are co-spatial, which allows using their relative line widths for calculating Tkin and vturb. Finally we fitted a parametric disk model in which the physical properties of the disk are described by power laws, to compare our direct methods with previous values. Results: The two direct methods were limited to the outer r > 40 au disk because of beam smear. The direct method found vturb to range from ≈130 m s-1 at 40 au, and to drop to ≈50 m s-1 in the outer disk, which is qualitatively recovered with the parametric model fitting. This corresponds to roughly 0.2-0.4 cs. CN was found to exhibit strong non-local thermal equilibrium effects outside r ≈ 140 au, so that vturb was limited to within this radius. The assumption that CN and CS are co-spatial is consistent with observed line widths only within r ≲ 100 au, within which vturb was found to drop from 100 m s-1 (≈0.4 cs) to zero at 100 au. The parametric model yielded a nearly constant 50 m s-1 for CS (0.2-0.4 cs). We demonstrate that absolute flux calibration is and will be the limiting factor in all studies of turbulence using a single molecule. Conclusions: The magnitude of the dispersion is comparable with or below that predicted by the magneto-rotational instability theory. A more precise comparison would require reaching an absolute calibration precision of about 3%, or finding a suitable combination of light and heavy molecules that are co-located in the disk. The reduced

  8. Water around IRAS 15398-3359 observed with ALMA

    NASA Astrophysics Data System (ADS)

    Bjerkeli, P.; Jørgensen, J. K.; Bergin, E. A.; Frimann, S.; Harsono, D.; Jacobsen, S. K.; Lindberg, J. E.; Persson, M.; Sakai, N.; van Dishoeck, E. F.; Visser, R.; Yamamoto, S.

    2016-10-01

    Context. Understanding how protostars accrete their mass is one of the fundamental problems of star formation. High dust column densities and complex kinematical structures make direct observations challenging. Moreover, direct observations only provide a snapshot. Chemical tracers provide an interesting alternative to characterise the infall histories of protostars. Aims: We aim to map the distribution and kinematics of gaseous water towards the low-mass embedded protostar IRAS 15398-3359. Previous observations of H13CO+ showed a depression in the abundance towards IRAS 15398-3359. This is a sign of destruction of HCO+ by an enhanced presence of gaseous water in an extended region, possibly related to a recent burst in the accretion. Direct observations of water vapour can determine the exact extent of the emission and confirm the hypothesis that HCO+ is indeed a good tracer of the water snow-line. Methods: IRAS 15398-3359 was observed using the Atacama Large Millimeter/submillimeter Array (ALMA) at 0.5″ resolution in two setups at 390 and 460 GHz. Maps of HDO (101-000) and were taken simultaneously with observations of the CS (8-7) and N2H+ (5-4) lines and continuum at 0.65 and 0.75 mm. The maps were interpreted using dust radiative transfer calculations of the protostellar infalling envelope with an outflow cavity. Results: HDO is clearly detected and extended over the scales of the H13CO+ depression, although it is displaced by 500 AU in the direction of the outflow. HO is tentatively detected towards the red-shifted outflow lobe, but otherwise it is absent from the mapped region, which suggests that temperatures are low. Although we cannot entirely exclude a shock origin, this indicates that another process is responsible for the water emission. Conclusions: Based on the temperature structure obtained from dust radiative transfer models, we conclude that the water was most likely released from the grains in an extended hour-glass configuration during a

  9. ALMA finds dew drops in the dusty spider's web

    NASA Astrophysics Data System (ADS)

    Gullberg, Bitten; Lehnert, Matthew D.; De Breuck, Carlos; Branchu, Steve; Dannerbauer, Helmut; Drouart, Guillaume; Emonts, Bjorn; Guillard, Pierre; Hatch, Nina; Nesvadba, Nicole P. H.; Omont, Alain; Seymour, Nick; Vernet, Joël

    2016-06-01

    We present 0.̋5 resolution ALMA detections of the observed 246 GHz continuum, [CI] 3P2→3P1 fine structure line ([CI]2-1), CO(7-6), and H2O lines in the z = 2.161 radio galaxy MRC1138-262, the so-called Spiderweb galaxy. We detect strong [CI]2-1 emission both at the position of the radio core, and in a second component ~4 kpc away from it. The 1100 km s-1 broad [CI]2-1 line in this latter component, combined with its H2 mass of 1.6 × 1010 M⊙, implies that this emission must come from a compact region <60 pc, possibly containing a second active galactic nucleus (AGN). The combined H2 mass derived for both objects, using the [CI]2-1 emission, is 3.3 × 1010 M⊙. The total CO(7-6)/[CI]2-1 line flux ratio of 0.2 suggests a low excitation molecular gas reservoir and/or enhanced atomic carbon in cosmic ray dominated regions. We detect spatially-resolved H2O 211-202 emission - for the first time in a high-z unlensed galaxy - near the outer radio lobe to the east, and near the bend of the radio jet to the west of the radio galaxy. No underlying 246 GHz continuum emission is seen at either position. We suggest that the H2O emission is excited in the cooling region behind slow (10-40 km s-1) shocks in dense molecular gas (103-5 cm-3). The extended water emission is likely evidence of the radio jet's impact on cooling and forming molecules in the post-shocked gas in the halo and inter-cluster gas, similar to what is seen in low-z clusters and other high-z radio galaxies. These observations imply that the passage of the radio jet in the interstellar and inter-cluster medium not only heats gas to high temperatures, as is commonly assumed or found in simulations, but also induces cooling and dissipation, which can lead to substantial amounts of cold dense molecular gas. The formation of molecules and strong dissipation in the halo gas of MRC1138-262 may explain both the extended diffuse molecular gas and the young stars observed around MRC1138-262. The reduced data cubes

  10. Multimolecule ALMA observations toward the Seyfert 1 galaxy NGC 1097

    NASA Astrophysics Data System (ADS)

    Martín, S.; Kohno, K.; Izumi, T.; Krips, M.; Meier, D. S.; Aladro, R.; Matsushita, S.; Takano, S.; Turner, J. L.; Espada, D.; Nakajima, T.; Terashima, Y.; Fathi, K.; Hsieh, P.-Y.; Imanishi, M.; Lundgren, A.; Nakai, N.; Schinnerer, E.; Sheth, K.; Wiklind, T.

    2015-01-01

    Context. The nearby Sy 1 galaxy NGC 1097 represents an ideal laboratory for exploring the molecular chemistry in the surroundings of an active galactic nucleus (AGN). Aims: Exploring the distribution of different molecular species allows us to understand the physical processes affecting the interstellar medium both in the AGN vicinity and in the outer star forming molecular ring. Methods: We carried out 3 mm ALMA observations that include seven different molecular species, namely HCN, HCO+, CCH, CS, HNCO, SiO, HC3N, and SO, as well as the 13C isotopologues of the first two. Spectra were extracted from selected positions and all species were imaged over the central 2 kpc (~30'') of the galaxy at a resolution of ~2.2'' × 1.5'' (150 pc × 100 pc). Results: HCO+ and CS appear to be slightly enhanced in the star forming ring. CCH shows the largest variations across NGC 1097 and is suggested to be a good tracer of both obscured and early stage star formation. HNCO, SiO, and HC3N are significantly enhanced in the inner circumnuclear disk surrounding the AGN. Conclusions: Differences in the molecular abundances are observed between the star forming ring and the inner circumnuclear disk. We conclude that the HCN/HCO+ and HCN/CS differences observed between AGN-dominated and starburst (SB) galaxies are not due to a HCN enhancement due to X-rays, but rather this enhancement is produced by shocked material at distances of 200 pc from the AGN. Additionally, we claim that lower HCN/CS is a combination of a small underabundance of CS in AGNs, together with excitation effects, where a high density gas component (~106 cm-3) may be more prominent in SB galaxies. However, the most promising are the differences found among the dense gas tracers that, at our modest spatial resolution, seem to outline the physical structure of the molecular disk around the AGN. In this picture, HNCO probes the well-shielded gas in the disk, surrounding the dense material moderately exposed to the X

  11. The dynamics of massive starless cores with ALMA

    SciTech Connect

    Tan, Jonathan C.; Kong, Shuo; Butler, Michael J.; Caselli, Paola; Fontani, Francesco

    2013-12-20

    How do stars that are more massive than the Sun form, and thus how is the stellar initial mass function (IMF) established? Such intermediate- and high-mass stars may be born from relatively massive pre-stellar gas cores, which are more massive than the thermal Jeans mass. The turbulent core accretion model invokes such cores as being in approximate virial equilibrium and in approximate pressure equilibrium with their surrounding clump medium. Their internal pressure is provided by a combination of turbulence and magnetic fields. Alternatively, the competitive accretion model requires strongly sub-virial initial conditions that then lead to extensive fragmentation to the thermal Jeans scale, with intermediate- and high-mass stars later forming by competitive Bondi-Hoyle accretion. To test these models, we have identified four prime examples of massive (∼100 M {sub ☉}) clumps from mid-infrared extinction mapping of infrared dark clouds. Fontani et al. found high deuteration fractions of N{sub 2}H{sup +} in these objects, which are consistent with them being starless. Here we present ALMA observations of these four clumps that probe the N{sub 2}D{sup +} (3-2) line at 2.''3 resolution. We find six N{sub 2}D{sup +} cores and determine their dynamical state. Their observed velocity dispersions and sizes are broadly consistent with the predictions of the turbulent core model of self-gravitating, magnetized (with Alfvén Mach number m{sub A} ∼ 1) and virialized cores that are bounded by the high pressures of their surrounding clumps. However, in the most massive cores, with masses up to ∼60 M {sub ☉}, our results suggest that moderately enhanced magnetic fields (so that m{sub A} ≅ 0.3) may be needed for the structures to be in virial and pressure equilibrium. Magnetically regulated core formation may thus be important in controlling the formation of massive cores, inhibiting their fragmentation, and thus helping to establish the stellar IMF.

  12. Employment of Baccalaureate Graduates: The Effect of Institutional Reputation, Location, and Executive Alma Mater.

    ERIC Educational Resources Information Center

    Stewart, Barbara L.

    The effect of institutional reputation, college and employer location, and employer's alma mater on hiring practices when selecting baccalaureate-level college graduates was studied. Questionnaires were returned by 91 randomly selected companies. While institutional prestige was not a significant factor in employee selection, accreditation was…

  13. ESO Signs Largest-Ever European Industrial Contract For Ground-Based Astronomy Project ALMA

    NASA Astrophysics Data System (ADS)

    2005-12-01

    ESO, the European Organisation for Astronomical Research in the Southern Hemisphere, announced today that it has signed a contract with the consortium led by Alcatel Alenia Space and composed also of European Industrial Engineering (Italy) and MT Aerospace (Germany), to supply 25 antennas for the Atacama Large Millimeter Array (ALMA) project, along with an option for another seven antennas. The contract, worth 147 million euros, covers the design, manufacture, transport and on-site integration of the antennas. It is the largest contract ever signed in ground-based astronomy in Europe. The ALMA antennas present difficult technical challenges, since the antenna surface accuracy must be within 25 microns, the pointing accuracy within 0.6 arc seconds, and the antennas must be able to be moved between various stations on the ALMA site. This is especially remarkable since the antennas will be located outdoor in all weather conditions, without any protection. Moreover, the ALMA antennas can be pointed directly at the Sun. ALMA will have a collecting area of more than 5,600 square meters, allowing for unprecedented measurements of extremely faint objects. The signing ceremony took place on December 6, 2005 at ESO Headquarters in Garching, Germany. "This contract represents a major milestone. It allows us to move forward, together with our American and Japanese colleagues, in this very ambitious and unique project," said ESO's Director General, Dr. Catherine Cesarsky. "By building ALMA, we are giving European astronomers access to the world's leading submillimetre facility at the beginning of the next decade, thereby fulfilling Europe's desire to play a major role in this field of fundamental research." Pascale Sourisse, Chairman and CEO of Alcatel Alenia Space, said: "We would like to thank ESO for trusting us to take on this new challenge. We are bringing to the table not only our recognized expertise in antenna development, but also our long-standing experience in

  14. Solar ALMA observations - A revolutionizing new view at our host star

    NASA Astrophysics Data System (ADS)

    Wedemeyer, Sven; Brajsa, Roman; Bastian, Timothy S.; Barta, Miroslav; Hales, Antonio; Yagoubov, Pavel; Hudson, Hugh; Loukitcheva, Maria; Fleishman, Gregory

    2015-08-01

    Observations of the Sun with the Atacama Large Millimeter/submillimeter Array (ALMA) have a large potential for revolutionizing our understanding of our host star with far reaching implications for stars in general. The radiation emitted at ALMA wavelengths originates mostly from the chromosphere - a complex and dynamic layer between the photosphere and the corona, which plays an important role in the transport of energy and matter and the heating of the outer layers of the solar atmosphere.Despite decades of intensive research, the chromosphere is still elusive and challenging to observe owing to the complicated formation mechanisms of currently available diagnostics. ALMA will change the scene substantially as it serves as a nearly linear thermometer at high spatial, temporal, and spectral resolution, enabling us to study the complex interaction of magnetic fields and shock waves and yet-to-be-discovered dynamical processes. Furthermore, radio recombination and molecular lines may have great diagnostic potential but need to be investigated first. These unprecedented capabilities promise important new findings for a large range of topics in solar physics including the structure, dynamics and energy balance of quiet Sun regions, active regions and sunspots, flares and prominences. As a part of ongoing development studies, an international network has been initiated, which aims at defining and preparing key solar science with ALMA through simulation studies: SSALMON -- Solar Simulations for the Atacama Large Millimeter Observatory Network (http://ssalmon.uio.no). Here, we give an overview of potential science cases.

  15. Generic Abstraction of Hardware Control Based on the ALMA Common Software

    NASA Astrophysics Data System (ADS)

    Jeram, B.; Chiozzi, G.; Ibsen, J.; Cirami, R.; Pokorny, M.; Muders, D.; Wischolek, D.

    2004-07-01

    The ALMA Common Software (ACS) is a CORBA-based framework that provides a common and homogeneous infrastructure for the whole ALMA software, from high-level data flow applications down to instrument control (Schwarz et al., 2004). This paper focuses on ACS support for the development of Control System applications. In this domain, ACS provides a generic abstraction of hardware control and monitor points that is independent of the software underneath. This abstraction layer is coupled to the hardware using the DevIO (Device Input/Output) interface, based on the Bridge design pattern. Application developers have to implement DevIO classes that handle the details of the communication with the hardware. ACS itself provides a default DevIO implementation which simply writes and reads into/from a memory location. Currently there are two other major DevIO implementations available: a CAN bus communication, used by ALMA, and a socket based implementation used by the Atacama Pathfinder EXperiment (APEX) project. In spite of using different hardware and control electronics, the DevIO abstraction allows the ALMA and APEX projects to have the same device architecture down to the level of the DevIO implementation.

  16. High resolution ALMA observations of dense molecular medium in the central regions of active galaxies

    NASA Astrophysics Data System (ADS)

    Kohno, Kotaro

    2015-08-01

    I will present recent ALMA results on the dense molecular gas in the central regions of local active galaxies, including NGC 1068, NGC 1097, and NGC 7469, hosting both AGN and circumnuclear starburst regions. Impact of X-ray radiation, outflows, and shocks from active nuclei on the physical and chemical properties of the surrouding dense molecular medium will be discussed.

  17. Equilibrium chemical reaction of supersonic hydrogen-air jets (the ALMA computer program)

    NASA Technical Reports Server (NTRS)

    Elghobashi, S.

    1977-01-01

    The ALMA (axi-symmetrical lateral momentum analyzer) program is concerned with the computation of two dimensional coaxial jets with large lateral pressure gradients. The jets may be free or confined, laminar or turbulent, reacting or non-reacting. Reaction chemistry is equilibrium.

  18. The ALMA archive and its place in the astronomy of the future

    NASA Astrophysics Data System (ADS)

    Stoehr, Felix; Lacy, Mark; Leon, Stephane; Muller, Erik; Manning, Alisdair; Moins, Christophe; Jenkins, Dustin

    2014-07-01

    The Atacama Large Millimeter/submillimeter Array (ALMA), an international partnership of Europe, North America and East Asia in cooperation with the Republic of Chile, is the largest astronomical project in existence. While ALMA's capabilities are ramping up, Early Science observations have started. The ALMA Archive is at the center of the operations of the telescope array and is designed to manage the 200 TB of data that will be taken each year, once the observatory is in full operations. We briefly describe design principles. The second part of this paper focuses on how astronomy is likely to evolve as the amount and complexity of data taken grows. We argue that in the future observatories will compete for astronomers to work with their data, that observatories will have to reorient themselves to from providing good data only to providing an excellent end-to-end user-experience with all its implications, that science-grade data-reduction pipelines will become an integral part of the design of a new observatory or instrument and that all this evolution will have a deep impact on how astronomers will do science. We show how ALMA's design principles are in line with this paradigm.

  19. Massive and dusty Hα emitters in protocluster revealed by ALMA and JVLA

    NASA Astrophysics Data System (ADS)

    Lee, Minju

    We investigate the physical properties of Hα emitters (HAEs) associated to the protocluster 4C23.56 at z ~ 2.5 using continuum observations at submm (270 GHz) and radio (3 GHz) frequencies with Atacama Large Mm/submm Array (ALMA) and K. Jansky Very Large Array (JVLA). For more details see Lee et al. (in prep).

  20. The ALMA Data Mining Toolkit I: Archive Setup and User Usage

    NASA Astrophysics Data System (ADS)

    Teuben, P.; Pound, M.; Mundy, L.; Looney, L.; Friedel, D. N.

    2014-05-01

    We report on an ALMA development study and project where we employ a novel approach to add data and data descriptors to ALMA archive data and allowing further flexible data mining on retrieved data. We call our toolkit ADMIT (the ALMA Data Mining Toolkit) that works within the Python based CASA environment. What is described here is a design study, with some exiting toy code to prove the concept. After ingestion of science ready datacubes, ADMIT will compute a number of basic and advanced data products, and their descriptors. Examples of such data products are cube statistics, line identification tables, line cubes, moment maps, an integrated spectrum, overlap integrals and feature extraction tables. Together with a descriptive XML file, a small number of visual aids are added to a ZIP file that is deposited into the archive. Large datasets (such as line cubes) will have to be rederived by the user once they have also downloaded the actual ALMA Data Products, or via VO services if available. ADMIT enables the user to rederive all its products with different methods and parameters, and compare archive product with their own.

  1. NRAO welcomes new Head of the North American ALMA Science Center

    NASA Astrophysics Data System (ADS)

    2008-09-01

    The National Radio Astronomy Observatory (NRAO) has announced the appointment of Dr. Carol Jean Lonsdale as the Observatory's new Assistant Director for the North American ALMA Science Center (NAASC). As NAASC head, Lonsdale will lead the team that will enable North American astronomers to exploit the capabilities of the Atacama Large Millimeter/submillimeter Array (ALMA), a powerful new international astronomical facility under construction in the high-altitude Atacama Desert of northeastern Chile. Dr. Carol Lonsdale Dr. Carol Lonsdale CREDIT: NRAO/AUI/NSF "With ALMA, our understanding of such crucial processes as the formation of galaxies, stars, and planetary systems is going to take a giant leap. I look forward to leading the people here at NRAO who are working to make ALMA accessible to a wide range of science users," said Lonsdale. Lonsdale comes to NRAO with an extensive background in overseeing large astronomical projects. She has held senior positions at the Infrared Processing and Analysis Center (IPAC) of the California Institute of Technology, where she served as Senior Research Scientist, Head of Science Staff, and Manager of the Wide-Field Infrared Explorer and Infrared Science Archive. She has been a science team member on the Infrared-Red Astronomy Satellite, Two Micron All Sky Survey, Wide-Field Infrared Survey Explorer, and other missions. "Carol brings a new dimension to the NAASC, with broad experience in user support of space infrared missions at IPAC and world-class scientific leadership in the study of star forming galaxies," said Christopher Carilli, who headed the NAASC prior to his new appointment as NRAO Chief Scientist. When completed in 2012, ALMA will be an array of at least 66 high-precision radio telescopes that will image faint millimeter- and submillimeter-wavelength light emitted by cold objects in the Universe, such as molecular clouds where stars are forming. It will also study warmer objects in the early Universe whose infrared

  2. The ALMA common software: a developer-friendly CORBA-based framework

    NASA Astrophysics Data System (ADS)

    Chiozzi, Gianluca; Jeram, Bogdan; Sommer, Heiko; Caproni, Alessandro; Plesko, Mark; Sekoranja, Matej; Zagar, Klemen; Fugate, David W.; Di Marcantonio, Paolo; Cirami, Roberto

    2004-09-01

    The ALMA Common Software (ACS) is a set of application frameworks built on top of CORBA. It provides a common software infrastructure to all partners in the ALMA collaboration. The usage of ACS extends from high-level applications such as the Observation Preparation Tool [7] that will run on the desk of astronomers, down to the Control Software [6] domain. The purpose of ACS is twofold: from a system perspective, it provides the implementation of a coherent set of design patterns and services that will make the whole ALMA software [1] uniform and maintainable; from the perspective of an ALMA developer, it provides a friendly programming environment in which the complexity of the CORBA middleware and other libraries is hidden and coding is drastically reduced. The evolution of ACS is driven by a long term development plan, however on the 6-months release cycle the plan is adjusted based on incoming requests from ALMA subsystem development teams. ACS was presented at SPIE 2002[2]. In the two years since then, the core services provided by ACS have been extended, while the coverage of the application framework has been increased to satisfy the needs of high-level and data flow applications. ACS is available under the LGPL public license. The patterns implemented and the services provided can be of use also outside the astronomical community; several projects have already shown their interest in ACS. This paper presents the status of ACS and the progress over the last two years. Emphasis is placed on showing how requests from ACS users have driven the selection of new features.

  3. Bulk data transfer distributer: a high performance multicast model in ALMA ACS

    NASA Astrophysics Data System (ADS)

    Cirami, R.; Di Marcantonio, P.; Chiozzi, G.; Jeram, B.

    2006-06-01

    A high performance multicast model for the bulk data transfer mechanism in the ALMA (Atacama Large Millimeter Array) Common Software (ACS) is presented. The ALMA astronomical interferometer will consist of at least 50 12-m antennas operating at millimeter wavelength. The whole software infrastructure for ALMA is based on ACS, which is a set of application frameworks built on top of CORBA. To cope with the very strong requirements for the amount of data that needs to be transported by the software communication channels of the ALMA subsystems (a typical output data rate expected from the Correlator is of the order of 64 MB per second) and with the potential CORBA bottleneck due to parameter marshalling/de-marshalling, usage of IIOP protocol, etc., a transfer mechanism based on the ACE/TAO CORBA Audio/Video (A/V) Streaming Service has been developed. The ACS Bulk Data Transfer architecture bypasses the CORBA protocol with an out-of-bound connection for the data streams (transmitting data directly in TCP or UDP format), using at the same time CORBA for handshaking and leveraging the benefits of ACS middleware. Such a mechanism has proven to be capable of high performances, of the order of 800 Mbits per second on a 1Gbit Ethernet network. Besides a point-to-point communication model, the ACS Bulk Data Transfer provides a multicast model. Since the TCP protocol does not support multicasting and all the data must be correctly delivered to all ALMA subsystems, a distributer mechanism has been developed. This paper focuses on the ACS Bulk Data Distributer, which mimics a multicast behaviour managing data dispatching to all receivers willing to get data from the same sender.

  4. Assembly, integration, and verification (AIV) in ALMA: series processing of array elements

    NASA Astrophysics Data System (ADS)

    Lopez, Bernhard; Jager, Rieks; Whyborn, Nicholas D.; Knee, Lewis B. G.; McMullin, Joseph P.

    2012-09-01

    The Atacama Large Millimeter/submillimeter Array (ALMA) is a joint project between astronomical organizations in Europe, North America, and East Asia, in collaboration with the Republic of Chile. ALMA will consist of at least 54 twelve-meter antennas and 12 seven-meter antennas operating as an aperture synthesis array in the (sub)millimeter wavelength range. It is the responsibility of ALMA AIV to deliver the fully assembled, integrated, and verified antennas (array elements) to the telescope array. After an initial phase of infrastructure setup AIV activities began when the first ALMA antenna and subsystems became available in mid 2008. During the second semester of 2009 a project-wide effort was made to put in operation a first 3- antenna interferometer at the Array Operations Site (AOS). In 2010 the AIV focus was the transition from event-driven activities towards routine series production. Also, due to the ramp-up of operations activities, AIV underwent an organizational change from an autonomous department into a project within a strong matrix management structure. When the subsystem deliveries stabilized in early 2011, steady-state series processing could be achieved in an efficient and reliable manner. The challenge today is to maintain this production pace until completion towards the end of 2013. This paper describes the way ALMA AIV evolved successfully from the initial phase to the present steady-state of array element series processing. It elaborates on the different project phases and their relationships, presents processing statistics, illustrates the lessons learned and relevant best practices, and concludes with an outlook of the path towards completion.

  5. ALMA observations of supernova 1987A mixing, nucleosynthesis and dynamics of the ejecta

    NASA Astrophysics Data System (ADS)

    Matsuura, M.; Indebetouw, R.; Kamenetzky, J.; Abellan, F.; Barlow, M. J.; Bujarrabal, V.; Marcaide, J.; McCray, R.; Woosley, S.

    2016-06-01

    ALMA observations of supernova 1987A mixing, nucleosynthesis and dynamics of the ejecta We present a molecular line survey for supernova 1987A, using the Atacama Large Millimetre / submillimetre Array (ALMA). We detected the CO, SiO, HCO+ and SO molecular lines from the ejecta. Those molecules can probe three different aspects of the SN 1987A ejecta: 1. Footprints of mixing and dynamics in the early days after the supernova explosion, 2. Molecular chemistry in the last twenty-five years 3. Explosive nuclear synthesis, using isotopologues, hence isotope ratios The extent of mixing after supernova explosions is still not well understood. Molecules can provide a new tool to probe this: microscopic mixing stirs the elements from different layers of nuclear-reaction zones in the stellar core, opening the possibility to form molecules with elements from different nuclearburning zones. This process should have increased the abundance of HCO+, making it feasible now for ALMA to detect them. Our new ALMA observations have revealed several interesting features of the molecular gas. For instance, the SiO molecular lines clearly show dips in the line profile, while the CO lines do not. The different line profiles suggest that SiO and CO are spatially distributed at different locations. This could potentially be caused by different dynamics taking place immediately after the explosion, as SN hydrodynamical simulations suggest. ALMA spectra contain lines of isotopologues, which are molecules composed of atoms with different isotopes, and allow us to estimate the isotope ratios. Our upper limits of 28Si/29Si and 28Si/30Si are consistent with theoretically predicted values for SN 1987A. However, the ratios are at least a factor of two larger than isotopes measured in SN-associated pre-solar grains. Such thing could support the theory that neutron-rich isotopes are produced less efficiently in low metallicity environments, such as the Large Magellanic Cloud, where SN 1987A is

  6. Further ALMA observations and detailed modeling of the Red Rectangle

    NASA Astrophysics Data System (ADS)

    Bujarrabal, V.; Castro-Carrizo, A.; Alcolea, J.; Santander-García, M.; van Winckel, H.; Sánchez Contreras, C.

    2016-09-01

    Aims: We aim to study the rotating and expanding gas in the Red Rectangle, which is a well known bipolar nebula surrounding a double stellar system whose primary is a post-asymptotic giant branch (post-AGB) star. We analyze the properties of both components and the relation between them. Rotating disks have been very elusive in post-AGB nebulae, in which gas is almost always found to be in expansion. Methods: We present new high-quality ALMA observations of this source in C17O J = 6-5 and H13CN J = 4-3 line emission and results from a new reduction of already published 13CO J = 3-2 data. A detailed model fitting of all the molecular line data, also discussing previous maps and single-dish observations of lines of CO, CII, and CI, was performed using a sophisticated code that includes an accurate nonlocal treatment of radiative transfer in 2D (assuming axial symmetry). These observations (of low- and high-opacity lines requiring various degrees of excitation) and the corresponding modeling allowed us to deepen the analysis of the nebular properties. We also stress the uncertainties, particularly in the determination of the boundaries of the CO-rich gas and some properties of the outflow. Results: We confirm the presence of a rotating equatorial disk and an outflow, which is mainly formed of gas leaving the disk. The mass of the disk is ~0.01 M⊙, and that of the CO-rich outflow is around ten times smaller. High temperatures of ≳100 K are derived for most components. From comparison of the mass values, we roughly estimate the lifetime of the rotating disk, which is found to be of about 10 000 yr. Taking data of a few other post-AGB composite nebulae into account, we find that the lifetimes of disks around post-AGB stars typically range between about 5000 and more than 20 000 yr. The angular momentum of the disk is found to be high, ~9 M⊙ AU km s-1, which is comparable to that of the stellar system at present. Our observations of H13CN show a particularly wide

  7. ALMA Partners Award Prototype Antenna Contracts in Europe and the USA

    NASA Astrophysics Data System (ADS)

    2000-03-01

    The European and U.S. partners in the Atacama Large Millimeter Array (ALMA) project have awarded contracts to firms in Italy and the USA, respectively, for two prototype antennas. ALMA is a planned telescope array, expected to consist of 64 millimeter-wave antennas with 12-meter diameter dishes, cf. ESO Press Release 09/99 and ESO PR Video Clip 08/99. The array will be built at a high-altitude, extremely dry mountain site in Chile's Atacama desert, and is scheduled to be completed sometime in this decade. The European partners contracted with the consortium of European Industrial Engineering and Costamasnaga (Mestre, Italy), on February 21, 2000, for the production of one prototype ALMA antenna. On February 22, 2000, Associated Universities Inc. signed a contract with Vertex Antenna Systems (Santa Clara, California), for construction of another prototype antenna. The two antennas must meet identical specifications, but will inherently be of different designs. This will ensure that the best possible technologies are incorporated into the final production antennas. Several technical challenges must be met for the antennas to perform to ALMA specifications. Each antenna must have extremely high surface accuracy (25 µm, or one-third the diameter of a human hair, over the entire 12-meter diameter). This means that, when completed, the surface accuracy of the ALMA dishes will be 20 times greater than that of the Very Large Array (VLA) antennas near Socorro (New Mexico, USA), and about 50 times greater than dish antennas for communications or radar. The ALMA antennas must also have extremely high pointing accuracy (0.6 arcseconds). An additional challenge is that the antennas, when installed at the ALMA site in Chile, will be exposed to the ravages of weather at 5000 m elevation. All previous millimeter-wavelength antennas that meet such exacting specifications for surface accuracy and pointing accuracy have been housed within telescope enclosures. The U.S. and European

  8. Diversity of flavin-binding monooxygenase genes (almA) in marine bacteria capable of degradation long-chain alkanes.

    PubMed

    Wang, Wanpeng; Shao, Zongze

    2012-06-01

    Many bacteria have been reported as degraders of long-chain (LC) n-alkanes, but the mechanism is poorly understood. Flavin-binding monooxygenase (AlmA) was recently found to be involved in LC-alkane degradation in bacteria of the Acinetobacter and Alcanivorax genera. However, the diversity of this gene and the role it plays in other bacteria remains unclear. In this study, we surveyed the diversity of almA in marine bacteria and in bacteria found in oil-enrichment communities. To identify the presence of this gene, a pair of degenerate PCR primers were was designed based on conserved motifs of the almA gene sequences in public databases. Using this approach, we identified diverse almA genes in the hydrocarbon-degrading bacteria and in bacterial communities from the surface seawater of the Xiamen coastal area, the South China Sea, the Indian Ocean, and the Atlantic Ocean. As a result, almA was positively detected in 35 isolates belonging to four genera, and a total of 39 different almA sequences were obtained. Five isolates were confirmed to harbor two to three almA genes. From the Xiamen coastal area and the Atlantic Ocean oil-enrichment communities, a total of 60 different almA sequences were obtained. These sequences mainly formed two clusters in the phylogenetic tree, named Class I and Class II, and these shared 45-56% identity at the amino acid level. Class I contained 11 sequences from bacteria represented by the Salinisphaera and Parvibaculum genera. Class II was larger and more diverse, and it was composed of 88 sequences from Proteobacteria, Gram-negative bacteria, and the enriched bacterial communities. These communities were represented by the Alcanivorax and Marinobacter genera, which are the two most popular genera hosting the almA gene. AlmA was also detected across a wide geographical range, as determined by the origin of the bacterial host. Our results demonstrate the diversity of almA and confirm its high rate of occurrence in hydrocarbon

  9. The Peculiar Distribution of CH3CN in IRC +10216 Seen by ALMA

    NASA Astrophysics Data System (ADS)

    Agúndez, M.; Cernicharo, J.; Quintana-Lacaci, G.; Velilla Prieto, L.; Castro-Carrizo, A.; Marcelino, N.; Guélin, M.

    2015-12-01

    IRC +10216 is a circumstellar envelope around a carbon-rich evolved star which contains a large variety of molecules. According to interferometric observations, molecules are distributed either concentrated around the central star or as a hollow shell with a radius of ∼15″. We present ALMA Cycle 0 band 6 observations of the J = 14 – 13 rotational transition of CH3CN in IRC +10216, obtained with an angular resolution of 0.″76 × 0.″61. The bulk of the emission is distributed as a hollow shell located at just ∼2″ from the star, with a void of emission in the central region up to a radius of ∼1″. This spatial distribution is markedly different from those found to date in this source for other molecules. Our analysis indicates that methyl cyanide is not formed in either the stellar photosphere or far in the outer envelope, but at radial distances as short as 1″–2″, reaching a maximum abundance of ∼0.02 molecules cm‑3 at 2″ from the star. Standard chemical models of IRC +10216 predict that the bulk of CH3CN molecules should be present at a radius of ∼15″ where other species such as polyyne radicals and cyanopolyynes are observed, with an additional inner component within 1″ from the star. The non-uniform structure of the circumstellar envelope and grain surface processes are discussed as possible causes of the peculiar distribution of methyl cyanide in IRC +10216. Based on observations carried out with ALMA and the IRAM 30 m Telescope. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. IRAM is supported by INSU/CNRS (France), MPG (Germany), and IGN (Spain). This paper makes use of the following ALMA data: ADS/JAO.ALMA#2011.0.00229.S.

  10. Transparent XML Binding using the ALMA Common Software (ACS) Container/Component Framework

    NASA Astrophysics Data System (ADS)

    Sommer, H.; Chiozzi, G.; Fugate, D.; Sekoranja, M.

    2004-07-01

    ALMA software, from high-level data flow applications down to instrument control, is built using the ACS framework. The common architecture and infrastructure used for the whole ALMA software is presented at this conference in (Schwarz, Farris, & Sommer 2004). ACS offers a CORBA-based container/component model and supports the exchange and persistence of XML data. For the Java programming language, the container integrates transparently the use of type-safe Java binding classes to let applications conveniently work with XML transfer objects without having to parse or serialize them. This paper will show how the ACS container/component architecture serves to pass complex data structures, such as observation meta-data, between heterogeneous applications.

  11. ALMA observation of high-z extreme star-forming environments discovered by Planck/Herschel

    NASA Astrophysics Data System (ADS)

    Kneissl, R.

    2016-05-01

    The Comic Microwave Background satellite Planck with its High Frequency Instrument has surveyed the mm/sub-mm sky in six frequency channels from 100 to 900 GHz. A sample of 228 cold sources of the Cosmic Infrared Background was observed in follow-up with Herschel SPIRE. The majority of sources appear to be over-densities of star-forming galaxies matching the size of high-z proto-cluster regions, while a 3% fraction are individual bright, lensed galaxies. A large observing program is underway with the aim of resolving the regions into the constituent members of the Planck sources. First ALMA data have been received on one Planck/Herschel proto-cluster candidate, showing the expected large over-abundance of bright mm/sub-mm sources within the cluster region. ALMA long baseline data of the brightest lensed galaxy in the sample with > 1 Jy at 350 μm are also forthcoming.

  12. VizieR Online Data Catalog: VY CMa ALMA NaCl images (Decin+, 2016)

    NASA Astrophysics Data System (ADS)

    Decin, L.; Richards, A. M. S.; Millar, T. J.; Baudry, A.; de, Beck E.; Homan, W.; Smith, N.; van de Sande, M.; Walsh, C.

    2016-07-01

    VY CMa was observed for ALMA Science Verification on 2013 16-19 August using 16-20 12-m antennas on baselines from 0.014-2.7km. The main objective was to map the H2O maser lines at 321 and 325GHz (Band 7) and 658GHz (Band 9), but several thermal lines identified with various rotational transitions of NaCl, TiO2, SO2, and SiO were also present in the spectral setting in addition to the continuum data. Four NaCl lines in the ground or first vibrational state are covered in the ALMA band 7 data. All of them are detected, albeit only two are unblended (see Table 1). (3 data files).

  13. De Herschel à Alma. Les galaxies dévoilent enfin leurs secrets.

    NASA Astrophysics Data System (ADS)

    Elbaz, David

    2016-08-01

    With deep surveys, one can measure the amount of stars born in slices of the Universe and infer a "cosmic rate of star formation." The latest estimates from the Herschel satellite show a rapid drop of star formation in galaxies since ten billion years. To understand the cause of this fall, we can now measure the interstellar reservoirs of galaxies by combining observations from Herschel and the millimeter interferometer ALMA. Early results suggest that this fall comes from the rapid consumption of interstellar matter which served as reservoir to galaxies. Thanks to the technique of interferometry, ALMA can map interstellar dust within galaxies observed at the time of the peak of cosmic star formation, ten billion years ago. We discover that the stars of the most massive galaxies are born not only at very high rates but also with an extreme concentration.

  14. The ALMA Band 3 (84-116 GHz) receiver production plan

    NASA Astrophysics Data System (ADS)

    Yeung, Keith; Claude, Stéphane; Loop, David

    2008-07-01

    The NRC Herzberg Institute of Astrophysics (NRC-HIA) is currently responsible to contribute Band 3 (84-116 GHz) receivers to the international ALMA project - a partnership involving North America, Europe and, now, Asia. Not only are the technical requirements for these receivers far more stringent than those for any existing radio astronomy receivers operating at these frequencies, but the delivery schedule for these receivers is equally challenging. Since the Asian partnership joined the ALMA project in 2006, NRC-HIA has been asked to deliver an additional 11 cartridges, for a total of 73 units. Some of these new cartridges will be used for the ALMA Compact Array (ACA) and others as spares. Moreover, the project has also requested that these additional cartridges be delivered in the same time period as the original 62 units. To meet this requirement, production must increase from the existing rate of one unit every four weeks to one every two, taxing the existing production infrastructure at NRC-HIA. Additional test facilities and human resources must be planned to sustain the required production rate over the next several years. Industrial involvement is one of the important elements in our production plan. In order to supplement the existing human resources at NRC-HIA, we are planning to outsource a number of low-risk and labor-intensive tasks to industry. However, NRC-HIA will retain overall project management responsibility and will conduct all the cartridge integration and acceptance test activities in-house. This paper focuses on the resource estimation, planning and project management required to deliver the Band 3 receivers to the ALMA project on time and on budget.

  15. ALMA observations of the not-so detached shell around the carbon AGB star R Sculptoris

    NASA Astrophysics Data System (ADS)

    Maercker, Matthias

    2016-07-01

    I present our ALMA observations of the CO emission around the carbon AGB star R Sculptoris. The data reveal the known detached shell and a previously unknown, binary induced, spiral shape. The observations confirm a formation of the shell during a thermal pulse about 2300 years ago. The full analysis of the ALMA data shows that the shell around R Scl in fact is entirely filled with molecular gas, and hence not as detached as previously thought. This has implications for the mass-loss rate evolution immediately after the pulse, indicating a much higher mass-loss rate than previously assumed. Comparing the ALMA images to our optical observations of polarised, dust scattered light, we further show that the distributions of the dust and gas coincide almost perfectly, implying a common evolution of the dust and gas, and constraining the wind-driving mechanism. The mass-loss process and amount of mass lost during the thermal pulse cycle affect the chemical evolution of the star, its lifetime on the AGB, and the return of heavy elements to the ISM. New high-resolution ALMA observations constrain the parameters of the binary system and the inner spiral, and will allow for a detailed hydrodynamical modelling of the gas and dust during and after the last thermal pulse. Our results present the only direct measurements of the thermal pulse evolution currently available. They greatly increase our understanding of this fundamental period of stellar evolution, and the implications it has for the chemical evolution of evolved stars, the ISM, and galaxie

  16. Detection of Lensing Substructure Using ALMA Observations of the Dusty Galaxy SDP.81

    NASA Astrophysics Data System (ADS)

    Hezaveh, Yashar D.; Dalal, Neal; Marrone, Daniel P.; Mao, Yao-Yuan; Morningstar, Warren; Wen, Di; Blandford, Roger D.; Carlstrom, John E.; Fassnacht, Christopher D.; Holder, Gilbert P.; Kemball, Athol; Marshall, Philip J.; Murray, Norman; Perreault Levasseur, Laurence; Vieira, Joaquin D.; Wechsler, Risa H.

    2016-05-01

    We study the abundance of substructure in the matter density near galaxies using ALMA Science Verification observations of the strong lensing system SDP.81. We present a method to measure the abundance of subhalos around galaxies using interferometric observations of gravitational lenses. Using simulated ALMA observations we explore the effects of various systematics, including antenna phase errors and source priors, and show how such errors may be measured or marginalized. We apply our formalism to ALMA observations of SDP.81. We find evidence for the presence of a M = 108.96±0.12 M ⊙ subhalo near one of the images, with a significance of 6.9σ in a joint fit to data from bands 6 and 7; the effect of the subhalo is also detected in both bands individually. We also derive constraints on the abundance of dark matter (DM) subhalos down to M ˜ 2 × 107 M ⊙, pushing down to the mass regime of the smallest detected satellites in the Local Group, where there are significant discrepancies between the observed population of luminous galaxies and predicted DM subhalos. We find hints of additional substructure, warranting further study using the full SDP.81 data set (including, for example, the spectroscopic imaging of the lensed carbon monoxide emission). We compare the results of this search to the predictions of ΛCDM halos, and find that given current uncertainties in the host halo properties of SDP.81, our measurements of substructure are consistent with theoretical expectations. Observations of larger samples of gravitational lenses with ALMA should be able to improve the constraints on the abundance of galactic substructure.

  17. Testing Wave Propagation Properties in the Solar Chromosphere with ALMA and IRIS

    NASA Astrophysics Data System (ADS)

    Fleck, Bernard; Straus, Thomas; Wedemeyer, Sven

    2016-05-01

    Waves and oscillations are interesting not only from the point of view that they can propagate energy into the chromosphere and dissipate that energy to produce non-radiative heating, they also carry information about the structure of the atmosphere in which they propagate. Since the late 80s there is substantial evidence that the chromospheric wave field is dominated by a non-propagating component, presumably resulting from wave reflection at the transition region. Observations of Doppler oscillations measured in the Ca II infrared tripet lines, Ca II K, and He 10830 all show vanishing phase lags (i.e. vanishing travel time differences) between the various lines, in particular also for frequencies above the cut-off frequency. Why is the apparent phase speed of high frequency acoustic waves in the chromosphere so high? Are these results misleading because of complex radiation transfer effects in these optically thick lines? ALMA, which acts as a linear thermometer of the solar chromosphere, will provide measurements of the local plasma conditions that should be, at least in principle, much easier to interpret. Multi-wavelength time series of ALMA observations of the temperature fluctuations of inter-network oscillations should allow travel time measurements between different heights as these disturbances propagate through the chromosphere and thus should finally settle the long-standing question about the propagation characteristics of high frequency acoustic waves in the chromosphere. We plan to combine ALMA mm-observations with high resolution IRIS observations in the Mg II h and k lines, and until ALMA observations are available, will study the expected signals using time series of mm-maps from 3D radiation hydrodynamics simulations that are being prepared within the framework of the Solar Simulations for the Atacama Large Millimeter Observatory Network (SSALMON).

  18. Detection of Lensing Substructure Using Alma Observations of the Dusty Galaxy SDP.81

    DOE PAGESBeta

    Hezaveh, Yashar D.; Dalal, Neal; Marrone, Daniel P.; Mao, Yao-Yuan; Morningstar, Warren; Wen, Di; Blandford, Roger D.; Carlstrom, John E.; Fassnacht, Christopher D.; Holder, Gilbert P.; et al

    2016-05-19

    We study the abundance of substructure in the matter density near galaxies using ALMA Science Verification observations of the strong lensing system SDP.81. We present a method to measure the abundance of subhalos around galaxies using interferometric observations of gravitational lenses. Using simulated ALMA observations we explore the effects of various systematics, including antenna phase errors and source priors, and show how such errors may be measured or marginalized. We apply our formalism to ALMA observations of SDP.81. We find evidence for the presence of a M = 108.96±0.12 M⊙ subhalo near one of the images, with a significance ofmore » 6.9σ in a joint fit to data from bands 6 and 7; the effect of the subhalo is also detected in both bands individually. We also derive constraints on the abundance of dark matter (DM) subhalos down to M ~ 2 × 107 M⊙, pushing down to the mass regime of the smallest detected satellites in the Local Group, where there are significant discrepancies between the observed population of luminous galaxies and predicted DM subhalos. We find hints of additional substructure, warranting further study using the full SDP.81 data set (including, for example, the spectroscopic imaging of the lensed carbon monoxide emission). We compare the results of this search to the predictions of ΛCDM halos, and find that given current uncertainties in the host halo properties of SDP.81, our measurements of substructure are consistent with theoretical expectations. Finally, observations of larger samples of gravitational lenses with ALMA should be able to improve the constraints on the abundance of galactic substructure.« less

  19. Poster 9: Isotopic Ratios of Carbon and Oxygen in Titan's CO using ALMA

    NASA Astrophysics Data System (ADS)

    Serigano, Joseph; Nixion, Conor A.; Cordiner, Martin A.; Irwin, Patrick G. J.; Teanby, Nick A.; Charnley, Steven B.; Lindberg, Johan E.

    2016-06-01

    The advent of the Atacama Large Millimeter/Submillimeter Array (ALMA) has provided a new and powerful facility for probing the atmospheres of solar system targets at long wavelengths (84-720 GHz) where the rotational lines of small, polar molecules are prominent. In the complex atmosphere of Titan, photochemical processes dissociate and ionize molecular nitrogen and methane in the upper atmosphere, creating a complex inventory of trace hydrocarbons and nitriles. Additionally, the existence of oxygen on Titan facilitates the synthesis of molecules of potential astrobiological importance. Utilization of ground-based submillimeter observations of Titan has proven to be a powerful tool to complement results from spacecraft observations. ALMA provides the ability to probe this region in greater detail with unprecedented spectral and spatial resolution at high sensitivity, allowing for the derivation of vertical mixing profiles, molecular detections, and observations of latitudinal and seasonal variations. Recent ALMA studies of Titan have presented spectrally and spatially-resolved maps of HNC and HC3N emission (Cordiner et al. 2014), as well as the first spectroscopic detection of ethyl cyanide (C2H5CN) in Titan's atmosphere (Cordiner et al. 2015). This poster will focus on ALMA observations of carbon monoxide (CO) and its isotopologues 13CO, C18O, and C 17O in Titan's atmosphere. Molecular abundances and the vertical atmospheric temperature profile were derived by modeling the observed emission line profiles using NEMESIS, a line-by-line radiative transfer code (Irwin et al. 2008). This study reports the first spectroscopic detection of 17O in the outer solar system with C17O detected at >8σ confidence. The abundances of these molecules and isotopic ratios of 12C/13C, 16O/18O, and 16O/17O will be presented. General implications for the history of Titan from these measurements will be discussed.

  20. Detection and mapping of organic molecules in Titan's atmosphere using ALMA

    NASA Astrophysics Data System (ADS)

    Cordiner, Martin

    2016-06-01

    Titan's atmospheric photochemistry results in the production of a wide range of organic molecules, including hydrocarbons, nitriles, aromatics and other complex species of possible pre-biotic relevance. Studies of Titan's atmospheric chemistry thus provide a unique opportunity to explore the origin and evolution of organic matter in primitive (terrestrial) planetary atmospheres. The Atacama Large Millimeter/submillimeter Array (ALMA) is a powerful new facility, well suited to the study of molecular emission from Titan's upper and middle-atmosphere. Results will be presented from our ongoing studies of Titan using ALMA data obtained during the period 2012-2014 [1,2], including detection and mapping of emission from C2H5CN, HNC, HC3N, CH3CN and CH3CCH. In addition, combining data from multiple ALMA Band 6 observations, we obtained high-resolution spectra with unprecedented sensitivity, enabling the first detection of C2H3CN (vinyl cyanide) on Titan, and derived a mean C2H3CN C2H5CN abundance ratio above 300 km of 0.3. Vinyl cyanide has recently been investigated as a possible constituent of (pre-biotic) vesicle membranes in Titan's liquid CH4 oceans [3]. Radiative transfer models and possible chemical formation pathways for the detected molecules will be discussed. ALMA observations provide instantaneous snapshot mapping of Titan's entire Earth-facing hemisphere for gases inaccessible to previous studies, and therefore provide new insights into photochemical production and transport, particularly at higher altitudes. Our maps show spatially resolved peaks in Titan's northern and southern hemispheres, consistent with the molecular distributions found in previous studies at infrared wavelengths by Voyager and Cassini, but high-altitude longitudinal asymmetries in our nitrile data indicate that the mesosphere may be more spatially variable than previously thought.

  1. First year of ALMA site software deployment: where everything comes together

    NASA Astrophysics Data System (ADS)

    González, Víctor; Mora, Matias; Araya, Rodrigo; Arredondo, Diego; Bartsch, Marcelo; Burgos, Pablo; Ibsen, Jorge; Reveco, Johnny; Sáez, Norman; Schemrl, Anton; Sepulveda, Jorge; Shen, Tzu-Chiang; Soto, Rubén; Troncoso, Nicolás; Zambrano, Mauricio; Barriga, Nicolás; Glendenning, Brian; Raffi, Gianni; Kern, Jeff

    2010-07-01

    Starting 2009, the ALMA project initiated one of its most exciting phases within construction: the first antenna from one of the vendors was delivered to the Assembly, Integration and Verification team. With this milestone and the closure of the ALMA Test Facility in New Mexico, the JAO Computing Group in Chile found itself in the front line of the project's software deployment and integration effort. Among the group's main responsibilities are the deployment, configuration and support of the observation systems, in addition to infrastructure administration, all of which needs to be done in close coordination with the development groups in Europe, North America and Japan. Software support has been the primary interaction key with the current users (mainly scientists, operators and hardware engineers), as the software is normally the most visible part of the system. During this first year of work with the production hardware, three consecutive software releases have been deployed and commissioned. Also, the first three antennas have been moved to the Array Operations Site, at 5.000 meters elevation, and the complete end-to-end system has been successfully tested. This paper shares the experience of this 15-people group as part of the construction team at the ALMA site, and working together with Computing IPT, on the achievements and problems overcomed during this period. It explores the excellent results of teamwork, and also some of the troubles that such a complex and geographically distributed project can run into. Finally, it approaches the challenges still to come, with the transition to the ALMA operations plan.

  2. Isotopic Ratios in Nitriles from Submillimeter Spectroscopy Using SMA and ALMA

    NASA Astrophysics Data System (ADS)

    Gurwell, Mark A.; Moreno, Raphael; Vinatier, Sandrine; Lellouch, Emmanuel; Butler, Bryan J.; Moullet, Arielle; Lara, Luisa; Hidayat, Taufiq

    2016-10-01

    We present submillimeter spectroscopic observations of Titan obtained using the Submillimeter Array (SMA) in 2011, and the Atacama Large Millimeter/Submillimeter Array (ALMA) in 2012, some of which have previously been presented but not fully analyzed (1, 2, 3). The SMA observations were obtained at low spatial resolution, providing disk average spectra, but the ALMA observations provide low resolution mapping of Titan (~0.4"-0.6" when Titan was 0.77" surface diameter). We will present detailed radiative transfer analysis of detected spectral lines to derive isotopic ratios in two nitriles: HCN (D/H, 13C/12C, 15N/14N) and HC3N (15N/14N). The analysis makes use of nearly concurrent CIRS temperature profiles as important constraints for the vertical profiles of these species, allowing high precision measurements of the ratios. Finally, we will highlight current and future ALMA observations that will allow monitoring of non-symmetric molecular species in Titan's upper atmosphere from Earth, beyond the end of the Cassini mission.(1) Gurwell et al (2011) EPSC-DPS Joint Meeting 2011, p270. (2) Moreno et al (2014) EPSC 2014 Abstracts, Vol. 9, id. EPSC2014-438. (3) Moreno etal (2014), DPS meeting #46, id.211.19

  3. Spatial Variations of Chemical Abundances in Titan's Atmosphere as Revealed by ALMA

    NASA Astrophysics Data System (ADS)

    Thelen, Alexander E.; Nixon, Conor; Chanover, Nancy J.; Molter, Edward; Serigano, Joseph; Cordiner, Martin; Charnley, Steven B.; Teanby, Nicholas A.; Irwin, Patrick

    2016-10-01

    Complex organic molecules in Titan's atmosphere - formed through the dissociation of N2 and CH4 - exhibit latitudinal variations in abundance as observed by Cassini. Chemical species including hydrocarbons - such as CH3CCH - and nitriles - HCN, HC3N, CH3CN, and C2H5CN - may show spatial abundance variations as a result of atmospheric circulation, photochemical production and subsequent destruction throughout Titan's seasonal cycle. Recent calibration images of Titan taken by the Atacama Large Millimeter/Submillimeter Array (ALMA) with beam sizes of ~0.3'' allow for measurements of rotational transition lines of these species in spatially resolved regions of Titan's disk. We present abundance profiles obtained from public ALMA data taken in 2014, as Titan transitioned into northern summer. Abundance profiles in Titan's lower/middle atmosphere were retrieved by modeling high resolution ALMA spectra using the Non-linear Optimal Estimator for MultivariatE Spectral analySIS (NEMESIS) radiative transfer code. These retrievals were performed using spatial temperature profiles obtained by modeling strong CO lines from datasets taken in similar times with comparable resolution. We compare the abundance variations of chemical species to measurements made using Cassini data. Comparisons of chemical species with strong abundance enhancements over the poles will inform our knowledge of chemical lifetimes in Titan's atmosphere, and allow us to observe the important changes in production and circulation of numerous organic molecules which are attributed to Titan's seasons.

  4. Virtualization in network and servers infrastructure to support dynamic system reconfiguration in ALMA

    NASA Astrophysics Data System (ADS)

    Shen, Tzu-Chiang; Ovando, Nicolás.; Bartsch, Marcelo; Simmond, Max; Vélez, Gastón; Robles, Manuel; Soto, Rubén.; Ibsen, Jorge; Saldias, Christian

    2012-09-01

    ALMA is the first astronomical project being constructed and operated under industrial approach due to the huge amount of elements involved. In order to achieve the maximum through put during the engineering and scientific commissioning phase, several production lines have been established to work in parallel. This decision required modification in the original system architecture in which all the elements are controlled and operated within a unique Standard Test Environment (STE). The advance in the network industry and together with the maturity of virtualization paradigm allows us to provide a solution which can replicate the STE infrastructure without changing their network address definition. This is only possible with Virtual Routing and Forwarding (VRF) and Virtual LAN (VLAN) concepts. The solution allows dynamic reconfiguration of antennas and other hardware across the production lines with minimum time and zero human intervention in the cabling. We also push the virtualization even further, classical rack mount servers are being replaced and consolidated by blade servers. On top of them virtualized server are centrally administrated with VMWare ESX. Hardware costs and system administration effort will be reduced considerably. This mechanism has been established and operated successfully during the last two years. This experience gave us confident to propose a solution to divide the main operation array into subarrays using the same concept which will introduce huge flexibility and efficiency for ALMA operation and eventually may simplify the complexity of ALMA core observing software since there will be no need to deal with subarrays complexity at software level.

  5. Development and testing of Band 10 receivers for the ALMA project

    NASA Astrophysics Data System (ADS)

    Uzawa, Y.; Fujii, Y.; Gonzalez, A.; Kaneko, K.; Kroug, M.; Kojima, T.; Kuroiwa, K.; Miyachi, A.; Saito, S.; Makise, K.; Wang, Z.; Asayama, S.

    2013-11-01

    The production model of a dual polarization heterodyne receiver for the Atacama Large Millimeter/submillimteter Array (ALMA) telescope has been developed to operate in the 787-950 GHz frequency band. The receiver uses two double sideband (DSB) waveguide mixers with Nb/AlOx/Nb tunnel junctions and NbTiN/SiO2/Al microstrip tuning circuits on quartz substrate. A terahertz time domain spectrometer was used to characterize our NbTiN film for the tuning circuit design, which revealed that the complex conductivity of the film is described by the Mattis-Bardeen theory including a finite scattering time of 15 fs and a superconducting gap with a gap ratio 2Δ/kBTC ∼ 4.0. Tens of these receivers (out of the total production number of 73) have been successfully produced, and their performance is well within the stringent ALMA requirements. The best achieved DSB receiver noise temperature is 125 K, corresponding to about 3hf/kB for 4 K operation. One of Band 10 receivers has successfully been installed in the ALMA antenna for a test observation.

  6. Observing the Circumstellar Environment of the Eruptive FUor/EXor Protostar V1647 Ori with ALMA

    NASA Astrophysics Data System (ADS)

    Principe, David; Cieza, Lucas A.; Zhu, Zhaohuan; Tobin, John J.; Prieto, Jose Luis

    2016-01-01

    Fu Ori (FUor) and EXor objects represent a short-lived stage of protostellar evolution characterized by intense mass accretion events which cause extreme variability in the form of outbursts. While it is well demonstrated that these objects exhibit sudden outbursts (ΔV~2-6), the mechanism causing such variability is not well understood. High spatial and spectral resolution observations of the circumstellar environment of these objects are essential to distinguish between different outbursting mechanisms. We present ALMA observations of the FUor/EXor object V1647 Ori as part of an ALMA campaign, which has observed a combined eight FUor and EXor type objects. Deeply embedded in the dark cloud LDN 1630 (L1630), V1647 Ori is one of a few FUor/EXor objects to have been extensively studied at multiple wavelengths before, during and after an outburst. We present preliminary results derived from ALMA 12CO, 13CO, C18O and continuum observations of the circumstellar environment of V1647 Ori. By measuring gas/dust masses and gas kinematics of the circumstellar disk, we investigate the potential mechanisms producing variability in these eruptive protostars during an essential, yet rarely observed, stage of pre-main sequence stellar evolution.

  7. Prototype Implementation of Web and Desktop Applications for ALMA Science Verification Data and the Lessons Learned

    NASA Astrophysics Data System (ADS)

    Eguchi, S.; Kawasaki, W.; Shirasaki, Y.; Komiya, Y.; Kosugi, G.; Ohishi, M.; Mizumoto, Y.

    2013-10-01

    ALMA is estimated to generate TB scale data during only one observation; astronomers need to identify which part of the data they are really interested in. We have been developing new GUI software for this purpose utilizing the VO interface: ALMA Web Quick Look System (ALMAWebQL) and ALMA Desktop Application (Vissage). The former is written in JavaScript and HTML5 generated from Java code by the Google Web Toolkit, and the latter is in pure Java. An essential point of our approach is how to reduce network traffic: we prepare, in advance, “compressed” FITS files of 2x2x1 (horizontal, vertical, and spectral directions, respectively) binning, 2 x 2 x 2 binning, 4 x 4 x 2 binning data, and so on. These files are hidden from users, and Web QL automatically chooses the proper one for each user operation. Through this work, we find that network traffic in our system is still a bottleneck towards TB scale data distribution. Hence we have to develop alternative data containers for much faster data processing. In this paper, we introduce our data analysis systems, and describe what we learned through the development.

  8. ALMA CONTINUUM OBSERVATIONS OF A 30 Myr OLD GASEOUS DEBRIS DISK AROUND HD 21997

    SciTech Connect

    Moór, A.; Ábrahám, P.; Kiss, Cs.; Gabányi, K.; Juhász, A.; Schmalzl, M.; Kóspál, Á.; Apai, D.; Pascucci, I.; Csengeri, T.; Grady, C.; Henning, Th.; Hughes, A. M.

    2013-11-10

    Circumstellar disks around stars older than 10 Myr are expected to be gas-poor. There are, however, two examples of old (30-40 Myr) debris-like disks containing a detectable amount of cold CO gas. Here we present Atacama Large Millimeter/Submillimeter Array (ALMA) and Herschel Space Observatory observations of one of these disks, around HD 21997, and study the distribution and origin of the dust and its connection to the gas. Our ALMA continuum images at 886 μm clearly resolve a broad ring of emission within a diameter of ∼4.''5, adding HD 21997 to the dozen debris disks resolved at (sub)millimeter wavelengths. Modeling the morphology of the ALMA image with a radiative transfer code suggests inner and outer radii of ∼55 and ∼150 AU, and a dust mass of 0.09 M {sub ⊕}. Our data and modeling hints at an extended cold outskirt of the ring. Comparison with the morphology of the CO gas in the disk reveals an inner dust-free hole where gas nevertheless can be detected. Based on dust grain lifetimes, we propose that the dust content of this gaseous disk is of secondary origin and is produced by planetesimals. Since the gas component is probably primordial, HD 21997 is one of the first known examples of a hybrid circumstellar disk, a thus-far little studied late phase of circumstellar disk evolution.

  9. The Alma-Bacon County Story: A Model for Rural America. Committee Print, 92nd Congress, 2nd Session, July 24, 1972.

    ERIC Educational Resources Information Center

    Nipp, Robert E.

    Designed to illustrate the revitalization process of a small rural community via use of the Model Cities Program, this case study of Alma-Bacon County, Georgia traces Alma-Bacon's: (1) historical background; (2) community development beginnings; (3) political development; (4) outstanding problems; and (5) development plans and accomplishments…

  10. ALMA Resolves the Torus of NGC 1068: Continuum and Molecular Line Emission

    NASA Astrophysics Data System (ADS)

    García-Burillo, S.; Combes, F.; Ramos Almeida, C.; Usero, A.; Krips, M.; Alonso-Herrero, A.; Aalto, S.; Casasola, V.; Hunt, L. K.; Martín, S.; Viti, S.; Colina, L.; Costagliola, F.; Eckart, A.; Fuente, A.; Henkel, C.; Márquez, I.; Neri, R.; Schinnerer, E.; Tacconi, L. J.; van der Werf, P. P.

    2016-05-01

    We used the Atacama Large Millimeter Array (ALMA) to map the emission of the CO(6-5) molecular line and the 432 μm continuum emission from the 300 pc sized circumnuclear disk (CND) of the nearby Seyfert 2 galaxy NGC 1068 with a spatial resolution of ˜4 pc. These observations spatially resolve the CND and, for the first time, image the dust emission, the molecular gas distribution, and the kinematics from a 7-10 pc diameter disk that represents the submillimeter counterpart of the putative torus of NGC 1068. We fitted the nuclear spectral energy distribution of the torus using ALMA and near- and mid-infrared (NIR/MIR) data with CLUMPY torus models. The mass and radius of the best-fit solution for the torus are both consistent with the values derived from the ALMA data alone: {M}{{gas}}{{torus}}=(1+/- 0.3)× {10}5 {M}⊙ and R torus = 3.5 ± 0.5 pc. The dynamics of the molecular gas in the torus show strong non-circular motions and enhanced turbulence superposed on a surprisingly slow rotation pattern of the disk. By contrast with the nearly edge-on orientation of the H2O megamaser disk, we found evidence suggesting that the molecular torus is less inclined (i = 34°-66°) at larger radii. The lopsided morphology and complex kinematics of the torus could be the signature of the Papaloizou-Pringle instability, long predicted to likely drive the dynamical evolution of active galactic nuclei tori.

  11. ALMA IMAGING OF MILLIMETER/SUBMILLIMETER CONTINUUM EMISSION IN ORION KL

    SciTech Connect

    Hirota, Tomoya; Honma, Mareki; Kim, Mi Kyoung; Kurono, Yasutaka

    2015-03-10

    We have carried out high-resolution observations with the Atacama Large Millimeter/Submillimeter Array (ALMA) of continuum emission from the Orion Kleinmann–Low (KL) region. We identify 11 compact sources at ALMA band 6 (245 GHz) and band 7 (339 GHz), including the Hot Core, Compact Ridge, SMA1, IRc4, IRc7, and a radio source I (Source I). A spectral energy distribution (SED) of each source is determined by using previous 3 mm continuum emission data. Physical properties such as size, mass, hydrogen number density, and column density are discussed based on the dust graybody SED. Among 11 identified sources, Source I, a massive protostar candidate, is a dominant energy source in Orion KL. We extensively investigate its SED from centimeter to submillimeter wavelengths. The SED of Source I can be fitted with a single power-law index of 1.97, suggesting an optically thick emission. We employ the H{sup −} free–free emission as an opacity source of this optically thick emission. The temperature, density, and mass of the circumstellar disk associated with Source I are constrained by the SED of H{sup −} free–free emission. Still, the fitting result shows a significant deviation from the observed flux densities. Combined with the thermal dust graybody SED to explain excess emission at higher frequency, a smaller power-law index of 1.60 for the H{sup −} free–free emission is obtained in the SED fitting. The power-law index smaller than two would suggest a compact source size or a clumpy structure unresolved with the present study. Future higher resolution observations with ALMA are essential to reveal more detailed spatial structure and physical properties of Source I.

  12. ALMA OBSERVATIONS OF SPT-DISCOVERED, STRONGLY LENSED, DUSTY, STAR-FORMING GALAXIES

    SciTech Connect

    Hezaveh, Y. D.; Marrone, D. P.; Spilker, J. S.; Bothwell, M.; Fassnacht, C. D.; Vieira, J. D.; Aguirre, J. E.; Aird, K. A.; Aravena, M.; De Breuck, C.; Ashby, M. L. N.; Bayliss, M.; Benson, B. A.; Bleem, L. E.; Carlstrom, J. E.; Chang, C. L.; Crawford, T. M.; Crites, A. T.; Brodwin, M.; Chapman, S. C.; and others

    2013-04-20

    We present Atacama Large Millimeter/submillimeter Array (ALMA) 860 {mu}m imaging of four high-redshift (z = 2.8-5.7) dusty sources that were detected using the South Pole Telescope (SPT) at 1.4 mm and are not seen in existing radio to far-infrared catalogs. At 1.''5 resolution, the ALMA data reveal multiple images of each submillimeter source, separated by 1''-3'', consistent with strong lensing by intervening galaxies visible in near-IR imaging of these sources. We describe a gravitational lens modeling procedure that operates on the measured visibilities and incorporates self-calibration-like antenna phase corrections as part of the model optimization, which we use to interpret the source structure. Lens models indicate that SPT0346-52, located at z = 5.7, is one of the most luminous and intensely star-forming sources in the universe with a lensing corrected FIR luminosity of 3.7 Multiplication-Sign 10{sup 13} L{sub Sun} and star formation surface density of 4200 M{sub Sun} yr{sup -1} kpc{sup -2}. We find magnification factors of 5 to 22, with lens Einstein radii of 1.''1-2.''0 and Einstein enclosed masses of 1.6-7.2 Multiplication-Sign 10{sup 11} M{sub Sun }. These observations confirm the lensing origin of these objects, allow us to measure their intrinsic sizes and luminosities, and demonstrate the important role that ALMA will play in the interpretation of lensed submillimeter sources.

  13. The extreme deuteration of formaldehyde toward IRAS 16293-2422 as probed by ALMA

    NASA Astrophysics Data System (ADS)

    Vilhelm Persson, Magnus; van Dishoeck, Ewine; Coutens, Audrey; Jorgensen, Jes K.; Taquet, Vianney; Furuya, Kenji

    2015-08-01

    Formaldehyde (H2CO) is a molecule that forms efficiently both in the gas-phase and on grains at low temperatures. In the solar-type protostar IRAS 16293-2422 formaldehyde has been shown to have a very high degree of deuteration (HDCO/H2CO: 10-15% e.g. van Dishoeck+1995, Loinard+2000, 2001), including the detection of extended doubly deuterated formaldehyde at a level of 3~16% (Ceccarelli et al. 2001). These high levels can only be explained by grain surface reactions in a cold phase. Previous studies have used single-dish telescopes, which pick up emission from both the hot core and the large scale envelope as demonstrated previously for the deuteration of water with ALMA and PdBI data (Persson+2013, 2014, Coutens+2014). This could have a large effect on the derived abundances for the inner envelope. High-angular resolution observations using ALMA and PdBI/NOEMA are needed to properly derive the deuteration of water in the inner envelope (Persson+2013, 2014). In this study we use ALMA observations of IRAS 16293-2422 on formaldehyde. We derive the amount of deuteration for formaldehyde on small scales, and compare it with water and methanol on similar scales. In particular, we check whether the puzzling high D2O/HDO ratio compared with HDO/H2O found by Coutens+2014 also holds for formaldehyde. Multilayer gas-grain models based on laboratory experiments are used to interpret the data (e.g. Taquet+2014).

  14. ALMA OBSERVATIONS OF THE DEBRIS DISK AROUND THE YOUNG SOLAR ANALOG HD 107146

    SciTech Connect

    Ricci, L.; Carpenter, J. M.; Fu, B.; Hughes, A. M.; Corder, S.; Isella, A.

    2015-01-10

    We present the Atacama Large Millimeter/submillimeter Array (ALMA) continuum observations at a wavelength of 1.25 mm of the debris disk surrounding the ∼100 Myr old solar analog HD 107146. The continuum emission extends from about 30 to 150 AU from the central star with a decrease in the surface brightness at intermediate radii. We analyze the ALMA interferometric visibilities using debris disk models with radial profiles for the dust surface density parameterized as (1) a single power law, (2) a single power law with a gap, and (3) a double power law. We find that models with a gap of radial width ∼8 AU at a distance of ∼80 AU from the central star, as well as double power-law models with a dip in the dust surface density at ∼70 AU provide significantly better fits to the ALMA data than single power-law models. We discuss possible scenarios for the origin of the HD 107146 debris disk using models of planetesimal belts in which the formation of Pluto-sized objects trigger disruptive collisions of large bodies, as well as models that consider the interaction of a planetary system with a planetesimal belt and spatial variation of the dust opacity across the disk. If future observations with higher angular resolution and sensitivity confirm the fully depleted gap structure discussed here, a planet with a mass of approximately a few Earth masses in a nearly circular orbit at ∼80 AU from the central star would be a possible explanation for the presence of the gap.

  15. Engineering within the assembly, verification, and integration (AIV) process in ALMA

    NASA Astrophysics Data System (ADS)

    Lopez, Bernhard; McMullin, Joseph P.; Whyborn, Nicholas D.; Duvall, Eugene

    2010-07-01

    The Atacama Large Millimeter/submillimeter Array (ALMA) is a joint project between astronomical organizations in Europe, North America, and East Asia, in collaboration with the Republic of Chile. ALMA will consist of at least 54 twelve-meter antennas and 12 seven-meter antennas operating as an interferometer in the millimeter and sub-millimeter wavelength range. It will be located at an altitude above 5000m in the Chilean Atacama desert. As part of the ALMA construction phase the Assembly, Verification and Integration (AIV) team receives antennas and instrumentation from Integrated Product Teams (IPTs), verifies that the sub-systems perform as expected, performs the assembly and integration of the scientific instrumentation and verifies that functional and performance requirements are met. This paper aims to describe those aspects related to the AIV Engineering team, its role within the 4-station AIV process, the different phases the group underwent, lessons learned and potential space for improvement. AIV Engineering initially focused on the preparation of the necessary site infrastructure for AIV activities, on the purchase of tools and equipment and on the first ALMA system installations. With the first antennas arriving on site the team started to gather experience with AIV Station 1 beacon holography measurements for the assessment of the overall antenna surface quality, and with optical pointing to confirm the antenna pointing and tracking capabilities. With the arrival of the first receiver AIV Station 2 was developed which focuses on the installation of electrical and cryogenic systems and incrementally establishes the full connectivity of the antenna as an observing platform. Further antenna deliveries then allowed to refine the related procedures, develop staff expertise and to transition towards a more routine production process. Stations 3 and 4 deal with verification of the antenna with integrated electronics by the AIV Science Team and is not covered

  16. [Present diet and energy expenditure of young sportsmen-swimmers of Alma-Ata].

    PubMed

    Zhumabaeva, G G; Tkach, N Z; Musabekov, S M; Kerimbekov, B K; Musabekov, S K

    1976-01-01

    From pertinent investigations it follows that the daily food allowances for young swimmers of the sporting-type boarding school in Alma-Ata fully cover their needs for such main ingredients as protein, fats, carbohydrates and conform to the amount of energy expended by them. One should, however, point out some serious qualitative drawbacks in the dietary of the school inmates, such as an insufficient content of vitamins "B2" and "C" in the daily food ration. The data obtained may be of use in formulating an optimal dietary for the young swimmers of the boarding school in question. PMID:136087

  17. Gaps, rings, and non-axisymmetric structures in protoplanetary disks. From simulations to ALMA observations

    NASA Astrophysics Data System (ADS)

    Flock, M.; Ruge, J. P.; Dzyurkevich, N.; Henning, Th.; Klahr, H.; Wolf, S.

    2015-02-01

    Aims: Recent observations by the Atacama Large Millimeter/submillimeter Array (ALMA) of disks around young stars revealed distinct asymmetries in the dust continuum emission. In this work we wish to study axisymmetric and non-axisymmetric structures that are generated by the magneto-rotational instability in the outer regions of protoplanetary disks. We combine the results of state-of-the-art numerical simulations with post-processing radiative transfer (RT) to generate synthetic maps and predictions for ALMA. Methods: We performed non-ideal global 3D magneto-hydrodynamic (MHD) stratified simulations of the dead-zone outer edge using the FARGO MHD code PLUTO. The stellar and disk parameters were taken from a parameterized disk model applied for fitting high-angular resolution multi-wavelength observations of various circumstellar disks. We considered a stellar mass of M∗ = 0.5 M⊙ and a total disk mass of about 0.085 M∗. The 2D initial temperature and density profiles were calculated consistently from a given surface density profile and Monte Carlo radiative transfer. The 2D Ohmic resistivity profile was calculated using a dust chemistry model. We considered two values for the dust-to-gas mass ratio, 10-2 and 10-4, which resulted in two different levels of magnetic coupling. The initial magnetic field was a vertical net flux field. The radiative transfer simulations were performed with the Monte Carlo-based 3D continuum RT code MC3D. The resulting dust reemission provided the basis for the simulation of observations with ALMA. Results: All models quickly turned into a turbulent state. The fiducial model with a dust-to-gas mass ratio of 10-2 developed a large gap followed by a jump in surface density located at the dead-zone outer edge. The jump in density and pressure was strong enough to stop the radial drift of particles at this location. In addition, we observed the generation of vortices by the Rossby wave instability at the jump location close to 60 AU

  18. Dusty Starbursts within a z=3 Large Scale Structure revealed by ALMA

    NASA Astrophysics Data System (ADS)

    Umehata, Hideki

    The role of the large-scale structure is one of the most important theme in studying galaxy formation and evolution. However, it has been still mystery especially at z>2. On the basis of our ALMA 1.1 mm observations in a z ~ 3 protocluster field, it is suggested that submillimeter galaxies (SMGs) preferentially reside in the densest environment at z ~ 3. Furthermore we find a rich cluster of AGN-host SMGs at the core of the protocluster, combining with Chandra X-ray data. Our results indicate the vigorous star-formation and accelerated super massive black hole (SMBH) growth in the node of the cosmic web.

  19. Cross-polarization in quasi-optical receivers: ALMA band 4 and 10

    NASA Astrophysics Data System (ADS)

    Gonzalez, A.; Uzawa, Y.

    2012-09-01

    A careful study about the influence of individual optical components on receiver cross-polarization has been performed. The basic mechanisms of generation of cross-polarization in ellipsoidal mirrors and dielectrics have been reviewed and characterized in terms of higher-order Gaussian beam modes. A simple model considering the phase differences of different Gaussian beam modes is proposed in order to calculate the final system cross-polarization pattern. This model has been successfully used to characterize the total cross-polarization in two cryogenically-cooled receivers for astronomy: ALMA band 4 and band 10.

  20. Monitoring the thermal structure and minor species of Venus mesosphere with ALMA submm observations

    NASA Astrophysics Data System (ADS)

    Piccialli, Arianna; Moreno, Raphael; Encrenaz, Therese A.; Fouchet, Thierry; Lellouch, Emmanuel; Moullet, Arielle; Widemann, Thomas

    2016-10-01

    Submillimeter observations obtained with the Atacama Large Millimeter Array (ALMA) allowed to monitoring the temporal evolution of temperature, sulfur species and water in the upper atmosphere of Venus. We observed the upper atmosphere of Venus with ALMA on November 14, 15, 26 and 27, 2011 during the first ALMA Early Science observation cycle. These observations targeted CO, SO, HDO and SO2 transitions around 345 GHz during four sequences of 30 minutes each. The disk of Venus was about 11" with an illumination factor of 90%, so that mostly the dayside of the planet was mapped.Thanks to the imaging capabilities of ALMA, we could obtain instantaneous maps of temperature, SO and HDO for the four days of observations. Assuming a nominal dayside CO abundance profile adapted from Clancy et al. 2012, we retrieved vertical temperature profiles between 60-100 km of altitude over the entire disk as a function of latitude and local time for the four days of observation. Temperature profiles were later used to derive the abundances of minor species (SO and HDO) in each pixel of the disk in order to study their spatial and temporal variability. Moreover, we plan to analyze the SO2 disk-averaged spectra to study its temporal variability.Temperature profiles show at all latitudes and local times a similar behavior with a constant decrease of temperature up to an altitude of about 80-100 km, depending on the local time, followed by a constant increase of temperature. Up to about 90 km temperatures increase from the morning side towards the evening terminator, this trend is inverted above 90 km. The thermal structure does not show strong temporal variations from one day to another. An exception is the thermal structure of the November 27: compared to the first day of observation, temperatures change of more than 15 K.SO exhibits a strong spatial and temporal variability with a mixing ratio ranging from 0 to 15 ppb. It presents also a clear cutoff around 89 km. HDO is detected

  1. Report on the ESO Workshop ''mm-wave VLBI with ALMA and Radio Telescopes around the World''

    NASA Astrophysics Data System (ADS)

    Falcke, H.; Laing, R.; Testi, L.; Zensus, A.

    2012-09-01

    Very long baseline interferometry at millimetre/submillimetre wavelengths (mm-VLBI) offers the highest achievable spatial resolution at any wavelength in astronomy and the inclusion of ALMA into a global network will bring unprecedented sensitivity. The workshop on mm-VLBI reviewed the broad range of science topics, from imaging the event horizon of the black hole at the centre of the Galaxy, through masers in the Milky Way and distant galaxies to jets in radio galaxies. Plans were laid to develop a science case and a European organisation to promote mm-VLBI including ALMA.

  2. The New ALMA Prototype 12 M Telescope of the Arizona Radio Observatory

    NASA Astrophysics Data System (ADS)

    Ziurys, Lucy M.; Folkers, Thomas W.; Emerson, Nicholas J.; Freund, Robert; Lauria, Eugene F.; Forbes, David; Reiland, George P.; McColl, Martin

    2016-06-01

    The Arizona Radio Observatory (ARO) recently acquired the European 12 m prototype antenna of the Atacama Large Millimeter Array (ALMA) project from the European Southern Observatory (ESO). The antenna was located at the Very Large Array (VLA) site near Socorro, New Mexico. In November 2013, the 97 ton antenna was transported to Kitt Peak, Arizona in two major parts: the 40 ft. reflector and the base/receiver cabin. The antenna, which replaced the former NRAO 12 m telescope, was reassembled in the dome at Kitt Peak. Recommissioning began in January 2014, and scientific observations commenced in early 2015. The instrument is now fully operational with a measured surface accuracy of 53 microns, rms, and a pointing accuracy of 2 arc seconds. Further antenna improvements are in progress. The new 12 m currently supports a dual polarization, 3 mm receiver (84-116 GHz) with ALMA Band 3 sideband-separating mixers. A multiband receiver also covering the 4 mm (67 – 90 GHz), 2 mm (130-180 GHz) and 1 mm (210-280 GHz) regions with dual polarization, sideband-separating mixers is currently under construction. A new digital backend, the ARO Wideband Spectrometer (AROWS: 4 x 4 GHz total bandwidth ), is also in the development stage.

  3. Kennicutt-Schmidt Law in the Central Region of NGC 4321 as Seen by ALMA

    NASA Astrophysics Data System (ADS)

    Azeez, Jazeel H.; Hwang, C.-Y.; Abidin, Zamri Z.; Ibrahim, Zainol A.

    2016-06-01

    We present the Atacama Large Millimeter/Sub-millimeter Array (ALMA) cycle-0 science verification data of the CO(1–0) line emission in the central region of NGC 4321 (also known as M100) at the distance of 17.1 Mpc and VLA, L-band data of HI of the same galaxy. We have drawn the center area of M100 in the 12CO(J = 1–0) line with the resolution of (3.87″ × 2.53″) as viewed by ALMA, along with HI and Spitzer 8 and 3.6 μm data. The relationship between the surface density of molecular gas mass ∑H2 and that of star formation rate ∑SFR has been investigated, in addition to the relationship between the surface density of the neutral atomic hydrogen mass and that of ∑SFR (Kennicutt–Schmidt law) in this galaxy with a high spatial resolution. The results indicate that a significant correlation exists between the SFR surface density and the molecular gas mass density in the ~2 kpc region. The power-law index has been determined for three regions: center, upper and lower arms. The value of this index in the center region is 1.13, which follows the traditional (K-S) law and indicates that the molecular gas is affected by star formation.

  4. RESOLVED IMAGES OF THE PROTOPLANETARY DISK AROUND HD 100546 WITH ALMA

    SciTech Connect

    Pineda, Jaime E.; Quanz, Sascha P.; Meru, Farzana; Meyer, Michael R.; Avenhaus, Henning; Mulders, Gijs D.; Panić, Olja

    2014-06-20

    The disk around the Herbig Ae/Be star HD 100546 has been extensively studied and it is one of the systems for which there are observational indications of ongoing and/or recent planet formation. However, up until now, no resolved image of the millimeter dust emission or the gas has been published. We present the first resolved images of the disk around HD 100546 obtained in Band 7 with the ALMA observatory. The CO (3-2) image reveals a gas disk that extends out to 350 au radius at the 3σ level. Surprisingly, the 870 μm dust continuum emission is compact (radius <60 au) and asymmetric. The dust emission is well matched by a truncated disk with an outer radius of ≈50 au. The lack of millimeter-sized particles outside 60 au is consistent with radial drift of particles of this size. The protoplanet candidate, identified in previous high-contrast NACO/VLT L' observations, could be related to the sharp outer edge of the millimeter-sized particles. Future higher angular resolution ALMA observations are needed to determine the detailed properties of the millimeter emission and the gas kinematics in the inner region (<2''). Such observations could also reveal the presence of a planet through the detection of circumplanetary disk material.

  5. FAINT END OF 1.3 mm NUMBER COUNTS REVEALED BY ALMA

    SciTech Connect

    Hatsukade, Bunyo; Ohta, Kouji; Seko, Akifumi; Yabe, Kiyoto; Akiyama, Masayuki

    2013-06-01

    We present the faint end of number counts at 1.3 mm (238 GHz) obtained with the Atacama Large Millimeter/submillimeter Array (ALMA). Band 6 observations were carried out targeting 20 star-forming galaxies at z ∼ 1.4 in the Subaru/XMM-Newton Deep Survey field. In the observations, we serendipitously detect 15 sources (≥3.8σ, S{sub 1.3} {sub mm} = 0.15-0.61 mJy) other than the targeted sources. We create number counts by using these ''sub-mJy sources'', which probe the faintest flux range among surveys at millimeter wavelengths. The number counts are consistent with (flux-scaled) number counts at 850 μm and 870 μm obtained with gravitational lensing clusters. The ALMA number counts agree well with model predictions, which suggest that these sub-mJy populations are more like ''normal'' star-forming galaxies than ''classical'' submillimeter galaxies with intense star-forming activity. In this flux range, ∼80% of the extragalactic background light at 1.3 mm is resolved into individual sources.

  6. Development of the control system for the 40m OAN radiotelescope with the Alma Common Software

    NASA Astrophysics Data System (ADS)

    de Vicente, P.; Bolaño, R.; Barbas, L.

    2006-07-01

    The Observatorio Astronómico Nacional (OAN) is building a 40m radiotelescope in its facilities in Yebes (Spain) which will be delivered in summer 2006. The radiotelescope is an instrument composed of antenna, receivers, backends, and auxiliary equipment connected through a Local Area Network (LAN). The control system has to deal with a distributed environment which needs to be remotely controlled and monitored from external heterogeneous users (astronomers and engineers) and requires multiple processes simultaneously working and being synchronized. We have chosen the Alma Common Software (ACS) framework for the development of the control system. ACS provides an implementation of the component/container paradigm via Common Object Request Broker Architecture (CORBA) and also provides general purpose utility libraries, hiding the complexity of CORBA to the developer. ACS is supported by the European Southern Observatory (ESO) and the National Radioastronomy Observatory (NRAO) for the Atacama Large Millimeter Array (ALMA) with a lifetime similar to our radiotelescope. This is an important guarantee for the OAN with a very reduced software team. We present an overview of the planned software architecture of the radiotelescope and the current status of the development of the components.

  7. Kennicutt-Schmidt Law in the Central Region of NGC 4321 as Seen by ALMA.

    PubMed

    Azeez, Jazeel H; Hwang, C-Y; Abidin, Zamri Z; Ibrahim, Zainol A

    2016-01-01

    We present the Atacama Large Millimeter/Sub-millimeter Array (ALMA) cycle-0 science verification data of the CO(1-0) line emission in the central region of NGC 4321 (also known as M100) at the distance of 17.1 Mpc and VLA, L-band data of HI of the same galaxy. We have drawn the center area of M100 in the (12)CO(J = 1-0) line with the resolution of (3.87″ × 2.53″) as viewed by ALMA, along with HI and Spitzer 8 and 3.6 μm data. The relationship between the surface density of molecular gas mass ∑H2 and that of star formation rate ∑SFR has been investigated, in addition to the relationship between the surface density of the neutral atomic hydrogen mass and that of ∑SFR (Kennicutt-Schmidt law) in this galaxy with a high spatial resolution. The results indicate that a significant correlation exists between the SFR surface density and the molecular gas mass density in the ~2 kpc region. The power-law index has been determined for three regions: center, upper and lower arms. The value of this index in the center region is 1.13, which follows the traditional (K-S) law and indicates that the molecular gas is affected by star formation. PMID:27247251

  8. Millimeter Emission Structure in the First ALMA Image of the AU Mic Debris Disk

    NASA Astrophysics Data System (ADS)

    MacGregor, Meredith A.; Wilner, David J.; Rosenfeld, Katherine A.; Andrews, Sean M.; Matthews, Brenda; Hughes, A. Meredith; Booth, Mark; Chiang, Eugene; Graham, James R.; Kalas, Paul; Kennedy, Grant; Sibthorpe, Bruce

    2013-01-01

    We present 1.3 mm ALMA Cycle 0 observations of the edge-on debris disk around the nearby, ~10 Myr old, M-type star AU Mic. These observations obtain 0.''6 (6 AU) resolution and reveal two distinct emission components: (1) the previously known dust belt that extends to a radius of 40 AU and (2) a newly recognized central peak that remains unresolved. The cold dust belt of mass ~1 M Moon is resolved in the radial direction with a rising emission profile that peaks sharply at the location of the outer edge of the "birth ring" of planetesimals hypothesized to explain the midplane scattered light gradients. No significant asymmetries are discerned in the structure or position of this dust belt. The central peak identified in the ALMA image is ~6 times brighter than the stellar photosphere, which indicates an additional emission process in the inner regions of the system. Emission from a stellar corona or activity may contribute, but the observations show no signs of temporal variations characteristic of radio-wave flares. We suggest that this central component may be dominated by dust emission from an inner planetesimal belt of mass ~0.01 M Moon, consistent with a lack of emission shortward of 25 μm and a location lsim3 AU from the star. Future millimeter observations can test this assertion, as an inner dust belt should be readily separated from the central star at higher angular resolution.

  9. ALMA and PKS 1830-211: the Molecular Absorption and the Background Blazar

    NASA Astrophysics Data System (ADS)

    Muller, S.; PKS1830 Team

    2015-12-01

    The line of sight to the lensed blazar PKS1830-211 intercepts the disk of a foreground spiral galaxy at z=0.89, yielding absorption detected in 40+ molecular species. These molecules can be used as cosmological probes at a look-back time of more than half the present age of the Universe. We can determine their excitation and measure the temperature of the cosmic microwave background, compare their kinematics and set constraints on the variations of the fundamental constants, measure the isotopic ratios from different isotopologues and investigate the elemental enrichment from stellar processes, and, of course, investigate the chemistry in the disk of the absorber. Besides, we obtained ALMA data observed serendipitously at the time of a strong gamma-ray flare of the background blazar, allowing us to investigate its submm activity and the submm to gamma-ray connection. Last we present the first ALMA polarimetry results, with the highest Faraday rotation ever measured, revealing a strong magnetic field at the base of the jet in PKS 1830-211. In short, one target, but many and diverse science results !

  10. SXDF-ALMA 2-arcmin2 deep survey: 1.1-mm number counts

    NASA Astrophysics Data System (ADS)

    Hatsukade, Bunyo; Kohno, Kotaro; Umehata, Hideki; Aretxaga, Itziar; Caputi, Karina I.; Dunlop, James S.; Ikarashi, Soh; Iono, Daisuke; Ivison, Rob J.; Lee, Minju; Makiya, Ryu; Matsuda, Yuichi; Motohara, Kentaro; Nakanishi, Kouichiro; Ohta, Kouji; Tadaki, Ken-ich; Tamura, Yoichi; Wang, Wei-Hao; Wilson, Grant W.; Yamaguchi, Yuki; Yun, Min S.

    2016-06-01

    We report 1.1-mm number counts revealed with the Atacama Large Millimeter/submillimeter Array (ALMA) in the Subaru/XMM-Newton Deep Survey Field (SXDF). The advent of ALMA enables us to reveal millimeter-wavelength number counts down to the faint end without source confusion. However, previous studies are based on the ensemble of serendipitously detected sources in fields originally targeting different sources and could be biased due to the clustering of sources around the targets. We derive number counts in the flux range of 0.2-2 mJy by using 23 (≥4σ) sources detected in a continuous 2.0-arcmin2 area of the SXDF. The number counts are consistent with previous results within errors, suggesting that the counts derived from serendipitously detected sources are not significantly biased, although there could be field-to-field variation due to the small survey area. By using the best-fitting function of the number counts, we find that ˜40% of the extragalactic background light at 1.1 mm is resolved at S1.1mm > 0.2 mJy.

  11. Interaction design challenges and solutions for ALMA operations monitoring and control

    NASA Astrophysics Data System (ADS)

    Pietriga, Emmanuel; Cubaud, Pierre; Schwarz, Joseph; Primet, Romain; Schilling, Marcus; Barkats, Denis; Barrios, Emilio; Vila Vilaro, Baltasar

    2012-09-01

    The ALMA radio-telescope, currently under construction in northern Chile, is a very advanced instrument that presents numerous challenges. From a software perspective, one critical issue is the design of graphical user interfaces for operations monitoring and control that scale to the complexity of the system and to the massive amounts of data users are faced with. Early experience operating the telescope with only a few antennas has shown that conventional user interface technologies are not adequate in this context. They consume too much screen real-estate, require many unnecessary interactions to access relevant information, and fail to provide operators and astronomers with a clear mental map of the instrument. They increase extraneous cognitive load, impeding tasks that call for quick diagnosis and action. To address this challenge, the ALMA software division adopted a user-centered design approach. For the last two years, astronomers, operators, software engineers and human-computer interaction researchers have been involved in participatory design workshops, with the aim of designing better user interfaces based on state-of-the-art visualization techniques. This paper describes the process that led to the development of those interface components and to a proposal for the science and operations console setup: brainstorming sessions, rapid prototyping, joint implementation work involving software engineers and human-computer interaction researchers, feedback collection from a broader range of users, further iterations and testing.

  12. Remote detection and mapping of organic molecules in Titan's atmosphere using ALMA

    NASA Astrophysics Data System (ADS)

    Cordiner, Martin; Nixon, Conor A.; Charnley, Steven B.; Palmer, Maureen; Mumma, Michael J.; Molter, Edward; Teanby, Nicholas; Irwin, Patrick GJ; Kisiel, Zbigniew; Serigano, Joseph

    2016-06-01

    Titan is the largest moon of Saturn, with a thick (1.45 bar) atmosphere composed primarily of molecular nitrogen and methane. Atmospheric photochemistry results in the production of a wide range of complex organic molecules, including hydrocarbons, nitriles, aromatics and species of possible pre-biotic relevance. Studies of Titan's atmospheric chemistry thus provide a unique opportunity to explore the origin and evolution of complex organic matter in a primitive (terrestrial) planetary atmosphere. Underpinned by laboratory measurements, remote and in-situ observations of hydrocarbons, nitriles and oxygen-bearing species provide important new insights in this regard. The Atacama Large Millimeter/submillimeter Array (ALMA) is a powerful new facility, well suited to the study of molecular emission from Titan's upper and middle-atmosphere. This presentation will focus on results from our ongoing studies of Titan using ALMA during the period 2012-2014, including detection and mapping of rotational emission lines from molecules including HNC, CO, HC3N, CH3CN, C2H3CN and C2H5CN, as well minor isotopologues. Possible chemical formation pathways for these species will be discussed, and the the scope for improved understanding of non-aqueous organic chemistry through laboratory experiments and atmospheric/liquid-phase simulations under Titan-like conditions will be examined.

  13. ALMA Reveals a Galaxy-Scale Fountain of Cold Molecular Gas Pumped by a Black Hole

    NASA Astrophysics Data System (ADS)

    Tremblay, Grant

    2016-01-01

    A new ALMA observation of the cool core brightest cluster galaxy in Abell 2597 reveals that a supermassive black hole can act much like a mechanical pump in a water fountain, driving a convective flow of molecular gas that drains into the black hole accretion reservoir, only to be pushed outward again in a jet-driven outflow that then rains back toward the galaxy center from which it came. The ALMA data reveal "shadows" cast by giant molecular clouds falling on ballistic trajectories towards the black hole in the innermost 500 parsecs of the galaxy, manifesting as deep redshifted continuum absorption features. The black hole accretion reservoir, fueled by these infalling cold clouds, powers an AGN that drives a jet-driven molecular outflow in the form of a 10 kpc-scale, billion solar mass expanding molecular bubble or plume. The molecular shell is permeated with young stars, perhaps triggered in situ by the jet. Buoyant X-ray cavities excavated by the propagating radio source may further uplift the molecular filaments, which are observed to fall inward toward the center of the galaxy from which they came, presumably keeping the fountain long-lived. The results show that cold molecular gas can couple to black hole growth via both feedback and feeding, in alignment with "cold chaotic accretion" models for the regulation of star formation in galaxies.

  14. ALMA OBSERVATIONS OF THE OUTFLOW FROM SOURCE I IN THE ORION-KL REGION

    SciTech Connect

    Zapata, Luis A.; Rodriguez, Luis F.; Loinard, Laurent; Schmid-Burgk, Johannes; Menten, Karl M.; Curiel, Salvador

    2012-07-20

    In this Letter, we present sensitive millimeter SiO (J = 5-4; {nu} = 0) line observations of the outflow arising from the enigmatic object Orion Source I made with the Atacama Large Millimeter/Submillimeter Array (ALMA). The observations reveal that at scales of a few thousand AU, the outflow has a marked 'butterfly' morphology along a northeast-southwest axis. However, contrary to what is found in the SiO and H{sub 2}O maser observations at scales of tens of AU, the blueshifted radial velocities of the moving gas are found to the northwest, while the redshifted velocities are in the southeast. The ALMA observations are complemented with SiO (J = 8-7; {nu} = 0) maps (with a similar spatial resolution) obtained with the Submillimeter Array. These observations also show a similar morphology and velocity structure in this outflow. We discuss some possibilities to explain these differences at small and large scales across the flow.

  15. MILLIMETER EMISSION STRUCTURE IN THE FIRST ALMA IMAGE OF THE AU Mic DEBRIS DISK

    SciTech Connect

    MacGregor, Meredith A.; Wilner, David J.; Rosenfeld, Katherine A.; Andrews, Sean M.; Matthews, Brenda; Booth, Mark; Hughes, A. Meredith; Chiang, Eugene; Graham, James R.; Kalas, Paul; Kennedy, Grant; Sibthorpe, Bruce

    2013-01-10

    We present 1.3 mm ALMA Cycle 0 observations of the edge-on debris disk around the nearby, {approx}10 Myr old, M-type star AU Mic. These observations obtain 0.''6 (6 AU) resolution and reveal two distinct emission components: (1) the previously known dust belt that extends to a radius of 40 AU and (2) a newly recognized central peak that remains unresolved. The cold dust belt of mass {approx}1 M{sub Moon} is resolved in the radial direction with a rising emission profile that peaks sharply at the location of the outer edge of the 'birth ring' of planetesimals hypothesized to explain the midplane scattered light gradients. No significant asymmetries are discerned in the structure or position of this dust belt. The central peak identified in the ALMA image is {approx}6 times brighter than the stellar photosphere, which indicates an additional emission process in the inner regions of the system. Emission from a stellar corona or activity may contribute, but the observations show no signs of temporal variations characteristic of radio-wave flares. We suggest that this central component may be dominated by dust emission from an inner planetesimal belt of mass {approx}0.01 M{sub Moon}, consistent with a lack of emission shortward of 25 {mu}m and a location {approx}<3 AU from the star. Future millimeter observations can test this assertion, as an inner dust belt should be readily separated from the central star at higher angular resolution.

  16. ALMA resolves extended star formation in high-z AGN host galaxies

    NASA Astrophysics Data System (ADS)

    Harrison, C. M.; Simpson, J. M.; Stanley, F.; Alexander, D. M.; Daddi, E.; Mullaney, J. R.; Pannella, M.; Rosario, D. J.; Smail, Ian

    2016-03-01

    We present high-resolution (0.3 arcsec) Atacama Large Millimeter Array (ALMA) 870 μm imaging of five z ≈ 1.5-4.5 X-ray detected AGN (with luminosities of L2-8keV > 1042 erg s-1). These data provide a ≳20 times improvement in spatial resolution over single-dish rest-frame far-infrared (FIR) measurements. The sub-millimetre emission is extended on scales of FWHM ≈ 0.2 arcsec-0.5 arcsec, corresponding to physical sizes of 1-3 kpc (median value of 1.8 kpc). These sizes are comparable to the majority of z=1-5 sub-millimetre galaxies (SMGs) with equivalent ALMA measurements. In combination with spectral energy distribution analyses, we attribute this rest-frame FIR emission to dust heated by star formation. The implied star-formation rate surface densities are ≈20-200 M⊙ yr-1 kpc-2, which are consistent with SMGs of comparable FIR luminosities (i.e. LIR ≈ [1-5] × 1012 L⊙). Although limited by a small sample of AGN, which all have high-FIR luminosities, our study suggests that the kpc-scale spatial distribution and surface density of star formation in high-redshift star-forming galaxies is the same irrespective of the presence of X-ray detected AGN.

  17. ALMA Science Verification Data: Millimeter Continuum Polarimetry of the Bright Radio Quasar 3C 286

    NASA Astrophysics Data System (ADS)

    Nagai, H.; Nakanishi, K.; Paladino, R.; Hull, C. L. H.; Cortes, P.; Moellenbrock, G.; Fomalont, E.; Asada, K.; Hada, K.

    2016-06-01

    We present full-polarization observations of the compact, steep-spectrum radio quasar 3C 286 made with the Atacama Large Millimeter and Submillimeter Array (ALMA) at 1.3 mm. These are the first full-polarization ALMA observations, which were obtained in the framework of Science Verification. A bright core and a south-west component are detected in the total intensity image, similar to previous centimeter images. Polarized emission is also detected toward both components. The fractional polarization of the core is about 17%; this is higher than the fractional polarization at centimeter wavelengths, suggesting that the magnetic field is even more ordered in the millimeter radio core than it is further downstream in the jet. The observed polarization position angle (or electric vector position angle (EVPA)) in the core is ˜39◦, which confirms the trend that the EVPA slowly increases from centimeter to millimeter wavelengths. With the aid of multi-frequency VLBI observations, we argue that this EVPA change is associated with the frequency-dependent core position. We also report a serendipitous detection of a sub-mJy source in the field of view, which is likely to be a submillimeter galaxy.

  18. Kennicutt-Schmidt Law in the Central Region of NGC 4321 as Seen by ALMA

    PubMed Central

    Azeez, Jazeel H.; Hwang, C.-Y.; Abidin, Zamri Z.; Ibrahim, Zainol A.

    2016-01-01

    We present the Atacama Large Millimeter/Sub-millimeter Array (ALMA) cycle-0 science verification data of the CO(1–0) line emission in the central region of NGC 4321 (also known as M100) at the distance of 17.1 Mpc and VLA, L-band data of HI of the same galaxy. We have drawn the center area of M100 in the 12CO(J = 1–0) line with the resolution of (3.87″ × 2.53″) as viewed by ALMA, along with HI and Spitzer 8 and 3.6 μm data. The relationship between the surface density of molecular gas mass ∑H2 and that of star formation rate ∑SFR has been investigated, in addition to the relationship between the surface density of the neutral atomic hydrogen mass and that of ∑SFR (Kennicutt–Schmidt law) in this galaxy with a high spatial resolution. The results indicate that a significant correlation exists between the SFR surface density and the molecular gas mass density in the ~2 kpc region. The power-law index has been determined for three regions: center, upper and lower arms. The value of this index in the center region is 1.13, which follows the traditional (K-S) law and indicates that the molecular gas is affected by star formation. PMID:27247251

  19. ALMA observations of a misaligned binary protoplanetary disk system in Orion

    SciTech Connect

    Williams, Jonathan P.; Mann, Rita K.; Francesco, James Di; Johnstone, Doug; Matthews, Brenda; Andrews, Sean M.; Ricci, Luca; Hughes, A. Meredith; Bally, John

    2014-12-01

    We present Atacama Large Millimeter/Submillimeter Array (ALMA) observations of a wide binary system in Orion, with projected separation 440 AU, in which we detect submillimeter emission from the protoplanetary disks around each star. Both disks appear moderately massive and have strong line emission in CO 3-2, HCO{sup +} 4-3, and HCN 3-2. In addition, CS 7-6 is detected in one disk. The line-to-continuum ratios are similar for the two disks in each of the lines. From the resolved velocity gradients across each disk, we constrain the masses of the central stars, and show consistency with optical-infrared spectroscopy, both indicative of a high mass ratio ∼9. The small difference between the systemic velocities indicates that the binary orbital plane is close to face-on. The angle between the projected disk rotation axes is very high, ∼72°, showing that the system did not form from a single massive disk or a rigidly rotating cloud core. This finding, which adds to related evidence from disk geometries in other systems, protostellar outflows, stellar rotation, and similar recent ALMA results, demonstrates that turbulence or dynamical interactions act on small scales well below that of molecular cores during the early stages of star formation.

  20. The New ALMA Prototype 12 M Telescope of the Arizona Radio Observatory

    NASA Astrophysics Data System (ADS)

    Ziurys, Lucy M.; Folkers, Thomas W.; Emerson, Nicholas J.; Freund, Robert; Lauria, Eugene F.; Forbes, David; Reiland, George P.; McColl, Martin

    2016-06-01

    The Arizona Radio Observatory (ARO) recently acquired the European 12 m prototype antenna of the Atacama Large Millimeter Array (ALMA) project from the European Southern Observatory (ESO). The antenna was located at the Very Large Array (VLA) site near Socorro, New Mexico. In November 2013, the 97 ton antenna was transported to Kitt Peak, Arizona in two major parts: the 40 ft. reflector and the base/receiver cabin. The antenna, which replaced the former NRAO 12 m telescope, was reassembled in the dome at Kitt Peak. Recommissioning began in January 2014, and scientific observations commenced in early 2015. The instrument is now fully operational with a measured surface accuracy of 53 microns, rms, and a pointing accuracy of 2 arc seconds. Further antenna improvements are in progress. The new 12 m currently supports a dual polarization, 3 mm receiver (84-116 GHz) with ALMA Band 3 sideband-separating mixers. A multiband receiver also covering the 4 mm (67 - 90 GHz), 2 mm (130-180 GHz) and 1 mm (210-280 GHz) regions with dual polarization, sideband-separating mixers is currently under construction. A new digital backend, the ARO Wideband Spectrometer (AROWS: 4 x 4 GHz total bandwidth ), is also in the development stage.

  1. ALMA WILL DETERMINE THE SPECTROSCOPIC REDSHIFT z > 8 WITH FIR [O III] EMISSION LINES

    SciTech Connect

    Inoue, A. K.; Shimizu, I.; Tamura, Y.; Matsuo, H.; Okamoto, T.; Yoshida, N.

    2014-01-10

    We investigate the potential use of nebular emission lines in the rest-frame far-infrared (FIR) for determining spectroscopic redshift of z > 8 galaxies with the Atacama Large Millimeter/submillimeter Array (ALMA). After making a line emissivity model as a function of metallicity, especially for the [O III] 88 μm line which is likely to be the strongest FIR line from H II regions, we predict the line fluxes from high-z galaxies based on a cosmological hydrodynamics simulation of galaxy formation. Since the metallicity of galaxies reaches at ∼0.2 Z {sub ☉} even at z > 8 in our simulation, we expect the [O III] 88 μm line as strong as 1.3 mJy for 27 AB objects, which is detectable at a high significance by <1 hr integration with ALMA. Therefore, the [O III] 88 μm line would be the best tool to confirm the spectroscopic redshifts beyond z = 8.

  2. Kennicutt-Schmidt Law in the Central Region of NGC 4321 as Seen by ALMA.

    PubMed

    Azeez, Jazeel H; Hwang, C-Y; Abidin, Zamri Z; Ibrahim, Zainol A

    2016-01-01

    We present the Atacama Large Millimeter/Sub-millimeter Array (ALMA) cycle-0 science verification data of the CO(1-0) line emission in the central region of NGC 4321 (also known as M100) at the distance of 17.1 Mpc and VLA, L-band data of HI of the same galaxy. We have drawn the center area of M100 in the (12)CO(J = 1-0) line with the resolution of (3.87″ × 2.53″) as viewed by ALMA, along with HI and Spitzer 8 and 3.6 μm data. The relationship between the surface density of molecular gas mass ∑H2 and that of star formation rate ∑SFR has been investigated, in addition to the relationship between the surface density of the neutral atomic hydrogen mass and that of ∑SFR (Kennicutt-Schmidt law) in this galaxy with a high spatial resolution. The results indicate that a significant correlation exists between the SFR surface density and the molecular gas mass density in the ~2 kpc region. The power-law index has been determined for three regions: center, upper and lower arms. The value of this index in the center region is 1.13, which follows the traditional (K-S) law and indicates that the molecular gas is affected by star formation.

  3. Results of reconnaissance for radioactive minerals in parts of the Alma district, Park County, Colorado

    USGS Publications Warehouse

    Pierson, Charles Thomas; Singewald, Quentin Dreyer

    1953-01-01

    Pitchblende was discovered in July 1951 in the Alma mining district, Park County, Colo., by the U. S. Geological Survey acting on behalf of the U. S. Atomic Energy Commission. The pitchblende is associated with Tertiary veins of three different geologic environments: (1) veins in pre-Cambrian rocks, (2) the London vein system in the footwall block of the London fault, and (3) veins in a mineralized area east of the Cooper Gulch fault. Pitchblende is probably not associated with silver-lead replacement deposits in dolomite. Secondary uranium minerals, as yet undetermined, are associated with pitchblende on two London vein system mine dumps and occur in oxidized vein material from dumps of mines in the other environments. Although none of the known occurrences is of commercial importance, the Alma district is considered a moderately favorable area in which to prospect for uranium ore because 24 of the 43 localities examined show anomalous radioactivity; samples from anomalously radioactive localities, which include mine dumps and some underground workings, have uranium contents ranging from 0.001 to 1.66 percent.

  4. The Space Infrared Interferometric Telescope (SPIRIT) and its Complementarity to ALMA

    NASA Technical Reports Server (NTRS)

    Leisawitz, Dave

    2007-01-01

    We report results of a pre-Formulation Phase study of SPIRIT, a candidate NASA Origins Probe mission. SPIRIT is a spatial and spectral interferometer with an operating wavelength range 25 - 400 microns. SPIRIT will provide sub-arcsecond resolution images and spectra with resolution R = 3000 in a 1 arcmin field of view to accomplish three primary scientific objectives: (1) Learn how planetary systems form from protostellar disks, and how they acquire their chemical organization; (2) Characterize the family of extrasolar planetary systems by imaging the structure in debris disks to understand how and where planets of different types form; and (3) Learn how high-redshift galaxies formed and merged to form the present-day population of galaxies. In each of these science domains, SPIRIT will yield information complementary to that obtainable with the James Webb Space Telescope (JWST)and the Atacama Large Millimeter Array (ALMA), and all three observatories could operate contemporaneously. Here we shall emphasize the SPIRIT science goals (1) and (2) and the mission's complementarity with ALMA.

  5. ALMA imaging of SDP.81 - II. A pixelated reconstruction of the CO emission lines

    NASA Astrophysics Data System (ADS)

    Rybak, M.; Vegetti, S.; McKean, J. P.; Andreani, P.; White, S. D. M.

    2015-10-01

    We present a sub-100 pc-scale analysis of the CO molecular gas emission and kinematics of the gravitational lens system SDP.81 at redshift 3.042 using Atacama Large Millimetre/submillimetre Array (ALMA) science verification data and a visibility-plane lens reconstruction technique. We find clear evidence for an excitation-dependent structure in the unlensed molecular gas distribution, with emission in CO (5-4) being significantly more diffuse and structured than in CO (8-7). The intrinsic line luminosity ratio is r8-7/5-4 = 0.30 ± 0.04, which is consistent with other low-excitation starbursts at z ˜ 3. An analysis of the velocity fields shows evidence for a star-forming disc with multiple velocity components that is consistent with a merger/post-coalescence merger scenario, and a dynamical mass of M(<1.56 kpc) = 1.6 ± 0.6 × 1010 M⊙. Source reconstructions from ALMA and the Hubble Space Telescope show that the stellar component is offset from the molecular gas and dust components. Together with Karl G. Jansky Very Large Array CO (1-0) data, they provide corroborative evidence for a complex ˜2 kpc-scale starburst that is embedded within a larger ˜15 kpc structure.

  6. ON THE NATURE OF THE TERTIARY COMPANION TO FW TAU: ALMA CO OBSERVATIONS AND SED MODELING

    SciTech Connect

    Caceres, Claudio; Hardy, Adam; Schreiber, Matthias R.; Cánovas, Héctor; Cieza, Lucas A.; Williams, Jonathan P.; Hales, Antonio; Ménard, Francois

    2015-06-20

    It is thought that planetary mass companions may form through gravitational disk instabilities or core accretion. Identifying such objects in the process of formation would provide the most direct test for the competing formation theories. One of the most promising candidates for a planetary mass object still in formation is the third object in the FW Tau system. We present here ALMA cycle 1 observations confirming the recently published 1.3 mm detection of a dust disk around this third object and present for the first time a clear detection of a single peak {sup 12}CO (2–1) line, providing direct evidence for the simultaneous existence of a gas disk. We perform radiative transfer modeling of the third object in FW Tau and find that current observations are consistent with either a brown dwarf embedded in an edge-on disk or a planet embedded in a low inclination disk, which is externally irradiated by the binary companion. Further observations with ALMA, aiming for high SNR detections of non-contaminated gas lines, are required to conclusively unveil the nature of the third object in FW Tau.

  7. ALMA Science Verification Data: Millimeter Continuum Polarimetry of the Bright Radio Quasar 3C 286

    NASA Astrophysics Data System (ADS)

    Nagai, H.; Nakanishi, K.; Paladino, R.; Hull, C. L. H.; Cortes, P.; Moellenbrock, G.; Fomalont, E.; Asada, K.; Hada, K.

    2016-06-01

    We present full-polarization observations of the compact, steep-spectrum radio quasar 3C 286 made with the Atacama Large Millimeter and Submillimeter Array (ALMA) at 1.3 mm. These are the first full-polarization ALMA observations, which were obtained in the framework of Science Verification. A bright core and a south–west component are detected in the total intensity image, similar to previous centimeter images. Polarized emission is also detected toward both components. The fractional polarization of the core is about 17%; this is higher than the fractional polarization at centimeter wavelengths, suggesting that the magnetic field is even more ordered in the millimeter radio core than it is further downstream in the jet. The observed polarization position angle (or electric vector position angle (EVPA)) in the core is ˜39◦, which confirms the trend that the EVPA slowly increases from centimeter to millimeter wavelengths. With the aid of multi-frequency VLBI observations, we argue that this EVPA change is associated with the frequency-dependent core position. We also report a serendipitous detection of a sub-mJy source in the field of view, which is likely to be a submillimeter galaxy.

  8. Resolving the extended atmosphere and the inner wind of Mira (o Ceti) with long ALMA baselines

    NASA Astrophysics Data System (ADS)

    Wong, K. T.; Kamiński, T.; Menten, K. M.; Wyrowski, F.

    2016-05-01

    Context. High angular resolution (sub)millimetre observations of asymptotic giant branch (AGB) stars, now possible with the Atacama Large Millimeter/submillimeter Array (ALMA), allow direct imaging of these objects' photospheres. The physical properties of the molecular material around these regions, which until now has only been studied by imaging of maser emission and spatially unresolved absorption spectroscopy, can be probed with radiative transfer modelling and compared to hydrodynamical model predictions. The prototypical Mira variable, o Cet (Mira), was observed as a Science Verification target in the 2014 ALMA Long Baseline Campaign, offering the first opportunity to study these physical conditions in detail. Aims: With the longest baseline of 15 km, ALMA produces clearly resolved images of the continuum and molecular line emission/absorption at an angular resolution of ~30 mas at 220 GHz. Models are constructed for Mira's extended atmosphere to investigate the physics and molecular abundances therein. Methods: We imaged the data of 28SiO ν= 0, 2J = 5-4 and H2O v2 = 1JKa,Kc = 55,0-64,3 transitions and extracted spectra from various lines of sight towards Mira's extended atmosphere. In the course of imaging the emission/absorption, we encountered ambiguities in the resulting images and spectra that appear to be related to the performance of the CLEAN algorithm when applied to a combination of extended emission, and compact emission and absorption. We addressed these issues by a series of tests and simulations. We derived the gas density, kinetic temperature, molecular abundance, and outflow/infall velocities in Mira's extended atmosphere by modelling the SiO and H2O lines. Results: We resolve Mira's millimetre continuum emission and our data are consistent with a radio photosphere with a brightness temperature of 2611 ± 51 K. In agreement with recent results obtained with the Very Large Array, we do not confirm the existence of a compact region (<5 mas) of

  9. The Sunyaev-Zel'dovich effect at 5″: RX J1347.5-1145 imaged by ALMA

    NASA Astrophysics Data System (ADS)

    Kitayama, Tetsu; Ueda, Shutaro; Takakuwa, Shigehisa; Tsutsumi, Takahiro; Komatsu, Eiichiro; Akahori, Takuya; Iono, Daisuke; Izumi, Takuma; Kawabe, Ryohei; Kohno, Kotaro; Matsuo, Hiroshi; Ota, Naomi; Suto, Yasushi; Takizawa, Motozaku; Yoshikawa, Kohji

    2016-10-01

    We present the first image of the thermal Sunyaev-Zel'dovich effect (SZE) obtained by the Atacama Large Millimeter/submillimeter Array (ALMA). Combining 7-m and 12-m arrays in Band 3, we create an SZE map toward a galaxy cluster RX J1347.5-1145 with 5″ resolution (corresponding to a physical size of 20 h-1 kpc), the highest angular and physical spatial resolutions achieved to-date for imaging the SZE, while retaining extended signals out to 40″. The 1 σ statistical sensitivity of the image is 0.017 mJy beam-1 or 0.12 mKCMB at the 5″ full width at half maximum. The SZE image shows a good agreement with an electron pressure map reconstructed independently from the X-ray data and offers a new probe of the small-scale structure of the intracluster medium. Our results demonstrate that ALMA is a powerful instrument for imaging the SZE in compact galaxy clusters with unprecedented angular resolution and sensitivity. As the first report on the detection of the SZE by ALMA, we present detailed analysis procedures including corrections for the missing flux, to provide guiding methods for analyzing and interpreting future SZE images obtained by ALMA.

  10. The SCUBA-2 Cosmology Legacy Survey: ALMA Resolves the Bright-end of the Sub-millimeter Number Counts

    NASA Astrophysics Data System (ADS)

    Simpson, J. M.; Smail, Ian; Swinbank, A. M.; Chapman, S. C.; Geach, J. E.; Ivison, R. J.; Thomson, A. P.; Aretxaga, I.; Blain, A. W.; Cowley, W. I.; Chen, Chian-Chou; Coppin, K. E. K.; Dunlop, J. S.; Edge, A. C.; Farrah, D.; Ibar, E.; Karim, A.; Knudsen, K. K.; Meijerink, R.; Michałowski, M. J.; Scott, D.; Spaans, M.; van der Werf, P. P.

    2015-07-01

    We present high-resolution 870 μm Atacama Large Millimeter/sub-millimeter Array (ALMA) continuum maps of 30 bright sub-millimeter sources in the UKIDSS UDS field. These sources are selected from deep, 1 degree2 850 μm maps from the SCUBA-2 Cosmology Legacy Survey, and are representative of the brightest sources in the field (median {S}{SCUBA-2} = 8.7 ± 0.4 mJy). We detect 52 sub-millimeter galaxies (SMGs) at >4σ significance in our 30 ALMA maps. In {61}-15+19% of the ALMA maps the single-dish source comprises a blend of ≥2 SMGs, where the secondary SMGs are Ultra-luminous Infrared Galaxies (ULIRGs) with {L}{IR} ≳ 1012 {\\text{}}{L}⊙ . The brightest SMG contributes on average {80}-2+6% of the single-dish flux density, and in the ALMA maps containing ≥2 SMGs the secondary SMG contributes {25}-5+1% of the integrated ALMA flux. We construct source counts and show that multiplicity boosts the apparent single-dish cumulative counts by 20% at S870 > 7.5 mJy, and by 60% at S870 > 12 mJy. We combine our sample with previous ALMA studies of fainter SMGs and show that the counts are well-described by a double power law with a break at 8.5 ± 0.6 mJy. The break corresponds to a luminosity of ˜6 × 1012 {\\text{}}{L}⊙ or a star formation rate (SFR) of ˜103 {\\text{}}{M}⊙ {{yr}}-1. For the typical sizes of these SMGs, which are resolved in our ALMA data with {R}{{e}} = 1.2 ± 0.1 kpc, this yields a limiting SFR density of ˜100 {\\text{}}{M}⊙ yr-1 kpc-2 Finally, the number density of S870 ≳ 2 mJy SMGs is 80 ± 30 times higher than that derived from blank-field counts. An over-abundance of faint SMGs is inconsistent with line-of-sight projections dominating multiplicity in the brightest SMGs, and indicates that a significant proportion of these high-redshift ULIRGs are likely to be physically associated.

  11. Formation, Detection and the Distribution of Complex Organic Molecules with the Atacama Large Millimeter/submillimeter Array (ALMA)

    NASA Astrophysics Data System (ADS)

    Remijan, Anthony John

    2015-08-01

    The formation and distribution of complex organic material in astronomical environments continues to be a focused research area in astrochemistry. For several decades now, emphasis has been placed on the millimeter/submillimeter regime of the radio spectrum for trying to detect new molecular species and to constrain the chemical formation route of complex molecules by comparing and contrasting their relative distributions towards varying astronomical environments. This effort has been extremely laborious as millimeter/submillimeter facilities have been only able to detect and map the distribution of the strongest transition(s) of the simplest organic molecules. Even then, these single transition "chemical maps" have been very low spatial resolution because early millimeter/submillimeter facilities did not have access to broadband spectral coverage or the imaging capabilities to truly ascertain the morphology of the molecular emission. In the era of ALMA, these limitations have been greatly lifted. Broadband spectral line surveys now hold the key to uncovering the full molecular complexity in astronomical environments. In addition, searches for complex organic material is no longer limited to investigating the strongest lines of the simplest molecules toward the strongest sources of emission in the Galaxy. ALMA is issuing a new era of exploration as the search for complex molecules will now be available to an increased suite of sources in the Galaxy and our understanding of the formation of this complex material will be greatly increased as a result. This presentation will highlight the current and future ALMA capabilities in the search for complex molecules towards astronomical environments, highlight the recent searches that ALMA scientists have conducted from the start of ALMA Early Science and provide the motivation for the next suite of astronomical searches to investigate our pre-biotic origins in the universe.

  12. Closing the Loop for ALMA - Three antennas working in unison open new bright year for revolutionary observatory

    NASA Astrophysics Data System (ADS)

    2010-01-01

    The Atacama Large Millimeter/submillimeter Array (ALMA) has passed a key milestone crucial for the high quality images that will be the trademark of this revolutionary new tool for astronomy. Astronomers and engineers have, for the first time, successfully linked three of the observatory's antennas at the 5000-metre elevation observing site in northern Chile. Having three antennas observing in unison paves the way for precise images of the cool Universe at unprecedented resolution, by providing the missing link to correct errors that arise when only two antennas are used. On 20 November 2009 the third antenna for the ALMA observatory was successfully installed at the Array Operations Site, the observatory's "high site" on the Chajnantor plateau, at an altitude of 5000 metres in the Chilean Andes. Later, after a series of technical tests, astronomers and engineers observed the first signals from an astronomical source making use of all three 12-metre diameter antennas linked together, and are now working around the clock to establish the stability and readiness of the system. "The first signal using just two ALMA antennas, observed in October, can be compared to a baby's first babblings," says Leonardo Testi, the European Project Scientist for ALMA at ESO. "Observing with a third antenna represents the moment when the baby says its very first, meaningful word - not yet a full sentence, but overwhelmingly exciting! The linking of three antennas is indeed the first actual step towards our goal of achieving precise and sharp images at submillimetre wavelengths." The successful linking of the antenna trio was a key test of the full electronic and software system now being installed at ALMA, and its success anticipates the future capabilities of the observatory. When complete, ALMA will have at least 66 high-tech antennas operating together as an "interferometer", working as a single, huge telescope probing the sky in the millimetre and submillimetre wavelengths of light

  13. ALMA observations of gas and dust in the coma of comet C/2012 S1 (ISON)

    NASA Astrophysics Data System (ADS)

    Cordiner, M.; Remijan, A.; Milam, S.; Mumma, M.; Charnley, S.; Paganini, L.; Boissier, J.; Villanueva, G.; Bockelee-Morvan, D.; Biver, N.; Kuan, Y.; Lis, D.; Crovisier, J.; Coulson, I.; Minniti, D.

    2014-07-01

    Ground-based studies of cometary comae provide indirect information on the compositions of the nuclear ices, and thus provide insight into the physical and chemical conditions of the early solar nebula. To realize the full potential of gas-phase coma observations as probes of solar-system evolution requires a complete understanding of the gas-release mechanisms. However, previous observations have been unable to ascertain the precise origins of fundamental coma species including H_2CO, HCN, and HNC, and details regarding the possible formation of these species in the coma are not well understood. Here, we present spatially and spectrally-resolved ALMA sub-mm images of the distributions of HCN, HNC, CH_3OH, H_2CO, and dust in the coma of comet C/2012 S1 (ISON), observed during the outburst event on November 15-17 (at r_H = 0.54-0.61 au and Δ = 0.9 au). Our observations reveal an unprecedented level of detail in the distributions of these fundamental coma constituents, and permit accurate measurement of their origins in the coma. Observations were made using ALMA Band 7 in Cycle 1 (Early Science) mode in the frequency range 339-364 GHz, with 25-29 12-m antennae. Weather conditions were excellent, with good atmospheric phase stability and low precipitable water vapor (0.5-0.8 mm at zenith). The spatial resolution was 0.4-0.8'' (with maximum recoverable angular scales approx. 5-10''), and the spectral resolution was 0.4 km s^{-1}. The ALMA image cubes show kinematically and spatially-resolved structures in HCN, HNC, CH_3OH, and H_2CO emission. Whereas the CH_3OH and HCN distributions are consistent with release from (or within 100 km of) the nucleus, the H_2CO data indicate coma release from a parent species with scale-length on the order of a few hundred km. The HNC distribution suggests release in clumpy, collimated outflows possibly as a result of the breakdown of a macromolecular/dust precursor. Clear 0.9-mm continuum emission was detected, showing a sharp central

  14. ALMA reveals the feeding of the Seyfert 1 nucleus in NGC 1566

    NASA Astrophysics Data System (ADS)

    Combes, F.; García-Burillo, S.; Casasola, V.; Hunt, L. K.; Krips, M.; Baker, A. J.; Boone, F.; Eckart, A.; Marquez, I.; Neri, R.; Schinnerer, E.; Tacconi, L. J.

    2014-05-01

    We report ALMA observations of CO(3-2) emission in the Seyfert 1 galaxy NGC 1566, at a spatial resolution of 25 pc. Our aim is to investigate the morphology and dynamics of the gas inside the central kpc, and to probe nuclear fueling and feedback phenomena. NGC 1566 has a nuclear bar of 1.7 kpc radius and a conspicuous grand design spiral starting from this radius. The ALMA field of view, of diameter 0.9 kpc, lies well inside the nuclear bar and reveals a molecular trailing spiral structure from 50 to 300 pc in size, which is contributing to fuel the nucleus, according to its negative gravity torques. The spiral starts with a large pitch angle from the center and then winds up in a pseudo-ring at the inner Lindblad resonance (ILR) of the nuclear bar. This is the first time that a trailing spiral structure is clearly seen driving the gas inwards inside the ILR ring of the nuclear bar. This phenomenon shows that the massive central black hole has a significant dynamical influence on the gas, triggering its fueling. The gaseous spiral is well correlated with the dusty spiral seen through extinction in HST images, and also with a spiral feature emitting 0.87 mm continuum. This continuum emission must come essentially from cold dust heated by the interstellar radiation field. The HCN(4-3) and HCO+(4-3) lines were simultaneously mapped and detected in the nuclear spiral. The HCO+(4-3) line is 3 times stronger than the HCN(4-3), as expected when star formation excitation dominates over active galactic nucleus (AGN) heating. The CO(3-2)/HCO+(4-3) integrated intensity ratio is ~100. The molecular gas is in remarkably regular rotation, with only slight non-circular motions at the periphery of the nuclear spiral arms. These perturbations are quite small, and no outflow nor AGN feedback is detected. Based on observations carried out with ALMA in cycle 0.

  15. Local Instability Signatures in ALMA Observations of Dense Gas in NGC 7469

    NASA Astrophysics Data System (ADS)

    Fathi, Kambiz; Izumi, Takuma; Romeo, Alessandro B.; Martín, Sergio; Imanishi, Masatoshi; Hatziminaoglou, Evanthia; Aalto, Susanne; Espada, Daniel; Kohno, Kotaro; Krips, Melanie; Matsushita, Satoki; Meier, David S.; Nakai, Naomasa; Terashima, Yuichi

    2015-06-01

    We present an unprecedented measurement of the disk stability and local instability scales in the luminous infrared Seyfert 1 host, NGC 7469, based on ALMA observations of dense gas tracers and with a synthesized beam of 165 × 132 pc. While we confirm that non-circular motions are not significant in redistributing the dense interstellar gas in this galaxy, we find compelling evidence that the dense gas is a suitable tracer for studying the origin of its intensely high-mass star-forming ringlike structure. Our derived disk stability parameter Q accounts for a thick disk structure, and its value falls below unity at the radii in which intense star formation is found. Furthermore, we derive the characteristic instability scale {λ }c and find a striking agreement between our measured scale of ∼180 pc and the typical sizes of individual complexes of young and massive star clusters seen in high-resolution images.

  16. ALMA-backed NIR high resolution integral field spectroscopy of the NUGA galaxy NGC 1433

    NASA Astrophysics Data System (ADS)

    Smajić, Semir; Moser, Lydia; Eckart, Andreas; Valencia-S., Mónica; Combes, Françoise; Horrobin, Matthew; García-Burillo, Santiago; García-Marín, Macarena; Fischer, Sebastian; Zuther, Jens

    2014-07-01

    Aims: We present the results of near-infrared (NIR) H- and K-band European Southern Observatory SINFONI integral field spectroscopy (IFS) of the Seyfert 2 galaxy NGC 1433. We investigate the central 500 pc of this nearby galaxy, concentrating on excitation conditions, morphology, and stellar content. NGC 1433 was selected from our extended NUGA(-south) sample, which was additionally observed with the Atacama Large Millimeter/submillimeter Array (ALMA). NGC 1433 is a ringed, spiral galaxy with a main stellar bar in roughly east-west direction (PA 94°) and a secondary bar in the nuclear region (PA 31°). Several dusty filaments are detected in the nuclear region with the Hubble Space Telescope. ALMA detects molecular CO emission coinciding with these filaments. The active galactic nucleus is not strong and the galaxy is also classified as a low-ionization emission-line region (LINER). Methods: The NIR is less affected by dust extinction than optical light and is sensitive to the mass-dominating stellar populations. SINFONI integral field spectroscopy combines NIR imaging and spectroscopy, allowing us to analyse several emission and absorption lines to investigate the stellar populations and ionization mechanisms over the 10″ × 10″ field of view (FOV). Results: We present emission and absorption line measurements in the central kpc of NGC 1433. We detect a narrow Balmer line and several H2 lines. We find that the stellar continuum peaks in the optical and NIR in the same position, indicating that there is no covering of the center by a nuclear dust lane. A strong velocity gradient is detected in all emission lines at that position. The position angle of this gradient is at 155° whereas the galactic rotation is at a position angle of 201°. Our measures of the molecular hydrogen lines, hydrogen recombination lines, and [Fe ii] indicate that the excitation at the nucleus is caused by thermal excitation, i.e., shocks that can be associated with active galactic

  17. An ALMA view of the post-AGB object HD 101584

    NASA Astrophysics Data System (ADS)

    Olofsson, H.; Vlemmings, W.; Maercker, M.; Humphreys, E.; Lindqvist, M.; Nyman, L.; Ramstedt, S.

    2016-07-01

    ALMA cycles 1 and 3 observations of CO isotopologues and 1.3mm continuum are used in a study of the circumstellar environment of the binary HD 101584, a post-AGB star and a low-mass companion that is most likely a post-common-envelope-evolution system. These data are supplemented with new information from OH maser emission. It is inferred that the large- scale circumstellar medium has a bipolar hour-glass structure, seen almost pole-on, formed by an energetic, ≥⃒ 150 km s-1, jet. Significant amount of material still resides in the central region. It is proposed that the circumstellar morphology is related to an event which took place ≤⃒ 500 yr ago, possibly a capture event where the companion spiralled in towards the AGB star. Several observed features remain to be explained, and may hint to a more complicated scenario.

  18. ALMA Observation of Neptune's Spatially-resolved Stratospheric HCN ( J = 4-3)

    NASA Astrophysics Data System (ADS)

    Iino, Takahiro; Nakamoto, Satoru; Tsukagoshi, Takashi; Tanaka, Kunihiko; Tanaka, Yuki; Hirahara, Yasuhiro

    2016-10-01

    Neptune's stratospheric HCN(J = 4 - 3) rotational transition was observed by Atacama Large Millimeter-submillimeter Array (ALMA). 19 12-m antennas with the Band-7 receivers spatially resolved Neptune's 2.3'' diameter disk with 0.4'' times 0.6'' synthesized beam. The HCN emission line was clearly detected on the entire disk. The wind velocity map of the stratosphere was illustrated by the Doppler-shift analysis of the HCN emission, and the structured zonal wind whose maximum velocity reaches as high as 600 m/s in the high latitude region of the southern hemisphere was detected. Respective the westward and eastward zonal winds were observed for the northern and southern hemisphere.

  19. A detailed view of the gas shell around R Sculptoris with ALMA

    NASA Astrophysics Data System (ADS)

    Maercker, M.; Vlemmings, W. H. T.; Brunner, M.; De Beck, E.; Humphreys, E. M.; Kerschbaum, F.; Lindqvist, M.; Olofsson, H.; Ramstedt, S.

    2016-02-01

    Context. During the asymptotic giant branch (AGB) phase, stars undergo thermal pulses - short-lived phases of explosive helium burning in a shell around the stellar core. Thermal pulses lead to the formation and mixing-up of new elements to the stellar surface. They are hence fundamental to the chemical evolution of the star and its circumstellar envelope. A further consequence of thermal pulses is the formation of detached shells of gas and dust around the star, several of which have been observed around carbon-rich AGB stars. Aims: We aim to determine the physical properties of the detached gas shell around R Sculptoris, in particular the shell mass and temperature, and to constrain the evolution of the mass-loss rate during and after a thermal pulse. Methods: We analyse 12CO(1-0), 12CO(2-1), and 12CO(3-2) emission, observed with the Atacama Large Millimeter/submillimeter Array (ALMA) during Cycle 0 and complemented by single-dish observations. The spatial resolution of the ALMA data allows us to separate the detached shell emission from the extended emission inside the shell. We perform radiative transfer modelling of both components to determine the shell properties and the post-pulse mass-loss properties. Results: The ALMA data show a gas shell with a radius of 19.̋5 expanding at 14.3 km s-1. The different scales probed by the ALMA Cycle 0 array show that the shell must be entirely filled with gas, contrary to the idea of a detached shell. The comparison to single-dish spectra and radiative transfer modelling confirms this. We derive a shell mass of 4.5 × 10-3 M⊙ with a temperature of 50 K. Typical timescales for thermal pulses imply a pulse mass-loss rate of 2.3 × 10-5 M⊙ yr-1. For the post-pulse mass-loss rate, we find evidence for a gradual decline of the mass-loss rate, with an average value of 1.6 × 10-5 M⊙ yr-1. The total amount of mass lost since the last thermal pulse is 0.03 M⊙, a factor four higher compared to classical models, with a

  20. Origin and Kinematics of the Eruptive Flow from XZ Tau Revealed by ALMA

    NASA Astrophysics Data System (ADS)

    Zapata, Luis A.; Galván-Madrid, Roberto; Carrasco-González, Carlos; Curiel, Salvador; Palau, Aina; Rodríguez, Luis F.; Kurtz, Stan E.; Tafoya, Daniel; Loinard, Laurent

    2015-09-01

    We present high angular resolution (˜0.″94) 12CO(1-0) Atacama Large Millimeter/submillimeter Array (ALMA) observations obtained during the 2014 long baseline campaign from the eruptive bipolar flow from the multiple XZ Tau stellar system discovered by the Hubble Space Telescope (HST). These observations reveal, for the first time, the kinematics of the molecular flow. The kinematics of the different ejections close to XZ Tau reveal a rotating and expanding structure with a southeast-northwest velocity gradient. The youngest eruptive bubbles unveiled in the optical HST images are inside of this molecular expanding structure. Additionally, we report a very compact and collimated bipolar outflow emanating from XZ Tau A, which indicates that the eruptive outflow is indeed originating from this object. The mass (3 × 10-7 M⊙) and energetics (Ekin = 3 × 1037 erg) for the collimated outflow are comparable to those found in molecular outflows associated with young brown dwarfs.

  1. ALMA observations of Titan : Vertical and spatial distribution of HNC and C2H5CN

    NASA Astrophysics Data System (ADS)

    Moreno, Raphael; Lellouch, Emmanuel; Vinatier, Sandrine; Gurwell, Mark A.; Moullet, Arielle; Hidayat, Taufiq

    2016-10-01

    We report submm observations of Titan performed with the ALMA interferometer centered at the rotational frequencies of HCN(4-3) and HNC(4-3), i.e. 354 and 362 GHz. These measurements yielded disk-resolved emission spectra of Titan with an angular resolution of ~0.47''. Titan's angular surface diameter was 0.77''. Data were acquired in summer 2012 near the greatest eastern and western elongations of Titan at a spectral resolution of 122 kHz (λ/d λ = 3106).We have obtained maps of several nitriles present in Titan' stratosphere: HCN, HC3N, CH3CN, HNC, C2H5CN and other weak lines (isotopes, vibrationnally excited lines).We will present radiative transfer analysis of the spectra acquired focused on HNC and C2H5CN. With the combination of all these detected rotational lines, we will constrain the spatial and vertical distribution of these species.

  2. Poster 8: ALMA observations of Titan : Vertical and spatial distributions of nitriles

    NASA Astrophysics Data System (ADS)

    Moreno, Raphael; Lellouch, Emmanuel; Vinatier, Sandrine; Gurwell, Mark; Moullet, Arielle; Lara, Luisa; Hidayat, Taufiq

    2016-06-01

    We report submm observations of Titan performed with the ALMA interferometer centered at the rotational frequencies of HCN(4-3) and HNC(4-3), i.e. 354 and 362 GHz. These measurements yielded disk-resolved emission spectra of Titan with an angular resolution of ˜0.47". Titan's angular surface diameter was 0.77". Data were acquired in summer 2012 near the greatest eastern and western elongations of Titan at a spectral resolution of 122 kHz (λ/dλ = 3106). We will present radiative transfer analysis of the acquired spectra. With the combination of all the detected rotational lines, we will constrain the atmospheric temperature, the spatial and vertical distribution HCN, HC3N, CH3CN, HNC, C2H5CN, as well as isotopic ratios.

  3. ALMA OBSERVATIONS OF THE MASSIVE MOLECULAR OUTFLOW G331.512-0.103

    SciTech Connect

    Merello, Manuel; Bronfman, Leonardo; Garay, Guido; Lo, Nadia; Evans, Neal J. II; Nyman, Lars-Ake; Cortes, Juan R.; Cunningham, Maria R.

    2013-09-01

    The object of this study is one of the most energetic and luminous molecular outflows known in the Galaxy, G331.512-0.103. Observations with ALMA Band 7 (350 GHz; 0.86 mm) reveal a very compact, extremely young bipolar outflow and a more symmetric outflowing shocked shell surrounding a very small region of ionized gas. The velocities of the bipolar outflow are about 70 km s{sup -1} on either side of the systemic velocity. The expansion velocity of the shocked shell is {approx}24 km s{sup -1}, implying a crossing time of about 2000 yr. Along the symmetry axis of the outflow, there is a velocity feature, which could be a molecular ''bullet'' of high-velocity dense material. The source is one of the youngest examples of massive molecular outflow found associated with a high-mass star.

  4. CONSTRAINING THE PLANETARY SYSTEM OF FOMALHAUT USING HIGH-RESOLUTION ALMA OBSERVATIONS

    SciTech Connect

    Boley, A. C.; Payne, M. J.; Ford, E. B.; Shabram, M.; Corder, S.; Dent, W. R. F.

    2012-05-01

    The dynamical evolution of planetary systems leaves observable signatures in debris disks. Optical images trace micron-sized grains, which are strongly affected by stellar radiation and need not coincide with their parent body population. Observations of millimeter-sized grains accurately trace parent bodies, but previous images lack the resolution and sensitivity needed to characterize the ring's morphology. Here we present ALMA 350 GHz observations of the Fomalhaut debris ring. These observations demonstrate that the parent body population is 13-19 AU wide with a sharp inner and outer boundary. We discuss three possible origins for the ring and suggest that debris confined by shepherd planets is the most consistent with the ring's morphology.

  5. Constraining turbulence mixing strength in transitional discs with planets using SPHERE and ALMA

    NASA Astrophysics Data System (ADS)

    de Juan Ovelar, M.; Pinilla, P.; Min, M.; Dominik, C.; Birnstiel, T.

    2016-06-01

    We investigate the effect that the turbulent mixing strength parameter αturb plays on near-infrared polarimetric and sub-millimetre interferometric imaging observations of transitional discs (TDs) with a gap carved by a planet. We generate synthetic observations of these objects with ALMA and VLT/SPHERE-ZIMPOL by combining hydrodynamical, dust evolution, radiative transfer and instrument models for values of α _{turb}=[10^{-4}, 10^{-3}, 10^{-2}]. We find that, through a combination of effects on the viscosity of the gas, the turbulent mixing and dust evolution processes, αturb strongly affects the morphology of the dust distribution that can be traced with these observations. We constrain the value of αturb to be within an order of magnitude of 10-3 in TD sources that show cavities in sub-mm continuum images while featuring continuous distribution of dust or smaller cavities in NIR-polarimetric images.

  6. Long Wavelength Observations of Thermal Emission from Pluto and Charon with ALMA

    NASA Astrophysics Data System (ADS)

    Butler, Bryan J.; Gurwell, Mark; Lellouch, Emmanuel; Moullet, Arielle; Moreno, Raphael; Bockelee-Morvan, Dominique; Biver, Nicolas; Fouchet, Thierry; Lis, Darek; Stern, Alan; Young, Leslie; Young, Eliot; Weaver, Hal; Boissier, Jeremie; Stansberry, John

    2015-11-01

    Long wavelength observations of Pluto can determine atmospheric temperatures, abundances, and vertical distributions for those molecules that have transitions at these wavelengths. In addition, observations of both Pluto and Charon can elucidate their surface and subsurface temperatures and surface compositions (and distribution, with enough resolution). We have used the Atacama Large Millimeter Array (ALMA) to observe the CO and HCN in the atmosphere of Pluto, and to observe thermal emission from the two bodies, where the resolution is enough to separate them (but not enough to resolve each individually). We report here on the thermal emission observations, and separately at this meeting on the CO [1] and HCN [2] observations. We observed the Pluto/Charon system with ALMA on June 12 and 13, 2015, at a wavelength of ~0.86 mm. Both days provide separate observations of the thermal emission from Pluto and Charon. We find a preliminary value of the brightness temperature of the two bodies of 35 K and 46 K with variation of less than 1 K between the two days and SNR of > 300 for Pluto and > 100 for Charon. This is similar to previous observations of the separate thermal emission of the two bodies with the Submillimeter Array (SMA) [3] and Very Large Array (VLA) [4]. We will discuss the implications of these measured brightness temperatures and the apparent lack of significant variation between the two days (longitudes).[1] Gurwell et al., this meeting. [2] Lellouch et al., this meeting. [3] Gurwell & Butler, BAAS 37, 2005. [4] Butler et al. BAAS 43, 2010.

  7. Detection of the Simplest Sugar, Glycolaldehyde, in a Solar-type Protostar with ALMA

    NASA Astrophysics Data System (ADS)

    Jørgensen, Jes K.; Favre, Cécile; Bisschop, Suzanne E.; Bourke, Tyler L.; van Dishoeck, Ewine F.; Schmalzl, Markus

    2012-09-01

    Glycolaldehyde (HCOCH2OH) is the simplest sugar and an important intermediate in the path toward forming more complex biologically relevant molecules. In this Letter we present the first detection of 13 transitions of glycolaldehyde around a solar-type young star, through Atacama Large Millimeter Array (ALMA) observations of the Class 0 protostellar binary IRAS 16293-2422 at 220 GHz (6 transitions) and 690 GHz (7 transitions). The glycolaldehyde lines have their origin in warm (200-300 K) gas close to the individual components of the binary. Glycolaldehyde co-exists with its isomer, methyl formate (HCOOCH3), which is a factor 10-15 more abundant toward the two sources. The data also show a tentative detection of ethylene glycol, the reduced alcohol of glycolaldehyde. In the 690 GHz data, the seven transitions predicted to have the highest optical depths based on modeling of the 220 GHz lines all show redshifted absorption profiles toward one of the components in the binary (IRAS 16293B) indicative of infall and emission at the systemic velocity offset from this by about 0farcs2 (25 AU). We discuss the constraints on the chemical formation of glycolaldehyde and other organic species—in particular, in the context of laboratory experiments of photochemistry of methanol-containing ices. The relative abundances appear to be consistent with UV photochemistry of a CH3OH-CO mixed ice that has undergone mild heating. The order of magnitude increase in line density in these early ALMA data illustrates its huge potential to reveal the full chemical complexity associated with the formation of solar system analogs.

  8. ALMA OBSERVATIONS OF THE COLDEST PLACE IN THE UNIVERSE: THE BOOMERANG NEBULA

    SciTech Connect

    Sahai, R.; Vlemmings, W. H. T.; Huggins, P. J.; Nyman, L.-Å.; Gonidakis, I.

    2013-11-10

    The Boomerang Nebula is the coldest known object in the universe, and an extreme member of the class of pre-planetary nebulae, objects which represent a short-lived transitional phase between the asymptotic giant branch and planetary nebula evolutionary stages. Previous single-dish CO (J = 1-0) observations (with a 45'' beam) showed that the high-speed outflow in this object has cooled to a temperature significantly below the temperature of the cosmic background radiation. Here we report the first observations of the Boomerang Nebula with ALMA in the CO J = 2-1 and J = 1-0 lines to resolve the structure of this ultra-cold nebula. We find a central hourglass-shaped nebula surrounded by a patchy, but roughly round, cold high-velocity outflow. We compare the ALMA data with visible-light images obtained with the Hubble Space Telescope and confirm that the limb-brightened bipolar lobes seen in these data represent hollow cavities with dense walls of molecular gas and dust producing both the molecular-emission-line and scattered-light structures seen at millimeter and visible wavelengths. The large diffuse biconical shape of the nebula seen in the visible wavelength range is likely due to preferential illumination of the cold, high-velocity outflow. We find a compact source of millimeter-wave continuum in the nebular waist—these data, together with sensitive upper limits on the radio continuum using observations with ATCA, indicate the presence of a substantial mass of very large (millimeter-sized) grains in the waist of the nebula. Another unanticipated result is the detection of CO emission regions beyond the ultra-cold region which indicate the re-warming of the cold gas, most likely due to photoelectric grain heating.

  9. DETECTION OF THE SIMPLEST SUGAR, GLYCOLALDEHYDE, IN A SOLAR-TYPE PROTOSTAR WITH ALMA

    SciTech Connect

    Jorgensen, Jes K.; Bisschop, Suzanne E.; Favre, Cecile; Bourke, Tyler L.; Van Dishoeck, Ewine F.; Schmalzl, Markus E-mail: suzanne@snm.ku.dk E-mail: tbourke@cfa.harvard.edu E-mail: schmalzl@strw.leidenuniv.nl

    2012-09-20

    Glycolaldehyde (HCOCH{sub 2}OH) is the simplest sugar and an important intermediate in the path toward forming more complex biologically relevant molecules. In this Letter we present the first detection of 13 transitions of glycolaldehyde around a solar-type young star, through Atacama Large Millimeter Array (ALMA) observations of the Class 0 protostellar binary IRAS 16293-2422 at 220 GHz (6 transitions) and 690 GHz (7 transitions). The glycolaldehyde lines have their origin in warm (200-300 K) gas close to the individual components of the binary. Glycolaldehyde co-exists with its isomer, methyl formate (HCOOCH{sub 3}), which is a factor 10-15 more abundant toward the two sources. The data also show a tentative detection of ethylene glycol, the reduced alcohol of glycolaldehyde. In the 690 GHz data, the seven transitions predicted to have the highest optical depths based on modeling of the 220 GHz lines all show redshifted absorption profiles toward one of the components in the binary (IRAS 16293B) indicative of infall and emission at the systemic velocity offset from this by about 0.''2 (25 AU). We discuss the constraints on the chemical formation of glycolaldehyde and other organic species-in particular, in the context of laboratory experiments of photochemistry of methanol-containing ices. The relative abundances appear to be consistent with UV photochemistry of a CH{sub 3}OH-CO mixed ice that has undergone mild heating. The order of magnitude increase in line density in these early ALMA data illustrates its huge potential to reveal the full chemical complexity associated with the formation of solar system analogs.

  10. Linearly polarized millimeter and submillimeter continuum emission of Sgr A* constrained by ALMA

    NASA Astrophysics Data System (ADS)

    Liu, Hauyu Baobab; Wright, Melvyn C. H.; Zhao, Jun-Hui; Brinkerink, Christiaan D.; Ho, Paul T. P.; Mills, Elisabeth A. C.; Martín, Sergio; Falcke, Heino; Matsushita, Satoki; Martí-Vidal, Ivan

    2016-09-01

    Aims: Our aim is to characterize the polarized continuum emission properties including intensity, polarization position angle, and polarization percentage of Sgr A* at ~100 (3.0 mm), ~230 (1.3 mm), ~345 (0.87 mm), ~500 (0.6 mm), and ~700 GHz (0.43 mm). Methods: We report continuum emission properties of Sgr A* at the above frequency bands, based on the Atacama Large Millimeter Array (ALMA) observations. We measured flux densities of Sgr A* from ALMA single pointing and mosaic observations. We performed sinusoidal fittings to the observed (XX-YY)/I intensity ratios, to derive the polarization position angles and polarization percentages. Results: We successfully detect polarized continuum emission from all observed frequency bands. We observed lower Stokes I intensity at ~700 GHz than that at ~500 GHz, which suggests that emission at ≳500 GHz is from the optically thin part of a synchrotron emission spectrum. Both the Stokes I intensity and the polarization position angle at our highest observing frequency of ~700 GHz, may vary with time. However, as yet we do not detect variation in the polarization percentage at >500 GHz. The polarization percentage at ~700 GHz is likely lower than that at ~500 GHz. By comparing the ~500 GHz and ~700 GHz observations with the observations at lower frequency bands, we suggest that the intrinsic polarization position angle of Sgr A* varies with time. This paper also reports the measurable polarization properties from the observed calibration quasars. Conclusions: Future simultaneous multi-frequency polarization observations are required to clarify the time and frequency variation of the polarization position angle and polarization percentage.

  11. ALMA Imaging of the CO (6-5) Line Emission in NGC 7130*

    NASA Astrophysics Data System (ADS)

    Zhao, Yinghe; Lu, Nanyao; Xu, C. Kevin; Gao, Yu; Barcos-Munõz, Loreto; Díaz-Santos, Tanio; Appleton, Philip; Charmandaris, Vassilis; Armus, Lee; van der Werf, Paul; Evans, Aaron; Cao, Chen; Inami, Hanae; Murphy, Eric

    2016-04-01

    In this paper, we report our high-resolution (0.″20 × 0.″14 or ˜70 × 49 pc) observations of the CO(6-5) line emission, which probes warm and dense molecular gas, and the 434 μm dust continuum in the nuclear region of NGC 7130, obtained with the Atacama Large Millimeter Array (ALMA). The CO line and dust continuum fluxes detected in our ALMA observations are 1230 ± 74 Jy km s-1 and 814 ± 52 mJy, respectively, which account for 100% and 51% of their total fluxes. We find that the CO(6-5) and dust emissions are generally spatially correlated, but their brightest peaks show an offset of ˜70 pc, suggesting that the gas and dust emissions may start decoupling at this physical scale. The brightest peak of the CO(6-5) emission does not spatially correspond to the radio continuum peak, which is likely dominated by an active galactic nucleus (AGN). This, together with our additional quantitative analysis, suggests that the heating contribution of the AGN to the CO(6-5) emission in NGC 7130 is negligible. The CO(6-5) and the extinction-corrected Pa-α maps display striking differences, suggestive of either a breakdown of the correlation between warm dense gas and star formation at linear scales of <100 pc or a large uncertainty in our extinction correction to the observed Pa-α image. Over a larger scale of ˜2.1 kpc, the double-lobed structure found in the CO(6-5) emission agrees well with the dust lanes in the optical/near-infrared images. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

  12. ALMA Observations of Warm Molecular Gas and Cold Dust in NGC 34

    NASA Astrophysics Data System (ADS)

    Xu, C. K.; Cao, C.; Lu, N.; Gao, Y.; van der Werf, P.; Evans, A. S.; Mazzarella, J. M.; Chu, J.; Haan, S.; Diaz-Santos, T.; Meijerink, R.; Zhao, Y.-H.; Appleton, P.; Armus, L.; Charmandaris, V.; Lord, S.; Murphy, E. J.; Sanders, D. B.; Schulz, B.; Stierwalt, S.

    2014-05-01

    We present Atacama Large Millimeter Array (ALMA) Cycle-0 observations of the CO (6-5) line emission (rest-frame frequency = 691.473 GHz) and of the 435 μm dust continuum emission in the nuclear region of NGC 34, a local luminous infrared galaxy at a distance of 84 Mpc (1'' = 407 pc) which contains a Seyfert 2 active galactic nucleus (AGN) and a nuclear starburst. The CO emission is well resolved by the ALMA beam (0.''26 × 0.''23), with an integrated flux of f CO(6-5) = 1004 (± 151) Jy km s-1. Both the morphology and kinematics of the CO (6-5) emission are rather regular, consistent with a compact rotating disk with a size of 200 pc. A significant emission feature is detected on the redshifted wing of the line profile at the frequency of the H13CN (8-7) line, with an integrated flux of 17.7 ± 2.1(random) ± 2.7(systematic) Jy km s-1. However, it cannot be ruled out that the feature is due to an outflow of warm dense gas with a mean velocity of 400 km s-1. The continuum is resolved into an elongated configuration, and the observed flux corresponds to a dust mass of M dust = 106.97 ± 0.13 M ⊙. An unresolved central core (radius ~= 50 pc) contributes 28% of the continuum flux and 19% of the CO (6-5) flux, consistent with insignificant contributions of the AGN to both emissions. Both the CO (6-5) and continuum spatial distributions suggest a very high gas column density (gsim 104 M ⊙ pc-2) in the nuclear region at radius <~ 100 pc. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

  13. ALMA observations of warm molecular gas and cold dust in NGC 34

    SciTech Connect

    Xu, C. K.; Cao, C.; Lu, N.; Mazzarella, J. M.; Diaz-Santos, T.; Zhao, Y.-H.; Appleton, P.; Armus, L.; Lord, S.; Murphy, E. J.; Schulz, B.; Gao, Y.; Van der Werf, P.; Meijerink, R.; Evans, A. S.; Stierwalt, S.; Chu, J.; Sanders, D. B.; Haan, S.; Charmandaris, V.

    2014-05-20

    We present Atacama Large Millimeter Array (ALMA) Cycle-0 observations of the CO (6-5) line emission (rest-frame frequency = 691.473 GHz) and of the 435 μm dust continuum emission in the nuclear region of NGC 34, a local luminous infrared galaxy at a distance of 84 Mpc (1'' = 407 pc) which contains a Seyfert 2 active galactic nucleus (AGN) and a nuclear starburst. The CO emission is well resolved by the ALMA beam (0.''26 × 0.''23), with an integrated flux of f {sub CO(6-5)} = 1004 (± 151) Jy km s{sup –1}. Both the morphology and kinematics of the CO (6-5) emission are rather regular, consistent with a compact rotating disk with a size of 200 pc. A significant emission feature is detected on the redshifted wing of the line profile at the frequency of the H{sup 13}CN (8-7) line, with an integrated flux of 17.7 ± 2.1(random) ± 2.7(systematic) Jy km s{sup –1}. However, it cannot be ruled out that the feature is due to an outflow of warm dense gas with a mean velocity of 400 km s{sup –1}. The continuum is resolved into an elongated configuration, and the observed flux corresponds to a dust mass of M {sub dust} = 10{sup 6.97±0.13} M {sub ☉}. An unresolved central core (radius ≅ 50 pc) contributes 28% of the continuum flux and 19% of the CO (6-5) flux, consistent with insignificant contributions of the AGN to both emissions. Both the CO (6-5) and continuum spatial distributions suggest a very high gas column density (≳ 10{sup 4} M {sub ☉} pc{sup –2}) in the nuclear region at radius ≲ 100 pc.

  14. Integrating a university team in the ALMA software development process: a successful model for distributed collaborations

    NASA Astrophysics Data System (ADS)

    Mora, Matias; Ibsen, Jorge; Chiozzi, Gianluca; Troncoso, Nicolás; Tobar, Rodrigo; Araya, Mauricio; Avarias, Jorge; Hoffstadt, Arturo

    2010-07-01

    Observatories are not all about exciting new technologies and scientific progress. Some time has to be dedicated to the future engineers' generations who are going to be on the front line in a few years from now. Over the past six years, ALMA Computing has been helping to build up and collaborating with a well-organized engineering students' group at Universidad Técnica Federico Santa Maria in Chile. The Computer Systems Research Group (CSRG) currently has wide collaborations with national and international organizations, mainly in the astronomical observations field. The overall coordination and technical work is done primarily by students, working side-by-side with professional engineers. This implies not only using high engineering standards, but also advanced organization techniques. This paper aims to present the way this collaboration has built up an own identity, independently of individuals, starting from its origins: summer internships at international observatories, the open-source community, and the short and busy student's life. The organizational model and collaboration approaches are presented, which have been evolving along with the years and the growth of the group. This model is being adopted by other university groups, and is also catching the attention of other areas inside the ALMA project, as it has produced an interesting training process for astronomical facilities. Many lessons have been learned by all participants in this initiative. The results that have been achieved at this point include a large number of projects, funds sources, publications, collaboration agreements, and a growing history of new engineers, educated under this model.

  15. Disentangling the jet emission from protostellar systems. The ALMA view of VLA1623

    NASA Astrophysics Data System (ADS)

    Santangelo, G.; Murillo, N. M.; Nisini, B.; Codella, C.; Bruderer, S.; Lai, S.-P.; van Dishoeck, E. F.

    2015-09-01

    Context. High-resolution studies of class 0 protostars represent the key to constraining protostar formation models. VLA16234-2417 represents the prototype of class 0 protostars, and it has been recently identified as a triple non-coeval system. Aims: We aim at deriving the physical properties of the jets in VLA16234-2417 using tracers of shocked gas. Methods: ALMA Cycle 0 Early Science observations of CO(2-1) in the extended configuration are presented in comparison with previous SMA CO(3-2) and Herschel-PACS [Oi] 63 μm observations. Gas morphology and kinematics were analysed to constrain the physical structure and origin of the protostellar outflows. Results: We reveal a collimated jet component associated with the [Oi] 63 μm emission at about 8'' (~960 AU) from source B. This newly detected jet component is inversely oriented with respect to the large-scale outflow driven by source A, and it is aligned with compact and fast jet emission very close to source B (about 0''&dotbelow;3) rather than with the direction perpendicular to the A disk. We also detect a cavity-like structure at low projected velocities, which surrounds the [Oi] 63 μm emission and is possibly associated with the outflow driven by source A. Finally, no compact outflow emission is associated with source W. Conclusions: Our high-resolution ALMA observations seem to suggest there is a fast and collimated jet component associated with source B. This scenario would confirm that source B is younger than A, that it is in a very early stage of evolution, and that it drives a faster, more collimated, and more compact jet with respect to the large-scale slower outflow driven by A. However, a different scenario of a precessing jet driven by A cannot be firmly excluded from the present observations. Appendix A is available in electronic form at http://www.aanda.org

  16. ALMA SUBMILLIMETER CONTINUUM IMAGING OF THE HOST GALAXIES OF GRB 021004 AND GRB 080607

    SciTech Connect

    Wang, Wei-Hao; Huang, Kui-Yun; Chen, Hsiao-Wen

    2012-12-20

    We report 345 GHz continuum observations of the host galaxies of gamma-ray bursts (GRBs) 021004 and 080607 at z > 2 using the Atacama Large Millimeter/Submillimeter Array (ALMA) in Cycle 0. Of the two bursts, GRB 021004 is one of the few GRBs that originate in a Lyman limit host, while GRB 080607 is classified as a 'dark burst' and its host galaxy is a candidate of dusty star-forming galaxy at z {approx} 3. With an order of magnitude improvement in the sensitivities of the new imaging searches, we detect the host galaxy of GRB 080607 with a flux of S{sub 345} = 0.31 {+-} 0.09 mJy and a corresponding infrared luminosity of L{sub IR} = (2.4-4.5) Multiplication-Sign 10{sup 11} L{sub Sun }. However, the host galaxy of GRB 021004 remains undetected and the ALMA observations allow us to place a 3{sigma} upper limit of L{sub IR} < 3.1 Multiplication-Sign 10{sup 11} L{sub Sun} for the host galaxy. The continuum imaging observations show that the two galaxies are not ultraluminous infrared galaxies, but are at the faintest end of the dusty galaxy population that gives rise to the submillimeter extragalactic background light. The derived star formation rates of the two GRB host galaxies are less than 100 M{sub Sun} yr{sup -1}, which are broadly consistent with optical measurements. The result suggests that the large extinction (A{sub V} {approx} 3) in the afterglow of GRB 080607 is confined along its particularly dusty sight line, and not representative of the global properties of the host galaxy.

  17. Spectral and morphological analysis of the remnant of supernova 1987A with ALMA and ATCA

    SciTech Connect

    Zanardo, Giovanna; Staveley-Smith, Lister; Indebetouw, Remy; Chevalier, Roger A.; Matsuura, Mikako; Barlow, Michael J.; Gaensler, Bryan M.; Fransson, Claes; Lundqvist, Peter; Manchester, Richard N.; Baes, Maarten; Kamenetzky, Julia R.; Lakićević, Maša; Marcaide, Jon M.; Meixner, Margaret; Ng, C.-Y.; Park, Sangwook; and others

    2014-12-01

    We present a comprehensive spectral and morphological analysis of the remnant of supernova (SN) 1987A with the Australia Telescope Compact Array (ATCA) and the Atacama Large Millimeter/submillimeter Array (ALMA). The non-thermal and thermal components of the radio emission are investigated in images from 94 to 672 GHz (λ 3.2 mm to 450 μm), with the assistance of a high-resolution 44 GHz synchrotron template from the ATCA, and a dust template from ALMA observations at 672 GHz. An analysis of the emission distribution over the equatorial ring in images from 44 to 345 GHz highlights a gradual decrease of the east-to-west asymmetry ratio with frequency. We attribute this to the shorter synchrotron lifetime at high frequencies. Across the transition from radio to far infrared, both the synchrotron/dust-subtracted images and the spectral energy distribution (SED) suggest additional emission beside the main synchrotron component (S {sub ν}∝ν{sup –0.73}) and the thermal component originating from dust grains at T ∼ 22 K. This excess could be due to free-free flux or emission from grains of colder dust. However, a second flat-spectrum synchrotron component appears to better fit the SED, implying that the emission could be attributed to a pulsar wind nebula (PWN). The residual emission is mainly localized west of the SN site, as the spectral analysis yields –0.4 ≲ α ≲ –0.1 across the western regions, with α ∼ 0 around the central region. If there is a PWN in the remnant interior, these data suggest that the pulsar may be offset westward from the SN position.

  18. ALMA DETECTED OVERDENSITY OF SUB-MILLIMETER SOURCES AROUND WISE/NVSS-SELECTED z ∼ 2 DUSTY QUASARS

    SciTech Connect

    Silva, Andrea; Sajina, Anna; Lonsdale, Carol; Lacy, Mark

    2015-06-20

    We study the environments of 49 WISE/NVSS-selected dusty, hyper-luminous, z ∼ 2 quasars using the Atacama Large Millimeter/Sub-millimeter Array (ALMA) 345 GHz images. We find that 17 of the 49 WISE/NVSS sources show additional sub-millimeter galaxies within the ALMA primary beam, probing scales within ∼150 kpc. We find a total of 23 additional sub-millimeter sources, four of which are in the field of a single WISE/NVSS source. The measured 870 μm source counts are ∼10× what is expected for unbiased regions, suggesting such hyper-luminous dusty quasars are excellent at probing high-density peaks.

  19. VizieR Online Data Catalog: ALMA 870um obs. of HerMES galaxies (Bussmann+, 2015)

    NASA Astrophysics Data System (ADS)

    Bussmann, R. S.; Riechers, D.; Fialkov, A.; Scudder, J.; Hayward, C. C.; Cowley, W. I.; Bock, J.; Calanog, J.; Chapman, S. C.; Cooray, A.; de Bernardis, F.; Farrah, D.; Fu, H.; Gavazzi, R.; Hopwood, R.; Ivison, R. J.; Jarvis, M.; Lacey, C.; Loeb, A.; Oliver, S. J.; Perez-Fournon, I.; Rigopoulou, D.; Roseboom, I. G.; Scott, D.; Smith, A. J.; Vieira, J. D.; Wang, L.; Wardlow, J.

    2016-02-01

    ALMA 870um data were obtained during Cycle 0 from 2012 June to December (Program 2011.0.00539.S; PI: D. Riechers). Optical imaging observations (ugriz) using the Gemini Multi-Object Spectrograph-South (GMOS-S) were conducted in queue mode during the 2013B semester as part of program GS-2013B-Q-77 (PI: R. S. Bussmann). (3 data files).

  20. VizieR Online Data Catalog: Faint ALMA 1.2mm sources down to ~0.02mJy (Fujimoto+, 2016)

    NASA Astrophysics Data System (ADS)

    Fujimoto, S.; Ouchi, M.; Ono, Y.; Shibuya, T.; Ishigaki, M.; Nagai, H.; Momose, R.

    2016-06-01

    We use 67 continuum maps obtained by ~120 pointing of the ALMA cycle 0-2 observations in Band 6/7 that accomplish high sensitivities and angular resolutions. For the mapping mode definitions, there are maps targeting field regions by single-pointing observations, referred to as "field" data, 4 and 62 out of which are taken from our programs and the ALMA archive, respectively. Two out of the four maps were taken in the ALMA cycle-0 Band 6 observations for the spectroscopically confirmed Lyα emitter (LAE) at z=6.595 (Himiko) and an LAE at z=6.511 (NB921-N-79144). See Ono et al. (2014ApJ...795....5O) for a summary of these observations. We also utilize two maps of newly obtained (ALMA cycle 2) field data of Bands 6 and 7 taken for spectroscopically confirmed LAEs at z=5.7 (NB816-S-61269) and at z=7.3 (NB101-S-2904). The NB816-S-61269 observations were carried out in the ALMA program of #2012.1.00602.S (PI: R. Momose) on 2014 May 20, Jun 19, and July 7 with 43 12m antennae array in the range of 18-650m baseline. The NB101-S-2904 data were taken in the ALMA program of #2012.1.00088.S (PI: M. Ouchi) on 2014 July 22 and August 6, 7, 14, and 18, with 55 12m antennae array in the extended configuration of 18-1300m baseline. See section 2.1 for further explanations. To increase the number of ALMA sources, we make full use of ALMA archival data of cycles 0 and 1 that became public by 2015 June. See references in table2 for the collected 62 maps and section 2.2.1 for further details. One-cluster data were taken for Abell 1689 (A1689) in ALMA cycle 0 and 1 observations (PI: J. Richard) of ALMA #2011.0.00319.S and #2012.1.00261.S (see section 2.2.2 for further explanations). (3 data files).

  1. Revealing a Detailed Mass Distribution of a High-density Core MC27/L1521F in Taurus with ALMA

    NASA Astrophysics Data System (ADS)

    Tokuda, Kazuki; Onishi, Toshikazu; Matsumoto, Tomoaki; Saigo, Kazuya; Kawamura, Akiko; Fukui, Yasuo; Inutsuka, Shu-ichiro; Machida, Masahiro N.; Tomida, Kengo; Tachihara, Kengo; André, Philippe

    2016-07-01

    We present the results of ALMA observations of dust continuum emission and molecular rotational lines toward a dense core MC27 (aka L1521F) in Taurus, which is considered to be at a very early stage of star formation. The detailed column density distributions on size scales from a few tens to ˜10,000 AU are revealed by combining the ALMA (12 m array + 7 m array) data with the published/unpublished single-dish data. The high angular resolution observations at 0.87 mm with a synthesized beam size of ˜0.″74 × 0.″32 reveal that a protostellar source, MMS-1, is not spatially resolved and lacks associated gas emission, while a starless high-density core, MMS-2, has substructures in both dust and molecular emission. The averaged radial column density distribution of the inner part of MC27/L1521F (r ≲ 3000 AU) is {N}{{{H}}2} ˜ {r}-0.4, clearly flatter than that of the outer part, ˜{r}-1.0. The complex velocity/spatial structure obtained with previous ALMA observations is located inside the inner flatter region, which may reflect the dynamical status of the dense core.

  2. ALMA-SZ Detection of a Galaxy Cluster Merger Shock at Half the Age of the Universe

    NASA Astrophysics Data System (ADS)

    Basu, K.; Sommer, M.; Erler, J.; Eckert, D.; Vazza, F.; Magnelli, B.; Bertoldi, F.; Tozzi, P.

    2016-10-01

    We present ALMA measurements of a merger shock using the thermal Sunyaev-Zel’dovich (SZ) effect signal, at the location of a radio relic in the famous El Gordo galaxy cluster at z≈ 0.9. Multi-wavelength analysis in combination with the archival Chandra data and a high-resolution radio image provides a consistent picture of the thermal and non-thermal signal variation across the shock front and helps to put robust constraints on the shock Mach number as well as the relic magnetic field. We employ a Bayesian analysis technique for modeling the SZ and X-ray data self-consistently, illustrating respective parameter degeneracies. Combined results indicate a shock with Mach number { M }={2.4}-0.6+1.3, which in turn suggests a high value of the magnetic field (of the order of 4-10 μ {{G}}) to account for the observed relic width at 2 GHz. At roughly half the current age of the universe, this is the highest-redshift direct detection of a cluster shock to date, and one of the first instances of an ALMA-SZ observation in a galaxy cluster. It shows the tremendous potential for future ALMA-SZ observations to detect merger shocks and other cluster substructures out to the highest redshifts.

  3. Terahertz Desorption Emission Spectroscopy (THz DES) - ‘ALMA in the Lab’

    NASA Astrophysics Data System (ADS)

    Emile Auriacombe, Olivier Bruno Jacques; Fraser, Helen; Ellison, Brian; Ioppolo, Sergio; Rea, Simon

    2016-06-01

    ALMA is revolutionising our scope to identify and locate molecules that have been desorbed from ices, particularly complex organic molecules (COMS), which provide a vital link between interstellar and prebiotic chemistry. Explaining the existence of these molecules in star-forming regions relies on an empirical understanding of the chemistry that underpins their formation:- do COMS form predominantly in the solid-phase and then desorb to the gas phase, or do only “smaller” species, radials or ions desorb and then undergo gas-phase chemical reactions to generate larger COMS?-are the rotational state populations in COMS only attributable to equilibrium chemistry, or could their formation mechanisms and desorption processes affect the rotational state occupancy of these molecules, thereby directly tying certain species to solid-state origins?We have developed a novel laboratory method - THz Desorption Emission Spectroscopy (THz-DES) that combines “traditional” laboratory astrophysics high-vacuum ice experiments with a sensitive high-spectral-resolution terahertz total-power heterodyne radiometer 1,2, partially mirroring the spectral range of ALMA band 7 (275- 373 GHz). Ices are grown in situ on a cold-plate, situated in a vacuum cell, then (thermally) desorbed. The sub-mm emission spectra of the resultant gas-phase molecules are detected as a function of time, temperature, or distance from the surface. Our first THz DES results will be shown for pure and binary ice systems including H2O, N2O and CH3OH. They show good correlation with established methods e.g. TPD, with the advantage of exploiting the molecular spectroscopy to unravel surface dynamics, state-occupancy, and unequivocal molecular identification, as well as concurrently measuring desorption barriers and molecular yields. We will extend our technique to a broader frequency range, enabling us to detect radical and ion desorption, to differentiate between A and E populations of CH3OH or ortho

  4. Thermal structure and minor species distribution of Venus mesosphere by ALMA submm observations

    NASA Astrophysics Data System (ADS)

    Piccialli, Arianna; Moreno, Raphael; Encrenaz, Therese; Fouchet, Thierry; Lellouch, Emmanuel; Moullet, Arielle; Widemann, Thomas

    2015-11-01

    Venus upper atmosphere (70-150 km altitude) is a transition region characterized by a complex dynamics: strong retrograde zonal winds dominate the lower mesosphere while a solar-to-antisolar circulation is observed in the upper mesosphere/lower thermosphere. In addition, photochemical processes play an important role at these altitudes and affect the thermal structure and chemical stability of the entire atmosphere. Sulfur dioxide and water vapor are key species in the photochemical cycles taking place in the troposphere and mesosphere of Venus. They are carried by convective transport, together with the Hadley circulation, up to about 60 km where SO2 is photodissociated and oxydated, leading to the formation of H2SO4 which condenses in the clouds enshrouding the planet. Previous observations obtained by several instruments on board Venus Express and during ground-based campaigns have shown evidence of strong temporal variations, both on day-to-day as well as longer timescales, of density, temperature and SO2 abundance. Such strong variability is still not well understood.Submillimeter observations obtained with the Atacama Large Millimeter Array (ALMA) offer the possibility of probing Venus upper mesosphere and of monitoring minor species, winds and the thermal structure. A first set of observations was obtained on November 14, 15, 26 and 27, 2011 during the first ALMA Early Science observation cycle. These observations targeted SO2, SO, HDO and CO transitions around 345 GHz during four sequences of 30 minutes each. The Venus’ disk was about 11” with an illumination factor of 90%, so that mostly the dayside of the planet was mapped.Assuming nominal night-time and dayside CO abundance profiles from Clancy et al. 2013, we retrieved vertical temperature profiles over the entire disk as a function of latitude and local time for the four days of observation. Temperature profiles were later used to derive the abundances of minor species (HDO, SO, SO2) in each pixel

  5. Terahertz Desorption Emission Spectroscopy (THz DES) – ‘ALMA in the Lab’

    NASA Astrophysics Data System (ADS)

    Emile Auriacombe, Olivier Bruno Jacques; Fraser, Helen; Ellison, Brian; Ioppolo, Sergio; Rea, Simon

    2016-06-01

    ALMA is revolutionising our scope to identify and locate molecules that have been desorbed from ices, particularly complex organic molecules (COMS), which provide a vital link between interstellar and prebiotic chemistry. Explaining the existence of these molecules in star-forming regions relies on an empirical understanding of the chemistry that underpins their formation:- do COMS form predominantly in the solid-phase and then desorb to the gas phase, or do only “smaller” species, radials or ions desorb and then undergo gas-phase chemical reactions to generate larger COMS?-are the rotational state populations in COMS only attributable to equilibrium chemistry, or could their formation mechanisms and desorption processes affect the rotational state occupancy of these molecules, thereby directly tying certain species to solid-state origins?We have developed a novel laboratory method - THz Desorption Emission Spectroscopy (THz-DES) that combines “traditional” laboratory astrophysics high-vacuum ice experiments with a sensitive high-spectral-resolution terahertz total-power heterodyne radiometer 1,2, partially mirroring the spectral range of ALMA band 7 (275– 373 GHz). Ices are grown in situ on a cold-plate, situated in a vacuum cell, then (thermally) desorbed. The sub-mm emission spectra of the resultant gas-phase molecules are detected as a function of time, temperature, or distance from the surface. Our first THz DES results will be shown for pure and binary ice systems including H2O, N2O and CH3OH. They show good correlation with established methods e.g. TPD, with the advantage of exploiting the molecular spectroscopy to unravel surface dynamics, state-occupancy, and unequivocal molecular identification, as well as concurrently measuring desorption barriers and molecular yields. We will extend our technique to a broader frequency range, enabling us to detect radical and ion desorption, to differentiate between A and E populations of CH3OH or ortho

  6. Morphology of Midlatitude Summer Nighttime Anomaly in NmF2 above Alma-Ata

    NASA Astrophysics Data System (ADS)

    Yakovets, Artur; Gordienko, Galina; Litvinov, Yuriy

    2016-04-01

    The morphology of the midlatitude summer nighttime anomaly in the diurnal behavior of the electron concentration maximum in the F2 layer (NmF2) over Alma-Ata in various seasons and at various solar activity levels was studied on the basis of the ionospheric vertical sounding over seven months of 2011 and the summer months of 1999, 2008, 2011, and 2012. The vast majority of data of the analyzed electron concentration measurements was obtained under low magnetic activity (Dst > -50 nT). Measurements during which moderate and high magnetic activity (Dst < -50 nT) was observed were rejected from the analysis. It was shown that the anomaly is not seen in the equinox months. The maximum effect of the anomaly is seen in the summer months (July-August). The maximum value of the electron concentration in the evening peak corresponds to the solar zenith angles, when the ionizing radiation almost ceases to reach the heights of the F2 layer maximum. The anomaly is distinctly manifested in the solar activity minimum but scarcely seen in the solar maximum. It was shown that the parameters of the summer anomaly at the boundary of the north-eastern Asia zone (Alma-Ata, 76.9 deg E) change insignificantly as compared to the parameters at its center (Japan, 130.0 deg E). The mechanisms of the formation of the anomaly and of its diurnal and seasonal behavior are discussed. Two factors determining the anomaly formation in the summer months are considered. First, the meridional wind changes its direction from polarward to equatorqard much earlier in summer (around 14.30 LT) in the middle latitudes than in other seasons, when the photoionizing radiation flux is still high. That is why photoionization, in combination with the rise of the ionosphere to the heights where the recombination rate is low, leads to the formation of an evening increase in NmF2. Second, in addition to the factor of an early change in the thermospheric wind direction, seasonal variations in the meridional wind

  7. Modeling the thermal emission from asteroid 3 Juno using ALMA observations and the KRC thermal model

    NASA Astrophysics Data System (ADS)

    Titus, Timothy N.; Li, Jian-Yang; Moullet, Arielle; Sykes, Mark V.

    2015-11-01

    Asteroid 3 Juno (hereafter referred to as Juno), discovered 1 September 1804, is the 11th largest asteroid in the Main Asteroid Belt (MAB). Containing approximately 1% of the mass in the MAB [1], Juno is the second largest S-type [2].As part of the observations acquired from Atacama Large Millimeter/submillimeter Array (ALMA) [3], 10 reconstructed images at ~60km/pixel resolution were acquired of Juno [4] that showed significant deviations from the Standard Thermal Model (STM) [5]. These deviations could be a result of surface topography, albedo variations, emissivity variations, thermal inertia variations, or any combination.The KRC thermal model [6, 7], which has been extensively used for Mars [e.g. 8, 9] and has been applied to Vesta [10] and Ceres [11], will be used to compare model thermal emission to that observed by ALMA at a wavelength of 1.33 mm [4]. The 10 images, acquired over a four hour period, captured ~55% of Juno’s 7.21 hour rotation. Variations in temperature as a function of local time will be used to constrain the source of the thermal emission deviations from the STM.This work is supported by the NASA Solar System Observations Program.References:[1] Pitjeva, E. V. (2005) Solar System Research 39(3), 176. [2] Baer, J. and S. R. Chesley (2008) Celestial Mechanics and Dynamical Astronomy, 100, 27-42. [3] Wootten A. et al. (2015) IAU General Assembly, Meeting #29, #2237199 [4] arXiv:1503.02650 [astro-ph.EP] doi: 10.1088/2041-8205/808/1/L2 [5] Lebofsky, L.A. eta al. (1986) Icarus, 68, 239-251. [6] Kieffer, H. H., et al. (1977) J. Geophys. Res., 82, 4249-4291. [7] Kieffer, Hugh H., (2013) Journal of Geophysical Research: Planets, Volume 118, Issue 3, pp. 451-470 [8] Titus, T. N., H. H. Kieffer, and P. N. Christensen (2003) Science, 299, 1048-1051. [9] Fergason, R. L. et al. (2012) Space Sci. Rev, 170, 739-773, doi:10.1007/s11214-012-9891-3. [10] Titus, T. N. et al. (2012) 43rd LPSC, held March 19-23, 2012 at The Woodlands, Texas. LPI Contribution No

  8. The Cologne Database for Molecular Spectroscopy, Cdms, in Times of Herschel, SOFIA, and Alma

    NASA Astrophysics Data System (ADS)

    Müller, Holger S. P.; Stutzki, Jürgen; Schlemmer, Stephan

    2009-06-01

    The CDMS provides in its catalog section atomic and molecular line lists for species that have been or may be observed in space by radio astronomical means. The line list of each molecule is gathered in an individual entry; minor isotopologs have separate entries, and the same applies to excited vibrational states with the exception of some diatomic molecules. With 5 to 10 new or updated entries each month, the CDMS catalog has been growing rapidly over the past 10 years: since February 2009, there have been more than 500 entries in the CDMS - with many more entries to be created. Entries are generated from fitting (mostly) laboratory data to accepted Hamiltonian models. Despite many dedicated laboratory spectroscopic investigations in recent years, accurate data is still lacking frequently - in particular at higher frequencies, for minor isotopic species, for excited vibrational states, or for somewhat larger molecules. While high frequency data are of special concern for the Herschel satellite, scheduled to be launched in mid-April 2009, or for the Stratospheric Observatory For Infrared Astronomy (SOFIA), the remaining issues mentioned above are important especially for telecope arrays such as the Atacama Large Millimeter Array (ALMA). The main features of the CDMS catalog will be described, including recent developments concerning new entries as well as available and planned features. In particular, we will discuss issues relevant for generating a consolidated database that also takes into account information from other databases. Attention will be given to laboratory spectroscopic needs for missions such as Herschel and SOFIA on one hand and for ALMA, the Expanded Very Large Array (EVLA), and other facilities on the other, both, in terms of general aspects and in terms of specific examples. Selected contributions from the Cologne spectroscopy laboratories to address these needs will be presented. H. S. P. Müller, S. Thorwirth, D. A. Roth, G. Winnewisser

  9. Thermal mapping of Ceres at 1.2 mm with ALMA

    NASA Astrophysics Data System (ADS)

    Moullet, Arielle; Li, Jian-Yang; Titus, Timothy N.; Sykes, Mark V.; Ip, Wing-Huen; Lai, Ian-Lin

    2016-10-01

    Ceres' thermal emission distribution, which can be characterized through observations at IR and longer wavelengths, is indicative of radiative and physical properties of its surface such as thermal inertia and roughness. High-resolution maps from the Dawn mission now provide an exquisite geographic and geological context for the interpretation of temperature features, which are at large not accessible to the spacecraft's instruments. In particular, the presence of hydrated minerals and distinctive geological features suggest the existence of ice water reservoirs near the surface, which may be characterized through the analysis of thermal inertia distributions.We report on observations obtained in Fall 2015 at the Atacama Large Millimeter Array (ALMA), sampling most of the rotation of Ceres and hence allowing one to disentangle local-hour effects from geographical thermal features. The observations were performed during the 2015 Long Baseline Campaign, offering baselines as long as 10 km and yielding a spatial resolution down to 30 mas (~45 km at the equator). At the observed wavelength of 1.2 mm, the thermal emission probes both the emission from the surface and from deeper layers, down to the level of the diurnal skin depth, hence accessing regions where water ice could be stable.We will describe the diurnal and latitudinal temperature variations derived from our observations as well as preliminary results from thermal modeling in terms of subsurface thermal inertia and ice table latitudinal extent. This work is supported by the NASA Solar System Observations Program grant NNX15AE02G.

  10. ALMA Imaging of HCN, CS, and Dust in Arp 220 and NGC 6240

    NASA Astrophysics Data System (ADS)

    Scoville, Nick; Sheth, Kartik; Walter, Fabian; Manohar, Swarnima; Zschaechner, Laura; Yun, Min; Koda, Jin; Sanders, David; Murchikova, Lena; Thompson, Todd; Robertson, Brant; Genzel, Reinhard; Hernquist, Lars; Tacconi, Linda; Brown, Robert; Narayanan, Desika; Hayward, Christopher C.; Barnes, Joshua; Kartaltepe, Jeyhan; Davies, Richard; van der Werf, Paul; Fomalont, Edward

    2015-02-01

    We report ALMA Band 7 (350 GHz) imaging at 0.''4-0.''6 resolution and Band 9 (696 GHz) at ~0.''25 resolution of the luminous IR galaxies Arp 220 and NGC 6240. The long wavelength dust continuum is used to estimate interstellar medium masses for Arp 220 east and west and NGC 6240 of 1.9, 4.2, and 1.6 × 109 M ⊙within radii of 69, 65, and 190 pc. The HCN emission was modeled to derive the emissivity distribution as a function of radius and the kinematics of each nuclear disk, yielding dynamical masses consistent with the masses and sizes derived from the dust emission. In Arp 220, the major dust and gas concentrations are at radii less than 50 pc in both counter-rotating nuclear disks. The thickness of the disks in Arp 220 estimated from the velocity dispersion and rotation velocities are 10-20 pc and the mean gas densities are nH_2 ˜ 10^5 cm-3 at R <50 pc. We develop an analytic treatment for the molecular excitation (including photon trapping), yielding volume densities for both the HCN and CS emission with n H2 ~ 2 × 105 cm-3. The agreement of the mean density from the total mass and size with that required for excitation suggests that the volume is essentially filled with dense gas, i.e., it is not cloudy or like swiss cheese.

  11. Revised spectroscopic parameters of SH(+) from ALMA and IRAM 30m observations.

    PubMed

    Müller, Holger S P; Goicoechea, Javier R; Cernicharo, José; Agúndez, Marcelino; Pety, Jérôme; Cuadrado, Sara; Gerin, Maryvonne; Dumas, Gaëlle; Chapillon, Edwige

    2014-09-19

    Hydrides represent the first steps of interstellar chemistry. Sulfanylium (SH(+)), in particular, is a key tracer of energetic processes. We used ALMA and the IRAM 30 m telescope to search for the lowest frequency rotational lines of SH(+) toward the Orion Bar, the prototypical photo-dissociation region illuminated by a strong UV radiation field. On the basis of previous Herschel/HIFI observations of SH(+), we expected to detect emission of the two SH(+) hyperfine structure (HFS) components of the NJ = 10-01 fine structure (FS) component near 346 GHz. While we did not observe any lines at the frequencies predicted from laboratory data, we detected two emission lines, each ~15 MHz above the SH(+) predictions and with relative intensities and HFS splitting expected for SH(+). The rest frequencies of the two newly detected lines are more compatible with the remainder of the SH(+) laboratory data than the single line measured in the laboratory near 346 GHz and previously attributed to SH(+). Therefore, we assign these new features to the two SH(+) HFS components of the NJ = 10-01 FS component and re-determine its spectroscopic parameters, which will be useful for future observations of SH(+), in particular if its lowest frequency FS components are studied. Our observations demonstrate the suitability of these lines for SH(+) searches at frequencies easily accessible from the ground.

  12. Observing the Hyperfine 3.06mm Line Of Iron-57 With ALMA

    NASA Astrophysics Data System (ADS)

    Chatzikos, Marios; Ferland, G. J.; Williams, R.; Fabian, A.

    2013-01-01

    The central regions of galaxy clusters are known to harbor a large reservoir of near-solar metallicity gas. In this work, we investigate the predictions of Sunyaev & Churazov (1984) and D'Cruz, Sarazin & Dubau (1998; DSD98) that the 3.06mm hyperfine structure line of iron-57 may be observable in the gaseous atmospheres of galaxy clusters. Because iron-57 is produced through different nuclear reaction channels in supernovae type Ia and II, the relative abundance of this isotope with respect to iron-56 is expected to shed some light into the different supernova rates that occur in galaxy clusters. To this end, we have expanded the work of DSD98 to include indirect excitations of the more energetic hyperfine state through cascades from higher atomic levels than 2p, "optical pumping" by X-rays from the central AGN, and the effects of the radio synchrotron continuum. We implement these calculations by adapting the spectral simulation code CLOUDY (Ferland et al. 1998). We discuss the observability of the hyperfine line with ALMA for the Perseus cluster.

  13. Galactic center mini-spiral by ALMA: Possible origin of the central cluster

    NASA Astrophysics Data System (ADS)

    Tsuboi, Masato; Kitamura, Yoshimi; Miyoshi, Makoto; Uehara, Kenta; Tsutsumi, Takahiro; Miyazaki, Atsushi

    2016-06-01

    We present continuum images of the "Galactic center mini-spiral" in the 100, 250, and 340 GHz bands with analysis of the Cy.0 data acquired from the Atacama Large Millimeter/submillimeter Array (ALMA) archive. Good u-v coverage of the data and the "self-calibration" method give us the opportunity to obtain dynamic ranges of over 2 × 104 in the resultant maps of the 250 and 340 GHz bands. In particular, the image of the 340 GHz band has high dynamic ranges unprecedented in sub-millimeter waves. The angular resolutions attained are 1{^''.}57 × 1{^''.}33 in the 100 GHz band, 0{^''.}63 × 0{^''.}53 in the 250 GHz band, and 0{^''.}44 × 0{^''.}38 in the 340 GHz band, respectively. The continuum images clearly depict the "mini-spiral," which is an ionized gas stream in the vicinity of Sgr A*. We found a tight correlation between the dust emission peaks and the OB/WR stars in the northern arm of the "mini-spiral." The core mass function of the dust cores identified by the clumpfind algorithm would obey the flat power-law dN/dM ∝ M-1.5±0.4 on the high-mass side. These support the scenario that the star-forming cloud has fallen into the immediate vicinity of Sgr A* for the origin of the central cluster.

  14. Three-dimensional mapping of the water cycle and D/H on Mars with ALMA

    NASA Astrophysics Data System (ADS)

    Villanueva, Geronimo Luis; Mumma, Michael J.; Novak, Robert E.; Gurwell, Mark A.; Clarke, John T.; Tokunaga, Alan T.; Khayat, Alain; Hecht, Michael; Fisher, David Andrew

    2016-10-01

    Using ALMA, we mapped the vertical distribution of the water D/H across a broad range of terrains and times of days and local seasons on Mars. The observations were done in March/2016 and targeted four lines of isotopic water (H2O, HDO, H218O, H217O), and one line of isotopic carbon monoxide (C17O) used for establishing the thermal structure. The observations allowed us to investigate and separate how the D/H evolves on the planet, since fractionation processes induced by cloud formation would lead to notable variations of D/H along the column.Isotopic measurements are per-se excellent tracers of water loss/evolution on Mars (Villanueva et al. 2015), yet some of the recently observed variations are striking and reveal a far more complex scenario for the processes acting on the Martian water cycle. They are perhaps indicative of sub-surface water reservoirs interacting with the atmosphere, but the IR measurements did not resolve the vertical structure, limiting the untangling of climatological effects (e.g., cloud formation, Rayleigh distillation).We will present 3D maps of water and D/H and will discuss possible scenarios to explain the observations, in particular, in the context of the upper-atmosphere D/H MAVEN measurements.Villanueva, G. L., Mumma, M. J., Novak, R. E., et al. 2015, Science, 348, 218

  15. Planetary Radio Astronomy: The 60 Years from Burke and Franklin to ALMA

    NASA Astrophysics Data System (ADS)

    Steffes, Paul G.

    2014-11-01

    For nearly 60 years, radio astronomy has played a major role in the characterization and monitoring of thermal structure, composition, and temporal changes of the planets and small bodies in our solar system. At this, the 60th anniversary of the initial detection of radio emission by a planet, the role radio astronomy has played in the early characterization of solar system objects, in raising basic scientific questions and motivating planetary exploration missions, and in providing insight into the structure and temporal variations of planets is explored. The evolution of the instrumentation capabilities from crude total-power, or bolometric measurements averaged over an entire planetary disk to today's instrumentation providing radio images of planets and comets with high spectral resolution is also discussed. Major developments such as precise total-power calibration, ultra-large apertures, microwave and millimeter-wave array technology, and supporting laboratory spectroscopy have played major roles in enhancing the effectiveness of radio astronomical observations. The newest generation instruments such as the upgraded Jansky Very Large Array (VLA) and the Altacama Large Millimeter Array (ALMA) now usher in a whole new level of capability in observation of solar system objects.

  16. Investigating star formation properties of galaxies in massive clusters with Herschel and ALMA

    NASA Astrophysics Data System (ADS)

    Wu, John F.; Baker, Andrew J.; Aguirre, Paula; Barkats, D.; Halpern, Mark; Hilton, Matt; Hughes, John Patrick; Infante, Leopoldo; Lindner, Robert; Marriage, Tobias; Menanteau, Felipe; Sifon, Cristobal; Weiss, Axel; ACT Collaboration

    2016-01-01

    I will present results from an investigation of star formation properties of galaxies residing in two massive z ~ 1 clusters (including the 'El Gordo' merger) that were initially selected via their Sunyaev-Zeldovich decrements by the Atacama Cosmology Telescope (ACT) southern survey. This study uses new Herschel Space Observatory and Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 2 observations, which provide information about the dust and cold gas content of galaxies in our targeted clusters. We have detected CO (4-3) and [CI] in individual star-forming cluster galaxies, and also measured stacked continuum and spectral line fluxes at long (e.g., far-infrared, submillimeter, and radio) wavelengths. We use these results to explore the relations between star formation and local environment and cluster dynamical state.This work has been supported by (i) an award issued by JPL/Caltech in association with Herschel, which is a European Space Agency Cornerstone Mission with significant participation by NASA, and (ii) the National Science Foundation through award GSSP SOSPA2-018 from the National Radio Astronomy Observatory, which is operated under cooperative agreement by Associated Universities, Inc.

  17. GRB110715A: Multifrequency study of the first gamma-ray burst observed with ALMA

    NASA Astrophysics Data System (ADS)

    Sánchez-Ramírez, R.; de Ugarte Postigo, A.; Gorosabel, J.; Hankcock, P.; Murphy, T.; Lundgren, A.; Kann, D. A.; de Gregorio Monsalvo, I.; Fynbo, J. P. U.; Garcia-Appadoo, D.; Martín, S.; Kamble, A.; Kuin, M. P. M.; Oates, S. R.; Castro-Tirado, A. J.; Greiner, J.

    2013-05-01

    GRB 110715A had a bright afterglow that was obscured by a high Galactic extinction. We discovered the submillimetre counterpart with APEX and followed it in radio with ATCA for over 2 months. Additional submillimetre observations were performed with ALMA as a test of the ToO procedures during commissioning. UV, optical and NIR observations were performed with UVOT/Swift and GROND at the 2.2 m telescope in La Silla and X-ray data was obtained by XRT/Swift. The dataset is complemented with spectroscopic data from the X-shooter spectrograph at the VLT. From a broadband model we derive a peculiar density profile in the environment of the progenitor, with a discontinuity that produces a break in the light curve at ˜1 day after the burst onset. The absorption features present in the intermediate resolution optical/nIR spectra reveal a redshift of 0.8224 and a host galaxy environment with low ionisation and no velocity components beyond 30 km s^{-1}. These preliminary results will be published elsewhere Sanchez-Ramirez et al. (in preparation).

  18. AN ALMA DISK MASS FOR THE CANDIDATE PROTOPLANETARY COMPANION TO FW TAU

    SciTech Connect

    Kraus, Adam L.; Andrews, Sean M.; Bowler, Brendan P.; Herczeg, Gregory; Ireland, Michael J.; Liu, Michael C.; Metchev, Stanimir; Cruz, Kelle L.

    2015-01-01

    We present ALMA observations of the FW Tau system, a close binary pair of M5 stars with a wide-orbit (300 AU projected separation) substellar companion. The companion is extremely faint and red in the optical and near-infrared, but boasts a weak far-infrared excess and optical/near-infrared emission lines indicative of a primordial accretion disk of gas and dust. The component-resolved 1.3 mm continuum emission is found to be associated only with the companion, with a flux (1.78 ± 0.03 mJy) that indicates a dust mass of 1-2 M {sub ⊕}. While this mass reservoir is insufficient to form a giant planet, it is more than sufficient to produce an analog of the Kepler-42 exoplanetary system or the Galilean satellites. The mass and geometry of the disk-bearing FW Tau companion remains unclear. Near-infrared spectroscopy shows deep water bands that indicate a spectral type later than M5, but substantial veiling prevents a more accurate determination of the effective temperature (and hence mass). Both a disk-bearing ''planetary-mass'' companion seen in direct light or a brown dwarf tertiary viewed in light scattered by an edge-on disk or envelope remain possibilities.

  19. SMA and ALMA Studies of Protoplanetary-Disk Formation around Low-mass Protostars

    NASA Astrophysics Data System (ADS)

    Takakuwa, Shigehisa; Yen, Hsi-Wei; Ohashi, Nagayoshi; Chou, Ti-Lin; Aso, Yusuke; Saigo, Kazuya; Saito, Masao; Machida, Masahiro N.; Tomida, Kengo; Aikawa, Yuri; Tomisaka, Kohji; Koyamatsu, Shin; Takahashi, Sanemichi Z.

    2015-08-01

    In this presentation, we will report our systematic observational studies of protoplanetary-disk formation around low-mass protostars with the SMA and ALMA. We have identified five Class 0-I protostellar systems (L1551 IRS 5, L1551 NE, L1489 IRS, L1527 IRS, and TMC-1A) associated with the r~100 - 300 AU scale Keplerian disks and the outer infalling envelopes. The infalling velocities of the envelope gas onto the Keplerian disks are found to be a factor ~3 smaller than the free-fall velocities of the central protostellar masses inferred from the inner Keplerian rotation. On the other hand, the rotational angular momenta in the infalling envelopes appear to smoothly connect to those of the inner Keplerian disks. Including the other disk sources found by previous observations, we have also found a growth of the disk radii as a function of the protostellar evolution. These results demonstrate how the central Keplerian disks around protostars, precursors of the protoplanetary disks, grow and evolve. We will compile these observational results in the context of an unified picture of protoplanetary-disk formation, and compare them to the latest theoretical predictions of protoplanetary-disk formation.

  20. Preliminary Work to Alma: Submillimeter Wave Spectroscopy of ^{18}O and D Species of Methyl Formate

    NASA Astrophysics Data System (ADS)

    Margulès, L.; Motiyenko, R.; Huet, T. R.; Møllendal, H.; Guillemin, J.-C.; Demyk, K.; Carvajal, M.; Kleiner, I.; Coudert, L. H.

    2009-06-01

    New radiotelescopes, working in the submillimeter range, will be operating in the next few years: ALMA, Herschel, and SOFIA. A large amount of laboratory work is required in order to account for the increased resolution and accuracy needed to analyze the numerous data which will be obtained with these new instruments. There is a strong interest of the astrophysical community in isotopic species for two main reasons: (i) Their detection provides us with key information about interstellar chemical modeling, especially for complex organic molecules, like methyl formate, as their formation mechanisms is not well understood yet. (ii) They are responsible for a large fraction of U-lines and their assignments are necessary to allow the detection of new species. In this context we continue a systematic study of the isotopic species of methyl formate (HCOOCH_3) initiated with H^{13}COOCH_3. Our next investigation of HCOO^{13}CH_3 allowed us the detection of 500 lines in Orion. The treatment of the data concerning methyl formate is not obvious due to the internal rotation of the methyl group. This treatment is different in case of a symmetric (CH_3) or an asymmetric (CHD_2) rotor part. We will report here on recent results obtained for DCOOCH_3, HCOOCHD_2, HC^{18}OOCH_3, and HCO^{18}OCH_3. [2] Willaert, Møllendal, Alekseev, et al. J. Mol. Struct. 795 (2006) [3] Carvajal, Margules, Tercero, et al. Astron. Astrophys. (2009) in press

  1. A Complete Census of Dense Cores in Chamaeleon I: Results from an ALMA Cycle 1 Survey

    NASA Astrophysics Data System (ADS)

    Dunham, Michael; Schnee, Scott; Pineda, Jaime E.; Offner, Stella; Price, Daniel; Arce, Hector G.; Di Francesco, James; Johnstone, Doug I.; Bourke, Tyler L.; Tobin, John J.; Chen, Xuepeng

    2015-01-01

    Stars form from the gravitational collapse of dense molecular cloud cores, yet many details relating to the onset of collapse and fragmentation into multiple systems remain unknown. I will present the results of an ALMA cycle 1 survey of all known dense cores (starless and protostellar) in the Chamaeleon I molecular cloud complex (d~170pc). The goals of this survey are to provide a complete census of protostars, including those too young, too low in luminosity, and/or too deeply embedded to detect in previous infrared and (sub)millimeter surveys, and to characterize when and how dense cores fragment into multiple systems. With these results we will report new detections of protostellar multiplicity and provide updated constraints on the fraction of starless cores that are truly starless, the lifetime of the first hydrostatic core phase, and the relative durations of the starless and protostellar core populations. We will also report a lack of detections among the starless cores and discuss implications of these results.

  2. Molecular Line Emission from Massive Protostellar Disks: Predictions for ALMA and the EVLA

    SciTech Connect

    Krumholz, M R; Klein, R I; McKee, C F

    2007-05-07

    We compute the molecular line emission of massive protostellar disks by solving the equation of radiative transfer through the cores and disks produced by the recent radiation-hydrodynamic simulations of Krumholz, Klein, & McKee. We find that in several representative lines the disks show brightness temperatures of hundreds of Kelvin over velocity channels {approx} 10 km s{sup -1} wide, extending over regions hundreds of AU in size. We process the computed intensities to model the performance of next-generation radio and submillimeter telescopes. Our calculations show that observations using facilities such as the EVLA and ALMA should be able to detect massive protostellar disks and measure their rotation curves, at least in the nearest massive star-forming regions. They should also detect significant sub-structure and non-axisymmetry in the disks, and in some cases may be able to detect star-disk velocity offsets of a few km s{sup -1}, both of which are the result of strong gravitational instability in massive disks. We use our simulations to explore the strengths and weaknesses of different observational techniques, and we also discuss how observations of massive protostellar disks may be used to distinguish between alternative models of massive star formation.

  3. IRAS 16547–4247: A NEW CANDIDATE OF A PROTOCLUSTER UNVEILED WITH ALMA

    SciTech Connect

    Higuchi, Aya E.; Saigo, Kazuya; Chibueze, James O.; Sanhueza, Patricio; Takakuwa, Shigehisa; Garay, Guido

    2015-01-10

    We present the results of continuum and {sup 12}CO(3-2) and CH{sub 3}OH(7-6) line observations of IRAS 16547–4247 made with the Atacama Large Millimeter/submillimeter Array (ALMA) at an angular resolution of ∼0.''5. The {sup 12}CO(3-2) emission shows two high-velocity outflows whose driving sources are located within the dust continuum peak. The alignment of these outflows does not coincide with that of the wide-angle, large-scale, bipolar outflow detected with the Atacama Pathfinder Experiment in previous studies. The CH{sub 3}OH(7-6) line emission traces an hourglass structure associated with the cavity walls created by the outflow lobes. Taking into account our results together with the position of the H{sub 2}O and class I CH{sub 3}OH maser clusters, we discuss two possible scenarios that can explain the hourglass structure observed in IRAS 16547–4247: (1) precession of a biconical jet, (2) multiple, or at least two, driving sources powering intersecting outflows. Combining the available evidence, namely, the presence of two cross-aligned bipolar outflows and two different H{sub 2}O maser groups, we suggest that IRAS 16547–4247 represents an early formation phase of a protocluster.

  4. Implementing Kanban for agile process management within the ALMA Software Operations Group

    NASA Astrophysics Data System (ADS)

    Reveco, Johnny; Mora, Matias; Shen, Tzu-Chiang; Soto, Ruben; Sepulveda, Jorge; Ibsen, Jorge

    2014-07-01

    After the inauguration of the Atacama Large Millimeter/submillimeter Array (ALMA), the Software Operations Group in Chile has refocused its objectives to: (1) providing software support to tasks related to System Integration, Scientific Commissioning and Verification, as well as Early Science observations; (2) testing the remaining software features, still under development by the Integrated Computing Team across the world; and (3) designing and developing processes to optimize and increase the level of automation of operational tasks. Due to their different stakeholders, each of these tasks presents a wide diversity of importances, lifespans and complexities. Aiming to provide the proper priority and traceability for every task without stressing our engineers, we introduced the Kanban methodology in our processes in order to balance the demand on the team against the throughput of the delivered work. The aim of this paper is to share experiences gained during the implementation of Kanban in our processes, describing the difficulties we have found, solutions and adaptations that led us to our current but still evolving implementation, which has greatly improved our throughput, prioritization and problem traceability.

  5. Spectroscopic Confirmation of Ethyl Cyanide in Titan’s Atmosphere using ALMA

    NASA Astrophysics Data System (ADS)

    Palmer, Maureen Y.; Cordiner, Martin A.; Nixon, Conor A.; Kisiel, Zbigniew; Charnley, Steven B.; Teanby, Nick; Kuan, Yi-Jehng; Mumma, Michael J.

    2014-11-01

    In the last few decades, many molecular species have been detected in the atmosphere of Titan. The first detection of a new molecule on Titan using high-resolution microwave spectroscopy was by Bézard et al. (1993), who observed multiple emission lines from methyl cyanide (CH3CN) near 221 GHz. The presence of ethyl cyanide (CH3CH2CN) has long been predicted by photochemical models, and the protonated form (CH3CH2CNH+) was previously inferred from Cassini INMS measurements (Vuitton et al. 2006). Here, we present the first spectroscopic detection of ethyl cyanide in Titan's atmosphere, obtained using high spectral/spatial-resolution observations carried out with the Atacama Large Millimeter/sub-millimeter Array (ALMA). We have detected over 30 rotational emission lines from CH3CH2CN in the frequency range 220-350 GHz, and will present a preliminary model for the column density, as well as maps of the CH3CH2CN distribution in Titan's daylight hemisphere.References: Vuitton, Yelle, & Anicich 2006, ApJ, 647, L175.; Bézard, B., Marten, A., & Paubert, G. (1993). Detection of Acetonitrile on Titan. In AAS/Division for Planetary Sciences Meeting Abstracts #25.09, vol. 25 of Bulletin of the American Astronomical Society, (p. 1100).

  6. ORIGIN AND KINEMATICS OF THE ERUPTIVE FLOW FROM XZ TAU REVEALED BY ALMA

    SciTech Connect

    Zapata, Luis A.; Galván-Madrid, Roberto; Carrasco-González, Carlos; Palau, Aina; Rodríguez, Luis F.; Kurtz, Stan E.; Tafoya, Daniel; Loinard, Laurent; Curiel, Salvador

    2015-09-20

    We present high angular resolution (∼0.″94) {sup 12}CO(1-0) Atacama Large Millimeter/submillimeter Array (ALMA) observations obtained during the 2014 long baseline campaign from the eruptive bipolar flow from the multiple XZ Tau stellar system discovered by the Hubble Space Telescope (HST). These observations reveal, for the first time, the kinematics of the molecular flow. The kinematics of the different ejections close to XZ Tau reveal a rotating and expanding structure with a southeast–northwest velocity gradient. The youngest eruptive bubbles unveiled in the optical HST images are inside of this molecular expanding structure. Additionally, we report a very compact and collimated bipolar outflow emanating from XZ Tau A, which indicates that the eruptive outflow is indeed originating from this object. The mass (3 × 10{sup −7} M{sub ⊙}) and energetics (E{sub kin} = 3 × 10{sup 37} erg) for the collimated outflow are comparable to those found in molecular outflows associated with young brown dwarfs.

  7. Alma observations of nearby luminous infrared galaxies with various agn energetic contributions using dense gas tracers

    SciTech Connect

    Imanishi, Masatoshi; Nakanishi, Kouichiro

    2014-07-01

    We present the results of our ALMA Cycle 0 observations, using HCN/HCO{sup +}/HNC J = 4-3 lines, of six nearby luminous infrared galaxies with various energetic contributions from active galactic nuclei (AGNs) estimated from previous infrared spectroscopy. These lines are very effective for probing the physical properties of high-density molecular gas around the hidden energy sources in the nuclear regions of these galaxies. We find that HCN to HCO{sup +} J = 4-3 flux ratios tend to be higher in AGN-important galaxies than in starburst-dominated regions, as was seen at the J = 1-0 transition, while there is no clear difference in the HCN-to-HNC J = 4-3 flux ratios among observed sources. A galaxy with a starburst-type infrared spectral shape and very large molecular line widths shows a high HCN-to-HCO{sup +} J = 4-3 flux ratio, which could be due to turbulence-induced heating. We propose that enhanced HCN J = 4-3 emission relative to HCO{sup +} J = 4-3 could be used to detect more energetic activity than normal starbursts, including deeply buried AGNs, in dusty galaxy populations.

  8. Stacking of Interferometric Data: New Tools for Stacking of ALMA Data

    NASA Astrophysics Data System (ADS)

    Knudsen, K. K.; Lindroos, L.; Vlemmings, W.; Conway, J.; Martí-Vidal, I.

    2015-12-01

    Radio and mm observations play an important role in determining the star formation properties of high-redshift galaxies. With the unprecedented sensitivity, ALMA now enable studies of faint , distant star-forming galaxies. However, most galaxies with low star formation rates at high redshift are too faint to be detected individually at these wavelengths. A way to study such galaxies is to use stacking. By averaging the emission of a large number of galaxies detected in optical or near-infrared surveys, we can achieve statistical detection. We investigate methods for stacking data from interferometric surveys. Interferometry poses unique challenges in stacking due to the nature of this data. We have compared stacking of uv-data with stacking of imaged data, the latter being the commonly used approach. Using simulated data, we find that uv-stacking may provide up to 50% less noise and that image based stacking systematically loses around 10% of the flux. More importantly, we find that the uv-stacking yield more robust results, especially in the case of (marginally) resolved sources and mosaicked data.

  9. An ALMA continuum survey of circumstellar disks in the upper Scorpius OB association

    SciTech Connect

    Carpenter, John M.; Ricci, Luca; Isella, Andrea

    2014-05-20

    We present ALMA 880 μm continuum observations of 20 K- and M-type stars in the Upper Scorpius OB association (Upper Sco) that are surrounded by protoplanetary disks. These data are used to measure the dust content in disks around low-mass stars (0.1-1.6 M {sub ☉}) at a stellar age of 5-11 Myr. Thirteen sources were detected in the 880 μm dust continuum at ≥3σ with inferred dust masses between 0.3 and 52 M {sub ⊕}. The dust masses tend to be higher around the more massive stars, but the significance is marginal in that the probability of no correlation is p ≈ 0.03. The evolution in the dust content in disks was assessed by comparing the Upper Sco observations with published continuum measurements of disks around ∼1-2 Myr stars in the Class II stage in the Taurus molecular cloud. While the dust masses in the Upper Sco disks are on average lower than in Taurus, any difference in the dust mass distributions is significant at less than 3σ. For stellar masses between 0.49 M {sub ☉} and 1.6 M {sub ☉}, the mean dust mass in disks is lower in Upper Sco relative to Taurus by Δlog M {sub dust} = 0.44 ± 0.26.

  10. A Community-Engaged Research Approach to Improve Mental Health Among Latina Immigrants: ALMA Photovoice.

    PubMed

    Perez, Georgina; Della Valle, Pamela; Paraghamian, Sarah; Page, Rachel; Ochoa, Janet; Palomo, Fabiana; Suarez, Emilia; Thrasher, Angela; Tran, Anh N; Corbie-Smith, Giselle

    2016-05-01

    Recent Latina immigrants are at increased risk of poor mental health due to stressors associated with adapting to life in the United States. Existing social and health care policies often do not adequately address the mental health concerns of new Latino populations. Amigas Latinas Motivando el Alma, a community-partnered research project, seeks to improve immigrant Latinas' mental health outcomes. Using Photovoice methodology, promotoras (lay health advisors) reflected on community factors affecting mental health through photography and guided discussion. Discussions were audio-recorded, transcribed, and coded using content analysis to identify salient themes. Promotoras reviewed codes to develop themes that they presented in community forums to reach local policy makers and to increase community awareness. These forums included an exhibit of the promotoras' photographs and discussion of action steps to address community concerns. Themes included transitioning to life in the United States, parenting, education, and combating racism. Nearly 150 stakeholders attended the community forums and proposed responses to promotoras' photographic themes. Our findings suggest that Photovoice provides an opportunity for Latinas and the larger community to identify issues that they find most important and to explore avenues for action and change by creating sustainable partnerships between the community and forum attendees.

  11. HIGH-DENSITY MOLECULAR GAS PROPERTIES OF THE STARBURST GALAXY NGC 1614 REVEALED WITH ALMA

    SciTech Connect

    Imanishi, Masatoshi; Nakanishi, Kouichiro

    2013-09-15

    We present the results of HCN/HCO{sup +}/HNC J = 4-3 transition line observations of the nearby starburst galaxy NGC 1614, obtained with ALMA Cycle 0. We find that high density molecular gas traced with these lines shows a velocity structure such that the northern (southern) side of the nucleus is redshifted (blueshifted) with respect to the nuclear velocity of this galaxy. The redshifted and blueshifted emission peaks are offset by {approx}0.''6 at the northern and southern sides of the nucleus, respectively. At these offset positions, observations at infrared >3 {mu}m indicate the presence of active dusty starbursts, supporting the picture that high-density molecular gas is the site of active starbursts. The enclosed dynamical mass within the central {approx}2'' in radius, derived from the dynamics of the high-density molecular gas, is {approx}10{sup 9} M{sub Sun }, which is similar to previous estimates. Finally, the HCN emission is weaker than HCO{sup +} but stronger than HNC for J = 4-3 for all starburst regions of NGC 1614, as seen for J = 1-0 transition lines in starburst-dominated galaxies.

  12. Protoplanetary Disks in the Orion OMC1 Region Imaged with ALMA

    NASA Astrophysics Data System (ADS)

    Eisner, J. A.; Bally, J. M.; Ginsburg, A.; Sheehan, P. D.

    2016-07-01

    We present ALMA observations of the Orion Nebula that cover the OMC1 outflow region. Our focus in this paper is on compact emission from protoplanetary disks. We mosaicked a field containing ˜600 near-IR-identified young stars, around which we can search for sub-millimeter emission tracing dusty disks. Approximately 100 sources are known proplyds identified with the Hubble Space Telescope. We detect continuum emission at 1 mm wavelengths toward ˜20% of the proplyd sample, and ˜8% of the larger sample of near-IR objects. The noise in our maps allows 4σ detection of objects brighter than ˜1.5 mJy, corresponding to protoplanetary disk masses larger than 1.5 M J (using standard assumptions about dust opacities and gas-to-dust ratios). None of these disks are detected in contemporaneous CO(2-1) or C18O(2-1) observations, suggesting that the gas-to-dust ratios may be substantially smaller than the canonical value of 100. Furthermore, since dust grains may already be sequestered in large bodies in Orion Nebula cluster (ONC) disks, the inferred masses of disk solids may be underestimated. Our results suggest that the distribution of disk masses in this region is compatible with the detection rate of massive planets around M dwarfs, which are the dominant stellar constituent in the ONC.

  13. THE PECULIAR DISTRIBUTION OF CH3CN IN IRC +10216 SEEN BY ALMA

    PubMed Central

    Agúndez, M.; Cernicharo, J.; Quintana-Lacaci, G.; Prieto, L. Velilla; Castro-Carrizo, A.; Marcelino, N.; Guélin, M.

    2015-01-01

    IRC +10216 is a circumstellar envelope around a carbon-rich evolved star which contains a large variety of molecules. According to interferometric observations, molecules are distributed either concentrated around the central star or as a hollow shell with a radius of ~15″. We present ALMA Cycle 0 band 6 observations of the J = 14 – 13 rotational transition of CH3CN in IRC +10216, obtained with an angular resolution of 0.″76×0.″61. The bulk of the emission is distributed as a hollow shell located at just ~2″ from the star, with a void of emission in the central region up to a radius of ~1″. This spatial distribution is markedly different from those found to date in this source for other molecules. Our analysis indicate that methyl cyanide is not formed neither in the stellar photosphere nor far in the outer envelope, but at radial distances as short as 1-2″, reaching a maximum abundance of ~ 0.02 molecules cm−3 at 2″ from the star. Standard chemical models of IRC +10216 predict that the bulk of CH3CN molecules should be present at a radius of ~ 15″, where other species such as polyyne radicals and cyanopolyynes are observed, with an additional inner component within 1″ from the star. The non-uniform structure of the circumstellar envelope and grain surface processes are discussed as possible causes of the peculiar distribution of methyl cyanide in IRC +10216. PMID:26709313

  14. Tracing the Origins of Nitrogen Bearing Organics Toward Orion KL with Alma

    NASA Astrophysics Data System (ADS)

    Carroll, Brandon; Crockett, Nathan; Bergin, Edwin; Blake, Geoffrey

    2016-06-01

    A comprehensive analysis of a broadband 1.2 THz wide spectral survey of the Orion Kleinmann-Low nebula (Orion KL) from the Herschel Space Telescope has shown that nitrogen bearing complex organics trace systematically hotter gas than O-bearing organics toward this source. The origin of this O/N dichotomy remains a mystery. If complex molecules originate from grain surfaces, N-bearing species may be more difficult to remove from grain surfaces than O-bearing organics. Theoretical studies, however, have shown that hot (T=300 K) gas phase chemistry can produce high abundances of N-bearing organics while suppressing the formation of O-bearing complex molecules. In order to distinguish these distinct formation pathways we have obtained extremely high angular resolution observations of methyl cyanide (CH_3CN) using the Atacama Large Millimeter/Submillimeter Array (ALMA) toward Orion KL. By simultaneously imaging 13CH_3CN and CH_2DCN we map the temperature structure and D/H ratio of CH_3CN. We will present the initial results of these observations and discuss their implications for the formation of N-bearing organics in the interstellar medium.

  15. The CDMS view on molecular data needs of Herschel, SOFIA, and ALMA

    NASA Astrophysics Data System (ADS)

    Müller, Holger S. P.; Endres, C. P.; Stutzki, J.; Schlemmer, S.

    2013-07-01

    The catalog section of the Cologne Database for Molecular Spectroscopy, CDMS, contains mostly rotational transition frequencies, with auxiliary information, of molecules observable in space. The frequency lists are generated mostly from critically evaluated laboratory data employing established Hamiltonian models. The CDMS has been online publicly for more than 12 years, e.g., via the short-cut http://www.cdms.de. Initially constructed as ascii tables, its inclusion into a database environment within the Virtual Atomic and Molecular Data Centre (VAMDC, http://www.vamdc.eu) has begun in June 2008. A test version of the new CDMS is about to be released. The CDMS activities have been part of the extensive laboratory spectroscopic investigations in Cologne. Moreover, these activities have also benefit from collaborations with other laboratory spectroscopy groups as well as with astronomers. We will provide some basic information on the CDMS and its participation in the VAMDC project. In addition, some recent detections of molecules as well as spectroscopic studies will be discussed to evaluate the spectroscopic data needs of Herschel, SOFIA, and ALMA in particular in terms of light hydrides, complex molecules, and metal containing species.

  16. Comparing ALMA, VLT, and HST data for Massive, Young Clusters in Grand-Design Spirals

    NASA Astrophysics Data System (ADS)

    Grosboel, Preben; Dottori, Horacio

    2015-08-01

    A population of young, massive stellar cluster complexes with near-infrared (NIR) colors indicating high extinction (i.e. Av ~ 7mag) was identified on HAWK-I/VLT images of several nearby, grand-design spiral galaxies (Grosboel & Dottori 2012, A&A 542, A39). Models suggest that they are very young cluster complexes still embedded in a dust/gas envelope which will be expelled after the first supernovae explosions (Grosboel & Dottori 2013, A&A 551, L13). Optical studies of nearby disk galaxies using HST data (see e.g. Larsen & Richtler 1999 A&A 345, 49, and Bastian et al. 2012, MNRAS 419, 2606) do not find a similar population of clusters. This may be due to several reasons such as a) lower spatial resolution of the NIR data (Bastian et al. 2014, MNRAS 444, 3829), b) high attenuation by dust limiting detection at optical wavelengths, or c) such populations only exist in grand-design spirals due to the strong perturbations in their arm regions. The current paper presents a detailed comparison of HST and HAWK-I images to better understand the discrepancy between the optical and NIR detection of stellar clusters in nearby galaxies. Further, the ALMA CO-map of NGC 4321 is compared with the VLT NIR images to analyze the possible correlation between giant molecular clouds and formation of massive clusters.

  17. Revised spectroscopic parameters of SH(+) from ALMA and IRAM 30m observations.

    PubMed

    Müller, Holger S P; Goicoechea, Javier R; Cernicharo, José; Agúndez, Marcelino; Pety, Jérôme; Cuadrado, Sara; Gerin, Maryvonne; Dumas, Gaëlle; Chapillon, Edwige

    2014-09-19

    Hydrides represent the first steps of interstellar chemistry. Sulfanylium (SH(+)), in particular, is a key tracer of energetic processes. We used ALMA and the IRAM 30 m telescope to search for the lowest frequency rotational lines of SH(+) toward the Orion Bar, the prototypical photo-dissociation region illuminated by a strong UV radiation field. On the basis of previous Herschel/HIFI observations of SH(+), we expected to detect emission of the two SH(+) hyperfine structure (HFS) components of the NJ = 10-01 fine structure (FS) component near 346 GHz. While we did not observe any lines at the frequencies predicted from laboratory data, we detected two emission lines, each ~15 MHz above the SH(+) predictions and with relative intensities and HFS splitting expected for SH(+). The rest frequencies of the two newly detected lines are more compatible with the remainder of the SH(+) laboratory data than the single line measured in the laboratory near 346 GHz and previously attributed to SH(+). Therefore, we assign these new features to the two SH(+) HFS components of the NJ = 10-01 FS component and re-determine its spectroscopic parameters, which will be useful for future observations of SH(+), in particular if its lowest frequency FS components are studied. Our observations demonstrate the suitability of these lines for SH(+) searches at frequencies easily accessible from the ground. PMID:26525172

  18. SXDF-ALMA 2 arcmin2 deep survey: Resolving and characterizing the infrared extragalactic background light down to 0.5 mJy

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Yuki; Tamura, Yoichi; Kohno, Kotaro; Aretxaga, Itziar; Dunlop, James S.; Hatsukade, Bunyo; Hughes, David; Ikarashi, Soh; Ishii, Shun; Ivison, Rob J.; Izumi, Takuma; Kawabe, Ryohei; Kodama, Tadayuki; Lee, Minju; Makiya, Ryu; Matsuda, Yuichi; Nakanishi, Kouichiro; Ohta, Kouji; Rujopakarn, Wiphu; Tadaki, Ken-ichi; Umehata, Hideki; Wang, Wei-Hao; Wilson, Grant W.; Yabe, Kiyoto; Yun, Min S.

    2016-08-01

    We present a multiwavelength analysis of five submillimeter sources (S1.1mm = 0.54-2.02 mJy) that were detected during our 1.1 mm deep continuum survey in the Subaru/XMM-Newton Deep Survey Field (SXDF)-UDS-CANDELS field (2 arcmin2, 1σ = 0.055 mJy beam-1) using the Atacama Large Millimeter/submillimeter Array (ALMA). The two brightest sources correspond to a known single-dish (AzTEC) selected bright submillimeter galaxy (SMG), whereas the remaining three are faint SMGs newly uncovered by ALMA. If we exclude the two brightest sources, the contribution of the ALMA-detected faint SMGs to the infrared extragalactic background light is estimated to be ˜ 4.1^{+5.4}_{-3.0}Jy deg-2, which corresponds to ˜ 16^{+22}_{-12}% of the infrared extragalactic background light. This suggests that their contribution to the infrared extragalactic background light is as large as that of bright SMGs. We identified multiwavelength counterparts of the five ALMA sources. One of the sources (SXDF-ALMA3) is extremely faint in the optical to near-infrared region despite its infrared luminosity (L_IR˜eq 1× 10^{12} L_{⊙} or SFR ≃ 100 M⊙ yr-1). By fitting the spectral energy distributions at the optical-to-near-infrared wavelengths of the remaining four ALMA sources, we obtained the photometric redshifts (zphoto) and stellar masses (M*): zphoto ≃ 1.3-2.5, M* ≃ (3.5-9.5) × 1010 M⊙. We also derived their star formation rates (SFRs) and specific SFRs as ≃30-200 M⊙ yr-1 and ≃0.8-2 Gyr-1, respectively. These values imply that they are main sequence star-forming galaxies.

  19. SXDF-ALMA 2 arcmin2 deep survey: Resolving and characterizing the infrared extragalactic background light down to 0.5 mJy

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Yuki; Tamura, Yoichi; Kohno, Kotaro; Aretxaga, Itziar; Dunlop, James S.; Hatsukade, Bunyo; Hughes, David; Ikarashi, Soh; Ishii, Shun; Ivison, Rob J.; Izumi, Takuma; Kawabe, Ryohei; Kodama, Tadayuki; Lee, Minju; Makiya, Ryu; Matsuda, Yuichi; Nakanishi, Kouichiro; Ohta, Kouji; Rujopakarn, Wiphu; Tadaki, Ken-ichi; Umehata, Hideki; Wang, Wei-Hao; Wilson, Grant W.; Yabe, Kiyoto; Yun, Min S.

    2016-10-01

    We present a multiwavelength analysis of five submillimeter sources (S1.1mm = 0.54-2.02 mJy) that were detected during our 1.1 mm deep continuum survey in the Subaru/XMM-Newton Deep Survey Field (SXDF)-UDS-CANDELS field (2 arcmin2, 1σ = 0.055 mJy beam-1) using the Atacama Large Millimeter/submillimeter Array (ALMA). The two brightest sources correspond to a known single-dish (AzTEC) selected bright submillimeter galaxy (SMG), whereas the remaining three are faint SMGs newly uncovered by ALMA. If we exclude the two brightest sources, the contribution of the ALMA-detected faint SMGs to the infrared extragalactic background light is estimated to be ˜ 4.1^{+5.4}_{-3.0}Jy deg-2, which corresponds to ˜ 16^{+22}_{-12}% of the infrared extragalactic background light. This suggests that their contribution to the infrared extragalactic background light is as large as that of bright SMGs. We identified multiwavelength counterparts of the five ALMA sources. One of the sources (SXDF-ALMA3) is extremely faint in the optical to near-infrared region despite its infrared luminosity (L_IR˜eq 1× 10^{12} L_{⊙} or SFR ≃ 100 M⊙ yr-1). By fitting the spectral energy distributions at the optical-to-near-infrared wavelengths of the remaining four ALMA sources, we obtained the photometric redshifts (zphoto) and stellar masses (M*): zphoto ≃ 1.3-2.5, M* ≃ (3.5-9.5) × 1010 M⊙. We also derived their star formation rates (SFRs) and specific SFRs as ≃30-200 M⊙ yr-1 and ≃0.8-2 Gyr-1, respectively. These values imply that they are main sequence star-forming galaxies.

  20. Toward Precision Black Hole Masses with ALMA: NGC 1332 as a Case Study in Molecular Disk Dynamics

    NASA Astrophysics Data System (ADS)

    Barth, Aaron J.; Darling, Jeremy; Baker, Andrew J.; Boizelle, Benjamin D.; Buote, David A.; Ho, Luis C.; Walsh, Jonelle L.

    2016-05-01

    We present first results from a program of Atacama Large Millimeter/submillimeter Array (ALMA) CO(2-1) observations of circumnuclear gas disks in early-type galaxies. The program was designed with the goal of detecting gas within the gravitational sphere of influence of the central black holes (BHs). In NGC 1332, the 0.″3-resolution ALMA data reveal CO emission from the highly inclined (i≈ 83^\\circ ) circumnuclear disk, spatially coincident with the dust disk seen in Hubble Space Telescope images. The disk exhibits a central upturn in maximum line-of-sight velocity, reaching ±500 km s-1 relative to the systemic velocity, consistent with the expected signature of rapid rotation around a supermassive BH. Rotational broadening and beam smearing produce complex and asymmetric line profiles near the disk center. We constructed dynamical models for the rotating disk and fitted the modeled CO line profiles directly to the ALMA data cube. Degeneracy between rotation and turbulent velocity dispersion in the inner disk precludes the derivation of strong constraints on the BH mass, but model fits allowing for a plausible range in the magnitude of the turbulent dispersion imply a central mass in the range of ˜(4-8) × 108 {M}⊙ . We argue that gas-kinematic observations resolving the BH’s projected radius of influence along the disk’s minor axis will have the capability to yield BH mass measurements that are largely insensitive to systematic uncertainties in turbulence or in the stellar mass profile. For highly inclined disks, this is a much more stringent requirement than the usual sphere-of-influence criterion.

  1. Star formation and chemical complexity in the Orion nebula: A new view with the IRAM and ALMA interferometers

    NASA Astrophysics Data System (ADS)

    Baudry, Alain; Brouillet, Nathalie; Despois, Didier

    2016-11-01

    The Orion nebula is one of the most observed celestial regions in the Milky Way. It is an active massive star-forming region, especially well studied in the millimeter and submillimeter domains that allow us to unveil the cool and obscured regions in which stars are being formed. After a brief introduction to the main properties of a radio telescope, we recall that the most sensitive radio interferometers, the IRAM mm array and, especially, the recently built ALMA millimeter/submillimeter array, offer an outstanding spatial resolution reaching the sub-arcsecond scale, or even about 10 milli-arcseconds for ALMA (about four times the Earth's orbit radius at the Orion distance). These interferometers can reveal the fine spatial details of the Orion clouds of gas and dust within which new stars and associated planetary systems are being formed. The high spectral resolution and sensitivity of both interferometers and the broad instantaneous bandwidth offered by ALMA allowed us to map the emission from a number of complex organic molecules, to estimate the molecular abundances, and to address some important aspects of the molecular complexity in Orion. Our observations do not lead to a unique molecular formation and excitation scheme, but the chemistry at work in the proto-stellar 'fragments' at the center of the Orion nebula can be compared with the chemistry prevailing in comets of the Solar system. We have underlined the possible links between the prebiotic molecules observed in space and the chemistry leading to the early terrestrial life. xml:lang="fr"

  2. DIRECT IMAGING OF THE WATER SNOW LINE AT THE TIME OF PLANET FORMATION USING TWO ALMA CONTINUUM BANDS

    SciTech Connect

    Banzatti, A.; Pontoppidan, K. M.; Pinilla, P.; Ricci, L.; Birnstiel, T.; Ciesla, F.

    2015-12-10

    Molecular snow lines in protoplanetary disks have been studied theoretically for decades because of their importance in shaping planetary architectures and compositions. The water snow line lies in the planet formation region at ≲10 AU, and so far its location has been estimated only indirectly from spatially unresolved spectroscopy. This work presents a proof-of-concept method to directly image the water snow line in protoplanetary disks through its physical and chemical imprint on the local dust properties. We adopt a physical disk model that includes dust coagulation, fragmentation, drift, and a change in fragmentation velocities of a factor of 10 between dry silicates and icy grains as found by laboratory work. We find that the presence of a water snow line leads to a sharp discontinuity in the radial profile of the dust emission spectral index α{sub mm} due to replenishment of small grains through fragmentation. We use the ALMA simulator to demonstrate that this effect can be observed in protoplanetary disks using spatially resolved ALMA images in two continuum bands. We explore the model dependence on the disk viscosity and find that the spectral index reveals the water snow line for a wide range of conditions, with opposite trends when the emission is optically thin rather than thick. If the disk viscosity is low (α{sub visc} < 10{sup −3}), the snow line produces a ringlike structure with a minimum at α{sub mm} ∼ 2 in the optically thick regime, possibly similar to what has been measured with ALMA in the innermost region of the HL Tau disk.

  3. THE ANATOMY OF AN EXTREME STARBURST WITHIN 1.3 Gyr OF THE BIG BANG REVEALED BY ALMA

    SciTech Connect

    Carilli, C. L.; Riechers, D.; Walter, F.; Maiolino, R.; Lentati, L.; Wagg, J.; McMahon, R.; Wolfe, A.

    2013-02-15

    We present further analysis of the [C II] 158 {mu}m fine structure line and thermal dust continuum emission from the archetype extreme starburst/active galactic nucleus (AGN) group of galaxies in the early universe, BRI 1202-0725 at z = 4.7, using the Atacama Large Millimeter Array. The group has long been noted for having a closely separated (26 kpc in projection) FIR-hyperluminous quasar host galaxy and an optically obscured submillimeter galaxy (SMG). A short ALMA test observation reveals a rich laboratory for the study of the myriad processes involved in clustered massive galaxy formation in the early universe. Strong [C II] emission from the SMG and the quasar have been reported earlier by Wagg et al. based on these observations. In this paper, we examine in more detail the imaging results from the ALMA observations, including velocity channel images, position-velocity plots, and line moment images. We present detections of [C II] emission from two Ly{alpha}-selected galaxies in the group, demonstrating the relative ease with which ALMA can detect the [C II] emission from lower star formation rate galaxies at high redshift. Imaging of the [C II] emission shows a clear velocity gradient across the SMG, possibly indicating rotation or a more complex dynamical system on a scale {approx}10 kpc. There is evidence in the quasar spectrum and images for a possible outflow toward the southwest, as well as more extended emission (a {sup b}ridge{sup )}, between the quasar and the SMG, although the latter could simply be emission from Ly{alpha}-1 blending with that of the quasar at the limited spatial resolution of the current observations. These results provide an unprecedented view of a major merger of gas-rich galaxies driving extreme starbursts and AGN accretion during the formation of massive galaxies and supermassive black holes within 1.3 Gyr of the big bang.

  4. 30 Doradus - Relating Young Stars Imaged by Spitzer and Hubble to the CO Molecular Gas Observed with ALMA

    NASA Astrophysics Data System (ADS)

    Nayak, Omnarayani; Meixner, Margaret; Indebetouw, Remy; Sabbi, Elena; De Marchi, Guido; Panagia, Nino

    2016-01-01

    The majority of star have masses less than 8 solar mass and form in clumps that are less than 1 pc in size. The sub-parsec scales in which star formation takes place makes it difficult to resolve the effects star formation and the surrounding dense gas have on each other. The Magellanic Clouds are more active in forming high mass stars as compared to the Milky Way. The SAGE and Heritage surveys combined with the Hubble Tarantula Treasury Project provide us the opportunity to study high-mass (>15 solar masses) and low-mass (<1 solar mass) star formation. ALMA observations cover a 60 pc x 30 pc region of CO gas slightly north of the R136 cluster in 30 Doradus. We find 16 young stellar objects and about a 100 pre-main-sequence stars within the ALMA footprint. We define young stellar objects to be very early stage stars that are about 10,000 years old and whose SEDs peak in the infrared, and we use pre-main-sequence-stars to refer to slightly older stars that can be seen in the optical. I will use dendrograms to analyze both the high- and low-mass star properties with respect to the CO gas structure observed with ALMA. Preliminary results show that not all massive young stellar objects are associated with CO gas, higher mass clumps tend to form higher mass stars and are more likely to have multiple young stars, and lower mass clumps tend to not be gravitationally bound however the larger clouds are bound. Looking at the interplay between dense molecular gas and the newly forming stars in a stellar nursery will shed light on how these stars formed: monolithic collapse or competitive accretion.

  5. Direct Imaging of the Water Snow Line at the Time of Planet Formation using Two ALMA Continuum Bands

    NASA Astrophysics Data System (ADS)

    Banzatti, A.; Pinilla, P.; Ricci, L.; Pontoppidan, K. M.; Birnstiel, T.; Ciesla, F.

    2015-12-01

    Molecular snow lines in protoplanetary disks have been studied theoretically for decades because of their importance in shaping planetary architectures and compositions. The water snow line lies in the planet formation region at ≲10 AU, and so far its location has been estimated only indirectly from spatially unresolved spectroscopy. This work presents a proof-of-concept method to directly image the water snow line in protoplanetary disks through its physical and chemical imprint on the local dust properties. We adopt a physical disk model that includes dust coagulation, fragmentation, drift, and a change in fragmentation velocities of a factor of 10 between dry silicates and icy grains as found by laboratory work. We find that the presence of a water snow line leads to a sharp discontinuity in the radial profile of the dust emission spectral index αmm due to replenishment of small grains through fragmentation. We use the ALMA simulator to demonstrate that this effect can be observed in protoplanetary disks using spatially resolved ALMA images in two continuum bands. We explore the model dependence on the disk viscosity and find that the spectral index reveals the water snow line for a wide range of conditions, with opposite trends when the emission is optically thin rather than thick. If the disk viscosity is low (αvisc < 10‑3), the snow line produces a ringlike structure with a minimum at αmm ∼ 2 in the optically thick regime, possibly similar to what has been measured with ALMA in the innermost region of the HL Tau disk.

  6. The Fundamental Structure of UV-Irradiated Cloud Edges: Combined ALMA and IRAM-30m Observations of the Orion Bar

    NASA Astrophysics Data System (ADS)

    Goicoechea, J.; Cuadrado, S.; Pety, J.; Ag'undez, M.; Cernicharo, J.; Chapillon, E.; Dumas, G.; Fuente, A.; Gerin, M.; Joblin, C.; Marcelino, N.; Müller, H. S. P.; Pilleri, P.

    2015-12-01

    The Orion Bar is the prototypical photodissociation region (PDR) exposed to a far-UV radiation field (FUV) of a few 104 times the mean interstellar field. Because of its proximity and nearly edge-on orientation, it provides a unique laboratory to study the physical and chemical gradients of a strongly FUV-illuminated molecular cloud. Using ALMA at ˜350 GHz, we have observed a field-of-view of ˜40”×40” toward the Orion Bar PDR consisting of a mosaic of 27 Nyquist-sampled pointings. These observations provide an unprecedented high angular resolution view (˜1” or ˜414 AU at the distance to Orion) of the most exposed molecular cloud edge. In addition, ACA and IRAM-30m maps were used to produce the short-spacing visibilities filtered out by the ALMA array. These interferometric observations complement a complete line survey we have carried out using the IRAM-30m telescope between ˜80 GHz and ˜360 GHz. Despite being a harsh environment, over 60 species with up to 6 atoms have been identified, including main isotopologues (D, 13C, 18O, 17O, 34S, 33S, and 15N). The first molecular line images of the Orion Bar obtained with ALMA at ˜1” resolution reveal the fundamental structure in density and temperature of the molecular gas as well as its complex kinematics at an unprecedented spatial resolution. This early data set also allowed us to compute corrected line frequencies for SH+, an interesting hydride tracing reactions of S+ with vibrationally excited H2 in the PDR edge.

  7. Direct Imaging of the Water Snow Line at the Time of Planet Formation using Two ALMA Continuum Bands

    NASA Astrophysics Data System (ADS)

    Banzatti, A.; Pinilla, P.; Ricci, L.; Pontoppidan, K. M.; Birnstiel, T.; Ciesla, F.

    2015-12-01

    Molecular snow lines in protoplanetary disks have been studied theoretically for decades because of their importance in shaping planetary architectures and compositions. The water snow line lies in the planet formation region at ≲10 AU, and so far its location has been estimated only indirectly from spatially unresolved spectroscopy. This work presents a proof-of-concept method to directly image the water snow line in protoplanetary disks through its physical and chemical imprint on the local dust properties. We adopt a physical disk model that includes dust coagulation, fragmentation, drift, and a change in fragmentation velocities of a factor of 10 between dry silicates and icy grains as found by laboratory work. We find that the presence of a water snow line leads to a sharp discontinuity in the radial profile of the dust emission spectral index αmm due to replenishment of small grains through fragmentation. We use the ALMA simulator to demonstrate that this effect can be observed in protoplanetary disks using spatially resolved ALMA images in two continuum bands. We explore the model dependence on the disk viscosity and find that the spectral index reveals the water snow line for a wide range of conditions, with opposite trends when the emission is optically thin rather than thick. If the disk viscosity is low (αvisc < 10-3), the snow line produces a ringlike structure with a minimum at αmm ˜ 2 in the optically thick regime, possibly similar to what has been measured with ALMA in the innermost region of the HL Tau disk.

  8. ALMA and HST Observations of the Molecular Environment, Star formation Activity and Cluster Dissolution In NGC 1097

    NASA Astrophysics Data System (ADS)

    Sheth, Kartik; Regan, Michael W.; Ngcebetsha, Buntu; Kohno, Kotaro; Teuben, Peter J.; Vogel, Stuart N.; Villard, Eric; Wiklind, Tommy; Lundgren, Andreas

    2015-01-01

    Barred spiral galaxies, such as NGC 1097, are an ideal laboratory for studying the interplay between the molecular gas environment and recent star formation activity because there are several dynamically distinct environs (the circumnuclear ring, the bar dust lanes and spurs, the bar end, the inner ring and spiral arms) where the SF activity varies by over three orders of magnitude. We present new ALMA Cycle 1 data showing the CO(1-0), HCN, HCO+, CS, 13CO, C18O emission across the entire disk of NGC 1097 at a resolution of 75 pc (1'). We map the distribution and kinematics of the molecular ISM and quantify the free fall time and shear to constrain what initiates (or inhibits) the star formation activity. By combining the 12m primary array, ACA-7m and total power data we show the most complete maps of NGC 1097. We use the high resolution data to measure the gas inflow rate and accretion onto the circumnuclear ring and constrain the feeding of the central AGN. The 13CO / 12CO ratio across the different environments is used to measure and quantify the diffuse versus dense phases of the molecular ISM across the disk of the galaxy. Finally we compare the ALMA data to new HST UV & optical data to measure the ages and locations of young star clusters. By comparing the cluster age and morphology to the ALMA data we constrain the cluster dissolution time scales as a function of the molecular ISM. Finally we show new JVLA C, X and Ka band continuum data to distinguish between old and young star formation activity.

  9. The Detection of a Hot Molecular Core in the Large Magellanic Cloud with ALMA

    NASA Astrophysics Data System (ADS)

    Shimonishi, Takashi; Onaka, Takashi; Kawamura, Akiko; Aikawa, Yuri

    2016-08-01

    We report the first detection of a hot molecular core outside our Galaxy based on radio observations with ALMA toward a high-mass young stellar object (YSO) in a nearby low metallicity galaxy, the Large Magellanic Cloud (LMC). Molecular emission lines of CO, C17O, HCO+, H13CO+, H2CO, NO, SiO, H2CS, 33SO, 32SO2, 34SO2, and 33SO2 are detected from a compact region (˜0.1 pc) associated with a high-mass YSO, ST11. The temperature of molecular gas is estimated to be higher than 100 K based on rotation diagram analysis of SO2 and 34SO2 lines. The compact source size, warm gas temperature, high density, and rich molecular lines around a high-mass protostar suggest that ST11 is associated with a hot molecular core. We find that the molecular abundances of the LMC hot core are significantly different from those of Galactic hot cores. The abundances of CH3OH, H2CO, and HNCO are remarkably lower compared to Galactic hot cores by at least 1-3 orders of magnitude. We suggest that these abundances are characterized by the deficiency of molecules whose formation requires the hydrogenation of CO on grain surfaces. In contrast, NO shows a high abundance in ST11 despite the notably low abundance of nitrogen in the LMC. A multitude of SO2 and its isotopologue line detections in ST11 imply that SO2 can be a key molecular tracer of hot core chemistry in metal-poor environments. Furthermore, we find molecular outflows around the hot core, which is the second detection of an extragalactic protostellar outflow. In this paper, we discuss the physical and chemical characteristics of a hot molecular core in the low metallicity environment.

  10. Debris Disks in the Scorpius–Centaurus OB Association Resolved by ALMA

    NASA Astrophysics Data System (ADS)

    Lieman-Sifry, Jesse; Hughes, A. Meredith; Carpenter, John M.; Gorti, Uma; Hales, Antonio; Flaherty, Kevin M.

    2016-09-01

    We present a CO(2-1) and 1240 μm continuum survey of 23 debris disks with spectral types B9-G1, observed at an angular resolution of 0.″5–1″ with the Atacama Large Millimeter/Submillimeter Array (ALMA). The sample was selected for large infrared excess and age ˜10 Myr, to characterize the prevalence of molecular gas emission in young debris disks. We identify three CO-rich debris disks, plus two additional tentative (3σ) CO detections. Twenty disks were detected in the continuum at the >3σ level. For the 12 disks in the sample that are spatially resolved by our observations, we perform an independent analysis of the interferometric continuum visibilities to constrain the basic dust disk geometry, as well as a simultaneous analysis of the visibilities and broadband spectral energy distribution to constrain the characteristic grain size and disk mass. The gas-rich debris disks exhibit preferentially larger outer radii in their dust disks, and a higher prevalence of characteristic grain sizes smaller than the blowout size. The gas-rich disks do not exhibit preferentially larger dust masses, contrary to expectations for a scenario in which a higher cometary destruction rate would be expected to result in a larger mass of both CO and dust. The three debris disks in our sample with strong CO detections are all around A stars: the conditions in disks around intermediate-mass stars appear to be the most conducive to the survival or formation of CO.

  11. Brown dwarf disks with ALMA: Evidence for truncated dust disks in Ophiuchus

    NASA Astrophysics Data System (ADS)

    Testi, L.; Natta, A.; Scholz, A.; Tazzari, M.; Ricci, L.; de Gregorio Monsalvo, I.

    2016-10-01

    Context. The study of the properties of disks around young brown dwarfs can provide important clues on the formation of these very low-mass objects and on the possibility of forming planetary systems around them. The presence of warm dusty disks around brown dwarfs is well known, based on near- and mid-infrared studies. Aims: High angular resolution observations of the cold outer disk are limited; we used ALMA to attempt a first survey of young brown dwarfs in the ρ Oph star-forming region. Methods: All 17 young brown dwarfs in our sample were observed at 890 μm in the continuum at 0.̋5 angular resolution. The sensitivity of our observations was chosen to detect ~0.5 M⊕ of dust. Results: We detect continuum emission in 11 disks (~65% of the total), and the estimated mass of dust in the detected disks ranges from ~0.5 to ~6 M⊕. These disk masses imply that planet formation around brown dwarfs may be relatively rare and that the supra-Jupiter mass companions found around some brown dwarfs are probably the result of a binary system formation. We find evidence that the two brightest disks in ρ Oph have sharp outer edges at R ≲ 25 AU, in contrast to disks around Taurus brown dwarfs. This difference may suggest that the different environment in ρ Oph may lead to significant differences in disk properties. A comparison of the Mdisk/M∗ ratio for brown dwarf and solar-mass systems also shows a possible deficit of mass in brown dwarfs, which could support the evidence for dynamical truncation of disks in the substellar regime. These findings are still tentative and need to be put on firmer grounds by studying the gaseous disks around brown dwarfs and by performing a more systematic and unbiased survey of the disk population around the more massive stars.

  12. Molecular gas in the x-ray bright group NGC 5044 as revealed by ALMA

    SciTech Connect

    David, Laurence P.; Forman, William; Vrtilek, Jan; Jones, Christine; O'Sullivan, Ewan; Lim, Jeremy; Combes, Francoise; Salome, Philippe; Edge, Alastair; Hamer, Stephen; Sun, Ming; Gastaldello, Fabio; Bardelli, Sandro; Temi, Pasquale; Ohyama, Youichi; Mathews, William; Giacintucci, Simona; Trung, Dinh-V

    2014-09-10

    An ALMA observation of the early-type galaxy NGC 5044, which resides at the center of an X-ray bright group with a moderate cooling flow, detected 24 molecular structures within the central 2.5 kpc. The masses of the molecular structures vary from 3 × 10{sup 5} M {sub ☉} to 10{sup 7} M {sub ☉} and the CO(2-1) linewidths vary from 15 to 65 km s{sup –1}. Given the large CO(2-1) linewidths, the observed structures are likely giant molecular associations (GMAs) and not individual giant molecular clouds (GMCs). Only a few of the GMAs are spatially resolved and the average density of these GMAs yields a GMC volume filling factor of about 15%. The masses of the resolved GMAs are insufficient for them to be gravitationally bound, however, the most massive GMA does contain a less massive component with a linewidth of 5.5 km s{sup –1} (typical of an individual virialized GMC). We also show that the GMAs cannot be pressure confined by the hot gas. Given the CO(2-1) linewidths of the GMAs (i.e., the velocity dispersion of the embedded GMCs) they should disperse on a timescale of about 12 Myr. No disk-like molecular structures are detected and all indications suggest that the molecular gas follows ballistic trajectories after condensing out of the thermally unstable hot gas. The 230 GHz luminosity of the central continuum source is 500 times greater than its low frequency radio luminosity and probably reflects a recent accretion event. The spectrum of the central continuum source also exhibits an absorption feature with a linewidth typical of an individual GMC and an infalling velocity of 250 km s{sup –1}.

  13. Chemical complexity in protoplanetary disks in the era of ALMA and Rosetta

    NASA Astrophysics Data System (ADS)

    Walsh, C.

    2016-05-01

    Comets provide a unique insight into the molecular composition and complexity of the material in the primordial solar nebula. Recent results from the Rosetta mission, currently monitoring comet 67P/Churyumov-Gerasimenko in situ, and ALMA (the Atacama Large Millimeter/submillimeter Array) have demonstrated a tantalising link between the chemical complexity now confirmed in disks (via the detection of gas-phase cf.CH3CN Öberg et al. [13]) and that confirmed on the surface of 67P (Goesmann et al. [3]), raising questions concerning the chemical origin of such species (cloud or inheritance versus disk synthesis). Results from an astrochemical model of a protoplanetary disk are presented in which complex chemistry is included and in which it is assumed that simple ices only are inherited from the parent molecular cloud. The model results show good agreement with the abundances of several COMs observed on the surface of 67P with Philae/COSAC. Cosmic-ray and X-ray-induced photoprocessing of predominantly simple ices inherited by the protoplanetary disk is sufficient to generate a chemical complexity similar to that observed in comets. This indicates that the icy COMs detected on the surface of 67P may have a disk origin. The results also show that gas-phase cf.CH3CN is abundant in the inner warm disk atmosphere where hot gas-phase chemistry dominates and potentially erases the ice chemical signature. Hence, cf.CH3CN may not be an unambiguous tracer of the complex organic ice reservoir. However, a better understanding of the hot gas-phase chemistry of cf.CH3CN is needed to confirm this preliminary conclusion.

  14. Debris Disks in the Scorpius-Centaurus OB Association Resolved by ALMA

    NASA Astrophysics Data System (ADS)

    Lieman-Sifry, Jesse; Hughes, A. Meredith; Carpenter, John M.; Gorti, Uma; Hales, Antonio; Flaherty, Kevin M.

    2016-09-01

    We present a CO(2-1) and 1240 μm continuum survey of 23 debris disks with spectral types B9-G1, observed at an angular resolution of 0.″5-1″ with the Atacama Large Millimeter/Submillimeter Array (ALMA). The sample was selected for large infrared excess and age ˜10 Myr, to characterize the prevalence of molecular gas emission in young debris disks. We identify three CO-rich debris disks, plus two additional tentative (3σ) CO detections. Twenty disks were detected in the continuum at the >3σ level. For the 12 disks in the sample that are spatially resolved by our observations, we perform an independent analysis of the interferometric continuum visibilities to constrain the basic dust disk geometry, as well as a simultaneous analysis of the visibilities and broadband spectral energy distribution to constrain the characteristic grain size and disk mass. The gas-rich debris disks exhibit preferentially larger outer radii in their dust disks, and a higher prevalence of characteristic grain sizes smaller than the blowout size. The gas-rich disks do not exhibit preferentially larger dust masses, contrary to expectations for a scenario in which a higher cometary destruction rate would be expected to result in a larger mass of both CO and dust. The three debris disks in our sample with strong CO detections are all around A stars: the conditions in disks around intermediate-mass stars appear to be the most conducive to the survival or formation of CO.

  15. ALMA Observations of Circumstellar Disks in the Upper Scorpius OB Association

    NASA Astrophysics Data System (ADS)

    Barenfeld, Scott A.; Carpenter, John M.; Ricci, Luca; Isella, Andrea

    2016-08-01

    We present ALMA observations of 106 G-, K-, and M-type stars in the Upper Scorpius OB Association hosting circumstellar disks. With these data, we measure the 0.88 mm continuum and 12CO J = 3-2 line fluxes of disks around low-mass (0.14-1.66 M ⊙) stars at an age of 5-11 Myr. Of the 75 primordial disks in the sample, 53 are detected in the dust continuum and 26 in CO. Of the 31 disks classified as debris/evolved transitional disks, five are detected in the continuum and none in CO. The lack of CO emission in approximately half of the disks with detected continuum emission can be explained if CO is optically thick but has a compact emitting area (≲40 au), or if the CO is heavily depleted by a factor of at least ˜1000 relative to interstellar medium abundances and is optically thin. The continuum measurements are used to estimate the dust mass of the disks. We find a correlation between disk dust mass and stellar host mass consistent with a power-law relation of {M}{dust}\\propto {M}* 1.67+/- 0.37. Disk dust masses in Upper Sco are compared to those measured in the younger Taurus star-forming region to constrain the evolution of disk dust mass. We find that the difference in the mean of {log}({M}{dust}/{M}* ) between Taurus and Upper Sco is 0.64 ± 0.09, such that M dust/M * is lower in Upper Sco by a factor of ˜4.5.

  16. ALMA Observations of Circumstellar Disks in the Upper Scorpius OB Association

    NASA Astrophysics Data System (ADS)

    Barenfeld, Scott A.; Carpenter, John M.; Ricci, Luca; Isella, Andrea

    2016-08-01

    We present ALMA observations of 106 G-, K-, and M-type stars in the Upper Scorpius OB Association hosting circumstellar disks. With these data, we measure the 0.88 mm continuum and 12CO J = 3–2 line fluxes of disks around low-mass (0.14–1.66 M ⊙) stars at an age of 5–11 Myr. Of the 75 primordial disks in the sample, 53 are detected in the dust continuum and 26 in CO. Of the 31 disks classified as debris/evolved transitional disks, five are detected in the continuum and none in CO. The lack of CO emission in approximately half of the disks with detected continuum emission can be explained if CO is optically thick but has a compact emitting area (≲40 au), or if the CO is heavily depleted by a factor of at least ˜1000 relative to interstellar medium abundances and is optically thin. The continuum measurements are used to estimate the dust mass of the disks. We find a correlation between disk dust mass and stellar host mass consistent with a power-law relation of {M}{dust}\\propto {M}* 1.67+/- 0.37. Disk dust masses in Upper Sco are compared to those measured in the younger Taurus star-forming region to constrain the evolution of disk dust mass. We find that the difference in the mean of {log}({M}{dust}/{M}* ) between Taurus and Upper Sco is 0.64 ± 0.09, such that M dust/M * is lower in Upper Sco by a factor of ˜4.5.

  17. ALMA IMAGING OF HCN, CS, AND DUST IN ARP 220 AND NGC 6240

    SciTech Connect

    Scoville, Nick; Manohar, Swarnima; Murchikova, Lena; Sheth, Kartik; Walter, Fabian; Zschaechner, Laura; Yun, Min; Koda, Jin; Sanders, David; Barnes, Joshua; Thompson, Todd; Robertson, Brant; Tacconi, Linda; Narayanan, Desika; Genzel, Reinhard; Davies, Richard; Hernquist, Lars; Brown, Robert; Hayward, Christopher C.; Kartaltepe, Jeyhan; and others

    2015-02-10

    We report ALMA Band 7 (350 GHz) imaging at 0.''4-0.''6 resolution and Band 9 (696 GHz) at ∼0.''25 resolution of the luminous IR galaxies Arp 220 and NGC 6240. The long wavelength dust continuum is used to estimate interstellar medium masses for Arp 220 east and west and NGC 6240 of 1.9, 4.2, and 1.6 × 10{sup 9} M {sub ☉}within radii of 69, 65, and 190 pc. The HCN emission was modeled to derive the emissivity distribution as a function of radius and the kinematics of each nuclear disk, yielding dynamical masses consistent with the masses and sizes derived from the dust emission. In Arp 220, the major dust and gas concentrations are at radii less than 50 pc in both counter-rotating nuclear disks. The thickness of the disks in Arp 220 estimated from the velocity dispersion and rotation velocities are 10-20 pc and the mean gas densities are n{sub H{sub 2}}∼10{sup 5} cm{sup –3} at R <50 pc. We develop an analytic treatment for the molecular excitation (including photon trapping), yielding volume densities for both the HCN and CS emission with n {sub H2} ∼ 2 × 10{sup 5} cm{sup –3}. The agreement of the mean density from the total mass and size with that required for excitation suggests that the volume is essentially filled with dense gas, i.e., it is not cloudy or like swiss cheese.

  18. A Keplerian disk around a Class 0 source: ALMA observations of VLA1623A

    NASA Astrophysics Data System (ADS)

    Murillo, Nadia M.; Lai, Shih-Ping; Bruderer, Simon; Harsono, Daniel; van Dishoeck, Ewine F.

    2013-12-01

    Context. Rotationally supported disks are critical in the star formation process. The questions of when they form and what factors influence or hinder their formation have been studied but are largely unanswered. Observations of early-stage YSOs are needed to probe disk formation. Aims: VLA1623 is a triple non-coeval protostellar system, with a weak magnetic field perpendicular to the outflow, whose Class 0 component, VLA1623A, shows a disk-like structure in continuum with signatures of rotation in line emission. We aim to determine whether this structure is in part or in whole a rotationally supported disk, i.e. a Keplerian disk, and what its characteristics are. Methods: ALMA Cycle 0 Early Science 1.3 mm continuum and C18O (2-1) observations in the extended configuration are presented here and used to perform an analysis of the disk-like structure using position-velocity (PV) diagrams and thin disk modeling with the addition of foreground absorption. Results: The PV diagrams of the C18O line emission suggest the presence of a rotationally supported component with a radius of at least 50 AU. Kinematical modeling of the line emission shows that the disk out to 180 AU is actually rotationally supported, with the rotation described well by Keplerian rotation out to at least 150 AU, and the central source mass is ~0.2 M⊙ for an inclination of 55°. Pure infall and conserved angular momentum rotation models are excluded. Conclusions: VLA1623A, a very young Class 0 source, presents a disk with an outer radius Rout = 180 AU with a Keplerian velocity structure out to at least 150 AU. The weak magnetic fields and recent fragmentation in this region of ρ Ophiuchus may have played a leading role in the formation of the disk. Appendices are available in electronic form at http://www.aanda.org

  19. CO GAS INSIDE THE PROTOPLANETARY DISK CAVITY IN HD 142527: DISK STRUCTURE FROM ALMA

    SciTech Connect

    Perez, S.; Casassus, S.; Van der Plas, G.; Christiaens, V.; Ménard, F.; Roman, P.; Cieza, L.; Hales, A. S.; Pinte, C.

    2015-01-10

    Inner cavities and annular gaps in circumstellar disks are possible signposts of giant planet formation. The young star HD 142527 hosts a massive protoplanetary disk with a large cavity that extends up to 140 AU from the central star, as seen in continuum images at infrared and millimeter wavelengths. Estimates of the survival of gas inside disk cavities are needed to discriminate between clearing scenarios. We present a spatially and spectrally resolved carbon monoxide isotopologue observations of the gas-rich disk HD 142527, in the J = 2-1 line of {sup 12}CO, {sup 13}CO, and C{sup 18}O obtained with the Atacama Large Millimeter/submillimeter Array (ALMA). We detect emission coming from inside the dust-depleted cavity in all three isotopologues. Based on our analysis of the gas in the dust cavity, the {sup 12}CO emission is optically thick, while {sup 13}CO and C{sup 18}O emissions are both optically thin. The total mass of residual gas inside the cavity is ∼1.5-2 M {sub Jup}. We model the gas with an axisymmetric disk model. Our best-fit model shows that the cavity radius is much smaller in CO than it is in millimeter continuum and scattered light observations, with a gas cavity that does not extend beyond 105 AU (at 3σ). The gap wall at its outer edge is diffuse and smooth in the gas distribution, while in dust continuum it is manifestly sharper. The inclination angle, as estimated from the high velocity channel maps, is 28 ± 0.5 deg, higher than in previous estimates, assuming a fix central star mass of 2.2 M {sub ☉}.

  20. ALMA observations of cold molecular gas filaments trailing rising radio bubbles in PKS 0745-191

    NASA Astrophysics Data System (ADS)

    Russell, H. R.; McNamara, B. R.; Fabian, A. C.; Nulsen, P. E. J.; Edge, A. C.; Combes, F.; Murray, N. W.; Parrish, I. J.; Salomé, P.; Sanders, J. S.; Baum, S. A.; Donahue, M.; Main, R. A.; O'Connell, R. W.; O'Dea, C. P.; Oonk, J. B. R.; Tremblay, G.; Vantyghem, A. N.; Voit, G. M.

    2016-05-01

    We present ALMA observations of the CO(1-0) and CO(3-2) line emission tracing filaments of cold molecular gas in the central galaxy of the cluster PKS 0745-191. The total molecular gas mass of 4.6± 0.3× 109 M_{⊙}, assuming a Galactic XCO factor, is divided roughly equally between three filaments each extending radially 3-5 kpc from the galaxy centre. The emission peak is located in the SE filament ˜ 1 arcsec (2 kpc) from the nucleus. The velocities of the molecular clouds in the filaments are low, lying within ± 100 { km s^{-1}} of the galaxy's systemic velocity. Their full width at half-maximum (FWHM) are less than 150 { km s^{-1},} which is significantly below the stellar velocity dispersion. Although the molecular mass of each filament is comparable to a rich spiral galaxy, such low velocities show that the filaments are transient and the clouds would disperse on < 107 yr time-scales unless supported, likely by the indirect effect of magnetic fields. The velocity structure is inconsistent with a merger origin or gravitational free-fall of cooling gas in this massive central galaxy. If the molecular clouds originated in gas cooling even a few kpc from their current locations their velocities would exceed those observed. Instead, the projection of the N and SE filaments underneath X-ray cavities suggests they formed in the updraft behind bubbles buoyantly rising through the cluster atmosphere. Direct uplift of the dense gas by the radio bubbles appears to require an implausibly high coupling efficiency. The filaments are coincident with low temperature X-ray gas, bright optical line emission and dust lanes indicating that the molecular gas could have formed from lifted warmer gas that cooled in situ.

  1. THE PECULIAR DISTRIBUTION OF CH{sub 3}CN IN IRC +10216 SEEN BY ALMA

    SciTech Connect

    Agúndez, M.; Cernicharo, J.; Quintana-Lacaci, G.; Prieto, L. Velilla; Marcelino, N.

    2015-12-01

    IRC +10216 is a circumstellar envelope around a carbon-rich evolved star which contains a large variety of molecules. According to interferometric observations, molecules are distributed either concentrated around the central star or as a hollow shell with a radius of ∼15″. We present ALMA Cycle 0 band 6 observations of the J = 14 – 13 rotational transition of CH{sub 3}CN in IRC +10216, obtained with an angular resolution of 0.″76 × 0.″61. The bulk of the emission is distributed as a hollow shell located at just ∼2″ from the star, with a void of emission in the central region up to a radius of ∼1″. This spatial distribution is markedly different from those found to date in this source for other molecules. Our analysis indicates that methyl cyanide is not formed in either the stellar photosphere or far in the outer envelope, but at radial distances as short as 1″–2″, reaching a maximum abundance of ∼0.02 molecules cm{sup −3} at 2″ from the star. Standard chemical models of IRC +10216 predict that the bulk of CH{sub 3}CN molecules should be present at a radius of ∼15″ where other species such as polyyne radicals and cyanopolyynes are observed, with an additional inner component within 1″ from the star. The non-uniform structure of the circumstellar envelope and grain surface processes are discussed as possible causes of the peculiar distribution of methyl cyanide in IRC +10216.

  2. SPIRAL ARMS IN THE DISK OF HD 142527 FROM CO EMISSION LINES WITH ALMA

    SciTech Connect

    Christiaens, V.; Casassus, S.; Perez, S.; Van der Plas, G.; Ménard, F.

    2014-04-10

    In view of both the size of its gap and the previously reported asymmetries and near-infrared spiral arms, the transition disk of the Herbig Fe star HD 142527 constitutes a remarkable case study. This paper focuses on the morphology of the outer disk through ALMA observations of {sup 12}CO J = 2-1, {sup 12}CO J = 3-2, and {sup 13}CO J = 2-1. Both {sup 12}CO J = 2-1 and {sup 12}CO J = 3-2 show spiral features of different sizes. The innermost spiral arm (S1) is a radio counterpart of the first near-infrared spiral observed by Fukagawa, but it is shifted radially outward. However, the most conspicuous CO spiral arm (S2) lies at the outskirts of the disk and has not been detected before. It corresponds to a cold density structure, with both brightness and excitation temperatures of order 13±2 K and conspicuous in the {sup 12}CO J = 2-1 peak-intensity map, but faint in {sup 12}CO J = 3-2. There is also a faint counterarm (S3), at a point-symmetric location of S2 with respect to the star. These three spirals are modeled separately with two different formulae that approximate the loci of density maxima in acoustic waves due to embedded planets. S1 could be fit relatively well with these formulae, compared to S2 and S3. Alternative scenarios such as gravitational instability or external tidal interaction are discussed. The impact of channelization on spectrally and spatially resolved peak intensity maps is also briefly addressed.

  3. Sub-mm free-free emission from the winds of massive stars in the age of ALMA

    NASA Astrophysics Data System (ADS)

    Daley-Yates, S.; Stevens, I. R.; Crossland, T. D.

    2016-09-01

    The thermal radio and sub-mm emission from the winds of massive stars is investigated and the contribution to the emission due to the stellar wind acceleration region and clumping of the wind is quantified. Building upon established theory, a method for calculating the thermal radio and sub-mm emission using results for a line-driven stellar outflow according to Castor, Abbott & Klein (1975) is presented. The results show strong variation of the spectral index for 102 GHz <ν < 104 GHz. This corresponds both to the wind acceleration region and clumping of the wind, leading to a strong dependence on the wind velocity law and clumping parameters. The Atacama Large Millimeter/sub-mm Array (ALMA) is the first observatory to have both the spectral window and sensitivity to observe at the high frequencies required to probe the acceleration regions of massive stars. The deviations in the predicted flux levels as a result of the inclusion of the wind acceleration region and clumping are sufficient to be detected by ALMA, through deviations in the spectral index in different portions of the radio/sub-mm spectra of massive stars, for a range of reasonable mass-loss rates and distances. Consequently both mechanisms need to be included to fully understand the mass-loss rates of massive stars.

  4. ALMA observations of the submillimetre hydrogen recombination line from the type 2 active nucleus of NGC 1068

    NASA Astrophysics Data System (ADS)

    Izumi, Takuma; Nakanishi, Kouichiro; Imanishi, Masatoshi; Kohno, Kotaro

    2016-07-01

    Hydrogen recombination lines at the submillimetre band (submm-RLs) can serve as probes of ionized gas without dust extinction. One therefore expects to probe the broad-line region (BLR) of an obscured (type 2) active galactic nucleus (AGN) with those lines. However, admitting the large uncertainty in the continuum level, here we report on the non-detection of both broad and narrow H26 α emission line (rest frequency = 353.62 GHz) towards the prototypical type 2 AGN of NGC 1068 with the Atacama Large Millimeter/submillimeter Array (ALMA). We also investigate the nature of BLR clouds that can potentially emit submm-RLs with model calculations. As a result, we suggest that clouds with an electron density (Ne) of ˜109 cm-3 can mainly contribute to broad submm-RLs in terms of the line flux. On the other hand, line flux from other density clouds would be insignificant considering their too large or too small line optical depths. However, even for the case of Ne ˜ 109 cm-3 clouds, we also suggest that the expected line flux is extremely low, which is impractical to detect even with ALMA.

  5. An analysis of a preliminary ALMA Orion KL spectrum via the use of complete experimental spectra from the laboratory

    NASA Astrophysics Data System (ADS)

    Fortman, Sarah M.; McMillan, James P.; Neese, Christopher F.; Randall, Suzanna K.; Remijan, Anthony J.; Wilson, T. L.; De Lucia, Frank C.

    2012-10-01

    Preliminary Atacama Large Millimeter/Submillimeter Array (ALMA) science verification data for a single pixel centered on the hot core of Orion KL (R. A. = 05 h 35 m 14.35 s, Dec = -05°22'35″ (J2000)) are available as this special issue on broadband spectroscopy is coming to press. As part of this verification process it is useful to compare simulations based on laboratory spectroscopy with ALMA results. This provides not only a test of instrumentation and analysis, but also a test of astrophysical assumptions such as local thermodynamic equilibrium (LTE) and the temperature variations within telescope beams. However, these tests are spectroscopically limited because it is well known that astrophysical spectra contain large numbers of unknown lines, many of which are presumably due to unanalyzed rotational spectra in excited vibrational states of a relatively few molecules. To address this issue we have previously discussed the use of broadband complete experimental spectra (CES) that is obtained from the analysis of several hundred intensity calibrated spectra taken over a range of temperatures. In this paper we will compare these CES with the similarly complete astrophysical spectra.

  6. ALMA observations of the vibrationally excited rotational CO transitionv= 1,J= 3 - 2 towards five AGB stars

    NASA Astrophysics Data System (ADS)

    Khouri, T.; Vlemmings, W. H. T.; Ramstedt, S.; Lombaert, R.; Maercker, M.; De Beck, E.

    2016-11-01

    We report the serendipitous detection with ALMA of the vibrationally-excited pure-rotational CO transition $v=1, J=3-2$ towards five asymptotic giant branch (AGB) stars, $o$ Cet, R Aqr, R Scl, W Aql, and $\\pi^1$ Gru. The observed lines are formed in the poorly-understood region located between the stellar surface and the region where the wind starts, the so-called warm molecular layer. We successfully reproduce the observed lines profiles using a simple model. We constrain the extents, densities, and kinematics of the region where the lines are produced. R Aqr and R Scl show inverse P-Cygni line profiles which indicate infall of material onto the stars. The line profiles of $o$ Cet and R Scl show variability. The serendipitous detection towards these five sources shows that vibrationally-excited rotational lines can be observed towards a large number of nearby AGB stars using ALMA. This opens a new possibility for the study of the innermost regions of AGB circumstellar envelopes.

  7. Measurement of the Black Hole Mass in NGC 1332 from ALMA Observations at 0.044 arcsecond Resolution

    NASA Astrophysics Data System (ADS)

    Barth, Aaron J.; Boizelle, Benjamin D.; Darling, Jeremy; Baker, Andrew J.; Buote, David A.; Ho, Luis C.; Walsh, Jonelle L.

    2016-05-01

    We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 3 observations of CO(2–1) emission from the circumnuclear disk in the E/S0 galaxy NGC 1332 at 0.″044 resolution. The disk exhibits regular rotational kinematics and central high-velocity emission (±500 km s‑1) consistent with the presence of a compact central mass. We construct models for a thin, dynamically cold disk in the gravitational potential of the host galaxy and black hole and fit the beam-smeared model line profiles directly to the ALMA data cube. Model fits successfully reproduce the disk kinematics out to r = 200 pc. Fitting models just to spatial pixels within projected r = 50 pc of the nucleus (two times larger than the black hole’s gravitational radius of influence), we find {M}{BH}=({6.64}-0.63+0.65)× {10}8 {M}ȯ . This observation demonstrates ALMA’s powerful capability to determine the masses of supermassive black holes by resolving gas kinematics on small angular scales in galaxy nuclei.

  8. Installation and verification of high precision mechanics in concrete structures at the example of ALMA antenna interfaces

    NASA Astrophysics Data System (ADS)

    Heinz, Volker; Kraus, Max; Orellana, Eduardo

    2012-09-01

    For the ALMA interferometer at the array operation facility near San Pedro de Atacama at 5.000 meters asl 192 concrete antenna foundations had to be equipped with coupling points for 66 antennas. These antennas will be frequently moved between the foundations and placed on these interfaces without further adjustment. To position the ALMA antennas with the required accuracy, high precision inserts need to be installed in previously casted concrete foundations. Very tight mechanical tolerances have to be applied to civil structures, with standard tolerances of not less than millimeters. This is extremely difficult considering the material (mortar and steel in a concrete slab) to be used and the environmental conditions on site. Special tools had to be designed and an installation and alignment procedure developed, tested and improved. Important was to have a robust process, which allows highest precision installation without major re-machining for approx 600 interface blocks. Installation material, which could cope with the conditions, was specially tested for these requirements. The geometry of the interface and other parameters such as horizontal and vertical stiffness must be verified after the installation. Special metrology tools to measure reliable at micron level at high altitude had been selected. The experience and knowledge acquired will be beneficial for the installation of any opto-mechanical device in civil engineering structures, such as telescope and dome track rails, but also in optical interferometer installations. Metrology requirements and environmental conditions in most of these cases are equally challenging.

  9. ALMA FOLLOWS STREAMING OF DENSE GAS DOWN TO 40 pc FROM THE SUPERMASSIVE BLACK HOLE IN NGC 1097

    SciTech Connect

    Fathi, Kambiz; Pinol-Ferrer, Nuria; Lundgren, Andreas A.; Wiklind, Tommy; Kohno, Kotaro; Izumi, Takuma; Martin, Sergio; Espada, Daniel; Hatziminaoglou, Evanthia; Imanishi, Masatoshi; Krips, Melanie; Matsushita, Satoki; Meier, David S.; Nakai, Naomasa; Sheth, Kartik; Turner, Jean; Van de Ven, Glenn

    2013-06-20

    We present a kinematic analysis of the dense molecular gas in the central 200 pc of the nearby galaxy NGC 1097, based on Cycle 0 observations with the Atacama Large Millimeter/submillimeter Array (ALMA). We use the HCN(4-3) line to trace the densest interstellar molecular gas (n{sub H{sub 2}}{approx}10{sup 8} cm{sup -3}), and quantify its kinematics, and estimate an inflow rate for the molecular gas. We find a striking similarity between the ALMA kinematic data and the analytic spiral inflow model that we have previously constructed based on ionized gas velocity fields on larger scales. We are able to follow dense gas streaming down to 40 pc distance from the supermassive black hole in this Seyfert 1 galaxy. In order to fulfill marginal stability, we deduce that the dense gas is confined to a very thin disk, and we derive a dense gas inflow rate of 0.09 M{sub Sun} yr{sup -1} at 40 pc radius. Combined with previous values from the H{alpha} and CO gas, we calculate a combined molecular and ionized gas inflow rate of {approx}0.2 M{sub Sun} yr{sup -1} at 40 pc distance from the central supermassive black hole of NGC 1097.

  10. Star formation and feedback in LMC Massive Clusters: ALMA and HST analysis of 30 Doradus and N159

    NASA Astrophysics Data System (ADS)

    Indebetouw, Remy

    2015-08-01

    The Magellanic Clouds offer the opportunity to study star formation at reduced metallicity with no distance ambiguity and minimal line-of-sight confusion. They are arguably unique in that it is observationally tractable to analyze entire galaxies (e.g. our surveys with Spitzer and Herschel) simultaneously with critical subparsec physics, especially using ALMA and HST (1"~0.25pc). I will discuss the effects of the massive cluster R136 on star formation within 100pc in 30 Doradus, and on the formation of new star clusters in N159, a separate region 600pc to the south. These represent two different evolutionary states: 30 Doradus a more evolved cluster in which current star formation has potentially been significantly affected by the previous generations, and N159 a significantly younger region in which massive clusters may still form in the future. Cluster-forming clumps near R136 analyzed with ALMA contain both massive YSOs and low-mass pre-main-sequence stars revealed by HST. Although diffuse molecular gas is photodissociated, the cluster-forming clumps do not have dramatically different properties from parsec-sized clumps in less active Milky Way regions. Cluster-forming clumps and filaments in N159 also contain a rich pre-main-sequence population which we can now relate to the clump-scale dense gas distribution.

  11. Star formation and feedback in the LMC: ALMA and HST analysis of 30 Doradus and N159

    NASA Astrophysics Data System (ADS)

    Indebetouw, Remy

    2015-08-01

    The Magellanic Clouds offer the opportunity to study star formation at reduced metallicity with no distance ambiguity and minimal line-of-sight confusion. They are arguably unique in that it is observationally tractable to analyze entire galaxies (e.g. our surveys with Spitzer and Herschel) simultaneously with critical subparsec physics, especially using ALMA and HST (1"~0.25pc). I will discuss the effects of the massive cluster R136 on star formation within 100pc in 30 Doradus, and on the formation of new star clusters in N159, a separate region 600pc to the south. These represent two different evolutionary states: 30 Doradus a more evolved cluster in which current star formation has potentially been significantly affected by the previous generations, and N159 a significantly younger region in which massive clusters may still form in the future. Cluster-forming clumps near R136 analyzed with ALMA contain both massive YSOs and low-mass pre-main-sequence stars revealed by HST. Although diffuse molecular gas is photodissociated, the cluster-forming clumps do not have dramatically different properties from parsec-sized clumps in less active Milky Way regions. Cluster-forming clumps and filaments in N159 also contain a rich pre-main-sequence population which we can now relate to the clump-scale dense gas distribution.

  12. ALMA-resolved salt emission traces the chemical footprint and inner wind morphology of VY Canis Majoris

    NASA Astrophysics Data System (ADS)

    Decin, L.; Richards, A. M. S.; Millar, T. J.; Baudry, A.; De Beck, E.; Homan, W.; Smith, N.; Van de Sande, M.; Walsh, C.

    2016-07-01

    Context. At the end of their lives, most stars lose a significant amount of mass through a stellar wind. The specific physical and chemical circumstances that lead to the onset of the stellar wind for cool luminous stars are not yet understood. Complex geometrical morphologies in the circumstellar envelopes prove that various dynamical and chemical processes are interlocked and that their relative contributions are not easy to disentangle. Aims: We aim to study the inner-wind structure (R< 250 R⋆) of the well-known red supergiant VY CMa, the archetype for the class of luminous red supergiant stars experiencing high mass loss. Specifically, the objective is to unravel the density structure in the inner envelope and to examine the chemical interaction between gas and dust species. Methods: We analyse high spatial resolution (~0.̋24×0.̋13) ALMA science verification (SV) data in band 7, in which four thermal emission lines of gaseous sodium chloride (NaCl) are present at high signal-to-noise ratio. Results: For the first time, the NaCl emission in the inner wind region of VY CMa is spatially resolved. The ALMA observations reveal the contribution of up to four different spatial regions. The NaCl emission pattern is different compared to the dust continuum and TiO2 emission already analysed from the ALMA SV data. The emission can be reconciled with an axisymmetric geometry, where the lower density polar/rotation axis has a position angle of ~50° measured from north to east. However, this picture cannot capture the full morphological diversity, and discrete mass ejection events need to be invoked to explain localized higher-density regions. The velocity traced by the gaseous NaCl line profiles is significantly lower than the average wind terminal velocity, and much slower than some of the fastest mass ejections, signalling a wide range of characteristic speeds for the mass loss. Gaseous NaCl is detected far beyond the main dust condensation region. Realising the

  13. ALMA Survey of Lupus Protoplanetary Disks. I. Dust and Gas Masses

    NASA Astrophysics Data System (ADS)

    Ansdell, M.; Williams, J. P.; van der Marel, N.; Carpenter, J. M.; Guidi, G.; Hogerheijde, M.; Mathews, G. S.; Manara, C. F.; Miotello, A.; Natta, A.; Oliveira, I.; Tazzari, M.; Testi, L.; van Dishoeck, E. F.; van Terwisga, S. E.

    2016-09-01

    We present the first high-resolution sub-millimeter survey of both dust and gas for a large population of protoplanetary disks. Characterizing fundamental properties of protoplanetary disks on a statistical level is critical to understanding how disks evolve into the diverse exoplanet population. We use the Atacama Large Millimeter/Submillimeter Array (ALMA) to survey 89 protoplanetary disks around stars with {M}* \\gt 0.1 {M}ȯ in the young (1–3 Myr), nearby (150–200 pc) Lupus complex. Our observations cover the 890 μm continuum and the 13CO and C18O 3–2 lines. We use the sub-millimeter continuum to constrain {M}{{dust}} to a few Martian masses (0.2–0.4 M ⊕) and the CO isotopologue lines to constrain {M}{{gas}} to roughly a Jupiter mass (assuming an interstellar medium (ISM)-like [{CO}]/[{{{H}}}2] abundance). Of 89 sources, we detect 62 in continuum, 36 in 13CO, and 11 in C18O at \\gt 3σ significance. Stacking individually undetected sources limits their average dust mass to ≲ 6 Lunar masses (0.03 M ⊕), indicating rapid evolution once disk clearing begins. We find a positive correlation between {M}{{dust}} and M *, and present the first evidence for a positive correlation between {M}{{gas}} and M *, which may explain the dependence of giant planet frequency on host star mass. The mean dust mass in Lupus is 3× higher than in Upper Sco, while the dust mass distributions in Lupus and Taurus are statistically indistinguishable. Most detected disks have {M}{{gas}}≲ 1 {M}{{Jup}} and gas-to-dust ratios \\lt 100, assuming an ISM-like [{CO}]/[{{{H}}}2] abundance; unless CO is very depleted, the inferred gas depletion indicates that planet formation is well underway by a few Myr and may explain the unexpected prevalence of super-Earths in the exoplanet population.

  14. Measures of galaxy dust and gas mass with Herschel photometry and prospects for ALMA

    NASA Astrophysics Data System (ADS)

    Berta, S.; Lutz, D.; Genzel, R.; Förster-Schreiber, N. M.; Tacconi, L. J.

    2016-03-01

    Combining the deepest Herschel extragalactic surveys (PEP, GOODS-H, HerMES), and Monte Carlo mock catalogs, we explore the robustness of dust mass estimates based on modeling of broadband spectral energy distributions (SEDs) with two popular approaches: Draine & Li (2007, ApJ, 657, 810; DL07) and a modified blackbody (MBB). We analyze the cause, drivers, and trends of uncertainties and systematics in thorough detail. As long as the observed SED extends to at least 160-200 μm in the rest frame, Mdust can be recovered with a >3σ significance and without the occurrence of systematics. An average offset of a factor ~1.5 exists between DL07- and MBB-based dust masses, based on consistent dust properties. The performance of DL07 modeling turns out to be more robust than that of MBB since relative errors on Mdust are more mildly dependent on the maximum covered rest-frame wavelength and are less scattered. At the depth of the deepest Herschel surveys (in the GOODS-S field), it is possible to retrieve dust masses with a signal-to-noise ratio, S/N ≥ 3 for galaxies on the main sequence of star formation (MS) down to M∗ ~ 1010 [M⊙] up to z ~ 1. At higher redshift (z ≤ 2), the same result is only achieved for objects at the tip of the MS or for those objects lying above the tip owing to sensitivity and wavelength coverage limitations. Molecular gas masses, obtained by converting Mdust through the metallicity-dependent gas-to-dust ratio δGDR, are consistent with those based on the scaling of depletion time, τdep, and on CO sub-mm spectroscopy. Focusing on CO-detected galaxies at z> 1, the δGDR dependence on metallicity is consistent with the local relation, provided that a sufficient SED coverage is available. Once we established that Herschel-only and sub-mm-only estimates of dust masses can be affected by large uncertainties and possibly systematics in some cases, we combined far-IR Herschel data and sub-mm ALMA expected fluxes to study the advantages of a full

  15. ALMA Survey of Lupus Protoplanetary Disks. I. Dust and Gas Masses

    NASA Astrophysics Data System (ADS)

    Ansdell, M.; Williams, J. P.; van der Marel, N.; Carpenter, J. M.; Guidi, G.; Hogerheijde, M.; Mathews, G. S.; Manara, C. F.; Miotello, A.; Natta, A.; Oliveira, I.; Tazzari, M.; Testi, L.; van Dishoeck, E. F.; van Terwisga, S. E.

    2016-09-01

    We present the first high-resolution sub-millimeter survey of both dust and gas for a large population of protoplanetary disks. Characterizing fundamental properties of protoplanetary disks on a statistical level is critical to understanding how disks evolve into the diverse exoplanet population. We use the Atacama Large Millimeter/Submillimeter Array (ALMA) to survey 89 protoplanetary disks around stars with {M}* \\gt 0.1 {M}⊙ in the young (1-3 Myr), nearby (150-200 pc) Lupus complex. Our observations cover the 890 μm continuum and the 13CO and C18O 3-2 lines. We use the sub-millimeter continuum to constrain {M}{{dust}} to a few Martian masses (0.2-0.4 M ⊕) and the CO isotopologue lines to constrain {M}{{gas}} to roughly a Jupiter mass (assuming an interstellar medium (ISM)-like [{CO}]/[{{{H}}}2] abundance). Of 89 sources, we detect 62 in continuum, 36 in 13CO, and 11 in C18O at \\gt 3σ significance. Stacking individually undetected sources limits their average dust mass to ≲ 6 Lunar masses (0.03 M ⊕), indicating rapid evolution once disk clearing begins. We find a positive correlation between {M}{{dust}} and M *, and present the first evidence for a positive correlation between {M}{{gas}} and M *, which may explain the dependence of giant planet frequency on host star mass. The mean dust mass in Lupus is 3× higher than in Upper Sco, while the dust mass distributions in Lupus and Taurus are statistically indistinguishable. Most detected disks have {M}{{gas}}≲ 1 {M}{{Jup}} and gas-to-dust ratios \\lt 100, assuming an ISM-like [{CO}]/[{{{H}}}2] abundance; unless CO is very depleted, the inferred gas depletion indicates that planet formation is well underway by a few Myr and may explain the unexpected prevalence of super-Earths in the exoplanet population.

  16. Giant molecular clouds in the Large Magellanic Cloud seen in sub-parsec scales by ALMA

    NASA Astrophysics Data System (ADS)

    Kawamura, Akiko; Onishi, Toshikazu; Harada, Ryohei; Morioka, Yuuki; Tokuda, Kazuki; Meixner, Margaret; Indebetouw, Remy; Sewilo, Marta; Nayak, Omnarayani; Saigo, Kazuya; Fukui, Yasuo

    2015-08-01

    Stars are formed in dense clumps of giant molecular clouds (GMCs), and kinetic energy and heavy elements are ejected from stars back into the interstellar medium through stellar winds and supernova explosions. This cycle drives the evolution of galaxies and thus, it is important to understand GMC evolution and star formation activities to obtain deeper knowledge of galaxy evolution.The Large Magellanic Cloud (LMC) offers an ideal laboratory to study how the interstellar medium evolves and how stars are formed throughout a galaxy at an unrivaled closeness to us with its nearly face-on view. It is known that young populous clusters like R136 are still being formed, making it possible to study also populous cluster formation, which is not currently observed in the Galaxy. We conducted a survey of the GMCs in the LMC by NANTEN and classified them into three types according to the activities of massive star formation, corresponding the evolutional sequence of the GMCs. One of the features of the GMCs in the LMC is that there are a large number of GMCs without active massive star formation unlike those of the Galaxy. Thus, the LMC is one of the most suitable galaxies to study the evolution of GMCs by investigating the star formation and natal GMCs with various star formation activities.We have started to obtain ALMA data of molecular cloud distributions in CO lines with sub-parsec to parsec scales for different types of GMCs, for example, one of the most active on-going star forming regions, N159 E/W, cluster forming GMCs like N206, and without active massive star formation, GMC 225, etc. The detailed studies of 13CO(2-1) observations, for e.g. in N159 West, show that many filaments are straight or curved distributions with a typical width of 0.5-1.0 pc and a length of 5-10 pc. N159W-S located toward an intersection of two filaments, where we also detected molecular outflows, we set up a hypothesis that the two filaments collided with each other ˜105 yrs ago and

  17. Formation of Circumstellar Dust Around an Oxygen-Rich AGB Star W Hya: AlO and SiO Observations with ALMA

    NASA Astrophysics Data System (ADS)

    Takigawa, A.; Kamizuka, T.; Tachibana, S.; Yamamura, I.

    2016-08-01

    In order to understand the formation of circumstellar dust and the origin of presolar grains, we observed spatial distributions of AlO and SiO molecules around an oxygen-rich AGB star, W Hya, with ALMA (cycle 3).

  18. Band-9 ALMA Observations of the [N II] 122 μm Line and FIR Continuum in Two High-z Galaxies.

    NASA Astrophysics Data System (ADS)

    Ferkinhoff, Carl; Brisbin, Drew; Nikola, Thomas; Stacey, Gordon J.; Sheth, Kartik; Hailey-Dunsheath, Steve; Falgarone, Edith

    2015-06-01

    We present Atacama Large Millimeter Array (ALMA) observations of two high-redshift systems (SMMJ02399-0136 at z1 ˜ 2.8 and the Cloverleaf QSO at z1 ˜ 2.5) in their rest-frame 122 μm continuum (νsky ˜ 650 GHz, λsky ˜ 450 μm) and [N ii] 122 μm line emission. The continuum observations with a synthesized beam of ˜0.″ 25 resolve both sources and recover the expected flux. The Cloverleaf is resolved into a partial Einstein ring, while SMMJ02399-0136 is unambiguously separated into two components: a point source associated with an active galactic nucleus and an extended region at the location of a previously identified dusty starburst. We detect the [N ii] line in both systems, though significantly weaker than our previous detections made with the first generation z (Redshift) and Early Universe Spectrometer. We show that this discrepancy is mostly explained if the line flux is resolved out due to significantly more extended emission and longer ALMA baselines than expected. Based on the ALMA observations we determine that ≥75% of the total [N ii] line flux in each source is produced via star formation. We use the [N ii] line flux that is recovered by ALMA to constrain the N/H abundance, ionized gas mass, hydrogen- ionizing photon rate, and star formation rate. In SMMJ02399-0136 we discover it contains a significant amount (˜1000 M⊙ yr-1) of unobscured star formation in addition to its dusty starburst and argue that SMMJ02399-0136 may be similar to the Antennae Galaxies (Arp 244) locally. In total these observations provide a new look at two well-studied systems while demonstrating the power and challenges of Band-9 ALMA observations of high-z systems.

  19. BAND-9 ALMA OBSERVATIONS OF THE [N II] 122 μm LINE AND FIR CONTINUUM IN TWO HIGH-z GALAXIES

    SciTech Connect

    Ferkinhoff, Carl; Brisbin, Drew; Stacey, Gordon J.; Nikola, Thomas; Sheth, Kartik; Hailey-Dunsheath, Steve; Falgarone, Edith

    2015-06-20

    We present Atacama Large Millimeter Array (ALMA) observations of two high-redshift systems (SMMJ02399-0136 at z{sub 1} ∼ 2.8 and the Cloverleaf QSO at z{sub 1} ∼ 2.5) in their rest-frame 122 μm continuum (ν{sub sky} ∼ 650 GHz, λ{sub sky} ∼ 450 μm) and [N ii] 122 μm line emission. The continuum observations with a synthesized beam of ∼0.″ 25 resolve both sources and recover the expected flux. The Cloverleaf is resolved into a partial Einstein ring, while SMMJ02399-0136 is unambiguously separated into two components: a point source associated with an active galactic nucleus and an extended region at the location of a previously identified dusty starburst. We detect the [N ii] line in both systems, though significantly weaker than our previous detections made with the first generation z (Redshift) and Early Universe Spectrometer. We show that this discrepancy is mostly explained if the line flux is resolved out due to significantly more extended emission and longer ALMA baselines than expected. Based on the ALMA observations we determine that ≥75% of the total [N ii] line flux in each source is produced via star formation. We use the [N ii] line flux that is recovered by ALMA to constrain the N/H abundance, ionized gas mass, hydrogen- ionizing photon rate, and star formation rate. In SMMJ02399-0136 we discover it contains a significant amount (∼1000 M{sub ⊙} yr{sup −1}) of unobscured star formation in addition to its dusty starburst and argue that SMMJ02399-0136 may be similar to the Antennae Galaxies (Arp 244) locally. In total these observations provide a new look at two well-studied systems while demonstrating the power and challenges of Band-9 ALMA observations of high-z systems.

  20. ALMA observations of a z ≈ 3.1 protocluster: star formation from active galactic nuclei and Lyman-alpha blobs in an overdense environment

    NASA Astrophysics Data System (ADS)

    Alexander, D. M.; Simpson, J. M.; Harrison, C. M.; Mullaney, J. R.; Smail, I.; Geach, J. E.; Hickox, R. C.; Hine, N. K.; Karim, A.; Kubo, M.; Lehmer, B. D.; Matsuda, Y.; Rosario, D. J.; Stanley, F.; Swinbank, A. M.; Umehata, H.; Yamada, T.

    2016-09-01

    We exploit Atacama Large Interferometer Array (ALMA) 870 μm observations to measure the star formation rates (SFRs) of eight X-ray detected active galactic nuclei (AGNs) in a z ≈ 3.1 protocluster, four of which reside in extended Lyα haloes (often termed Lyman-alpha blobs: LABs). Three of the AGNs are detected by ALMA and have implied SFRs of ≈220-410 M⊙ yr-1; the non-detection of the other five AGNs places SFR upper limits of ≲210 M⊙ yr-1. The mean SFR of the protocluster AGNs (≈110-210 M⊙ yr-1) is consistent (within a factor of ≈0.7-2.3) with that found for co-eval AGNs in the field, implying that the galaxy growth is not significantly accelerated in these systems. However, when also considering ALMA data from the literature, we find evidence for elevated mean SFRs (up-to a factor of ≈5.9 over the field) for AGNs at the protocluster core, indicating that galaxy growth is significantly accelerated in the central regions of the protocluster. We also show that all of the four protocluster LABs are associated with an ALMA counterpart within the extent of their Lyα emission. The SFRs of the ALMA sources within the LABs (≈150-410 M⊙ yr-1) are consistent with those expected for co-eval massive star-forming galaxies in the field. Furthermore, the two giant LABs (with physical extents of ≳100 kpc) do not host more luminous star formation than the smaller LABs, despite being an order of magnitude brighter in Lyα emission. We use these results to discuss star formation as the power source of LABs.

  1. Agreement between the Government of the Republic of Chile and ESO for Establishing a New Center for Observation in Chile - ALMA

    NASA Astrophysics Data System (ADS)

    2002-10-01

    On October 21, 2002, the Minister of Foreign Affairs of the Republic of Chile, Mrs. María Soledad Alvear and the ESO Director General, Dr. Catherine Cesarsky , signed an Agreement that authorizes ESO to establish a new center for astronomical observation in Chile . This new center for astronomical observation will be for the Atacama Large Millimeter Array (ALMA) , the largest ground based astronomical project for the next decades. On this occasion, Minister Alvear stated that "we want to have ALMA working as soon as possible, which will constitute a pride not only to Chilean scientists but for the whole country and in particular, for the community of the Antofagasta Region" . ESO Director General Cesarsky said that "signing this agreement between the Government of Chile and ESO is a historical step in the astronomical collaboration between Chile and ESO and it will allow Chile to host, once again, a project of worldwide interest and impact" . ALMA is a joint project on equal basis between ESO and AUI (Associated Universities, Inc.). These organizations represent the scientific interests of Europe on one side and the United States with Canada on the other side. Chilean astronomers are closely involved with the project and 10% of the observing time will be reserved for Chilean science. ALMA will be built in the Andes, on the Plateau of Chajnantor (see the Chajnantor Photo Gallery ), 5000 metres above sea level and 60 km East of the town of San Pedro de Atacama. The array will be comprised of 64 antennas with unprecedent sensitivity and angular resolution that will allow studying the origin of galaxies, stars and planets, opening new horizons for astronomy, and being able to observe galaxies across the universe where stars are being formed. The agreement now signed between ESO and the Government of the Republic of Chile recognizes the interest that the ALMA Project has for Chile, as it will deepen and strengthen the cooperation in scientific and technological matters

  2. Faint submillimeter galaxies revealed by multifield deep ALMA observations: number counts, spatial clustering, and a dark submillimeter line emitter

    SciTech Connect

    Ono, Yoshiaki; Ouchi, Masami; Momose, Rieko; Kurono, Yasutaka

    2014-11-01

    We present the statistics of faint submillimeter/millimeter galaxies (SMGs) and serendipitous detections of a submillimeter/millimeter line emitter (SLE) with no multi-wavelength continuum counterpart revealed by the deep ALMA observations. We identify faint SMGs with flux densities of 0.1-1.0 mJy in the deep Band-6 and Band-7 maps of 10 independent fields that reduce cosmic variance effects. The differential number counts at 1.2 mm are found to increase with decreasing flux density down to 0.1 mJy. Our number counts indicate that the faint (0.1-1.0 mJy, or SFR{sub IR} ∼ 30-300 M {sub ☉} yr{sup –1}) SMGs contribute nearly a half of the extragalactic background light (EBL), while the remaining half of the EBL is mostly contributed by very faint sources with flux densities of <0.1 mJy (SFR{sub IR} ≲ 30 M {sub ☉} yr{sup –1}). We conduct counts-in-cells analysis with multifield ALMA data for the faint SMGs, and obtain a coarse estimate of galaxy bias, b {sub g} < 4. The galaxy bias suggests that the dark halo masses of the faint SMGs are ≲ 7 × 10{sup 12} M {sub ☉}, which is smaller than those of bright (>1 mJy) SMGs, but consistent with abundant high-z star-forming populations, such as sBzKs, LBGs, and LAEs. Finally, we report the serendipitous detection of SLE-1, which has no continuum counterparts in our 1.2 mm-band or multi-wavelength images, including ultra deep HST/WFC3 and Spitzer data. The SLE has a significant line at 249.9 GHz with a signal-to-noise ratio of 7.1. If the SLE is not a spurious source made by the unknown systematic noise of ALMA, the strong upper limits of our multi-wavelength data suggest that the SLE would be a faint galaxy at z ≳ 6.

  3. Submillimeter ALMA Observations of the Dense Gas in the Low-Luminosity Type-1 Active Nucleus of NGC 1097

    NASA Astrophysics Data System (ADS)

    Izumi, Takuma; Kohno, Kotaro; Martín, Sergio; Espada, Daniel; Harada, Nanase; Matsushita, Satoki; Hsieh, Pei-Ying; Turner, Jean L.; Meier, David S.; Schinnerer, Eva; Imanishi, Masatoshi; Tamura, Yoichi; Curran, Max T.; Doi, Akihiro; Fathi, Kambiz; Krips, Melanie; Lundgren, Andreas A.; Nakai, Naomasa; Nakajima, Taku; Regan, Michael W.; Sheth, Kartik; Takano, Shuro; Taniguchi, Akio; Terashima, Yuichi; Tosaki, Tomoka; Wiklind, Tommy

    2013-10-01

    We present the first 100 pc scale view of the dense molecular gas in the central ˜ 1.3 kpc of the type-1 Seyfert NGC 1097, traced by HCN (J = 4-3) and HCO+ (J = 4-3) lines afforded with ALMA band 7. This galaxy shows significant HCN enhancement with respect to HCO+ and CO in the low-J transitions, which seems to be a common characteristic in AGN environments. Using the ALMA data, we consider the characteristics of the dense gas around this AGN, and search for the mechanism of HCN enhancement. We find a high HCN (J = 4-3) to HCO+ (J = 4-3) line ratio in the nucleus. The upper limit of the brightness temperature ratio of HCN (v2 ˜ 11f, J = 4-3) to HCN (J = 4-3) is 0.08, which indicates that IR pumping does not significantly affect the pure rotational population in this nucleus. We also find a higher HCN (J = 4-3) to CS (J = 7-6) line ratio in NGC 1097 than in starburst galaxies, which is more than 12.7 on the brightness temperature scale. Combined with similar observations from other galaxies, we tentatively suggest that this ratio appears to be higher in AGN-host galaxies than in pure starburst ones, similar to the widely used HCN to HCO+ ratio. LTE and non-LTE modeling of the observed HCN and HCO+ lines using J = 4-3 and 1-0 data from ALMA, and J = 3-2 data from SMA, reveals a high HCN to HCO+ abundance ratio (5 ≤ [HCN]/[HCO+] ≤ 20: non-LTE analysis) in the nucleus, and that the high-J lines (J = 4-3 and 3-2) are emitted from dense (104.5 cm-3 ≤ nH2 ≤ 106 cm-3), hot (70 K ≤ Tkin ≤ 550 K) regions. Finally we propose that ``high-temperature chemistry'' is more plausible to explain the observed enhanced HCN emission in NGC 1097 than pure gas-phase PDR/XDR chemistry.

  4. STAR FORMATION AND GAS KINEMATICS OF QUASAR HOST GALAXIES AT z {approx} 6: NEW INSIGHTS FROM ALMA

    SciTech Connect

    Wang Ran; Carilli, Chris L.; Wagg, Jeff; Walter, Fabian; Lentati, Lindley; Fan, Xiaohui; Narayanan, Desika; Riechers, Dominik A.; Bertoldi, Frank; Strauss, Michael A.; Cox, Pierre; Neri, Roberto; Omont, Alain; Menten, Karl M.; Knudsen, Kirsten K.; Jiang Linhua

    2013-08-10

    We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the [C II] 158 {mu}m fine structure line and dust continuum emission from the host galaxies of five redshift 6 quasars. We also report complementary observations of 250 GHz dust continuum and CO (6-5) line emission from the z = 6.00 quasar SDSS J231038.88+185519.7 using the IRAM facilities. The ALMA observations were carried out in the extended array at 0.''7 resolution. We have detected the line and dust continuum in all five objects. The derived [C II] line luminosities are 1.6 Multiplication-Sign 10{sup 9} to 8.7 Multiplication-Sign 10{sup 9} L{sub Sun} and the [C II]-to-FIR luminosity ratios are 2.9-5.1 Multiplication-Sign 10{sup -4}, which is comparable to the values found in other high-redshift quasar-starburst systems and local ultra-luminous infrared galaxies. The sources are marginally resolved and the intrinsic source sizes (major axis FWHM) are constrained to be 0.''3-0.''6 (i.e., 1.7-3.5 kpc) for the [C II] line emission and 0.''2-0.''4 (i.e., 1.2-2.3 kpc) for the continuum. These measurements indicate that there is vigorous star formation over the central few kpc in the quasar host galaxies. The ALMA observations also constrain the dynamical properties of the star-forming gas in the nuclear region. The intensity-weighted velocity maps of three sources show clear velocity gradients. Such velocity gradients are consistent with a rotating, gravitationally bound gas component, although they are not uniquely interpreted as such. Under the simplifying assumption of rotation, the implied dynamical masses within the [C II]-emitting regions are of order 10{sup 10}-10{sup 11} M{sub Sun }. Given these estimates, the mass ratios between the supermassive black holes and the spheroidal bulge are an order of magnitude higher than the mean value found in local spheroidal galaxies, which is in agreement with results from previous CO observations of high redshift quasars.

  5. The fast molecular outflow in the Seyfert galaxy IC 5063 as seen by ALMA

    NASA Astrophysics Data System (ADS)

    Morganti, Raffaella; Oosterloo, Tom; Oonk, J. B. Raymond; Frieswijk, Wilfred; Tadhunter, Clive

    2015-08-01

    We use high-resolution (0.5 arcsec) CO(2-1) observations performed with the Atacama Large Millimetre/submillimetre Array to trace the kinematics of the molecular gas in the Seyfert 2 galaxy IC 5063. The data reveal that the kinematics of the gas is very complex. A fast outflow of molecular gas extends along the entire radio jet (~1 kpc), with the highest outflow velocities about 0.5 kpc from the nucleus, at the location of the brighter hot spot in the western lobe. The ALMA data show that a massive, fast outflow with velocities up to 650kms-1 of cold molecular gas is present, in addition to the outflow detected earlier in warm H2, H i and ionized gas. All phases of the gas outflow show similar kinematics. IC 5063 appears to be one of the best examples of the multi-phase nature of AGN-driven outflows. Both the central AGN and the radio jet could energetically drive the outflow, however, the characteristics of the outflowing gas point to the radio jet being the main driver. This is an important result because IC 5063, although one of the most powerful Seyfert galaxies, is a relatively weak radio source (P1.4 GHz = 3 × 1023 W Hz-1). All the observed characteristics can be described by a scenario of a radio plasma jet expanding into a clumpy medium, interacting directly with the clouds and inflating a cocoon that drives a lateral outflow into the interstellar medium. This model is consistent with results obtained by recent simulations. A stronger, direct interaction between the jet and a gas cloud is present at the location of the brighter western lobe. This interaction may also be responsible for the asymmetry in the radio brightness of the two lobes. Even assuming the most conservative values for the conversion factor CO-to-H2, we find that the mass of the outflowing gas is between 1.9 and 4.8 × 107 M⊙, of which between 0.5 and 1.3 × 107 M⊙ is associated with the fast outflow at the location of the western lobe. These amounts are much larger than those of the

  6. Molecular line emission in NGC 1068 imaged with ALMA. I. An AGN-driven outflow in the dense molecular gas

    NASA Astrophysics Data System (ADS)

    García-Burillo, S.; Combes, F.; Usero, A.; Aalto, S.; Krips, M.; Viti, S.; Alonso-Herrero, A.; Hunt, L. K.; Schinnerer, E.; Baker, A. J.; Boone, F.; Casasola, V.; Colina, L.; Costagliola, F.; Eckart, A.; Fuente, A.; Henkel, C.; Labiano, A.; Martín, S.; Márquez, I.; Muller, S.; Planesas, P.; Ramos Almeida, C.; Spaans, M.; Tacconi, L. J.; van der Werf, P. P.

    2014-07-01

    Aims: We investigate the fueling and the feedback of star formation and nuclear activity in NGC 1068, a nearby (D = 14 Mpc) Seyfert 2 barred galaxy, by analyzing the distribution and kinematics of the molecular gas in the disk. We aim to understand if and how gas accretion can self-regulate. Methods: We have used the Atacama Large Millimeter Array (ALMA) to map the emission of a set of dense molecular gas (n(H2) ≃ 105 - 6 cm-3) tracers (CO(3-2), CO(6-5), HCN(4-3), HCO+(4-3), and CS(7-6)) and their underlying continuum emission in the central r ~ 2 kpc of NGC 1068 with spatial resolutions ~0.3″ - 0.5″ (~20-35 pc for the assumed distance of D = 14 Mpc). Results: The sensitivity and spatial resolution of ALMA give an unprecedented detailed view of the distribution and kinematics of the dense molecular gas (n(H2) ≥ 105 - 6cm-3) in NGC 1068. Molecular line and dust continuum emissions are detected from a r ~ 200 pc off-centered circumnuclear disk (CND), from the 2.6 kpc-diameter bar region, and from the r ~ 1.3 kpc starburst (SB) ring. Most of the emission in HCO+, HCN, and CS stems from the CND. Molecular line ratios show dramatic order-of-magnitude changes inside the CND that are correlated with the UV/X-ray illumination by the active galactic nucleus (AGN), betraying ongoing feedback. We used the dust continuum fluxes measured by ALMA together with NIR/MIR data to constrain the properties of the putative torus using CLUMPY models and found a torus radius of 20+6-10pc. The Fourier decomposition of the gas velocity field indicates that rotation is perturbed by an inward radial flow in the SB ring and the bar region. However, the gas kinematics from r ~ 50 pc out to r ~ 400 pc reveal a massive (Mmol~ 2.7+0.9-1.2 × 107 M⊙) outflow in all molecular tracers. The tight correlation between the ionized gas outflow, the radio jet, and the occurrence of outward motions in the disk suggests that the outflow is AGN driven. Conclusions: The molecular outflow is likely

  7. VizieR Online Data Catalog: ALMA and GeMS observations of the OMC1 region (Eisner+, 2016)

    NASA Astrophysics Data System (ADS)

    Eisner, J. A.; Bally, J. M.; Ginsburg, A.; Sheehan, P. D.

    2016-09-01

    We mapped a region around the OMC1 BN/KL outflow in the ONC with ALMA. The map is comprised of 108 mosaicked pointings in the northwest region of the OMC1 outflow and 39 pointings in the southeast region. The fields were observed at 230GHz frequency (Band 6), corresponding to a wavelength of 1.3mm. Observations were taken between 2014 July 19 and 2015 April 05. The angular resolution of the observations was approximately 1". We observed the OMC1 region in Orion with GeMS at the Gemini South telescope between 2012 December 30 and 2013 February 28 (see Bally et al. 2015, J/A+A/579/A130). We observed in the Ks filter, as well as the narrow Fe[II] and H2 filters, producing images with angular resolutions of ~0.06". (3 data files).

  8. Interferometric Mapping of Magnetic Fields: The ALMA View of the Massive Star-forming Clump W43-MM1

    NASA Astrophysics Data System (ADS)

    Cortes, Paulo C.; Girart, Josep M.; Hull, Charles L. H.; Sridharan, Tirupati K.; Louvet, Fabien; Plambeck, Richard; Li, Zhi-Yun; Crutcher, Richard M.; Lai, Shih-Ping

    2016-07-01

    Here, we present the first results from ALMA observations of 1 mm polarized dust emission toward the W43-MM1 high-mass star-forming clump. We have detected a highly fragmented filament with source masses ranging from 14 M {}⊙ to 312 M {}⊙ , where the largest fragment, source A, is believed to be one of the most massive in our Galaxy. We found a smooth, ordered, and detailed polarization pattern throughout the filament, which we used to derived magnetic field morphologies and strengths for 12 out of the 15 fragments detected ranging from 0.2 to 9 mG. The dynamical equilibrium of each fragment was evaluated finding that all the fragments are in a super-critical state that is consistent with previously detected infalling motions toward W43-MM1. Moreover, there are indications suggesting that the field is being dragged by gravity as the whole filament is collapsing.

  9. A candidate circumbinary Keplerian disk in G35.20-0.74 N: A study with ALMA

    NASA Astrophysics Data System (ADS)

    Sánchez-Monge, Á.; Cesaroni, R.; Beltrán, M. T.; Kumar, M. S. N.; Stanke, T.; Zinnecker, H.; Etoka, S.; Galli, D.; Hummel, C. A.; Moscadelli, L.; Preibisch, T.; Ratzka, T.; van der Tak, F. F. S.; Vig, S.; Walmsley, C. M.; Wang, K.-S.

    2013-04-01

    We report on ALMA observations of continuum and molecular line emission with 0."4 resolution towards the high-mass star-forming region G35.20-0.74 N. Two dense cores are detected in typical hot-core tracers (e.g., CH3CN) that reveal velocity gradients. In one of these cores, the velocity field can be fitted with an almost edge-on Keplerian disk rotating about a central mass of ~18 M⊙. This finding is consistent with the results of a recent study of the CO first overtone bandhead emission at 2.3 μm towards G35.20-0.74 N. The disk radius and mass are ≳2500 au and ~3 M⊙. To reconcile the observed bolometric luminosity (~3 × 104 L⊙) with the estimated stellar mass of 18 M⊙, we propose that the latter is the total mass of a binary system.

  10. revealing H{sub 2}D{sup +} depletion and compact structure in starless and protostellar cores with ALMA

    SciTech Connect

    Friesen, R. K.; Di Francesco, J.; Bourke, T. L.; Caselli, P.; Jørgensen, J. K.; Pineda, J. E.; Wong, M.

    2014-12-10

    We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the submillimeter dust continuum and H{sub 2}D{sup +} 1{sub 10}-1{sub 11} emission toward two evolved, potentially protostellar cores within the Ophiuchus molecular cloud, Oph A SM1 and SM1N. The data reveal small-scale condensations within both cores, with mass upper limits of M ≲ 0.02 M {sub ☉} (∼20 M {sub Jup}). The SM1 condensation is consistent with a nearly symmetric Gaussian source with a width of only 37 AU. The SM1N condensation is elongated and extends 500 AU along its major axis. No evidence for substructure is seen in either source. A Jeans analysis indicates that these sources are unlikely to fragment, suggesting that both will form single stars. H{sub 2}D{sup +} is only detected toward SM1N, offset from the continuum peak by ∼150-200 AU. This offset may be due to either heating from an undetected, young, low-luminosity protostellar source or first hydrostatic core, or HD (and consequently H{sub 2}D{sup +}) depletion in the cold center of the condensation. We propose that SM1 is protostellar and that the condensation detected by ALMA is a warm (T ∼ 30-50 K) accretion disk. The less concentrated emission of the SM1N condensation suggests that it is still starless, but we cannot rule out the presence of a low-luminosity source, perhaps surrounded by a pseudodisk. These data observationally reveal the earliest stages of the formation of circumstellar accretion regions and agree with theoretical predictions that disk formation can occur very early in the star formation process, coeval with or just after the formation of a first hydrostatic core or protostar.

  11. ALMA and VLA measurements of frequency-dependent time lags in Sagittarius A*: evidence for a relativistic outflow

    NASA Astrophysics Data System (ADS)

    Brinkerink, Christiaan D.; Falcke, Heino; Law, Casey J.; Barkats, Denis; Bower, Geoffrey C.; Brunthaler, Andreas; Gammie, Charles; Impellizzeri, C. M. Violette; Markoff, Sera; Menten, Karl M.; Moscibrodzka, Monika; Peck, Alison; Rushton, Anthony P.; Schaaf, Reinhold; Wright, Melvyn

    2015-04-01

    Context. Radio and mm-wavelength observations of Sagittarius A* (Sgr A*), the radio source associated with the supermassive black hole at the center of our Galaxy, show that it behaves as a partially self-absorbed synchrotron-emitting source. The measured size of Sgr A* shows that the mm-wavelength emission comes from a small region and consists of the inner accretion flow and a possible collimated outflow. Existing observations of Sgr A* have revealed a time lag between light curves at 43 GHz and 22 GHz, which is consistent with a rapidly expanding plasma flow and supports the presence of a collimated outflow from the environment of an accreting black hole. Aims: Here we wish to measure simultaneous frequency-dependent time lags in the light curves of Sgr A* across a broad frequency range to constrain direction and speed of the radio-emitting plasma in the vicinity of the black hole. Methods: Light curves of Sgr A* were taken in May 2012 using ALMA at 100 GHz using the VLA at 48, 39, 37, 27, 25.5, and 19 GHz. As a result of elevation limits and the longitude difference between the stations, the usable overlap in the light curves is approximately four hours. Although Sgr A* was in a relatively quiet phase, the high sensitivity of ALMA and the VLA allowed us to detect and fit maxima of an observed minor flare where flux density varied by ~10%. Results: The fitted times of flux density maxima at frequencies from 100 GHz to 19 GHz, as well as a cross-correlation analysis, reveal a simple frequency-dependent time lag relation where maxima at higher frequencies lead those at lower frequencies. Taking the observed size-frequency relation of Sgr A* into account, these time lags suggest a moderately relativistic (lower estimates: 0.5c for two-sided, 0.77c for one-sided) collimated outflow.

  12. Planck's Dusty GEMS. II. Extended [CII] emission and absorption in the Garnet at z = 3.4 seen with ALMA

    NASA Astrophysics Data System (ADS)

    Nesvadba, N.; Kneissl, R.; Cañameras, R.; Boone, F.; Falgarone, E.; Frye, B.; Gerin, M.; Koenig, S.; Lagache, G.; Le Floc'h, E.; Malhotra, S.; Scott, D.

    2016-08-01

    We present spatially resolved ALMA [CII] observations of the bright (flux density S350 = 400 mJy at 350 μm), gravitationally lensed, starburst galaxy PLCK G045.1+61.1 at z = 3.427, the "Garnet". This source is part of our set of "Planck's Dusty GEMS", discovered with the Planck's all-sky survey. Two emission-line clouds with a relative velocity offset of ~600 km s-1 extend towards north-east and south-west, respectively, of a small, intensely star-forming clump with a star-formation intensity of 220 M⊙ yr-1 kpc-2, akin to maximal starbursts. [CII] is also seen in absorption, with a redshift of +350 km s-1 relative to the brightest CO component. [CII] absorption has previously only been found in the Milky Way along sightlines toward bright high-mass star-forming regions, and this is the first detection in another galaxy. Similar to Galactic environments, the [CII] absorption feature is associated with [CI] emission, implying that this is diffuse gas shielded from the UV radiation of the clump, and likely at large distances from the clump. Since absorption can only be seen in front of a continuum source, the gas in this structure can definitely be attributed to gas flowing towards the clump. The absorber could be part of a cosmic filament or merger debris being accreted onto the galaxy. We discuss our results also in light of the on-going debate of the origin of the [CII] deficit in dusty star-forming galaxies. Based on data obtained with ALMA in program 2013.1.01230.S, and with EMIR on the IRAM 30 m telescope in program 223-13.

  13. Towards detecting methanol emission in low-mass protoplanetary discs with ALMA: the role of non-LTE excitation

    NASA Astrophysics Data System (ADS)

    Parfenov, S. Yu.; Semenov, D. A.; Sobolev, A. M.; Gray, M. D.

    2016-08-01

    The understanding of organic content of protoplanetary discs is one of the main goals of the planet formation studies. As an attempt to guide the observational searches for weak lines of complex species in discs, we modelled the (sub)millimetre spectrum of gaseous methanol (CH3OH), one of the simplest organic molecules, in the representative T Tauri system. We used 1+1D disc physical model coupled to the gas-grain ALCHEMIC chemical model with and without 2D-turbulent mixing. The computed CH3OH abundances along with the CH3OH scheme of energy levels of ground and excited torsional states were used to produce model spectra obtained with the non-local thermodynamic equilibrium (non-LTE) 3D line radiative transfer code LIME. We found that the modelled non-LTE intensities of the CH3OH lines can be lower by factor of >10-100 than those calculated under assumption of LTE. Though population inversion occurs in the model calculations for many (sub)millimetre transitions, it does not lead to the strong maser amplification and noticeably high line intensities. We identify the strongest CH3OH (sub)millimetre lines that could be searched for with the Atacama Large Millimeter Array (ALMA) in nearby discs. The two best candidates are the CH3OH 50 - 40A+ (241.791 GHz) and 5-1 - 4-1E (241.767 GHz) lines, which could possibly be detected with the ˜5σ signal-to-noise ratio after ˜3 h of integration with the full ALMA array.

  14. AN ALMA SURVEY OF SUBMILLIMETER GALAXIES IN THE EXTENDED CHANDRA DEEP FIELD SOUTH: SOURCE CATALOG AND MULTIPLICITY

    SciTech Connect

    Hodge, J. A.; Walter, F.; Decarli, R.; Karim, A.; Smail, I.; Swinbank, A. M.; Alexander, D. M.; Danielson, A. L. R.; Edge, A. C.; Biggs, A. D.; De Breuck, C.; Ivison, R. J.; Weiss, A.; Bertoldi, F.; Brandt, W. N.; Chapman, S. C.; Coppin, K. E. K.; Cox, P.; Dannerbauer, H.; Greve, T. R.; and others

    2013-05-01

    We present an Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 0 survey of 126 submillimeter sources from the LABOCA ECDFS Submillimeter Survey (LESS). Our 870 {mu}m survey with ALMA (ALESS) has produced maps {approx}3 Multiplication-Sign deeper and with a beam area {approx}200 Multiplication-Sign smaller than the original LESS observations, doubling the current number of interferometrically-observed submillimeter sources. The high resolution of these maps allows us to resolve sources that were previously blended and accurately identify the origin of the submillimeter emission. We discuss the creation of the ALESS submillimeter galaxy (SMG) catalog, including the main sample of 99 SMGs and a supplementary sample of 32 SMGs. We find that at least 35% (possibly up to 50%) of the detected LABOCA sources have been resolved into multiple SMGs, and that the average number of SMGs per LESS source increases with LESS flux density. Using the (now precisely known) SMG positions, we empirically test the theoretical expectation for the uncertainty in the single-dish source positions. We also compare our catalog to the previously predicted radio/mid-infrared counterparts, finding that 45% of the ALESS SMGs were missed by this method. Our {approx}1.''6 resolution allows us to measure a size of {approx}9 kpc Multiplication-Sign 5 kpc for the rest-frame {approx}300 {mu}m emission region in one resolved SMG, implying a star formation rate surface density of 80 M{sub Sun} yr{sup -1} kpc{sup -2}, and we constrain the emission regions in the remaining SMGs to be <10 kpc. As the first statistically reliable survey of SMGs, this will provide the basis for an unbiased multiwavelength study of SMG properties.

  15. Molecular line emission in NGC 1068 imaged with ALMA. II. The chemistry of the dense molecular gas

    NASA Astrophysics Data System (ADS)

    Viti, S.; García-Burillo, S.; Fuente, A.; Hunt, L. K.; Usero, A.; Henkel, C.; Eckart, A.; Martin, S.; Spaans, M.; Muller, S.; Combes, F.; Krips, M.; Schinnerer, E.; Casasola, V.; Costagliola, F.; Marquez, I.; Planesas, P.; van der Werf, P. P.; Aalto, S.; Baker, A. J.; Boone, F.; Tacconi, L. J.

    2014-10-01

    Aims: We present a detailed analysis of Atacama Large Millimeter/submillimeter Array (ALMA) Bands 7 and 9 data of CO, HCO+, HCN, and CS, augmented with Plateau de Bure Interferometer (PdBI) data of the ~200 pc circumnuclear disc (CND) and the ~1.3 kpc starburst ring (SB ring) of NGC 1068, a nearby (D = 14 Mpc) Seyfert 2 barred galaxy. We aim to determine the physical characteristics of the dense gas present in the CND, and to establish whether the different line intensity ratios we find within the CND, as well as between the CND and the SB ring, are due to excitation effects (gas density and temperature differences) or to a different chemistry. Methods: We estimate the column densities of each species in local thermodynamic equilibrium (LTE). We then compute large one-dimensional, non-LTE radiative transfer grids (using RADEX) by using only the CO transitions first, and then all the available molecules to constrain the densities, temperatures, and column densities within the CND. We finally present a preliminary set of chemical models to determine the origin of the gas. Results: We find that, in general, the gas in the CND is very dense (>105 cm-3) and hot (T> 150 K), with differences especially in the temperature across the CND. The AGN position has the lowest CO/HCO+, CO/HCN, and CO/CS column density ratios. The RADEX analyses seem to indicate that there is chemical differentiation across the CND. We also find differences between the chemistry of the SB ring and some regions of the CND; the SB ring is also much colder and less dense than the CND. Chemical modelling does not succeed in reproducing all the molecular ratios with one model per region, suggesting the presence of multi-gas phase components. Conclusions: The LTE, RADEX, and chemical analyses all indicate that more than one gas-phase component is necessary to uniquely fit all the available molecular ratios within the CND. A higher number of molecular transitions at the ALMA resolution is necessary to

  16. Distributions of molecules in the circumnuclear disk and surrounding starburst ring in the Seyfert galaxy NGC 1068 observed with ALMA

    NASA Astrophysics Data System (ADS)

    Takano, Shuro; Nakajima, Taku; Kohno, Kotaro; Harada, Nanase; Herbst, Eric; Tamura, Yoichi; Izumi, Takuma; Taniguchi, Akio; Tosaki, Tomoka

    2014-07-01

    Sensitive observations with the Atacama Large Millimeter/submillimeter Array (ALMA) allow astronomers to observe the detailed distributions of molecules with relatively weak intensity in nearby galaxies. In particular, we report distributions of several molecular transitions including shock and dust related species (13CO J = 1-0, C18O J = 1-0, 13CN N = 1-0, CS J = 2-1, SO JN = 32-21, HNCO JKa,Kc = 50,5-40,4, HC3N J = 11-10, 12-11, CH3OH JK = 2K-1K, and CH3CN JK = 6K-5K) in the nearby Seyfert 2 galaxy NGC 1068 observed with the ALMA early science program. The central ˜ 1'(˜ 4.3 kpc) of this galaxy was observed in the 100-GHz region covering ˜ 96-100 GHz and ˜ 108-111 GHz with an angular resolution of ˜ 4'' × 2'' (290 pc × 140 pc) to study the effects of an active galactic nucleus and its surrounding starburst ring on molecular abundances. Here, we present images and report a classification of molecular distributions into three main categories: (1) molecules concentrated in the circumnuclear disk (CND) (SO JN = 32-21, HC3N J = 11-10, 12-11, and CH3CN JK = 6K-5K), (2) molecules distributed both in the CND and the starburst ring (CS J = 2-1 and CH3OH JK = 2K-1K), and (3) molecules distributed mainly in the starburst ring (13CO J = 1-0 and C18O J = 1-0). Since most of the molecules such as HC3N observed in the CND are easily dissociated by UV photons and X-rays, our results indicate that these molecules must be effectively shielded. In the starburst ring, the relative intensity of methanol at each clumpy region is not consistent with those of 13CO, C18O, or CS. This difference is probably caused by the unique formation and destruction mechanisms of CH3OH.

  17. ALMA Observations of the Submillimeter Dense Molecular Gas Tracers in the Luminous Type-1 Active Nucleus of NGC 7469

    NASA Astrophysics Data System (ADS)

    Izumi, Takuma; Kohno, Kotaro; Aalto, Susanne; Doi, Akihiro; Espada, Daniel; Fathi, Kambiz; Harada, Nanase; Hatsukade, Bunyo; Hattori, Takashi; Hsieh, Pei-Ying; Ikarashi, Soh; Imanishi, Masatoshi; Iono, Daisuke; Ishizuki, Sumio; Krips, Melanie; Martín, Sergio; Matsushita, Satoki; Meier, David S.; Nagai, Hiroshi; Nakai, Naomasa; Nakajima, Taku; Nakanishi, Kouichiro; Nomura, Hideko; Regan, Michael W.; Schinnerer, Eva; Sheth, Kartik; Takano, Shuro; Tamura, Yoichi; Terashima, Yuichi; Tosaki, Tomoka; Turner, Jean L.; Umehata, Hideki; Wiklind, Tommy

    2015-09-01

    We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 1 observations of the central kiloparsec region of the luminous type 1 Seyfert galaxy NGC 7469 with unprecedented high resolution (0.″5 ×0.″4 = 165 × 132 pc) at submillimeter wavelengths. Utilizing the wide bandwidth of ALMA, we simultaneously obtained HCN(4-3), HCO+(4-3), CS(7-6), and partially CO(3-2) line maps, as well as the 860 μm continuum. The region consists of the central ˜1″ component and the surrounding starburst ring with a radius of ˜1.″5-2.″5. Several structures connect these components. Except for CO(3-2), these dense gas tracers are significantly concentrated toward the central ˜1″, suggesting their suitability to probe the nuclear regions of galaxies. Their spatial distribution resembles well those of centimeter and mid-infrared continuum emissions, but it is anticorrelated with the optical one, indicating the existence of dust-obscured star formation. The integrated intensity ratios of HCN(4-3)/HCO+(4-3) and HCN(4-3)/CS(7-6) are higher at the active galactic nucleus (AGN) position than at the starburst ring, which is consistent with our previous findings (submillimeter-HCN enhancement). However, the HCN(4-3)/HCO+(4-3) ratio at the AGN position of NGC 7469 (1.11 ± 0.06) is almost half of the corresponding value of the low-luminosity type 1 Seyfert galaxy NGC 1097 (2.0 ± 0.2), despite the more than two orders of magnitude higher X-ray luminosity of NGC 7469. But the ratio is comparable to that of the close vicinity of the AGN of NGC 1068 (˜1.5). Based on these results, we speculate that some heating mechanisms other than X-ray (e.g., mechanical heating due to an AGN jet) can contribute significantly for shaping the chemical composition in NGC 1097.

  18. ALMA Observations of the Molecular Gas in the Debris Disk of the 30 Myr Old Star HD 21997

    NASA Technical Reports Server (NTRS)

    Kospal, A.; Moor, A.; Juhasz, A.; Abraham, P.; Apai, D.; Csengeri, T.; Grady, C. A.; Henning, Th.; Hughes, A. M.; Kiss, Cs.; Pascucci, I.; Schmalzl, M.

    2013-01-01

    The 30 Myr old A3-type star HD 21997 is one of the two known debris dust disks having a measurable amount of cold molecular gas. With the goal of understanding the physical state, origin, and evolution of the gas in young debris disks, we obtained CO line observations with the Atacama Large Millimeter/submillimeter Array (ALMA). Here, we report on the detection of (12)CO and (13)CO in the J = 2-1 and J = 3-2 transitions and C(18)O in the J = 2-1 line. The gas exhibits a Keplerian velocity curve, one of the few direct measurements of Keplerian rotation in young debris disks. The measured CO brightness distribution could be reproduced by a simple star+disk system, whose parameters are r(sub in) < 26 AU, r(sub out) = 138 +/- 20 AU, Stellar M = 1.8 +0.5/-0.2 Solar M, and i = 32. Deg. 6 +/- 3 deg..1. The total CO mass, as calculated from the optically thin C(18)O line, is about (4-8) ×10(exp -2 ) Solar M, while the CO line ratios suggest a radiation temperature on the order of 6-9 K. Comparing our results with those obtained for the dust component of the HD 21997 disk from ALMA continuum observations by Moor et al., we conclude that comparable amounts of CO gas and dust are present in the disk. Interestingly, the gas and dust in the HD 21997 system are not colocated, indicating a dust-free inner gas disk within 55 AU of the star. We explore two possible scenarios for the origin of the gas. A secondary origin, which involves gas production from colliding or active planetesimals, would require unreasonably high gas production rates and would not explain why the gas and dust are not colocated. We propose that HD 21997 is a hybrid system where secondary debris dust and primordial gas coexist. HD 21997, whose age exceeds both the model predictions for disk clearing and the ages of the oldest T Tauri-like or transitional gas disks in the literature, may be a key object linking the primordial and the debris phases of disk evolution.

  19. ALMA OBSERVATIONS OF THE MOLECULAR GAS IN THE DEBRIS DISK OF THE 30 Myr OLD STAR HD 21997

    SciTech Connect

    Kóspál, Á.; Moór, A.; Ábrahám, P.; Kiss, Cs.; Juhász, A.; Schmalzl, M.; Apai, D.; Csengeri, T.; Grady, C. A.; Henning, Th.; Hughes, A. M.; Pascucci, I.

    2013-10-20

    The 30 Myr old A3-type star HD 21997 is one of the two known debris dust disks having a measurable amount of cold molecular gas. With the goal of understanding the physical state, origin, and evolution of the gas in young debris disks, we obtained CO line observations with the Atacama Large Millimeter/submillimeter Array (ALMA). Here, we report on the detection of {sup 12}CO and {sup 13}CO in the J = 2-1 and J = 3-2 transitions and C{sup 18}O in the J = 2-1 line. The gas exhibits a Keplerian velocity curve, one of the few direct measurements of Keplerian rotation in young debris disks. The measured CO brightness distribution could be reproduced by a simple star+disk system, whose parameters are r{sub in} < 26 AU, r{sub out} = 138 ± 20 AU, M{sub *}=1.8{sup +0.5}{sub -0.2} M{sub ☉}, and i = 32.°6 ± 3.°1. The total CO mass, as calculated from the optically thin C{sup 18}O line, is about (4-8) × 10{sup –2} M{sub ⊕}, while the CO line ratios suggest a radiation temperature on the order of 6-9 K. Comparing our results with those obtained for the dust component of the HD 21997 disk from ALMA continuum observations by Moór et al., we conclude that comparable amounts of CO gas and dust are present in the disk. Interestingly, the gas and dust in the HD 21997 system are not colocated, indicating a dust-free inner gas disk within 55 AU of the star. We explore two possible scenarios for the origin of the gas. A secondary origin, which involves gas production from colliding or active planetesimals, would require unreasonably high gas production rates and would not explain why the gas and dust are not colocated. We propose that HD 21997 is a hybrid system where secondary debris dust and primordial gas coexist. HD 21997, whose age exceeds both the model predictions for disk clearing and the ages of the oldest T Tauri-like or transitional gas disks in the literature, may be a key object linking the primordial and the debris phases of disk evolution.

  20. ALMA observations of infalling flows toward the Keplerian disk around the class I protostar L1489 IRS

    SciTech Connect

    Yen, Hsi-Wei; Takakuwa, Shigehisa; Ohashi, Nagayoshi; Aikawa, Yuri; Aso, Yusuke; Koyamatsu, Shin; Machida, Masahiro N.; Saigo, Kazuya; Saito, Masao; Tomida, Kengo; Tomisaka, Kohji

    2014-09-20

    We have conducted ALMA observations in the 1.3 mm continuum and {sup 12}CO (2-1), C{sup 18}O (2-1), and SO (5{sub 6}-4{sub 5}) lines toward L1489 IRS, a Class I protostar surrounded by a Keplerian disk and an infalling envelope. The Keplerian disk is clearly identified in the {sup 12}CO and C{sup 18}O emission, and its outer radius (∼700 AU) and mass (∼0.005 M {sub ☉}) are comparable to those of disks around T Tauri stars. The protostellar mass is estimated to be 1.6 M {sub ☉} with the inclination angle of 66°. In addition to the Keplerian disk, there are blueshifted and redshifted off-axis protrusions seen in the C{sup 18}O emission pointing toward the north and the south, respectively, adjunct to the middle part of the Keplerian disk. The shape and kinematics of these protrusions can be interpreted as streams of infalling flows with a conserved angular momentum following parabolic trajectories toward the Keplerian disk, and the mass infalling rate is estimated to be ∼5 × 10{sup –7} M {sub ☉} yr{sup –1}. The specific angular momentum of the infalling flows (∼2.5 × 10{sup –3} km s{sup –1} pc) is comparable to that at the outer radius of the Keplerian disk (∼4.8 × 10{sup –3} km s{sup –1} pc). The SO emission is elongated along the disk major axis and exhibits a linear velocity gradient along the axis, which is interpreted to mean that the SO emission primarily traces a ring region in the flared Keplerian disk at radii of ∼250-390 AU. The local enhancement of the SO abundance in the ring region can be due to the accretion shocks at the centrifugal radius where the infalling flows fall onto the disk. Our ALMA observations unveiled both the Keplerian disk and the infalling gas onto the disk, and the disk can further grow by accreting material and angular momenta from the infalling gas.

  1. ALMA Observations of the Molecular Gas in the Debris Disk of the 30 Myr Old Star HD 21997

    NASA Astrophysics Data System (ADS)

    Kóspál, Á.; Moór, A.; Juhász, A.; Ábrahám, P.; Apai, D.; Csengeri, T.; Grady, C. A.; Henning, Th.; Hughes, A. M.; Kiss, Cs.; Pascucci, I.; Schmalzl, M.

    2013-10-01

    The 30 Myr old A3-type star HD 21997 is one of the two known debris dust disks having a measurable amount of cold molecular gas. With the goal of understanding the physical state, origin, and evolution of the gas in young debris disks, we obtained CO line observations with the Atacama Large Millimeter/submillimeter Array (ALMA). Here, we report on the detection of 12CO and 13CO in the J = 2-1 and J = 3-2 transitions and C18O in the J = 2-1 line. The gas exhibits a Keplerian velocity curve, one of the few direct measurements of Keplerian rotation in young debris disks. The measured CO brightness distribution could be reproduced by a simple star+disk system, whose parameters are r in < 26 AU, r out = 138 ± 20 AU, M_*=1.8^{+0.5}_{-0.2} M ⊙, and i = 32.°6 ± 3.°1. The total CO mass, as calculated from the optically thin C18O line, is about (4-8) × 10-2 M ⊕, while the CO line ratios suggest a radiation temperature on the order of 6-9 K. Comparing our results with those obtained for the dust component of the HD 21997 disk from ALMA continuum observations by Moór et al., we conclude that comparable amounts of CO gas and dust are present in the disk. Interestingly, the gas and dust in the HD 21997 system are not colocated, indicating a dust-free inner gas disk within 55 AU of the star. We explore two possible scenarios for the origin of the gas. A secondary origin, which involves gas production from colliding or active planetesimals, would require unreasonably high gas production rates and would not explain why the gas and dust are not colocated. We propose that HD 21997 is a hybrid system where secondary debris dust and primordial gas coexist. HD 21997, whose age exceeds both the model predictions for disk clearing and the ages of the oldest T Tauri-like or transitional gas disks in the literature, may be a key object linking the primordial and the debris phases of disk evolution.

  2. Distribution of Molecules in the Circumnuclear Disk and Surrounding Starburst Ring in the Seyfert Galaxy NGC 1068 Observed with ALMA

    NASA Astrophysics Data System (ADS)

    Takano, S.; Nakajima, T.; Kohno, K.; Harada, N.; Herbst, E.; Tamura, Y.; Izumi, T.; Taniguchi, A.; Tosaki, T.

    2015-12-01

    We report distributions of several molecular transitions including shock and dust related species (13CO and C18O J = 1-0, 13CN N = 1-0, CS J = 2-1, SO JN = 32-21, HNCO JKa,Kc = 50,5-40,4, HC3N J = 11-10, 12-11, CH3OH JK = 2K-1K, and CH3CN JK = 6K-5K) in the nearby Seyfert 2 galaxy NGC 1068 observed with ALMA. The central ˜1' (˜4.3 kpc) of this galaxy was observed in the 100 GHz region with an angular resolution of ˜4" x 2" (290 pc x 140 pc) to study the effects of an active galactic nucleus and its surrounding starburst ring on molecular abundances. We report a classification of molecular distributions into three main categories. Organic molecules such as CH3CN are found to be concentrated in the circumnuclear disk. In the starburst ring, the intensity of methanol at each clumpy region is not consistent with that of 13CO.

  3. The ALMA-PILS survey: First detections of deuterated formamide and deuterated isocyanic acid in the interstellar medium

    NASA Astrophysics Data System (ADS)

    Coutens, A.; Jørgensen, J. K.; van der Wiel, M. H. D.; Müller, H. S. P.; Lykke, J. M.; Bjerkeli, P.; Bourke, T. L.; Calcutt, H.; Drozdovskaya, M. N.; Favre, C.; Fayolle, E. C.; Garrod, R. T.; Jacobsen, S. K.; Ligterink, N. F. W.; Öberg, K. I.; Persson, M. V.; van Dishoeck, E. F.; Wampfler, S. F.

    2016-05-01

    Formamide (NH2CHO) has previously been detected in several star-forming regions and is thought to be a precursor for different prebiotic molecules. Its formation mechanism is still debated, however. Observations of formamide, related species, and their isopotologues may provide useful clues to the chemical pathways leading to their formation. The Protostellar Interferometric Line Survey (PILS) represents an unbiased, high angular resolution and sensitivity spectral survey of the low-mass protostellar binary IRAS 16293-2422 with the Atacama Large Millimeter/submillimeter Array (ALMA). For the first time, we detect the three singly deuterated forms of NH2CHO (NH2CDO, cis- and trans-NHDCHO), as well as DNCO towards the component B of this binary source. The images reveal that the different isotopologues are all present in the same region. Based on observations of the 13C isotopologues of formamide and a standard 12C/13C ratio, the deuterium fractionation is found to be similar for the three different forms with a value of about 2%. The DNCO/HNCO ratio is also comparable to the D/H ratio of formamide (~1%). These results are in agreement with the hypothesis that NH2CHO and HNCO are chemically related through grain-surface formation.

  4. Spectroscopic FITS to the Alma Science Verification Band 6 Survey of the Orion Hot Core and Compact Ridge

    NASA Astrophysics Data System (ADS)

    Nagarajan, Satyakumar; McMillan, James P.; Burkhardt, Andrew M.; Neese, Christopher F.; De Lucia, Frank C.; Remijan, Anthony

    2016-06-01

    Individual spectral lines in astrophysical data are ordinarily assigned by comparison with line frequency and intensities predicted by catalogs. Here we seek to fit the spectra of specific sources within Orion KL that are first selected by ALMA's angular resolution and then by Doppler velocity class. For each molecule in this study, astrophysical reference lines are selected. Subsequent analyses of individual velocity components provide the astrophysical column density and temperature for these velocity regimes. These column densities and temperatures are then combined with results from the complete experimental spectra obtained from our laboratory spectra to model the molecule's contribution to the entire astrophysical spectrum [1]. Effects due to optical thickness and spectral overlap are included in the analyses. Examples for ethyl cyanide in the hot core and methanol in the compact ridge will be presented. [1] J. P. McMillan, S. M. Fortman, C. F. Neese, and F. C. De Lucia, "The Complete, Temperature Resolved Experi- mental Spectrum of Methanol (CH3OH) between 214.6 and 265.4 GHz," Astrophys. J., vol. 795, pp. 56(1-9), 2014.

  5. ALMA OBSERVATIONS OF {rho}-Oph 102: GRAIN GROWTH AND MOLECULAR GAS IN THE DISK AROUND A YOUNG BROWN DWARF

    SciTech Connect

    Ricci, L.; Testi, L.; Natta, A.; Scholz, A.; De Gregorio-Monsalvo, I.

    2012-12-20

    We present ALMA continuum and spectral line observations of the young brown dwarf {rho}-Oph 102 at about 0.89 mm and 3.2 mm. We detect dust emission from the disk at these wavelengths and derive an upper limit on the radius of the dusty disk of {approx}40 AU. The derived variation of the dust opacity with frequency in the millimeter (mm) provides evidence for the presence of mm-sized grains in the disk's outer regions. This result demonstrates that mm-sized grains are found even in the low-density environments of brown dwarf disks and challenges our current understanding of dust evolution in disks. The CO map at 345 GHz clearly reveals molecular gas emission at the location of the brown dwarf, indicating a gas-rich disk as typically found for disks surrounding young pre-main-sequence stars. We derive a disk mass of {approx}0.3%-1% of the mass of the central brown dwarf, similar to the typical values found for disks around more massive young stars.

  6. THE FIRST DETECTION OF THE 232 GHz VIBRATIONALLY EXCITED H{sub 2}O MASER IN ORION KL WITH ALMA

    SciTech Connect

    Hirota, Tomoya; Kim, Mi Kyoung; Honma, Mareki

    2012-09-20

    We investigated the ALMA science verification data of Orion KL and found a spectral signature of the vibrationally excited H{sub 2}O maser line at 232.68670 GHz ({nu}{sub 2} = 1, 5{sub 5,0}-6{sub 4,3}). This line has been detected previously in circumstellar envelopes of late-type stars but not in young stellar objects such as Orion KL. Thus, this is the first detection of the 232 GHz vibrationally excited H{sub 2}O maser in star-forming regions. The distribution of the 232 GHz maser is concentrated at the position of the radio Source I, which is remarkably different from other molecular lines. The spectrum shows a double-peak structure at the peak velocities of -2.1 and 13.3 km s{sup -1}. It appears to be consistent with the 22 GHz H{sub 2}O masers and 43 GHz SiO masers observed around Source I. Thus, the 232 GHz H{sub 2}O maser around Source I would be excited by the internal heating by an embedded protostar, being associated with either the root of the outflows/jets or the circumstellar disk around Source I, as traced by the 22 GHz H{sub 2}O masers or 43 GHz SiO masers, respectively.

  7. VLA and ALMA Imaging of the Massive Prestellar Core G11.92-0.61 MM2

    NASA Astrophysics Data System (ADS)

    Hunter, T. R.; Brogan, C. L.; Cyganowski, C. J.; Schnee, S.

    2016-05-01

    We have obtained new Jansky Very Large Array (VLA) observations at X, K, and Ka bands (3 cm, 1.3 cm, and 0.9 cm) which have resolved the continuum emission from the most promising candidate for a massive pre-stellar core discovered to date: G11.92-0.61 MM2. As described in Cyganowski et al. ([1]), this bright dust continuum source (190 mJy at 1.1 mm) exhibits no spectral line emission in sub-arcsecond-resolution Submillimeter Array (SMA) images across 24 GHz of bandwidth, including the typical tracers CO, HCN, HCO+, and N2H+. Astrochemical models require high density (> 109 cm-3) and low temperature (< 20 K) to explain the rare chemistry of this massive (M ≥ 30 M⊙) object, which may exist in a fleeting evolutionary state. This source is well detected and elongated in VLA Ka-band (9 mm) continuum image with a 0.25'' beam (800 AU), is marginally detected in poorer resolution (1) K-band (1.3 cm) data, and is undetected at X-band (3 cm) with 0.25'' resolution. In combination with existing SMA millimeter wavelength data, our results provide an accurate spectral energy distribution of this source, constraining the dust grain emissivity index to 1.0-1.6 and the luminosity to 3-37 L⊙. Preliminary results from ALMA Band 7 images confirm that the dust emission from MM2 is resolved in an east-west direction.

  8. ALMA Investigation of Vibrationally Excited HCN/HCO+/HNC Emission Lines in the AGN-Hosting Ultraluminous Infrared Galaxy IRAS 20551-4250

    NASA Astrophysics Data System (ADS)

    Imanishi, Masatoshi; Nakanishi, Kouichiro; Izumi, Takuma

    2016-07-01

    We present the results of ALMA Cycle 2 observations of the ultraluminous infrared galaxy IRAS 20551-4250 at HCN/HCO+/HNC J = 3-2 lines at both vibrational ground (v = 0) and vibrationally excited (v 2 = 1) levels. This galaxy contains a luminous buried active galactic nucleus (AGN), in addition to starburst activity, and our ALMA Cycle 0 data revealed a tentatively detected vibrationally excited HCN v 2 = 1f J = 4-3 emission line. In our ALMA Cycle 2 data, the HCN/HCO+/HNC J = 3-2 emission lines at v = 0 are clearly detected. The HCN and HNC v 2 = 1f J = 3-2 emission lines are also detected, but the HCO+ v 2 = 1f J = 3-2 emission line is not. Given the high energy level of v 2 = 1 and the resulting difficulty of collisional excitation, we compared these results with those of the calculation of infrared radiative pumping, using the available infrared 5-35 μm spectrum. We found that all of the observational results were reproduced if the HCN abundance was significantly higher than that of HCO+ and HNC. The flux ratio and excitation temperature between v 2 = 1f and v = 0, after correction for possible line opacity, suggests that infrared radiative pumping affects rotational (J-level) excitation at v = 0 at least for HCN and HNC. The HCN-to-HCO+ v = 0 flux ratio is higher than those of starburst-dominated regions, and will increase even more when the derived high HCN opacity is corrected. The enhanced HCN-to-HCO+ flux ratio in this AGN-hosting galaxy can be explained by the high HCN-to-HCO+ abundance ratio and sufficient HCN excitation at up to J = 4, rather than the significantly higher efficiency of infrared radiative pumping for HCN than HCO+.

  9. An intensely star-forming galaxy at z ∼ 7 with low dust and metal content revealed by deep ALMA and HST observations

    SciTech Connect

    Ouchi, Masami; Ono, Yoshiaki; Momose, Rieko; Ellis, Richard; Nakanishi, Kouichiro; Kohno, Kotaro; Tamura, Yoichi; Kurono, Yasutaka; Ashby, M. L. N.; Willner, S. P.; Fazio, G. G.; Shimasaku, Kazuhiro; Iono, Daisuke

    2013-12-01

    We report deep ALMA observations complemented by associated Hubble Space Telescope (HST) imaging for a luminous (m {sub UV} = 25) galaxy, 'Himiko', at a redshift of z = 6.595. The galaxy is remarkable for its high star formation rate, 100 M {sub ☉} yr{sup –1}, which has been securely estimated from our deep HST and Spitzer photometry, and the absence of any evidence for strong active galactic nucleus activity or gravitational lensing magnification. Our ALMA observations probe an order of magnitude deeper than previous IRAM observations, yet fail to detect a 1.2 mm dust continuum, indicating a flux of <52 μJy, which is comparable to or weaker than that of local dwarf irregulars with much lower star formation rates. We likewise provide a strong upper limit for the flux of [C II] 158 μm, L{sub [C} {sub II]}<5.4×10{sup 7} L{sub ⊙}, which is a diagnostic of the hot interstellar gas that is often described as a valuable probe for early galaxies. In fact, our observations indicate that Himiko lies off the local L{sub [C} {sub II]}-star formation rate scaling relation by a factor of more than 30. Both aspects of our ALMA observations suggest that Himiko is a unique object with a very low dust content and perhaps nearly primordial interstellar gas. Our HST images provide unique insight into the morphology of this remarkable source, highlighting an extremely blue core of activity and two less extreme associated clumps. Himiko is undergoing a triple major merger event whose extensive ionized nebula of Lyα emitting gas, discovered in our earlier work with Subaru, is powered by star formation and the dense circumgalactic gas. We are likely witnessing an early massive galaxy during a key period of its mass assembly close to the end of the reionization era.

  10. An alma survey of submillimeter galaxies in the extended Chandra deep field-south: The agn fraction and X-ray properties of submillimeter galaxies

    SciTech Connect

    Wang, S. X.; Brandt, W. N.; Luo, B.; Smail, I.; Alexander, D. M.; Danielson, A. L. R.; Karim, A.; Simpson, J. M.; Swinbank, A. M.; Hodge, J. A.; Walter, F.; Lehmer, B. D.; Wardlow, J. L.; Xue, Y. Q.; Chapman, S. C.; Coppin, K. E. K.; Dannerbauer, H.; De Breuck, C.; Menten, K. M.; Van der Werf, P. E-mail: niel@astro.psu.edu

    2013-12-01

    The large gas and dust reservoirs of submillimeter galaxies (SMGs) could potentially provide ample fuel to trigger an active galactic nucleus (AGN), but previous studies of the AGN fraction in SMGs have been controversial largely due to the inhomogeneity and limited angular resolution of the available submillimeter surveys. Here we set improved constraints on the AGN fraction and X-ray properties of the SMGs with Atacama Large Millimeter/submillimeter Array (ALMA) and Chandra observations in the Extended Chandra Deep Field-South (E-CDF-S). This study is the first among similar works to have unambiguously identified the X-ray counterparts of SMGs; this is accomplished using the fully submillimeter-identified, statistically reliable SMG catalog with 99 SMGs from the ALMA LABOCA E-CDF-S Submillimeter Survey. We found 10 X-ray sources associated with SMGs (median redshift z = 2.3), of which eight were identified as AGNs using several techniques that enable cross-checking. The other two X-ray detected SMGs have levels of X-ray emission that can be plausibly explained by their star formation activity. Six of the eight SMG-AGNs are moderately/highly absorbed, with N {sub H} > 10{sup 23} cm{sup –2}. An analysis of the AGN fraction, taking into account the spatial variation of X-ray sensitivity, yields an AGN fraction of 17{sub −6}{sup +16}% for AGNs with rest-frame 0.5-8 keV absorption-corrected luminosity ≥7.8 × 10{sup 42} erg s{sup –1}; we provide estimated AGN fractions as a function of X-ray flux and luminosity. ALMA's high angular resolution also enables direct X-ray stacking at the precise positions of SMGs for the first time, and we found four potential SMG-AGNs in our stacking sample.

  11. The Radial Distribution of H2 and CO in TW Hya as Revealed by Resolved ALMA Observations of CO Isotopologues

    NASA Astrophysics Data System (ADS)

    Schwarz, Kamber R.; Bergin, Edwin A.; Cleeves, L. Ilsedore; Blake, Geoffrey A.; Zhang, Ke; Öberg, Karin I.; van Dishoeck, Ewine F.; Qi, Chunhua

    2016-06-01

    CO is widely used as a tracer of molecular gas. However, there is now mounting evidence that gas phase carbon is depleted in the disk around TW Hya. Previous efforts to quantify this depletion have been hampered by uncertainties regarding the radial thermal structure in the disk. Here we present resolved ALMA observations of 13CO 3-2, C18O 3-2, 13CO 6-5, and C18O 6-5 emission in TW Hya, which allow us to derive radial gas temperature and gas surface density profiles, as well as map the CO abundance as a function of radius. These observations provide a measurement of the surface CO snowline at ˜30 AU and show evidence for an outer ring of CO emission centered at 53 AU, a feature previously seen only in less abundant species. Further, the derived CO gas temperature profile constrains the freeze out temperature of CO in the warm molecular layer to \\lt 21 K. Combined with the previous detection of HD 1-0, these data constrain the surface density of the warm H2 gas in the inner ˜30 AU such that {{{Σ }}}{warm{gas}}={4.7}-2.9+3.0 {{g}} {{cm}}-2{(R/10{au})}-1/2. We find that CO is depleted by two orders of magnitude from R=10{--}60 {{AU}}, with the small amount of CO returning to the gas phase inside the surface CO snowline insufficient to explain the overall depletion. Finally, this new data is used in conjunction with previous modeling of the TW Hya disk to constrain the midplane CO snowline to 17–23 AU.

  12. Properties of the Interstellar Medium in Star-Forming Galaxies at z ~ 1.4 Revealed with ALMA

    NASA Astrophysics Data System (ADS)

    Seko, Akifumi; Ohta, Kouji; Yabe, Kiyoto; Hatsukade, Bunyo; Akiyama, Masayuki; Iwamuro, Fumihide; Tamura, Naoyuki; Dalton, Gavin

    2016-03-01

    We conducted observations of 12CO(J = 5-4) and dust thermal continuum emission toward 20 star-forming galaxies on the main sequence at z ˜ 1.4 using ALMA to investigate the properties of the interstellar medium. The sample galaxies are chosen to trace the distributions of star-forming galaxies in diagrams of stellar mass versus star formation rate and stellar mass versus metallicity. We detected CO emission lines from 11 galaxies. The molecular gas mass is derived by adopting a metallicity-dependent CO-to-H2 conversion factor and assuming a CO(5-4)/CO(1-0) luminosity ratio of 0.23. Masses of molecular gas and its fractions (molecular gas mass/(molecular gas mass + stellar mass)) for the detected galaxies are in the ranges of (3.9-12) × 1010 M⊙ and 0.25-0.94, respectively; these values are significantly larger than those in local spiral galaxies. The molecular gas mass fraction decreases with increasing stellar mass; the relation holds for four times lower stellar mass than that covered in previous studies, and the molecular gas mass fraction decreases with increasing metallicity. Stacking analyses also show the same trends. Dust thermal emissions were clearly detected from two galaxies and marginally detected from five galaxies. Dust masses of the detected galaxies are (3.9-38) × 107 M⊙. We derived gas-to-dust ratios and found they are 3-4 times larger than those in local galaxies. The depletion times of molecular gas for the detected galaxies are (1.4-36) × 108 yr while the results of the stacking analysis show ˜3 × 108 yr. The depletion time tends to decrease with increasing stellar mass and metallicity though the trend is not so significant, which contrasts with the trends in local galaxies.

  13. Sub-kpc star formation law in the local luminous infrared galaxy IC 4687 as seen by ALMA

    NASA Astrophysics Data System (ADS)

    Pereira-Santaella, M.; Colina, L.; García-Burillo, S.; Planesas, P.; Usero, A.; Alonso-Herrero, A.; Arribas, S.; Cazzoli, S.; Emonts, B.; Piqueras López, J.; Villar-Martín, M.

    2016-03-01

    We analyze the spatially resolved (250 pc scales) and integrated star formation (SF) law in the local luminous infrared galaxy (LIRG) IC 4687. This is one of the first studies of the SF law on a starburst LIRG at these small spatial scales. We combined new interferometric ALMA CO(2-1) data with existing HST/NICMOS Paα narrowband imaging and VLT/SINFONI near-IR integral field spectroscopy to obtain accurate extinction-corrected SF rate (SFR) and cold molecular gas surface densities (Σgas and ΣSFR). We find that IC 4687 forms stars very efficiently with an average depletion time (tdep) of 160 Myr for the individual 250 pc regions. This is approximately one order of magnitude shorter than the tdep of local normal spirals and also shorter than that of main-sequence high-z objects, even when we use a Galactic αCO conversion factor. This result suggests a bimodal SF law in the ΣSFR∝ΣgasN representation. A universal SF law is recovered if we normalize the Σgas by the global dynamical time. However, at the spatial scales studied here, we find that the SF efficiency (or tdep) does not depend on the local dynamical time for this object. Therefore, an alternative normalization (e.g., free-fall time) should be found if a universal SF law exists at these scales. A FITS file for the reduced datacube is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/587/A44

  14. A multi-transition study of molecules toward NGC 1068 based on high-resolution imaging observations with ALMA

    NASA Astrophysics Data System (ADS)

    Nakajima, Taku; Takano, Shuro; Kohno, Kotaro; Harada, Nanase; Herbst, Eric; Tamura, Yoichi; Izumi, Takuma; Taniguchi, Akio; Tosaki, Tomoka

    2015-02-01

    We present 0.8-mm band molecular images and spectra obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) toward one of the nearest galaxies with an active galactic nucleus (AGN), NGC 1068. Distributions of CO isotopic species (13CO and C18O) J = 3-2, CN N = 3-2, and CS J = 7-6 are observed toward the circumnuclear disk (CND) and a part of the starburst ring with an angular resolution of ˜ 1.3" × 1.2". The physical properties of these molecules and shock-related molecules, such as HNCO, CH3CN, SO, and CH3OH, detected in the 3-mm band were estimated using rotation diagrams under the assumption of local thermodynamic equilibrium. The rotational temperatures of the CO isotopic species and the shock-related molecules in the CND are, respectively, 14-22 K and upper limits of 20-40 K. Although the column densities of the CO isotopic species in the CND are only from one-fifth to one-third of that in the starburst ring, those of the shock-related molecules are enhanced by a factor of 3-10 in the CND. We also discuss the chemistry of each species, and compare the fractional abundances in the CND and starburst ring with those of Galactic sources such as cold cores, hot cores, and shocked molecular clouds in order to study the overall characteristics. We find that the abundances of shock-related molecules are more similar to abundances in hot cores and/or shocked clouds than to cold cores. The CND hosts relatively complex molecules, which are often associated with shocked molecular clouds or hot cores. Because a high X-ray flux can dissociate these molecules, they must also reside in regions shielded from X-rays.

  15. The evolution of interstellar medium mass probed by dust emission: Alma observations at z = 0.3-2

    SciTech Connect

    Scoville, N.; Manohar, S.; Aussel, H.; Sheth, K.; Scott, K. S.; Sanders, D.; Ivison, R.; Pope, A.; Capak, P.; Vanden Bout, P.; Kartaltepe, J.; Robertson, B.; Lilly, S.

    2014-03-10

    The use of submillimeter dust continuum emission to probe the mass of interstellar dust and gas in galaxies is empirically calibrated using samples of local star-forming galaxies, Planck observations of the Milky Way, and high-redshift submillimeter galaxies. All of these objects suggest a similar calibration, strongly supporting the view that the Rayleigh-Jeans tail of the dust emission can be used as an accurate and very fast probe of the interstellar medium (ISM) in galaxies. We present ALMA Cycle 0 observations of the Band 7 (350 GHz) dust emission in 107 galaxies from z = 0.2 to 2.5. Three samples of galaxies with a total of 101 galaxies were stellar-mass-selected from COSMOS to have M {sub *} ≅ 10{sup 11} M {sub ☉}: 37 at z ∼ 0.4, 33 at z ∼ 0.9, and 31 at z = 2. A fourth sample with six infrared-luminous galaxies at z = 2 was observed for comparison with the purely mass-selected samples. From the fluxes detected in the stacked images for each sample, we find that the ISM content has decreased by a factor ∼6 from 1 to 2 × 10{sup 10} M {sub ☉} at both z = 2 and 0.9 down to ∼2 × 10{sup 9} M {sub ☉} at z = 0.4. The infrared-luminous sample at z = 2 shows a further ∼4 times increase in M {sub ISM} compared with the equivalent non-infrared-bright sample at the same redshift. The gas mass fractions are ∼2% ± 0.5%, 12% ± 3%, 14% ± 2%, and 53% ± 3% for the four subsamples (z = 0.4, 0.9, and 2 and infrared-bright galaxies).

  16. Properties of Interstellar Medium in Star-Forming Galaxies at z~1.4 revealed with ALMA

    NASA Astrophysics Data System (ADS)

    Seko, Akifumi; Ohta, Kouji; Hatsukade, Bunyo; Yabe, Kiyoto

    2015-08-01

    We made CO(J=5-4) observations of 20 star-forming galaxies at z~1.4 with ALMA to study properties of molecular gas with respect to the stellar mass and metallicity. Almost all of our sample galaxies are on the main sequnece of star-forming galaxies at this redshift. Uniqueness of the sample is gas phase metallicity is known for each galaxy. The metallicities of our sample galaxies are derived from near-infrared spectoscopic observations with Subaru/FMOS. The ranges of metallicity (12+log(O/H)) and stellar mass are 8.2-8.9 and 4×109 - 4×1011 Msun, respectively. The stellar mass range covers lower mass than that in previous studies. We detected CO emission lines from 11 galaxies. Molecular gas mass is derived by adopting metallicity-dependent CO-to-H2 conversion factor. The derived molecular gas masses of detected galaxies are (3-11)×1010 Msun. The molecular gas mass fractions are 0.25-0.94, and the fractions is lower in a more massive galaxy or a galaxy with higher metallicity. Stacking analysis also shows the same trends. However, it is difficult to conclude which of stellar mass and metallicity is a main cause for the relations. We try to constrain the inflow and outflow rate at z~1.4 by using an analytic chemical evolution model, in which gas in a galaxy is accumulated by inflow and consumed by star formation and outflow. The results is consistent with that from Hα luminosity assuming the Kennicutt-Schmidt law. Dust thermal continuum emissions are also observed, thus we would like to mention the evolution of gas-to-dust ratio in galaxies.

  17. ALMA Observations of the Transition from Infall Motion to Keplerian Rotation around the Late-phase Protostar TMC-1A

    NASA Astrophysics Data System (ADS)

    Aso, Yusuke; Ohashi, Nagayoshi; Saigo, Kazuya; Koyamatsu, Shin; Aikawa, Yuri; Hayashi, Masahiko; Machida, Masahiro N.; Saito, Masao; Takakuwa, Shigehisa; Tomida, Kengo; Tomisaka, Kohji; Yen, Hsi-Wei

    2015-10-01

    We have observed the Class I protostar TMC-1A with the Atacama Millimeter/submillimeter Array (ALMA) in the emissions of 12CO and C18O (J = 2–1) and 1.3 mm dust continuum. Continuum emission with a deconvolved size of 0.″50 × 0.″37, perpendicular to the 12CO outflow, is detected. It most likely traces a circumstellar disk around TMC-1A, as previously reported. In contrast, a more extended structure is detected in C18O, although it is still elongated with a deconvolved size of 3.″3 × 2.″2, indicating that C18O traces mainly a flattened envelope surrounding the disk and the central protostar. C18O shows a clear velocity gradient perpendicular to the outflow at higher velocities, indicative of rotation, while an additional velocity gradient along the outflow is found at lower velocities. The radial profile of the rotational velocity is analyzed in detail, finding that it is given as a power law ∝r‑a with an index of ∼0.5 at higher velocities. This indicates that the rotation at higher velocities can be explained as Keplerian rotation orbiting a protostar with a dynamical mass of 0.68 {M}ȯ (inclination corrected). The additional velocity gradient of C18O along the outflow is considered to be mainly infall motions in the envelope. Position–velocity diagrams made from models consisting of an infalling envelope and a Keplerian disk are compared with the observations, revealing that the observed infall velocity is ∼0.3 times smaller than the free-fall velocity yielded by the dynamical mass of the protostar. Magnetic fields could be responsible for the slow infall velocity. A possible scenario of Keplerian disk formation is discussed.

  18. An ALMA Early Science survey of molecular absorption lines toward PKS 1830-211. Analysis of the absorption profiles

    NASA Astrophysics Data System (ADS)

    Muller, S.; Combes, F.; Guélin, M.; Gérin, M.; Aalto, S.; Beelen, A.; Black, J. H.; Curran, S. J.; Darling, J.; V-Trung, Dinh; García-Burillo, S.; Henkel, C.; Horellou, C.; Martín, S.; Martí-Vidal, I.; Menten, K. M.; Murphy, M. T.; Ott, J.; Wiklind, T.; Zwaan, M. A.

    2014-06-01

    We present the first results of an ALMA spectral survey of strong absorption lines for common interstellar species in the z = 0.89 molecular absorber toward the lensed blazar PKS 1830-211. The dataset brings essential information on the structure and composition of the absorbing gas in the foreground galaxy. In particular, we find absorption over large velocity intervals (≳100 km s-1) toward both lensed images of the blazar. This suggests either that the galaxy inclination is intermediate and that we sample velocity gradients or streaming motions in the disk plane, that the molecular gas has a large vertical distribution or extraplanar components, or that the absorber is not a simple spiral galaxy but might be a merger system. The number of detected species is now reaching a total of 42 different species plus 14 different rare isotopologues toward the SW image, and 14 species toward the NE line-of-sight. The abundances of CH, H2O, HCO+, HCN, and NH3 relative to H2 are found to be comparable to those in the Galactic diffuse medium. Of all the lines detected so far toward PKS 1830-211, the ground-state line of ortho-water has the deepest absorption. We argue that ground-state lines of water have the best potential for detecting diffuse molecular gas in absorption at high redshift. Appendix is available in electronic form at http://www.aanda.orgThe reduced spectrum (FITS format) is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/566/A112

  19. ALMA Observations of the Transition from Infall Motion to Keplerian Rotation around the Late-phase Protostar TMC-1A

    NASA Astrophysics Data System (ADS)

    Aso, Yusuke; Ohashi, Nagayoshi; Saigo, Kazuya; Koyamatsu, Shin; Aikawa, Yuri; Hayashi, Masahiko; Machida, Masahiro N.; Saito, Masao; Takakuwa, Shigehisa; Tomida, Kengo; Tomisaka, Kohji; Yen, Hsi-Wei

    2015-10-01

    We have observed the Class I protostar TMC-1A with the Atacama Millimeter/submillimeter Array (ALMA) in the emissions of 12CO and C18O (J = 2-1) and 1.3 mm dust continuum. Continuum emission with a deconvolved size of 0.″50 × 0.″37, perpendicular to the 12CO outflow, is detected. It most likely traces a circumstellar disk around TMC-1A, as previously reported. In contrast, a more extended structure is detected in C18O, although it is still elongated with a deconvolved size of 3.″3 × 2.″2, indicating that C18O traces mainly a flattened envelope surrounding the disk and the central protostar. C18O shows a clear velocity gradient perpendicular to the outflow at higher velocities, indicative of rotation, while an additional velocity gradient along the outflow is found at lower velocities. The radial profile of the rotational velocity is analyzed in detail, finding that it is given as a power law ∝r-a with an index of ˜0.5 at higher velocities. This indicates that the rotation at higher velocities can be explained as Keplerian rotation orbiting a protostar with a dynamical mass of 0.68 {M}⊙ (inclination corrected). The additional velocity gradient of C18O along the outflow is considered to be mainly infall motions in the envelope. Position-velocity diagrams made from models consisting of an infalling envelope and a Keplerian disk are compared with the observations, revealing that the observed infall velocity is ˜0.3 times smaller than the free-fall velocity yielded by the dynamical mass of the protostar. Magnetic fields could be responsible for the slow infall velocity. A possible scenario of Keplerian disk formation is discussed.

  20. ALMA Observations of the Galactic Center: SiO Outflows and High Mass Star Formation Near Sgr A

    NASA Technical Reports Server (NTRS)

    Yusef-Zadeh, F.; Royster, M.; Wardle, M.; Arendt, R.; Bushouse, H.; Gillessen, S.; Lis, D.; Pound, M. W.; Roberts, D. A.; Whitney, B.; Wooten, A.

    2013-01-01

    Using ALMA observations of the Galactic center with a spatial resolution of 2.61" x 0.97 ", we detected 11 SiO (5-4) clumps of molecular gas in the within 0.6pc (15") of Sgr A*, interior of the 2-pc circumnuclear molecular ring. Three SiO (5-4) clumps closest to Sgr A* show the largest central velocities of approximately 150 kilometers per second and broadest asymmetric linewidths with total linewidths FWZI approximately 110-147 kilometers per second. Other clumps are distributed mainly to the NE of the ionized minispiral with narrow linewidths of FWHM approximately 11-27 kilometers per second. Using CARMA data, LVG modeling of the broad velocity clumps, the SiO (5-4) and (2-1) line ratios constrain the column density N(SiO) approximately 10(exp 14) per square centimeter, and the H2 gas density n(sub H2) = (3-9) x 10(exp 5) per cubic centimeter for an assumed kinetic temperature 100-200K. The SiO (5-4) clumps with broad and narrow linewidths are interpreted as highly embedded protostellar outflows, signifying an early stage of massive star formation near Sgr A* in the last 104 years. Additional support for the presence of YSO outflows is that the luminosities and velocity widths lie in the range detected from protostellar outflows in star forming regions in the Galaxy. Furthermore, SED modeling of stellar sources along the N arm show two YSO candidates near SiO clumps supporting in-situ star formation near Sgr A*. We discuss the nature of star formation where the gravitational potential of the black hole dominates. In particular, we suggest that external radiative pressure exerted on self-shielded molecular clouds enhance the gas density, before the gas cloud become gravitationally unstable near Sgr A*.

  1. 66 antennas, up to 16km baselines, 5000m elevation, 28 km from support: the coming challenge of ALMA Observatory antenna group operations and maintenance

    NASA Astrophysics Data System (ADS)

    Chalmers, Dean; Daruich, Felipe; Hoff, Brian; Jara, Cristobal

    2012-09-01

    The ALMA Observatory is under construction at 5000 m above sea level on the Chajnantor plateau located in the Atacama Desert, Chile. When complete it will be comprised of 66 parabolic reflector antennas that can be configured in various arrays using a subset of 192 different stations with baselines from 15 to 16,000 m. The Antenna Group in the ALMA Department of Engineering is responsible for maintenance of the antenna mechanical, control and structural systems, antenna relocations and mechanical aspects of astronomical instrumentation exchanges. The large number of antennas, expanse, elevation, weather conditions of the Array Operation Site (AOS) and its distance from the Operations Support Facility (OSF) will make operations and maintenance for the Antenna Group a challenge. Currently, approximately half of the antennas are in place at the AOS and the first period of Early Science is underway. Operational strategies and specialized equipment developed for preventive and corrective maintenance, array reconfiguration and weather event response are being put to the test and revised based on real experience. This paper explains the operational environment, the constraints it imposes, some of the strategies and specialized equipment being developed to reduce reaction time and resources needed to maintain the array and maximize availability for science operations.

  2. ALMA DETECTION OF THE VIBRATIONALLY EXCITED HCN J = 4-3 EMISSION LINE IN THE AGN-HOSTING LUMINOUS INFRARED GALAXY IRAS 20551–4250

    SciTech Connect

    Imanishi, Masatoshi; Nakanishi, Kouichiro

    2013-10-01

    We present results from our ALMA Cycle 0 observations, at the frequencies around the HCN, HCO{sup +}, and HNC J = 4-3 transition lines, of the luminous infrared galaxy IRAS 20551–4250 at z = 0.043, which is known to host an energetically important obscured active galactic nucleus (AGN). In addition to the targeted HCN, HCO{sup +}, and HNC J = 4-3 emission lines, two additional strong emission lines are seen, which we attribute to H{sub 2}S and CH{sub 3}CN(+CCH). The HCN-to-HCO{sup +} J = 4-3 flux ratio (∼0.7) is higher than in the other starburst-dominated galaxy (∼0.2) observed in our ALMA Cycle 0 program. We tentatively (∼5σ) detected the vibrationally excited (v {sub 2} = 1) HCN J = 4-3 (l = 1f) emission line, which is important for testing an infrared radiative pumping scenario for HCN. This is the second detection of this molecular transition in external galaxies. The most likely reason for this detection is not only the high flux of this emission line, but also the small molecular line widths observed in this galaxy, suggesting that vibrational excitation of HCN may be relatively common in AGN-hosting galaxies.

  3. ALMA OBSERVATIONS OF THE GALACTIC CENTER: SiO OUTFLOWS AND HIGH-MASS STAR FORMATION NEAR Sgr A*

    SciTech Connect

    Yusef-Zadeh, F.; Royster, M.; Roberts, D. A.; Wardle, M.; Arendt, R.; Lis, D. C.; Pound, M. W.; Whitney, B.; Wootten, A.

    2013-04-20

    ALMA observations of the Galactic center with a spatial resolution of 2.''61 Multiplication-Sign 0.''97 resulted in the detection of 11 SiO (5-4) clumps of molecular gas within 0.6 pc (15'') of Sgr A*, interior to the 2 pc circumnuclear molecular ring. The three SiO (5-4) clumps closest to Sgr A* show the largest central velocities, {approx}150 km s{sup -1}, and the broadest asymmetric line widths with full width zero intensity (FWZI) {approx}110-147 km s{sup -1}. The remaining clumps, distributed mainly to the NE of the ionized mini-spiral, have narrow FWZI ({approx}18-56 km s{sup -1}). Using CARMA SiO (2-1) data, Large Velocity Gradient modeling of the SiO line ratios for the broad velocity clumps constrains the column density N(SiO) {approx}10{sup 14} cm{sup -2}, and the H{sub 2} gas density n{sub H{sub 2}} = (3-9) x 10{sup 5} cm{sup -3} for an assumed kinetic temperature 100-200 K. The SiO clumps are interpreted as highly embedded protostellar outflows, signifying an early stage of massive star formation near Sgr A* in the last 10{sup 4}-10{sup 5} yr. Support for this interpretation is provided by the SiO (5-4) line luminosities and velocity widths which lie in the range measured for protostellar outflows in star-forming regions in the Galaxy. Furthermore, spectral energy distribution modeling of stellar sources shows two young stellar object candidates near SiO clumps, supporting in situ star formation near Sgr A*. We discuss the nature of star formation where the gravitational potential of the black hole dominates. In particular, we suggest that external radiative pressure exerted on self-shielded molecular clouds enhances the gas density, before the gas cloud becomes gravitationally unstable near Sgr A*. Alternatively, collisions between clumps in the ring may trigger gravitational collapse.

  4. ALMA: the completion of the 25 Europeans antennas: focus on main performances, problems found during erection and lessons learned

    NASA Astrophysics Data System (ADS)

    Marchiori, Gianpietro; Rampini, Francesco; Giacomel, Luigino; Giacomel, Stefano; Marcuzzi, Enrico; Formentin, Federico

    2014-07-01

    The 2013 saw the completion of the Atacama Large Millimeter Array (ALMA). The array consists of 66 antennas and operates in Chile at the Chajnantor plateau at 5000 m altitude. 25 of the 12 meter diameter antennas have been delivered by the AEM consortium constituted by Thales Alenia Space France, Thales Alenia Space Italy, European Industrial Engineering (EIE GROUP), and MT Mechatronics. The purpose of this paper is to present a summary of the results obtained by the antennas during the different test campaign and a summary of the problems aroused during the erection and the assembly phases and the relative lesson learned. The results of the engineering performances and antenna systems, performed during the acceptance phases of the first antennas, have shown the full correspondence between what was expected during the design phase and what has been achieved in the final product, with a difference of less than 10% and the trend tends to be conservative. As for "on sky antennas performances", all the tests done in the 25 antennas showed excellent results. The antenna All Sky Pointing Error and Offset Pointing Error with and without metrology correction turned to be always excellent. The Fast Motion Capability with the tracking requirements after a step motion was better than an order of magnitude compared to the requests. Four years of on-site activities and the various phases of construction and assembly of 25 antennas have been a major challenge for the European Consortium. The problems encountered in this phase were many and varied: interfaces issues, design and foundation problems, manufacturing and assembly errors, electrical installation, shipment delays, human errors, adverse weather conditions, financial aspects, schedule, etc. The important is being prepared with an "a priori", that is a risk assessment which helps ensuring the best solution for the complete customer satisfaction of the scientific and technical requests. Despite the already excellent

  5. Exploring molecular complexity with ALMA (EMoCA): Deuterated complex organic molecules in Sagittarius B2(N2)

    NASA Astrophysics Data System (ADS)

    Belloche, A.; Müller, H. S. P.; Garrod, R. T.; Menten, K. M.

    2016-03-01

    Context. Deuteration is a powerful tracer of the history of the cold prestellar phase in star-forming regions. Apart from methanol, little is known about deuterium fractionation of complex organic molecules in the interstellar medium, especially in regions forming high-mass stars. Aims: Our goal is to detect deuterated complex organic molecules toward the high mass star-forming region Sagittarius B2 (Sgr B2) and derive the level of deuteration for these molecules. Methods: We use a complete 3-mm spectral line survey performed with the Atacama Large Millimeter/submillimeter Array (ALMA) to search for deuterated complex organic molecules toward the hot molecular core Sgr B2(N2). We constructed population diagrams and integrated intensity maps to fit rotational temperatures and emission sizes for each molecule. Column densities are derived by modeling the full spectrum under the assumption of local thermodynamic equilibrium. We compare the results to predictions of two astrochemical models that treat the deuteration process. Results: We report the detection of CH2DCN toward Sgr B2(N2) with a deuteration level of 0.4%, and tentative detections of CH2DOH, CH2DCH2CN, the chiral molecule CH3CHDCN, and DC3N with levels in the range 0.05%-0.12%. A stringent deuteration upper limit is obtained for CH3OD (<0.07%). Upper limits in the range 0.5-1.8% are derived for the three deuterated isotopologues of vinyl cyanide, the four deuterated species of ethanol, and CH2DOCHO. Ethyl cyanide is less deuterated than methyl cyanide by at least a factor five. The [CH2DOH]/[CH3OD] abundance ratio is higher than 1.8. It may still be consistent with the value obtained in Orion KL. Except for methyl cyanide, the measured deuteration levels lie at least a factor four below the predictions of current astrochemical models. The deuteration levels in Sgr B2(N2) are also lower than in Orion KL by a factor of a few up to a factor ten. Conclusions: The discrepancy between the deuteration levels of

  6. Bright [C ii] and Dust Emission in Three z > 6.6 Quasar Host Galaxies Observed by ALMA

    NASA Astrophysics Data System (ADS)

    Venemans, Bram P.; Walter, Fabian; Zschaechner, Laura; Decarli, Roberto; De Rosa, Gisella; Findlay, Joseph R.; McMahon, Richard G.; Sutherland, Will J.

    2016-01-01

    We present ALMA detections of the [C ii] 158 μm emission line and the underlying far-infrared (FIR) continuum of three quasars at 6.6 < z < 6.9 selected from the VIKING survey. The [C ii] line fluxes range between 1.6 and 3.4 Jy km s-1 ([C ii] luminosities ˜(1.9-3.9) × 109 L⊙). We measure continuum flux densities of 0.56-3.29 mJy around 158 μm (rest frame), with implied FIR luminosities of (0.6-7.5) × 1012 L⊙ and dust masses Md = (0.7-24) × 108 M⊙. In one quasar we derive a dust temperature of {30}-9+12 K from the continuum slope, below the canonical value of 47 K. Assuming that the [C ii] and continuum emission are powered by star formation, we find star formation rates from 100 to 1600 M⊙ yr-1 based on local scaling relations. The L[C ii]/LFIR ratios in the quasar hosts span a wide range from (0.3-4.6) × 10-3, including one quasar with a ratio that is consistent with local star-forming galaxies. We find that the strength of the L[C ii] and 158 μm continuum emission in z ≳ 6 quasar hosts correlates with the quasar’s bolometric luminosity. In one quasar, the [C ii] line is significantly redshifted by ˜1700 km s-1 with respect to the Mg ii broad emission line. Comparing to values in the literature, we find that, on average, the Mg ii is blueshifted by 480 km s-1 (with a standard deviation of 630 km s-1) with respect to the host galaxy redshift, i.e., one of our quasars is an extreme outlier. Through modeling we can rule out a flat rotation curve for our brightest [C ii] emitter. Finally, we find that the ratio of black hole mass to host galaxy (dynamical) mass is higher by a factor of 3-4 (with significant scatter) than local relations.

  7. Warm water deuterium fractionation in IRAS 16293-2422. The high-resolution ALMA and SMA view

    NASA Astrophysics Data System (ADS)

    Persson, M. V.; Jørgensen, J. K.; van Dishoeck, E. F.

    2013-01-01

    Context. Measuring the water deuterium fractionation in the inner warm regions of low-mass protostars has so far been hampered by poor angular resolution obtainable with single-dish ground- and space-based telescopes. Observations of water isotopologues using (sub)millimeter wavelength interferometers have the potential to shed light on this matter. Aims: To measure the water deuterium fractionation in the warm gas of the deeply-embedded protostellar binary IRAS 16293-2422. Methods: Observations toward IRAS 16293-2422 of the 53,2 - 44,1 transition of H218O at 692.07914 GHz from Atacama Large Millimeter/submillimeter Array (ALMA) as well as the 31,3 - 22,0 of H218O at 203.40752 GHz and the 31,2 - 22,1 transition of HDO at 225.89672 GHz from the Submillimeter Array (SMA) are presented. Results: The 692 GHz H218O line is seen toward both components of the binary protostar. Toward one of the components, "source B", the line is seen in absorption toward the continuum, slightly red-shifted from the systemic velocity, whereas emission is seen off-source at the systemic velocity. Toward the other component, "source A", the two HDO and H218O lines are detected as well with the SMA. From the H218O transitions the excitation temperature is estimated at 124 ± 12 K. The calculated HDO/H2O ratio is (9.2 ± 2.6) × 10-4 - significantly lower than previous estimates in the warm gas close to the source. It is also lower by a factor of ~5 than the ratio deduced in the outer envelope. Conclusions: Our observations reveal the physical and chemical structure of water vapor close to the protostars on solar-system scales. The red-shifted absorption detected toward source B is indicative of infall. The excitation temperature is consistent with the picture of water ice evaporation close to the protostar. The low HDO/H2O ratio deduced here suggests that the differences between the inner regions of the protostars and the Earth's oceans and comets are smaller than previously thought

  8. ALMA's view of the nearest neighbors to the Sun. The submm/mm SEDs of the α Centauri binary and a new source

    NASA Astrophysics Data System (ADS)

    Liseau, R.; De la Luz, V.; O'Gorman, E.; Bertone, E.; Chavez, M.; Tapia, F.

    2016-10-01

    Context. The precise mechanisms that provide the nonradiative energy for heating the chromosphere and corona of the Sun and other stars are at the focus of intense contemporary research. Aims: Observations at submm and mm wavelengths are particularly useful to obtain information about the run of the temperature in the upper atmosphere of Sun-like stars. We used the Atacama Large Millimeter/submillimeter Array (ALMA) to study the chromospheric emission of the α Centauri binary system in all six available frequency bands during Cycle 2 in 2014-2015. Methods: Since ALMA is an interferometer, the multitelescope array is particularly suited for the observation of point sources. With its large collecting area, the sensitivity is high enough to allow the observation of nearby main-sequence stars at submm/mm wavelengths for the first time. The comparison of the observed spectral energy distributions with theoretical model computations provides the chromospheric structure in terms of temperature and density above the stellar photosphere and the quantitative understanding of the primary emission processes. Results: Both stars in the α Centauri binary system were detected and resolved at all ALMA frequencies. For both α Cen A and B, the existence and location of the temperature minima, first detected from space with Herschel, are well reproduced by the theoretical models of this paper. The temperature minimum for α Cen B is lower than for A and occurs at a lower height in the atmosphere, but for both stars, Tmin/Teff is consistently lower than what is derived from optical and UV data. In addition, and as a completely different matter, a third point source was detected in Band 8 (405 GHz, 740 μm) in 2015. With only one epoch and only one detection, we are left with little information regarding that object's nature, but we conjecture that it might be a distant solar system object. Conclusions: The submm/mm emission of the α Cen stars is indeed very well reproduced by

  9. Deep ALMA imaging of the merger NGC 1614. Is CO tracing a massive inflow of non-starforming gas?

    NASA Astrophysics Data System (ADS)

    König, S.; Aalto, S.; Muller, S.; Gallagher, J. S.; Beswick, R. J.; Xu, C. K.; Evans, A.

    2016-10-01

    Aims: Observations of the molecular gas over scales of ~0.5 to several kpc provide crucial information on how molecular gas moves through galaxies, especially in mergers and interacting systems, where it ultimately reaches the galaxy center, accumulates, and feeds nuclear activity. Studying the processes involved in the gas transport is one of the important steps forward to understand galaxy evolution. Methods: 12CO, 13CO, and C18O 1-0 high-sensitivity ALMA observations (~4'' × 2'') were used to assess the properties of the large-scale molecular gas reservoir and its connection to the circumnuclear molecular ring in the merger NGC 1614. Specifically, the role of excitation and abundances were studied in this context. We also observed the molecular gas high-density tracers CN and CS. Results: The spatial distributions of the detected 12CO 1-0 and 13CO 1-0 emission show significant differences. 12CO traces the large-scale molecular gas reservoir, which is associated with a dust lane that harbors infalling gas, and extends into the southern tidal tails. 13CO emission is for the first time detected in the large-scale dust lane. In contrast to 12CO, its line emission peaks between the dust lane and the circumnuclear molecular ring. A 12CO-to-13CO 1-0 intensity ratio map shows high values in the ring region (~30) that are typical for the centers of luminous galaxy mergers and even more extreme values in the dust lane (>45). Surprisingly, we do not detect C18O emission in NGC 1614, but we do observe gas emitting the high-density tracers CN and CS. Conclusions: We find that the 12CO-to-13CO 1-0 line ratio in NGC 1614 changes from >45 in the 2 kpc dust lane to ~30 in the starburst nucleus. This drop in ratio with decreasing radius is consistent with the molecular gas in the dust lane being kept in a diffuse, unbound state while it is being funneled toward the nucleus. This also explains why there are no (or very faint) signs of star formation in the dust lane, despite its

  10. Exploring molecular complexity with ALMA (EMoCA): Alkanethiols and alkanols in Sagittarius B2(N2)

    NASA Astrophysics Data System (ADS)

    Müller, Holger S. P.; Belloche, Arnaud; Xu, Li-Hong; Lees, Ronald M.; Garrod, Robin T.; Walters, Adam; van Wijngaarden, Jennifer; Lewen, Frank; Schlemmer, Stephan; Menten, Karl M.

    2016-03-01

    Context. Over the past five decades, radio astronomy has shown that molecular complexity is a natural outcome of interstellar chemistry, in particular in star forming regions. However, the pathways that lead to the formation of complex molecules are not completely understood and the depth of chemical complexity has not been entirely revealed. In addition, the sulfur chemistry in the dense interstellar medium is not well understood. Aims: We want to know the relative abundances of alkanethiols and alkanols in the Galactic center source Sagittarius B2(N2), the northern hot molecular core in Sgr B2(N), whose relatively small line widths are favorable for studying the molecular complexity in space. Methods: We investigated spectroscopic parameter sets that were able to reproduce published laboratory rotational spectra of ethanethiol and studied effects that modify intensities in the predicted rotational spectrum of ethanol. We used the Atacama Large Millimeter Array (ALMA) in its Cycles 0 and 1 for a spectral line survey of Sagittarius B2(N) between 84 and 114.4 GHz. These data were analyzed by assuming local thermodynamic equilibrium (LTE) for each molecule. Our observations are supplemented by astrochemical modeling; a new network is used that includes reaction pathways for alkanethiols for the first time. Results: We detected methanol and ethanol in their parent 12C species and their isotopologs with one 12C atom substituted by 13C; the latter were detected for the first time unambiguously in the case of ethanol. The 12C/13C ratio is ~25 for both molecules. In addition, we identified CH318 OH with a 16O/18O ratio of ~180 and a 13CH3OH/CH318 OH ratio of ~7.3. Upper limits were derived for the next larger alkanols normal- and iso-propanol. We observed methanethiol, CH3SH, also known as methyl mercaptan, including torsionally excited transitions for the first time. We also identified transitions of ethanethiol (or ethyl mercaptan), though not enough to claim a secure

  11. ALMA OBSERVATIONS OF WARM DENSE GAS IN NGC 1614—BREAKING OF THE STAR FORMATION LAW IN THE CENTRAL KILOPARSEC

    SciTech Connect

    Xu, C. K.; Cao, C.; Lu, N.; Diaz-Santos, T.; Zhao, Y.-H.; Mazzarella, J. M.; Appleton, P.; Armus, L.; Murphy, E. J.; Gao, Y.; Herrero-Illana, R.; Privon, G.; Evans, A. S.; König, S.; Aalto, S.; Charmandaris, V.; Chu, J.; Haan, S.; Inami, H.; and others

    2015-01-20

    We present ALMA Cycle-0 observations of the CO (6-5) line emission and of the 435 μm dust continuum emission in the central kiloparsec of NGC 1614, a local luminous infrared galaxy at a distance of 67.8 Mpc (1{sup ′′}=329 pc). The CO emission is well resolved by the ALMA beam (0.''26 × 0.''20) into a circumnuclear ring, with an integrated flux of f {sub CO(6-5)} = 898 (± 153) Jy km s{sup –1}, which is 63(± 12)% of the total CO (6-5) flux measured by Herschel. The molecular ring, located between 100 pc

  12. ALMA Observations of Warm Dense Gas in NGC 1614—Breaking of the Star Formation Law in the Central Kiloparsec

    NASA Astrophysics Data System (ADS)

    Xu, C. K.; Cao, C.; Lu, N.; Gao, Y.; Diaz-Santos, T.; Herrero-Illana, R.; Meijerink, R.; Privon, G.; Zhao, Y.-H.; Evans, A. S.; König, S.; Mazzarella, J. M.; Aalto, S.; Appleton, P.; Armus, L.; Charmandaris, V.; Chu, J.; Haan, S.; Inami, H.; Murphy, E. J.; Sanders, D. B.; Schulz, B.; van der Werf, P.

    2015-01-01

    We present ALMA Cycle-0 observations of the CO (6-5) line emission and of the 435 μm dust continuum emission in the central kiloparsec of NGC 1614, a local luminous infrared galaxy at a distance of 67.8 Mpc (1{\\prime \\prime }= 329 pc). The CO emission is well resolved by the ALMA beam (0.''26 × 0.''20) into a circumnuclear ring, with an integrated flux of f CO(6-5) = 898 (± 153) Jy km s-1, which is 63(± 12)% of the total CO (6-5) flux measured by Herschel. The molecular ring, located between 100 pc < r < 350 pc from the nucleus, looks clumpy and includes seven unresolved (or marginally resolved) knots with median velocity dispersion of ~40 km s-1. These knots are associated with strong star formation regions with ΣSFR ~ 100 M ⊙ yr-1 kpc-2 and Σ Gas˜ 104 {M}_⊙ pc-2. The non-detections of the nucleus in both the CO (6-5) line emission and the 435 μm continuum rule out, with relatively high confidence, a Compton-thick active galactic nucleus in NGC 1614. Comparisons with radio continuum emission show a strong deviation from an expected local correlation between ΣGas and ΣSFR, indicating a breakdown of the Kennicutt-Schmidt law on the linear scale of ~100 pc. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

  13. ALMA observations of the host galaxy of GRB 090423 at z = 8.23: deep limits on obscured star formation 630 million years after the big bang

    SciTech Connect

    Berger, E.; Zauderer, B. A.; Chary, R.-R.; Laskar, T.; Chornock, R.; Davies, J. E.; Tanvir, N. R.; Stanway, E. R.; Levan, A. J.; Levesque, E. M.

    2014-12-01

    We present rest-frame far-infrared (FIR) and optical observations of the host galaxy of GRB 090423 at z = 8.23 from the Atacama Large Millimeter Array (ALMA) and the Spitzer Space Telescope, respectively. The host remains undetected to 3σ limits of F {sub ν}(222 GHz) ≲ 33 μJy and F {sub ν}(3.6 μm) ≲ 81 nJy. The FIR limit is about 20 times fainter than the luminosity of the local ULIRG Arp 220 and comparable to the local starburst M 82. Comparing this with model spectral energy distributions, we place a limit on the infrared (IR) luminosity of L {sub IR}(8-1000 μm) ≲ 3 × 10{sup 10} L {sub ☉}, corresponding to a limit on the obscured star formation rate of SFR{sub IR}≲5 M {sub ☉} yr{sup –1}. For comparison, the limit on the unobscured star formation rate from Hubble Space Telescope rest-frame ultraviolet (UV) observations is SFR{sub UV} ≲ 1 M {sub ☉} yr{sup –1}. We also place a limit on the host galaxy stellar mass of M {sub *} ≲ 5 × 10{sup 7} M {sub ☉} (for a stellar population age of 100 Myr and constant star formation rate). Finally, we compare our millimeter observations to those of field galaxies at z ≳ 4 (Lyman break galaxies, Lyα emitters, and submillimeter galaxies) and find that our limit on the FIR luminosity is the most constraining to date, although the field galaxies have much larger rest-frame UV/optical luminosities than the host of GRB 090423 by virtue of their selection techniques. We conclude that GRB host galaxies at z ≳ 4, especially those with measured interstellar medium metallicities from afterglow spectroscopy, are an attractive sample for future ALMA studies of high redshift obscured star formation.

  14. Radio Jet Feedback and Star Formation in Heavily Obscured, Hyperluminous Quasars at Redshifts ∼ 0.5–3. I. ALMA Observations

    NASA Astrophysics Data System (ADS)

    Lonsdale, Carol J.; Lacy, M.; Kimball, A. E.; Blain, A.; Whittle, M.; Wilkes, B.; Stern, D.; Condon, J.; Kim, M.; Assef, R. J.; Tsai, C.-W.; Efstathiou, A.; Jones, S.; Eisenhardt, P.; Bridge, C.; Wu, J.; Lonsdale, Colin J.; Jones, K.; Jarrett, T.; Smith, R.

    2015-11-01

    We present Atacama Large Millimeter/submillimeter Array (ALMA) 870 μm (345 GHz) data for 49 high-redshift (0.47 < z < 2.85), luminous (11.7\\lt {log}({L}{{bol}}/{L}ȯ )\\lt 14.2) radio-powerful active galactic nuclei (AGNs), obtained to constrain cool dust emission from starbursts concurrent with highly obscured radiative-mode black hole (BH) accretion in massive galaxies that possess a small radio jet. The sample was selected from the Wide-field Infrared Survey Explorer with extremely steep (red) mid-infrared colors and with compact radio emission from NVSS/FIRST. Twenty-six sources are detected at 870 μm, and we find that the sample has large mid- to far-infrared luminosity ratios, consistent with a dominant and highly obscured quasar. The rest-frame 3 GHz radio powers are 24.7\\lt {log}({P}\\text{3.0 GHz}/{{{W}} {Hz}}-1)\\lt 27.3, and all sources are radio-intermediate or radio-loud. BH mass estimates are 7.7 < log(MBH/M⊙) < 10.2. The rest-frame 1–5 μm spectral energy distributions are very similar to the “Hot DOGs” (hot dust-obscured galaxies), and steeper (redder) than almost any other known extragalactic sources. ISM masses estimated for the ALMA-detected sources are 9.9 < log (MISM/M⊙) < 11.75 assuming a dust temperature of 30 K. The cool dust emission is consistent with star formation rates reaching several thousand M⊙ yr‑1, depending on the assumed dust temperature, but we cannot rule out the alternative that the AGN powers all the emission in some cases. Our best constrained source has radiative transfer solutions with approximately equal contributions from an obscured AGN and a young (10–15 Myr) compact starburst.

  15. Radio Jet Feedback and Star Formation in Heavily Obscured, Hyperluminous Quasars at Redshifts ˜ 0.5-3. I. ALMA Observations

    NASA Astrophysics Data System (ADS)

    Lonsdale, Carol J.; Lacy, M.; Kimball, A. E.; Blain, A.; Whittle, M.; Wilkes, B.; Stern, D.; Condon, J.; Kim, M.; Assef, R. J.; Tsai, C.-W.; Efstathiou, A.; Jones, S.; Eisenhardt, P.; Bridge, C.; Wu, J.; Lonsdale, Colin J.; Jones, K.; Jarrett, T.; Smith, R.

    2015-11-01

    We present Atacama Large Millimeter/submillimeter Array (ALMA) 870 μm (345 GHz) data for 49 high-redshift (0.47 < z < 2.85), luminous (11.7\\lt {log}({L}{{bol}}/{L}⊙ )\\lt 14.2) radio-powerful active galactic nuclei (AGNs), obtained to constrain cool dust emission from starbursts concurrent with highly obscured radiative-mode black hole (BH) accretion in massive galaxies that possess a small radio jet. The sample was selected from the Wide-field Infrared Survey Explorer with extremely steep (red) mid-infrared colors and with compact radio emission from NVSS/FIRST. Twenty-six sources are detected at 870 μm, and we find that the sample has large mid- to far-infrared luminosity ratios, consistent with a dominant and highly obscured quasar. The rest-frame 3 GHz radio powers are 24.7\\lt {log}({P}\\text{3.0 GHz}/{{{W}} {Hz}}-1)\\lt 27.3, and all sources are radio-intermediate or radio-loud. BH mass estimates are 7.7 < log(MBH/M⊙) < 10.2. The rest-frame 1-5 μm spectral energy distributions are very similar to the “Hot DOGs” (hot dust-obscured galaxies), and steeper (redder) than almost any other known extragalactic sources. ISM masses estimated for the ALMA-detected sources are 9.9 < log (MISM/M⊙) < 11.75 assuming a dust temperature of 30 K. The cool dust emission is consistent with star formation rates reaching several thousand M⊙ yr-1, depending on the assumed dust temperature, but we cannot rule out the alternative that the AGN powers all the emission in some cases. Our best constrained source has radiative transfer solutions with approximately equal contributions from an obscured AGN and a young (10-15 Myr) compact starburst.

  16. ALMA Observation of 158 μm [C II] Line and Dust Continuum of a z = 7 Normally Star-forming Galaxy in the Epoch of Reionization

    NASA Astrophysics Data System (ADS)

    Ota, Kazuaki; Walter, Fabian; Ohta, Kouji; Hatsukade, Bunyo; Carilli, Chris L.; da Cunha, Elisabete; González-López, Jorge; Decarli, Roberto; Hodge, Jacqueline A.; Nagai, Hiroshi; Egami, Eiichi; Jiang, Linhua; Iye, Masanori; Kashikawa, Nobunari; Riechers, Dominik A.; Bertoldi, Frank; Cox, Pierre; Neri, Roberto; Weiss, Axel

    2014-09-01

    We present ALMA observations of the [C II] line and far-infrared (FIR) continuum of a normally star-forming galaxy in the reionization epoch, the z = 6.96 Lyα emitter (LAE) IOK-1. Probing to sensitivities of σline = 240 μJy beam-1 (40 km s-1 channel) and σcont = 21 μJy beam-1, we found the galaxy undetected in both [C II] and continuum. Comparison of ultraviolet (UV)-FIR spectral energy distribution (SED) of IOK-1, including our ALMA limit, with those of several types of local galaxies (including the effects of the cosmic microwave background, CMB, on the FIR continuum) suggests that IOK-1 is similar to local dwarf/irregular galaxies in SED shape rather than highly dusty/obscured galaxies. Moreover, our 3σ FIR continuum limit, corrected for CMB effects, implies intrinsic dust mass M dust < 6.4 × 107 M ⊙, FIR luminosity L FIR < 3.7 × 1010 L ⊙ (42.5-122.5 μm), total IR luminosity L IR < 5.7 × 1010 L ⊙ (8-1000 μm), and dust-obscured star formation rate (SFR) < 10 M ⊙ yr-1, if we assume that IOK-1 has a dust temperature and emissivity index typical of local dwarf galaxies. This SFR is 2.4 times lower than one estimated from the UV continuum, suggesting that <29% of the star formation is obscured by dust. Meanwhile, our 3σ [C II] flux limit translates into [C II] luminosity, L [C II] < 3.4 × 107 L ⊙. Locations of IOK-1 and previously observed LAEs on the L [C II] versus SFR and L [C II]/L FIR versus L FIR diagrams imply that LAEs in the reionization epoch have significantly lower gas and dust enrichment than AGN-powered systems and starbursts at similar/lower redshifts, as well as local star-forming galaxies. Based in part on data collected with the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan; observations made with the NASA/ESA Hubble Space Telescope, obtained from the Data Archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc

  17. ALMA Observations of a High-density Core in Taurus: Dynamical Gas Interaction at the Possible Site of a Multiple Star Formation

    NASA Astrophysics Data System (ADS)

    Tokuda, Kazuki; Onishi, Toshikazu; Saigo, Kazuya; Kawamura, Akiko; Fukui, Yasuo; Matsumoto, Tomoaki; Inutsuka, Shu-ichiro; Machida, Masahiro N.; Tomida, Kengo; Tachihara, Kengo

    2015-08-01

    It is crucially important to observe dense cores in order to investigate the initial condition of star formation since protostars are formed via dynamical collapse of dense cores, inhering the physical properties from their natal dense cores. Here we present the results of ALMA Cycle 0 and Cycle 1 observations of dust continuum emission and molecular rotational lines toward a dense core, MC27 (aka L1521F), which is considered to be very close to the first protostellar core phase.The Cycle 0 observations revealed complex structures at the center. We found a few starless high-density cores, one of which (MMS2) has a very high density of ~107 cm-3, around the very low-luminousity protostar detected by Spitzer. A very compact bipolar outflow with a dynamical timescale of a few hundred years was found toward the protostar. The HCO+ (3-2) observation shows several cores associated with an arc-like structure whose length is ~2000 AU, possibly due to the dynamical gas interaction. These complex structures suggest that the initial condition of star formation is highly dynamical in nature, which is considered to be a key factor in understanding fundamental issues of star formation such as origins of the stellar multiplicity and the initial mass function. These initial Cycle 0 results were published by Tokuda et al. (2014). Matsumoto et al. (2015) investigated the arc-like structures by performing numerical simulations.Detailed column density distribution with the size from ~100 to ~10000 AU scale are revealed by combining the 12m array data with the 7m array data of the ALMA Compact Array as well as with the single dish MAMBO data. Our preliminary analysis shows that the averaged radial column density distribution of the inner part (r < 2000 AU) is N(H2)~r-0.4, clearly flatter than that of the outer part, ~r-1.3. We detected the above-mentioned complex structure inside the inner flatter region, which may reflect the dynamical status of the dense core. The Cycle 1

  18. ALMA observation of 158 μm [C II] line and dust continuum of a z = 7 normally star-forming galaxy in the epoch of reionization

    SciTech Connect

    Ota, Kazuaki; Walter, Fabian; Da Cunha, Elisabete; González-López, Jorge; Decarli, Roberto; Hodge, Jacqueline A.; Ohta, Kouji; Hatsukade, Bunyo; Nagai, Hiroshi; Iye, Masanori; Kashikawa, Nobunari; Carilli, Chris L.; Egami, Eiichi; Jiang, Linhua; Riechers, Dominik A.; Bertoldi, Frank; Cox, Pierre; Neri, Roberto; Weiss, Axel

    2014-09-01

    We present ALMA observations of the [C II] line and far-infrared (FIR) continuum of a normally star-forming galaxy in the reionization epoch, the z = 6.96 Lyα emitter (LAE) IOK-1. Probing to sensitivities of σ{sub line} = 240 μJy beam{sup –1} (40 km s{sup –1} channel) and σ{sub cont} = 21 μJy beam{sup –1}, we found the galaxy undetected in both [C II] and continuum. Comparison of ultraviolet (UV)-FIR spectral energy distribution (SED) of IOK-1, including our ALMA limit, with those of several types of local galaxies (including the effects of the cosmic microwave background, CMB, on the FIR continuum) suggests that IOK-1 is similar to local dwarf/irregular galaxies in SED shape rather than highly dusty/obscured galaxies. Moreover, our 3σ FIR continuum limit, corrected for CMB effects, implies intrinsic dust mass M {sub dust} < 6.4 × 10{sup 7} M {sub ☉}, FIR luminosity L {sub FIR} < 3.7 × 10{sup 10} L {sub ☉} (42.5-122.5 μm), total IR luminosity L {sub IR} < 5.7 × 10{sup 10} L {sub ☉} (8-1000 μm), and dust-obscured star formation rate (SFR) < 10 M {sub ☉} yr{sup –1}, if we assume that IOK-1 has a dust temperature and emissivity index typical of local dwarf galaxies. This SFR is 2.4 times lower than one estimated from the UV continuum, suggesting that <29% of the star formation is obscured by dust. Meanwhile, our 3σ [C II] flux limit translates into [C II] luminosity, L {sub [C} {sub II]} < 3.4 × 10{sup 7} L {sub ☉}. Locations of IOK-1 and previously observed LAEs on the L {sub [C} {sub II]} versus SFR and L {sub [C} {sub II]}/L {sub FIR} versus L {sub FIR} diagrams imply that LAEs in the reionization epoch have significantly lower gas and dust enrichment than AGN-powered systems and starbursts at similar/lower redshifts, as well as local star-forming galaxies.

  19. ALMA OBSERVATIONS OF A HIGH-DENSITY CORE IN TAURUS: DYNAMICAL GAS INTERACTION AT THE POSSIBLE SITE OF A MULTIPLE STAR FORMATION

    SciTech Connect

    Tokuda, Kazuki; Onishi, Toshikazu; Saigo, Kazuya; Kawamura, Akiko; Fukui, Yasuo; Inutsuka, Shu-ichiro; Tachihara, Kengo; Matsumoto, Tomoaki; Machida, Masahiro N.; Tomida, Kengo

    2014-07-01

    Starless dense cores eventually collapse dynamically, forming protostars inside them, and the physical properties of the cores determine the nature of the forming protostars. We report ALMA observations of dust continuum emission and molecular rotational lines toward MC27 or L1521F, which is considered to be very close to the first protostellar core phase. We found a few starless high-density cores, one of which has a very high density of ∼10{sup 7} cm{sup –3}, within a region of several hundred AU around a very low-luminosity protostar detected by Spitzer. A very compact bipolar outflow with a dynamical timescale of a few hundred years was found toward the protostar. The molecular line observation shows several cores with an arc-like structure, possibly due to the dynamical gas interaction. These complex structures revealed in the present observations suggest that the initial condition of star formation is highly dynamical in nature, which is considered to be a key factor in understanding fundamental issues of star formation such as the formation of multiple stars and the origin of the initial mass function of stars.

  20. Interpreting major industrial landscapes: Social follow-up on meanings, the case of two aluminium smelters, Alcan (Alma, Canada) and Pechiney (Dunkirk, France)

    SciTech Connect

    Fortin, Marie-Jose . E-mail: marie-jose_fortin@uqac.ca; Gagnon, Christiane . E-mail: christiane_gagnon@uqac.ca

    2006-11-15

    Landscape is becoming an object of growing social concern and, as such, an object of mediation between major industrial producers and local communities. The question of the capacity of environmental assessment to address this issue is thus raised. Until now, landscape studies have focused on visual aspects, although subjective dimensions such as perceptions and meanings have been recognised. The research in this article concerns the subjective dimensions, and is presented with a view to further the understanding of the process of the social interpretation of landscape as it relates to heavy industrial sites. Within a socioconstructivist perspective, two case studies (a longitudinal follow-up and an ex-post) of two aluminum smelters, one in Alma (Quebec, Canada) and the other in Dunkirk (France) were conducted. The results show that nearby residents' interpretations of landscape varied according to three sets of factors related to 1) the dynamics of regional development and the historical place of industry in the community, 2) the relationship between residents and the industry and local governance capacities, and 3) the social impacts experienced. To conclude, three ways of using qualitative methodologies for social and environmental follow-up in a socioconstructivist approach to landscape are proposed.

  1. ALMA 0.1-0.2 arcsec Resolution Imaging of the NGC 1068 Nucleus: Compact Dense Molecular Gas Emission at the Putative AGN Location

    NASA Astrophysics Data System (ADS)

    Imanishi, Masatoshi; Nakanishi, Kouichiro; Izumi, Takuma

    2016-05-01

    We present the results of our ALMA Cycle 2 high angular resolution (0.″1-0.″2) observations of the nuclear region of the nearby well-studied type-2 active galactic nucleus (AGN), NGC 1068, at HCN J = 3-2 and HCO+ J = 3-2 emission lines. For the first time, due to a higher angular resolution than previous studies, we clearly detected dense molecular gas emission at the putative AGN location, identified as a ˜1.1 mm (˜266 GHz) continuum emission peak, by separating this emission from brighter emission located at 0.″5-2.″0 on the eastern and western sides of the AGN. The estimated intrinsic molecular emission size and dense molecular mass, which are thought to be associated with the putative dusty molecular torus around an AGN, were ˜10 pc and ˜several × 105 M ⊙, respectively. HCN-to-HCO+ J = 3-2 flux ratios substantially higher than unity were found throughout the nuclear region of NGC 1068. The continuum emission displayed an elongated morphology along the direction of the radio jet located at the northern side of the AGN, as well as a weak spatially-resolved component at ˜2.″0 on the southwestern side of the AGN. The latter component most likely originated from star formation, with the estimated luminosity more than one order of magnitude lower than the luminosity of the central AGN. No vibrationally excited (v 2 = 1f) J = 3-2 emission lines were detected for HCN and HCO+ across the field of view.

  2. Humoral responses of broiler chickens challenged with NDV following supplemental treatment with extracts of Aloe vera, Alma millsoni, Ganoderma lucidum and Archachatina marginata

    PubMed Central

    Eghafona, Nosahkare'Odeh

    2015-01-01

    Aim of the study The significance of nutritional supplements for immunity has been documented. Locally sourced extracts used in alternative medicine were studied to determine their potential effects on antibody production and humoral responses in viral challenged birds. Method Three hundred and eighty birds were distributed into 19 groups of 20 birds each. Following acclimatization for 16 days, they were fed with standard broilers feed and water ad libitum. Group A was supplemented with Aloe vera (AV) extract, group B was given Alma millsoni (AM) extract, group C was given Archachatina marginata (AMS) extract and group D was given Ganoderma lucidum (GL) extract, and group E was the control group. Extract concentrations of 50 mg, 100 mg and 150 mg were given to three subsets of each treatment group for 30 days. Birds were then challenged with intramuscular administration of 0.2 ml of 50% Embryo Lethal Dose of saline suspension of the challenge strain of Newcastle Disease Virus (NDV) on the 30th day, and were examined for clinical signs and symptoms. Serum from venous blood was used for antibody and immunological assay. Results Aloe vera at 50 µg and A. millsoni extracts supplementations yielded a significant antibody titre (p < 0.001). The difference within the AMS, GL and AV groups and the control group was not statistically significant (p < 0.05). Conclusion Unlike the extract of Ganoderma and A. marginata, pretreatment with A. millsoni extract and a lower dosage of Aloe vera enhanced the ability to mount humoral responses against viral infection in broiler chickens. PMID:26648773

  3. ALMA 0.1–0.2 arcsec Resolution Imaging of the NGC 1068 Nucleus: Compact Dense Molecular Gas Emission at the Putative AGN Location

    NASA Astrophysics Data System (ADS)

    俊, Masatoshi Imanishi (今 西 昌; 郎, Kouichiro Nakanishi (中 西 康 一; 磨, Takuma Izumi (泉 拓

    2016-05-01

    We present the results of our ALMA Cycle 2 high angular resolution (0.″1–0.″2) observations of the nuclear region of the nearby well-studied type-2 active galactic nucleus (AGN), NGC 1068, at HCN J = 3–2 and HCO+ J = 3–2 emission lines. For the first time, due to a higher angular resolution than previous studies, we clearly detected dense molecular gas emission at the putative AGN location, identified as a ˜1.1 mm (˜266 GHz) continuum emission peak, by separating this emission from brighter emission located at 0.″5–2.″0 on the eastern and western sides of the AGN. The estimated intrinsic molecular emission size and dense molecular mass, which are thought to be associated with the putative dusty molecular torus around an AGN, were ˜10 pc and ˜several × 105 M ⊙, respectively. HCN-to-HCO+ J = 3–2 flux ratios substantially higher than unity were found throughout the nuclear region of NGC 1068. The continuum emission displayed an elongated morphology along the direction of the radio jet located at the northern side of the AGN, as well as a weak spatially-resolved component at ˜2.″0 on the southwestern side of the AGN. The latter component most likely originated from star formation, with the estimated luminosity more than one order of magnitude lower than the luminosity of the central AGN. No vibrationally excited (v 2 = 1f) J = 3–2 emission lines were detected for HCN and HCO+ across the field of view.

  4. ISM Masses and the Star formation Law at Z = 1 to 6: ALMA Observations of Dust Continuum in 145 Galaxies in the COSMOS Survey Field

    NASA Astrophysics Data System (ADS)

    Scoville, N.; Sheth, K.; Aussel, H.; Vanden Bout, P.; Capak, P.; Bongiorno, A.; Casey, C. M.; Murchikova, L.; Koda, J.; Álvarez-Márquez, J.; Lee, N.; Laigle, C.; McCracken, H. J.; Ilbert, O.; Pope, A.; Sanders, D.; Chu, J.; Toft, S.; Ivison, R. J.; Manohar, S.

    2016-04-01

    ALMA Cycle 2 observations of long-wavelength dust emission in 145 star-forming galaxies are used to probe the evolution of the star-forming interstellar medium (ISM). We also develop a physical basis and empirical calibration (with 72 low-z and z ∼ 2 galaxies) for using the dust continuum as a quantitative probe of ISM masses. The galaxies with the highest star formation rates (SFRs) at < z> = 2.2 and 4.4 have gas masses up to 100 times that of the Milky Way and gas mass fractions reaching 50%–80%, i.e., gas masses 1-4× their stellar masses. We find a single high-z star formation law: {SFR}=35 {M}{mol}0.89× {(1+z)}z=20.95× {({sSFR})}{MS}0.23 {M}ȯ yr‑1—an approximately linear dependence on the ISM mass and an increased star formation efficiency per unit gas mass at higher redshift. Galaxies above the main sequence (MS) have larger gas masses but are converting their ISM into stars on a timescale only slightly shorter than those on the MS; thus, these “starbursts” are largely the result of having greatly increased gas masses rather than an increased efficiency of converting gas to stars. At z > 1, the entire population of star-forming galaxies has ∼2–5 times shorter gas depletion times than low-z galaxies. These shorter depletion times indicate a different mode of star formation in the early universe—most likely dynamically driven by compressive, high-dispersion gas motions—a natural consequence of the high gas accretion rates.

  5. An ALMA survey of submillimeter galaxies in the extended Chandra deep field south: The redshift distribution and evolution of submillimeter galaxies

    SciTech Connect

    Simpson, J. M.; Swinbank, A. M.; Smail, Ian; Alexander, D. M.; Danielson, A. L. R.; Thomson, A. P.; Brandt, W. N.; Bertoldi, F.; Karim, A.; De Breuck, C.; Chapman, S. C.; Coppin, K. E. K.; Da Cunha, E.; Hodge, J. A.; Schinnerer, E.; Dannerbauer, H.; Greve, T. R.; Ivison, R. J.; Knudsen, K. K.; Poggianti, B. M.; and others

    2014-06-20

    We present the first photometric redshift distribution for a large sample of 870 μm submillimeter galaxies (SMGs) with robust identifications based on observations with ALMA. In our analysis we consider 96 SMGs in the Extended Chandra Deep Field South, 77 of which have 4-19 band photometry. We model the SEDs for these 77 SMGs, deriving a median photometric redshift of z {sub phot} = 2.3 ± 0.1. The remaining 19 SMGs have insufficient photometry to derive photometric redshifts, but a stacking analysis of Herschel observations confirms they are not spurious. Assuming that these SMGs have an absolute H-band magnitude distribution comparable to that of a complete sample of z ∼ 1-2 SMGs, we demonstrate that they lie at slightly higher redshifts, raising the median redshift for SMGs to z {sub phot} = 2.5 ± 0.2. Critically we show that the proportion of galaxies undergoing an SMG-like phase at z ≥ 3 is at most 35% ± 5% of the total population. We derive a median stellar mass of M {sub *} = (8 ± 1) × 10{sup 10} M {sub ☉}, although there are systematic uncertainties of up to 5 × for individual sources. Assuming that the star formation activity in SMGs has a timescale of ∼100 Myr, we show that their descendants at z ∼ 0 would have a space density and M{sub H} distribution that are in good agreement with those of local ellipticals. In addition, the inferred mass-weighted ages of the local ellipticals broadly agree with the look-back times of the SMG events. Taken together, these results are consistent with a simple model that identifies SMGs as events that form most of the stars seen in the majority of luminous elliptical galaxies at the present day.

  6. An alma survey of sub-millimeter galaxies in the extended Chandra deep field south: Sub-millimeter properties of color-selected galaxies

    SciTech Connect

    Decarli, R.; Walter, F.; Hodge, J. A.; Rix, H.-W.; Schinnerer, E.; Smail, I.; Swinbank, A. M.; Karim, A.; Simpson, J. M.; Chapman, S.; Coppin, K. E. K.; Cox, P.; Dannerbauer, H.; Greve, T. R.; Ivison, R.; Knudsen, K. K.; Lindroos, L.; Van der Werf, P.; Weiß, A.

    2014-01-10

    We study the sub-millimeter properties of color-selected galaxies via a stacking analysis applied for the first time to interferometric data at sub-millimeter wavelengths. We base our study on 344 GHz ALMA continuum observations of ∼20''-wide fields centered on 86 sub-millimeter sources detected in the LABOCA Extended Chandra Deep Field South (ECDFS) Sub-millimeter Survey. We select various classes of galaxies (K-selected, star-forming sBzK galaxies, extremely red objects, and distant red galaxies) according to their optical/near-infrared fluxes. We find clear, >10σ detections in the stacked images of all these galaxy classes. We include in our stacking analysis Herschel/SPIRE data to constrain the dust spectral energy distribution of these galaxies. We find that their dust emission is well described by a modified blackbody with T {sub dust} ≈ 30 K and β = 1.6 and infrared luminosities of (5-11) × 10{sup 11} L {sub ☉} or implied star formation rates of 75-140 M {sub ☉} yr{sup –1}. We compare our results with those of previous studies based on single-dish observations at 870 μm and find that our flux densities are a factor 2-3 higher than previous estimates. The discrepancy is observed also after removing sources individually detected in ALESS maps. We report a similar discrepancy by repeating our analysis on 1.4 GHz observations of the whole ECDFS. Hence, we find tentative evidence that galaxies that are associated in projected and redshift space with sub-mm bright sources are brighter than the average population. Finally, we put our findings in the context of the cosmic star formation rate density as a function of redshift.

  7. ALMA results of the pseudodisk, rotating disk, and jet in the continuum and HCO{sup +} in the protostellar system HH 212

    SciTech Connect

    Lee, Chin-Fei; Hirano, Naomi; Shang, Hsien; Ho, Paul T. P.; Krasnopolsky, Ruben; Zhang, Qizhou

    2014-05-10

    HH 212 is a nearby (400 pc) Class 0 protostellar system showing several components that can be compared with theoretical models of core collapse. We have mapped it in the 350 GHz continuum and HCO{sup +} J = 4-3 emission with ALMA at up to ∼0.''4 resolution. A flattened envelope and a compact disk are seen in the continuum around the central source, as seen before. The HCO{sup +} kinematics shows that the flattened envelope is infalling with small rotation (i.e., spiraling) into the central source, and thus can be identified as a pseudodisk in the models of magnetized core collapse. Also, the HCO{sup +} kinematics shows that the disk is rotating and can be rotationally supported. In addition, to account for the missing HCO{sup +} emission at low-redshifted velocity, an extended infalling envelope is required, with its material flowing roughly parallel to the jet axis toward the pseudodisk. This is expected if it is magnetized with an hourglass B-field morphology. We have modeled the continuum and HCO{sup +} emission of the flattened envelope and disk simultaneously. We find that a jump in density is required across the interface between the pseudodisk and the disk. A jet is seen in HCO{sup +} extending out to ∼500 AU away from the central source, with the peaks upstream of those seen before in SiO. The broad velocity range and high HCO{sup +} abundance indicate that the HCO{sup +} emission traces internal shocks in the jet.

  8. Morphology and kinematics of the gas envelope of protostar L1527 as obtained from ALMA observations of the C18O(2-1) line emission

    NASA Astrophysics Data System (ADS)

    Tuan-Anh, P.; Nhung, P. T.; Hoai, D. T.; Diep, P. N.; Phuong, N. T.; Thao, N. T.; Darriulat, P.

    2016-09-01

    Using ALMA observations of the C18O(2-1) line emission of the gas envelope of protostar L1527, we have reconstructed its morphology and kinematics under the assumption of axisymmetry about the west-east axis. The main original contribution to our understanding of the formation process of L1527 is the presentation of a simple 3D parameterisation based solely on regions that are not dominated by absorption. In the explored range (˜0.7 to 5 arcsec from the star) the model reproduces observations better than earlier attempts. The main results include: a measurement of the rotation velocity that confirms its evolution to Keplerian toward short distances; a measurement of the mean in-fall velocity, 0.43±0.10 km s-1, lower than free fall velocity, with no evidence for the significant r-dependence suggested by an earlier analysis; a measurement of the central mass, 0.23±0.06 M⊙ within a distance of 1.5 arcsec from the star, in agreement with earlier estimates obtained from a different range of distances; evidence for a strong disc plane depression of the in-falling flux resulting in an X shaped flow possibly caused by the freeze-out of CO molecules on dust grains; a measurement of the accretion rate, 3.5±1.0 10-7M⊙ yr-1at a distance of 1 arcsec (140 au) from the star; evidence for a 10° tilt of the symmetry plane of the envelope about the line of sight, cancelling below ˜3 arcsec from the star, but matching infrared observations and being also apparent on the sky map of the mean Doppler velocity.

  9. An ALMA view of the interstellar medium of the z = 4.77 lensed starburst SPT-S J213242-5802.9

    NASA Astrophysics Data System (ADS)

    Béthermin, M.; De Breuck, C.; Gullberg, B.; Aravena, M.; Bothwell, M. S.; Chapman, S. C.; Gonzalez, A. H.; Greve, T. R.; Litke, K.; Ma, J.; Malkan, M.; Marrone, D. P.; Murphy, E. J.; Spilker, J. S.; Stark, A. A.; Strandet, M.; Vieira, J. D.; Weiß, A.; Welikala, N.

    2016-02-01

    We present ALMA detections of the [NII] 205 μm and CO(12-11) emission lines, and the tentative detection of [CI] - for the strongly lensed (μ = 5.7 ± 0.5) dusty, star-forming galaxy SPT-S J213242-5802.9 (hereafter SPT2132-58) at z = 4.77. The [NII] and CO(12-11) lines are detected at 11.5 and 8.5σ levels, respectively, by our band 6 observations. The [CI] line is detected at 3.2σ after a reanalysis of existing band 3 data. The [CI] luminosity implies a gas mass of (3.8 ± 1.2) × 1010M⊙, and, consequently, a very short depletion timescale of 34 ± 13 Myr and a CO luminosity to gas mass conversion factor αCO of 1.0 ± 0.3 M⊙ (K km s-1 pc2)-1. SPT2132-58 is an extreme starburst with an intrinsic star formation rate of 1100 ± 200 M⊙/yr. We find a [CII]/[NII] ratio of 26 ± 6, which is the highest ratio reported at z > 4. This suggests that SPT2132-58 hosts an evolved interstellar medium (0.5 Z⊙< Z < 1.5 Z⊙), which may be dominated by photodissociation regions. The CO(2-1) and CO(5-4) transitions have lower CO to far-infrared ratios than local and high-redshift samples, while CO(12-11) is similar to these samples, suggesting the presence of an additional very excited component or an active galactic nucleus.

  10. Report on the Workshop Interstellar Medium and Star Formation with ALMA: Looking to the Future. A Workshop to Honour Tom Wilson held at Consejo Superior de Investigaciones Científicas, Madrid, Spain, 16-17 June 2008

    NASA Astrophysics Data System (ADS)

    Martin-Pintado, Jesus

    2008-12-01

    In June 2008, a group of friends and colleagues of Tom Wilson gathered in Madrid to honour his scientific career in a workshop on ALMA organised by three of his PhD students. The workshop was devoted to reviewing recent progress in our understanding of the main topics of research that Tom has pursued during his career: the physics and chemistry of the interstellar medium and how stars form. Specific topics included Hii regions, molecular clouds, clumps, cores, outflows and masers in Galactic and extragalactic environments, mainly from an observational perspective.

  11. High-Resolution Imaging in 3-mm and 0.8-mm Bands and Abundances of Shock/Dust Related Molecules Toward the Seyfert Galaxy NGC 1068 Observed with ALMA

    NASA Astrophysics Data System (ADS)

    Nakajima, T.; Takano, S.; Kohno, K.; Harada, N.; Herbst, E.; Tamura, Y.; Izumi, T.; Taniguchi, A.; Tosaki, T.

    2015-12-01

    We present the results of high-angular-resolution in 3-mm and 0.8-mm band observations with ALMA in cycle-0 toward one of the nearest galaxies with an active galactic nucleus (AGN), NGC 1068. The physical properties of CO isotopic species, CS, CN, and shock and dust related molecules such as HNCO, CH3CN, SO, and CH3OH were estimated using rotation diagrams. We discuss the chemistry of each species, and compare the fractional abundances in the circumnuclear disk (CND) and starburst ring with those of Galactic sources in order to study the overall characteristics.

  12. Advances In Cryogenic Monolithic Millimeter-wave Integrated Circuit (MMIC) Low Noise Amplifiers For CO Intensity Mapping and ALMA Band 2

    NASA Astrophysics Data System (ADS)

    Samoska, Lorene; Cleary, Kieran; Church, Sarah E.; Cuadrado-Calle, David; Fung, Andy; gaier, todd; gawande, rohit; Kangaslahti, Pekka; Lai, Richard; Lawrence, Charles R.; Readhead, Anthony C. S.; Sarkozy, Stephen; Seiffert, Michael D.; Sieth, Matthew

    2016-01-01

    We will present results of the latest InP HEMT MMIC low noise amplifiers in the 30-300 GHz range, with emphasis on LNAs and mixers developed for CO intensity mapping in the 40-80 GHz range, as well as MMIC LNAs suitable for ALMA Band 2 (67-90 GHz). The LNAs have been developed together with NGC in a 35 nm InP HEMT MMIC process. Recent results and a summary of best InP low noise amplifier data will be presented. This work describes technologies related to the detection and study of highly redshifted spectral lines from the CO molecule, a key tracer for molecular hydrogen. One of the most promising techniques for observing the Cosmic Dawn is intensity mapping of spectral-spatial fluctuations of line emission from neutral hydrogen (H I), CO, and [C II]. The essential idea is that instead of trying to detect line emission from individual galaxies, one measures the total line emission from a number of galaxies within the volume defined by a spectral-spatial pixel. Fluctuations from pixel to pixel trace large scale structure, and the evolution with redshift is revealed as a function of receiver frequency. A special feature of CO is the existence of multiple lines with a well-defined frequency relationship from the rotational ladder, which allows the possibility of cleanly separating the signal from other lines or foreground structure at other redshifts. Making use of this feature (not available to either HI or [C II] measurements) requires observing multiple frequencies, including the range 40-80 GHz, much of which is inaccessible from the ground or balloons.Specifically, the J=1->0 transition frequency is 115 GHz; J=2->1 is 230 GHz; J=3->2 is 345 GHz, etc. At redshift 7, these lines would appear at 14.4, 28.8, and 43.2 GHz, accessible from the ground. Over a wider range of redshifts, from 3 to 7, these lines would appear at frequencies from 14 to 86 GHz. A ground-based CO Intensity mapping experiment, COMAP, will utilize InP-based HEMT MMIC amplifier front ends in the

  13. Brown dwarf disks with ALMA

    SciTech Connect

    Ricci, L.; Isella, A.; Testi, L.; De Gregorio-Monsalvo, I.; Natta, A.; Scholz, A.

    2014-08-10

    We present Atacama Large Millimeter/submillimeter Array continuum and spectral line data at 0.89 mm and 3.2 mm for three disks surrounding young brown dwarfs and very low mass stars in the Taurus star forming region. Dust thermal emission is detected and spatially resolved for all the three disks, while CO(J = 3-2) emission is seen in two disks. We analyze the continuum visibilities and constrain the disks' physical structure in dust. The results of our analysis show that the disks are relatively large; the smallest one has an outer radius of about 70 AU. The inferred disk radii, radial profiles of the dust surface density, and disk to central object mass ratios lie within the ranges found for disks around more massive young stars. We derive from our observations the wavelength dependence of the millimeter dust opacity. In all the three disks, data are consistent with the presence of grains with at least millimeter sizes, as also found for disks around young stars, and confirm that the early stages of the solid growth toward planetesimals occur also around very low-mass objects. We discuss the implications of our findings on models of solids evolution in protoplanetary disks, the main mechanisms proposed for the formation of brown dwarfs and very low-mass stars, as well as the potential of finding rocky and giant planets around very low-mass objects.

  14. Exploring the molecular chemistry and excitation in obscured luminous infrared galaxies. An ALMA mm-wave spectral scan of NGC 4418

    NASA Astrophysics Data System (ADS)

    Costagliola, F.; Sakamoto, K.; Muller, S.; Martín, S.; Aalto, S.; Harada, N.; van der Werf, P.; Viti, S.; Garcia-Burillo, S.; Spaans, M.

    2015-10-01

    Context. Extragalactic observations allow the study of molecular chemistry and excitation under physical conditions which may differ greatly from those found in the Milky Way. The compact, obscured nuclei (CON) of luminous infrared galaxies (LIRG) combine large molecular columns with intense infrared (IR), ultra-violet (UV), and X- radiation and represent ideal laboratories for the study of the chemistry of the interstellar medium (ISM) under extreme conditions. Aims: Our aim was to obtain for the first time a multi-band spectral scan of a LIRG, and to derive molecular abundances and excitation to be compared to other Galactic and extragalactic environments. Methods: We obtained an ALMA Cycle 0 spectral scan of the dusty LIRG NGC 4418, spanning a total of 70.7 GHz in bands 3, 6, and 7. We use a combined local thermal equilibrium (LTE) and non-LTE (NLTE) fit of the spectrum in order to identify the molecular species and to derive column densities and excitation temperatures. We derive molecular abundances and compare them with other Galactic and extragalactic sources by means of a principal component analysis. Results: We detect 317 emission lines from a total of 45 molecular species, including 15 isotopic substitutions and 6 vibrationally excited variants. Our LTE/NLTE fit find kinetic temperatures from 20 to 350 K, and densities between 105 and 107 cm-3. The spectrum is dominated by vibrationally excited HC3N, HCN, and HNC, with vibrational temperatures from 300 to 450 K. We find that the chemistry of NCG 4418 is characterized by high abundances of HC3N, SiO, H2S, and c-HCCCH but a low CH3OH abundance. A principal component analysis shows that NGC 4418 and Arp 220 share very similar molecular abundances and excitation, which clearly set them apart from other Galactic and extragalactic environments. Conclusions: Our spectral scan confirms that the chemical complexity in the nucleus of NGC 4418 is one of the highest ever observed outside our Galaxy. The similar

  15. Filamentary structure and Keplerian rotation in the high-mass star-forming region G35.03+0.35 imaged with ALMA

    NASA Astrophysics Data System (ADS)

    Beltrán, M. T.; Sánchez-Monge, Á.; Cesaroni, R.; Kumar, M. S. N.; Galli, D.; Walmsley, C. M.; Etoka, S.; Furuya, R. S.; Moscadelli, L.; Stanke, T.; van der Tak, F. F. S.; Vig, S.; Wang, K.-S.; Zinnecker, H.; Elia, D.; Schisano, E.

    2014-11-01

    Context. Theoretical scenarios propose that high-mass stars are formed by disk-mediated accretion. Aims: To test the theoretical predictions on the formation of massive stars, we wish to make a thorough study at high-angular resolution of the structure and kinematics of the dust and gas emission toward the high-mass star-forming region G35.03+0.35, which harbors a disk candidate around a B-type (proto)star. Methods: We carried out ALMA Cycle 0 observations at 870 μm of dust of typical high-density, molecular outflow, and cloud tracers with resolutions of < 0''&dotbelow;5. Complementary Subaru COMICS 25 μm observations were carried out to trace the mid-infrared emission toward this star-forming region. Results: The submillimeter continuum emission has revealed a filamentary structure fragmented into six cores, called A-F. The filament could be in quasi-equilibrium taking into account that the mass per unit length of the filament, 200-375 M⊙/pc, is similar to the critical mass of a thermally and turbulently supported infinite cylinder, ~335 M⊙/pc. The cores, which are on average separated by ~0.02 pc, have deconvolved sizes of 1300-3400 AU, temperatures of 35-240 K, H2 densities >107 cm -3, and masses in the range 1-5 M⊙, and they are subcritical. Core A, which is associated with a hypercompact Hii region and could be the driving source of the molecular outflow observed in the region, is the most chemically rich source in G35.03+0.35 with strong emission of typical hot core tracers such as CH3CN. Tracers of high density and excitation show a clear velocity gradient along the major axis of the core, which is consistent with a disk rotating about the axis of the associated outflow. The PV plots along the SE-NW direction of the velocity gradient show clear signatures of Keplerian rotation, although infall could also be present, and they are consistent with the pattern of an edge-on Keplerian disk rotating about a star with a mass in the range 5-13 M⊙. The high

  16. Sub-kiloparsec ALMA Imaging of Compact Star-forming Galaxies at z ~ 2.5: Revealing the Formation of Dense Galactic Cores in the Progenitors of Compact Quiescent Galaxies

    NASA Astrophysics Data System (ADS)

    Barro, G.; Kriek, M.; Pérez-González, P. G.; Trump, J. R.; Koo, D. C.; Faber, S. M.; Dekel, A.; Primack, J. R.; Guo, Y.; Kocevski, D. D.; Muñoz-Mateos, J. C.; Rujoparkarn, W.; Seth, K.

    2016-08-01

    We present spatially resolved Atacama Large Millimeter/submillimeter Array (ALMA) 870 μm dust continuum maps of six massive, compact, dusty star-forming galaxies at z ˜ 2.5. These galaxies are selected for their small rest-frame optical sizes ({r}{{e,F160W}}˜ 1.6 kpc) and high stellar mass densities that suggest that they are direct progenitors of compact quiescent galaxies at z ˜ 2. The deep observations yield high far-infrared (FIR) luminosities of {L}{{IR}}={10}12.3-12.8 {L}ȯ and star formation rates (SFRs) of SFR = 200–700 M ⊙ yr‑1, consistent with those of typical star-forming “main sequence” galaxies. The high spatial resolution (FWHM ˜ 0.″12–0.″18) ALMA and Hubble Space Telescope photometry are combined to construct deconvolved, mean radial profiles of their stellar mass and (UV+IR) SFR. We find that the dusty, nuclear IR–SFR overwhelmingly dominates the bolometric SFR up to r ˜ 5 kpc, by a factor of over 100× from the unobscured UV–SFR. Furthermore, the effective radius of the mean SFR profile ({r}{{e,SFR}}˜ 1 kpc) is ˜30% smaller than that of the stellar mass profile. The implied structural evolution, if such nuclear starburst last for the estimated gas depletion time of Δt = ±100 Myr, is a 4× increase of the stellar mass density within the central 1 kpc and a 1.6× decrease of the half-mass–radius. This structural evolution fully supports dissipation-driven, formation scenarios in which strong nuclear starbursts transform larger, star-forming progenitors into compact quiescent galaxies.

  17. Sub-kiloparsec ALMA Imaging of Compact Star-forming Galaxies at z ~ 2.5: Revealing the Formation of Dense Galactic Cores in the Progenitors of Compact Quiescent Galaxies

    NASA Astrophysics Data System (ADS)

    Barro, G.; Kriek, M.; Pérez-González, P. G.; Trump, J. R.; Koo, D. C.; Faber, S. M.; Dekel, A.; Primack, J. R.; Guo, Y.; Kocevski, D. D.; Muñoz-Mateos, J. C.; Rujopakarn, W.; Seth, K.

    2016-08-01

    We present spatially resolved Atacama Large Millimeter/submillimeter Array (ALMA) 870 μm dust continuum maps of six massive, compact, dusty star-forming galaxies at z ˜ 2.5. These galaxies are selected for their small rest-frame optical sizes ({r}{{e,F160W}}˜ 1.6 kpc) and high stellar mass densities that suggest that they are direct progenitors of compact quiescent galaxies at z ˜ 2. The deep observations yield high far-infrared (FIR) luminosities of {L}{{IR}}={10}12.3-12.8 {L}⊙ and star formation rates (SFRs) of SFR = 200-700 M ⊙ yr-1, consistent with those of typical star-forming “main sequence” galaxies. The high spatial resolution (FWHM ˜ 0.″12-0.″18) ALMA and Hubble Space Telescope photometry are combined to construct deconvolved, mean radial profiles of their stellar mass and (UV+IR) SFR. We find that the dusty, nuclear IR-SFR overwhelmingly dominates the bolometric SFR up to r ˜ 5 kpc, by a factor of over 100× from the unobscured UV-SFR. Furthermore, the effective radius of the mean SFR profile ({r}{{e,SFR}}˜ 1 kpc) is ˜30% smaller than that of the stellar mass profile. The implied structural evolution, if such nuclear starburst last for the estimated gas depletion time of Δt = ±100 Myr, is a 4× increase of the stellar mass density within the central 1 kpc and a 1.6× decrease of the half-mass-radius. This structural evolution fully supports dissipation-driven, formation scenarios in which strong nuclear starbursts transform larger, star-forming progenitors into compact quiescent galaxies.

  18. ALMA imaging of gas and dust in a galaxy protocluster at redshift 5.3: [C II] emission in 'typical' galaxies and dusty starbursts ≈1 billion years after the big bang

    SciTech Connect

    Riechers, Dominik A.; Carilli, Christopher L.; Capak, Peter L.; Yan, Lin; Scoville, Nicholas Z.; Smolčić, Vernesa; Schinnerer, Eva; Yun, Min; Cox, Pierre; Bertoldi, Frank; Karim, Alexander

    2014-12-01

    We report interferometric imaging of [C II]({sup 2} P {sub 3/2}→{sup 2} P {sub 1/2}) and OH({sup 2}Π{sub 1/2} J = 3/2→1/2) emission toward the center of the galaxy protocluster associated with the z = 5.3 submillimeter galaxy (SMG) AzTEC-3, using the Atacama Large (sub)Millimeter Array (ALMA). We detect strong [C II], OH, and rest-frame 157.7 μm continuum emission toward the SMG. The [C II]({sup 2} P {sub 3/2}→{sup 2} P {sub 1/2}) emission is distributed over a scale of 3.9 kpc, implying a dynamical mass of 9.7 × 10{sup 10} M {sub ☉}, and a star formation rate (SFR) surface density of Σ{sub SFR} = 530 M {sub ☉} yr{sup –1} kpc{sup –2}. This suggests that AzTEC-3 forms stars at Σ{sub SFR} approaching the Eddington limit for radiation pressure supported disks. We find that the OH emission is slightly blueshifted relative to the [C II] line, which may indicate a molecular outflow associated with the peak phase of the starburst. We also detect and dynamically resolve [C II]({sup 2} P {sub 3/2}→{sup 2} P {sub 1/2}) emission over a scale of 7.5 kpc toward a triplet of Lyman-break galaxies with moderate UV-based SFRs in the protocluster at ∼95 kpc projected distance from the SMG. These galaxies are not detected in the continuum, suggesting far-infrared SFRs of <18-54 M {sub ☉} yr{sup –1}, consistent with a UV-based estimate of 22 M {sub ☉} yr{sup –1}. The spectral energy distribution of these galaxies is inconsistent with nearby spiral and starburst galaxies, but resembles those of dwarf galaxies. This is consistent with expectations for young starbursts without significant older stellar populations. This suggests that these galaxies are significantly metal-enriched, but not heavily dust-obscured, 'normal' star-forming galaxies at z > 5, showing that ALMA can detect the interstellar medium in 'typical' galaxies in the very early universe.

  19. Amigas Latinas Motivando el ALMA (ALMA): Development and Pilot Implementation of a Stress Reduction Promotora Intervention

    PubMed Central

    Green, Melissa A.; Perez, Georgina; Ornelas, India J.; Tran, Anh N.; Blumenthal, Connie; Lyn, Michelle; Corbie-Smith, Giselle

    2014-01-01

    Use of mental health care services for psychological distress is limited among Latino immigrants. In geographic areas where migration has been rapid, mental health systems possess limited capacity to provide bilingual and bicultural assistance. The development of a bilingual and bicultural workforce is a necessary yet long-term solution. More immediate strategies, however, are needed to meet the needs of immigrant Latinos. This paper describes the development of a stress-reduction focused, lay health advisor training that targets individual behavior change among Latina immigrants. The theoretical foundation, curriculum components, and pilot implementation of the training are discussed. As natural leaders, Latina promotoras disseminated learned strategies and resources within their communities. The lay health advisor model is a salient method for disseminating information regarding mental health and stress reduction among Latinas. PMID:25364312

  20. Amigas Latinas Motivando el ALMA (ALMA): Development and Pilot Implementation of a Stress Reduction Promotora Intervention.

    PubMed

    Green, Melissa A; Perez, Georgina; Ornelas, India J; Tran, Anh N; Blumenthal, Connie; Lyn, Michelle; Corbie-Smith, Giselle

    2012-08-01

    Use of mental health care services for psychological distress is limited among Latino immigrants. In geographic areas where migration has been rapid, mental health systems possess limited capacity to provide bilingual and bicultural assistance. The development of a bilingual and bicultural workforce is a necessary yet long-term solution. More immediate strategies, however, are needed to meet the needs of immigrant Latinos. This paper describes the development of a stress-reduction focused, lay health advisor training that targets individual behavior change among Latina immigrants. The theoretical foundation, curriculum components, and pilot implementation of the training are discussed. As natural leaders, Latina promotoras disseminated learned strategies and resources within their communities. The lay health advisor model is a salient method for disseminating information regarding mental health and stress reduction among Latinas.

  1. [Genetic characterisation of Powassan virus (POWV) isolated from Haemophysalis longicornis ticks in Primorye and two strains of Tick-borne encephalitis virus (TBEV) (Flaviviridae, Flavivirus): Alma-Arasan virus (AAV) isolated from Ixodes persulcatus ticks in Kazakhstan and Malyshevo virus isolated from Aedes vexans nipponii mosquitoes in Khabarovsk kray].

    PubMed

    L'vov, D K; Al'khovskiĭ, S V; Shchelkanov, M Iu; Deriabin, P G; Gitel'man, A K; Botikov, A G; Aristova, V A

    2014-01-01

    The complete genomes of the three tick-borne flaviviruses (genus Flavivirus, fam. Bunyaviridae) were sequenced: Povassan virus (POWV, strain LEIV-3070Prm, isolated from Haemophysalis logicornis in Primorsky Krai, Russia in 1977), Alma-Arasan virus (AAV, strain LEIV-1380Kaz, isolated from Ixodes persulcatus ticks in Kazakhstan in 1977) and Malyshevo virus (isolated from a pool of Aedes vexans nipponii mosquitoes, in the Khabarovsk Krai, Russia in 1978). It is shown that AAV and Malyshevo virus are the strains of Tick-borne encephalitis virus (TBEV) and belong to Sibirian and Far-Eastern genotypes, respectively (GenBank ID: AAV KJ744033; strain Malyshevo KJ744034). Phylogenetically AAV is closest related (94,6% nt and 98,3% aa identity) to TBEV strains, isolated in Sibiria (Vasilchenko, Aino, Chita-653, Irkutsk-12). Malyshevo virus is closest related (96,4% nt and 98,3% nt identity) to strains of TBEV, isolated in Far Eastern part of Russia (1230, Spassk-72, Primorye-89). POWV LEIV-3070Prm has 99.7% identity with the prototype strain POWV LB, isolated in Canada and 99.5% of isolates with Far-Eastern strains of POWV (Spassk-9 and Nadezdinsk-1991).

  2. Teacher History: Student Historians, Faculty Biographies, and the "Alma Mater"

    ERIC Educational Resources Information Center

    Stofferahn, Steven A.

    2009-01-01

    When his department chair asked him a few years ago to take over as faculty advisor to their university's chapter of the Phi Alpha Theta history honor society, the author readily accepted. Not only would it provide a great opportunity to get to know some of their best students better, it would also help a junior faculty member like himself fulfill…

  3. The Marriage of Alma Mater to Adam Smith.

    ERIC Educational Resources Information Center

    Buescher, John B.

    1987-01-01

    Businesses and universities must be encouraged to act from their traditional positions of strength, based on the longest view and the broadest interests. They must examine carefully their potential sources of conflict as well as opportunities for benefit before engaging in alliances that may become complex and difficult to manage. (MSE)

  4. TRANSITION DISK CHEMISTRY AND FUTURE PROSPECTS WITH ALMA

    SciTech Connect

    Cleeves, L. Ilsedore; Bergin, Edwin A.; Bethell, Thomas J.; Calvet, Nuria; Fogel, Jeffrey K. J.; Sauter, Juergen; Wolf, Sebastian

    2011-12-10

    We explore the chemical structure of a disk that contains a large central gap of R {approx} 45 AU, as is commonly seen in transitional disk systems. In our chemical model of a disk with a cleared inner void, the midplane becomes revealed to the central star so that it is directly irradiated. The midplane material at the truncation radius is permissive to reprocessed optical heating radiation, but opaque to the photodissociating ultraviolet, creating an environment abundant in gas-phase molecules. Thus the disk midplane, which would otherwise for a full disk be dominated by near complete heavy element freeze-out, should become observable in molecular emission. If this prediction is correct this has exciting prospects for observations with the Atacama Large Millimeter/Submillimeter Array, as the inner transition region should thus be readily detected and resolved, especially using high-J rotational transitions excited in the high density midplane gas. Therefore, such observations will potentially provide us with a direct probe of the physics and chemistry at this actively evolving interface.

  5. Indigenous Digital Storytelling in Video: Witnessing with Alma Desjarlais

    ERIC Educational Resources Information Center

    Iseke, Judy M.

    2011-01-01

    Indigenous digital storytelling in video is a way of witnessing the stories of Indigenous communities and Elders, including what has happened and is happening in the lives and work of Indigenous peoples. Witnessing includes acts of remembrance in which we look back to reinterpret and recreate our relationship to the past in order to understand the…

  6. Saving Alma Mater: A Rescue Plan for America's Public Universities

    ERIC Educational Resources Information Center

    Garland, James C.

    2009-01-01

    America's public universities educate 80% of our nation's college students. But in the wake of rising demands on state treasuries, changing demographics, growing income inequality, and legislative indifference, many of these institutions have fallen into decline. Tuition costs have skyrocketed, class sizes have gone up, the number of courses…

  7. ALMA Multi-line Observations of the IR-bright Merger VV 114

    NASA Astrophysics Data System (ADS)

    Saito, Toshiki; Iono, Daisuke; Yun, Min S.; Ueda, Junko; Nakanishi, Kouichiro; Sugai, Hajime; Espada, Daniel; Imanishi, Masatoshi; Motohara, Kentaro; Hagiwara, Yosiaki; Tateuchi, Ken; Lee, Minju; Kawabe, Ryohei

    2015-04-01

    We present Atacama Large Millimeter/submillimeter Array cycle 0 observations of the molecular gas and dust in the IR-bright mid-stage merger VV 114 obtained at 160-800 pc resolution. The main aim of this study is to investigate the distribution and kinematics of the cold/warm gas and to quantify the spatial variation of the excitation conditions across the two merging disks. The data contain 10 molecular lines, including the first detection of extranuclear CH3OH emission in interacting galaxies, as well as continuum emission. We map the 12CO(3-2)/12CO(1-0) and the 12CO(1-0)/13CO(1-0) line ratio at 800 pc resolution (in the units of K km s-1), and find that these ratios vary from 0.2-0.8 and 5-50, respectively. Conversely, the 200 pc resolution HCN(4-3)/HCO+(4-3) line ratio shows low values (<0.5) at a filament across the disks except for the unresolved eastern nucleus which is three times higher (1.34 ± 0.09). We conclude from our observations and a radiative transfer analysis that the molecular gas in the VV 114 system consists of five components with different physical and chemical conditions, i.e., (1) dust-enshrouded nuclear starbursts and/or active galactic nuclei, (2) widespread star-forming dense gas, (3) merger-induced shocked gas, (4) quiescent tenuous gas arms without star formation, and (5) H2 gas mass of (3.8 ± 0.7) × 107 {{M}⊙ } (assuming a conversion factor of αCO = 0.8 {{M}⊙ } {{(K km {{s}-1} p{{c}2})}-1}) at the tip of the southern tidal arm, as a potential site of tidal dwarf galaxy formation.

  8. The nuclear gas disk of NGC 1566 dissected by SINFONI and ALMA

    NASA Astrophysics Data System (ADS)

    Smajić, S.; Moser, L.; Eckart, A.; Busch, G.; Combes, F.; García-Burillo, S.; Valencia-S., M.; Horrobin, M.

    2015-11-01

    We present the results of near-infrared (NIR) H- and K-band European Southern Observatory SINFONI integral field spectroscopy (IFS) of the Seyfert galaxy NGC 1566. We investigate the central kpc of this nearby galaxy, concentrating on excitation conditions, morphology, and stellar content. NGC 1566 was selected from our NUGA (-south) sample and is a ringed, spiral galaxy with a stellar bar in north-south direction (PA ~ 5°). The galaxy inhibits a very active Seyfert 1 nucleus but narrow line ratios from optical observations in the nuclear region are similar to Seyfert 2 galaxies. The recent strong activity phase, as inferred from strong variablity in X-ray to IR wavelengths, makes NGC 1566 an ideal candidate to look for feeding and feedback of a supermassive black hole. We present emission and absorption line measurements in the central kpc of NGC 1566. Broad and narrow Brγ lines were detected. The detection of a broad Brγ component is a clear sign of a supermassive black hole in the center. Blackbody emission temperatures of ~1000 K are indicative of a hot dust component, the torus, in the nuclear region. The molecular hydrogen lines, hydrogen recombination lines, and [Fe ii] indicate that the excitation at the center is coming from an AGN. The central region is predominantly inhabited by molecular gas, dust, and an old K-M type giant stellar population. The molecular gas and stellar velocity maps both show a rotation pattern. The molecular gas velocity field shows a perturbation toward the center that is typical for bars or spiral density waves. The molecular gas species of warm H2(1-0)S(1) and cold 12CO(3-2) gas trace a nuclear gas disk of about 3″ in radius with a nuclear spiral reaching toward the nucleus. From the equivalent width of H2(1-0)S(1) a molecular ring with r ≲ 3″ can be inferred. This spiral seems to be an instrument that allows gas to fall toward the nucleus down to <50 pc scales. The excitation of molecular hydrogen in the nuclear gas disk is not clear, but diagnostic diagrams show a distinction between the nuclear region and a <9 Myr old star-forming region at the southwestern spiral arm. Gas that might be shocked is detected ≈2″ from the center, which is visible in dispersion maps of H2(1-0)S(1) and 12CO(3-2) and in the 0.87 mm continuum. Based on the ESO-VLT proposal ID:090.B-0657(A).Appendix A is available in electronic form at http://www.aanda.org

  9. A CLUSTER IN THE MAKING: ALMA REVEALS THE INITIAL CONDITIONS FOR HIGH-MASS CLUSTER FORMATION

    SciTech Connect

    Rathborne, J. M.; Contreras, Y.; Longmore, S. N.; Bastian, N.; Jackson, J. M.; Alves, J. F.; Bally, J.; Foster, J. B.; Garay, G.; Kruijssen, J. M. D.; Testi, L.; Walsh, A. J.

    2015-04-01

    G0.253+0.016 is a molecular clump that appears to be on the verge of forming a high-mass cluster: its extremely low dust temperature, high mass, and high density, combined with its lack of prevalent star formation, make it an excellent candidate for an Arches-like cluster in a very early stage of formation. Here we present new Atacama Large Millimeter/Sub-millimeter Array observations of its small-scale (∼0.07 pc) 3 mm dust continuum and molecular line emission from 17 different species that probe a range of distinct physical and chemical conditions. The data reveal a complex network of emission features with a complicated velocity structure: there is emission on all spatial scales, the morphology of which ranges from small, compact regions to extended, filamentary structures that are seen in both emission and absorption. The dust column density is well traced by molecules with higher excitation energies and critical densities, consistent with a clump that has a denser interior. A statistical analysis supports the idea that turbulence shapes the observed gas structure within G0.253+0.016. We find a clear break in the turbulent power spectrum derived from the optically thin dust continuum emission at a spatial scale of ∼0.1 pc, which may correspond to the spatial scale at which gravity has overcome the thermal pressure. We suggest that G0.253+0.016 is on the verge of forming a cluster from hierarchical, filamentary structures that arise from a highly turbulent medium. Although the stellar distribution within high-mass Arches-like clusters is compact, centrally condensed, and smooth, the observed gas distribution within G0.253+0.016 is extended, with no high-mass central concentration, and has a complex, hierarchical structure. If this clump gives rise to a high-mass cluster and its stars are formed from this initially hierarchical gas structure, then the resulting cluster must evolve into a centrally condensed structure via a dynamical process.

  10. ALMA HINTS AT THE PRESENCE OF TWO COMPANIONS IN THE DISK AROUND HD 100546

    SciTech Connect

    Walsh, Catherine; Juhász, Attila; Pinilla, Paola; Harsono, Daniel; Mathews, Geoffrey S.; Hogerheijde, Michiel R.; Dent, William R. F.; Birnstiel, T.; Meeus, Gwendolyn; Nomura, Hideko; Aikawa, Yuri; Millar, T. J.; Sandell, Göran

    2014-08-10

    HD 100546 is a well-studied Herbig Be star-disk system that likely hosts a close-in companion with compelling observational evidence for an embedded protoplanet at 68 AU. We present Atacama Large Millimeter/Submillimeter Array observations of the HD 100546 disk which resolve the gas and dust structure at (sub)millimeter wavelengths. The CO emission (at 345.795 GHz) originates from an extensive molecular disk (390 ± 20 AU in radius) whereas the continuum emission is more compact (230 ± 20 AU in radius), suggesting radial drift of the millimeter-sized grains. The CO emission is similar in extent to scattered light images indicating well-mixed gas and micrometer-sized grains in the disk atmosphere. Assuming azimuthal symmetry, a single-component power-law model cannot reproduce the continuum visibilities. The visibilities and images are better reproduced by a double-component model: a compact ring with a width of 21 AU centered at 26 AU and an outer ring with a width of 75 ± 3 AU centered at 190 ± 3 AU. The influence of a companion and protoplanet on the dust evolution is investigated. The companion at 10 AU facilitates the accumulation of millimeter-sized grains within a compact ring, ≈20-30 AU, by ≈10 Myr. The injection of a protoplanet at 1 Myr hastens the ring formation (≈1.2 Myr) and also triggers the development of an outer ring (≈100-200 AU). These observations provide additional evidence for the presence of a close-in companion and hint at dynamical clearing by a protoplanet in the outer disk.

  11. ALMA Observations of the Debris Disk of Solar Analog τ Ceti

    NASA Astrophysics Data System (ADS)

    MacGregor, Meredith A.; Lawler, Samantha M.; Wilner, David J.; Matthews, Brenda C.; Kennedy, Grant M.; Booth, Mark; Di Francesco, James

    2016-09-01

    We present 1.3 mm observations of the Sun-like star τ Ceti with the Atacama Large Millimeter/submillimeter Array that probe angular scales of ∼ 1\\prime\\prime (4 au). This first interferometric image of the τ Ceti system, which hosts both a debris disk and a possible multiplanet system, shows emission from a nearly face-on belt of cold dust with a position angle of 90^\\circ surrounding an unresolved central source at the stellar position. To characterize this emission structure, we fit parametric models to the millimeter visibilities. The resulting best-fit model yields an inner belt edge of {6.2}-4.6+9.8 au, consistent with inferences from lower resolution, far-infrared Herschel observations. While the limited data at sufficiently short baselines preclude us from placing stronger constraints on the belt properties and its relation to the proposed five planet system, the observations do provide a strong lower limit on the fractional width of the belt, {{Δ }}R/R\\gt 0.75 with 99% confidence. This fractional width is more similar to broad disks such as HD 107146 than narrow belts such as the Kuiper Belt and Fomalhaut. The unresolved central source has a higher flux density than the predicted flux of the stellar photosphere at 1.3 mm. Given previous measurements of an excess by a factor of ∼2 at 8.7 mm, this emission is likely due to a hot stellar chromosphere.

  12. ALMA MEASUREMENTS OF THE HNC AND HC{sub 3}N DISTRIBUTIONS IN TITAN'S ATMOSPHERE

    SciTech Connect

    Cordiner, M. A.; Nixon, C. A.; Serigano, J.; Charnley, S. B.; Milam, S. N.; Mumma, M. J.; Villanueva, G.; Paganini, L.; Teanby, N. A.; Irwin, P. G. J.; Lis, D. C.; Kuan, Y.-J.; Remijan, A. J.

    2014-11-10

    We present spectrally and spatially resolved maps of HNC and HC{sub 3}N emission from Titan's atmosphere, obtained using the Atacama Large Millimeter/submillimeter Array on 2013 November 17. These maps show anisotropic spatial distributions for both molecules, with resolved emission peaks in Titan's northern and southern hemispheres. The HC{sub 3}N maps indicate enhanced concentrations of this molecule over the poles, consistent with previous studies of Titan's photochemistry and atmospheric circulation. Differences between the spectrally integrated flux distributions of HNC and HC{sub 3}N show that these species are not co-spatial. The observed spectral line shapes are consistent with HNC being concentrated predominantly in the mesosphere and above (at altitudes z ≳ 400 km), whereas HC{sub 3}N is abundant at a broader range of altitudes (z ≈ 70-600 km). From spatial variations in the HC{sub 3}N line profile, the locations of the HC{sub 3}N emission peaks are shown to be variable as a function of altitude. The peaks in the integrated emission from HNC and the line core (upper atmosphere) component of HC{sub 3}N (at z ≳ 300 km) are found to be asymmetric with respect to Titan's polar axis, indicating that the mesosphere may be more longitudinally variable than previously thought. The spatially integrated HNC and HC{sub 3}N spectra are modeled using the NEMESIS planetary atmosphere code and the resulting best-fitting disk-averaged vertical mixing ratio profiles are found to be in reasonable agreement with previous measurements for these species. Vertical column densities of the best-fitting gradient models for HNC and HC{sub 3}N are 1.9 × 10{sup 13} cm{sup –2} and 2.3 × 10{sup 14} cm{sup –2}, respectively.

  13. ALMA reveals sunburn: CO dissociation around AGB stars in the globular cluster 47 Tucanae

    NASA Astrophysics Data System (ADS)

    McDonald, I.; Zijlstra, A. A.; Lagadec, E.; Sloan, G. C.; Boyer, M. L.; Matsuura, M.; Smith, R. J.; Smith, C. L.; Yates, J. A.; van Loon, J. Th.; Jones, O. C.; Ramstedt, S.; Avison, A.; Justtanont, K.; Olofsson, H.; Blommaert, J. A. D. L.; Goldman, S. R.; Groenewegen, M. A. T.

    2015-11-01

    Atacama Large Millimetre Array observations show a non-detection of carbon monoxide around the four most luminous asymptotic giant branch (AGB) stars in the globular cluster 47 Tucanae. Stellar evolution models and star counts show that the mass-loss rates from these stars should be ˜1.2-3.5 × 10-7 M⊙ yr-1. We would naïvely expect such stars to be detectable at this distance (4.5 kpc). By modelling the ultraviolet radiation field from post-AGB stars and white dwarfs in 47 Tuc, we conclude that CO should be dissociated abnormally close to the stars. We estimate that the CO envelopes will be truncated at a few hundred stellar radii from their host stars and that the line intensities are about two orders of magnitude below our current detection limits. The truncation of CO envelopes should be important for AGB stars in dense clusters. Observing the CO (3-2) and higher transitions and targeting stars far from the centres of clusters should result in the detections needed to measure the outflow velocities from these stars.

  14. EXTREME DUST DISKS IN Arp 220 AS REVEALED BY ALMA

    SciTech Connect

    Wilson, C. D.; Rangwala, N.; Glenn, J.; Maloney, P. R.; Spinoglio, L.; Pereira-Santaella, M.

    2014-07-10

    We present new images of Arp 220 from the Atacama Large Millimeter/submillimeter Array with the highest combination of frequency (691 GHz) and resolution (0.''36 × 0.''20) ever obtained for this prototypical ultraluminous infrared galaxy. The western nucleus is revealed to contain warm (200 K) dust that is optically thick (τ{sub 434} {sub μm} = 5.3), while the eastern nucleus is cooler (80 K) and somewhat less opaque (τ{sub 434} {sub μm} = 1.7). We derive full width at half-maximum diameters of 76 × ≤ 70 pc and 123 × 79 pc for the western and eastern nucleus, respectively. The two nuclei combined account for (83{sub −38}{sup +65} (calibration) {sub −34}{sup +0} (systematic))% of the total infrared luminosity of Arp 220. The luminosity surface density of the western nucleus (log (σT{sup 4})=14.3±0.2{sub −0.7}{sup +0} in units of L {sub ☉} kpc{sup –2}) appears sufficiently high to require the presence of an active galactic nucleus (AGN) or a ''hot starburst'', although the exact value depends sensitively on the brightness distribution adopted for the source. Although the role of any central AGN remains open, the inferred mean gas column densities of (0.6-1.8) × 10{sup 25} cm{sup –2} mean that any AGN in Arp 220 must be Compton-thick.

  15. ALMA observations of the Antennae galaxies. I. A new window on a prototypical merger

    SciTech Connect

    Whitmore, Bradley C.; Brogan, Crystal; Evans, Aaron; Hibbard, John; Leroy, Adam; Remijan, Anthony; Sheth, Kartik; Chandar, Rupali; Johnson, Kelsey; Privon, George

    2014-11-10

    We present the highest spatial resolution (≈0.''5) CO (3-2) observations to date of the 'overlap' region in the merging Antennae galaxies (NGC 4038/39), taken with the Atacama Large Millimeter/submillimeter Array. We report on the discovery of a long (3 kpc), thin (aspect ratio 30/1), filament of CO gas that breaks up into roughly 10 individual knots. Each individual knot has a low internal velocity dispersion (≈10 km s{sup –1}); the dispersion of the ensemble of knots in the filament is also low (≈10 km s{sup –1}). At the other extreme, we find that the individual clouds in the supergiant molecular cloud 2 region discussed by Wilson and collaborators have a large range of internal velocity dispersions (10 to 80 km s{sup –1}), and a large dispersion among the ensemble (≈80 km s{sup –1}). Other large-scale features observed in CO emission, and their correspondence with historical counterparts using observations in other wavelengths, are also discussed. We compare the locations of small-scale CO features with a variety of multi-wavelength observations, in particular broad- (BVIJH) and narrow-band data (H{sub α} and Pa{sub β}) taken with the Hubble Space Telescope, and radio (3.6 cm) continuum observations taken with the Karl G. Jansky Very Large Array. This comparison leads to the development of an evolutionary classification system that provides a framework for studying the sequence of star cluster formation and evolution—from diffuse supergiant molecular clouds (SGMCs) to proto, embedded, emerging, young, intermediate/old clusters. The relative timescales have been assessed by determining the fractional population of sources at each evolutionary stage. The main uncertainty in this estimate is the identification of four regions as candidate protoclusters (i.e., strong compact CO emission but no clearly associated radio emission). Using the evolutionary framework, we estimate that the maximum age range of clusters in a single GMC is ≈10 Myr, which suggests that the molecular gas is removed over this timescale, resulting in the cessation of star formation and the destruction of the GMC within a radius of about 200 pc.

  16. Is the Alma Ata vision of comprehensive primary health care viable? Findings from an international project

    PubMed Central

    Labonté, Ronald; Sanders, David; Packer, Corinne; Schaay, Nikki

    2014-01-01

    Background The 4-year (2007–2011) Revitalizing Health for All international research program (http://www.globalhealthequity.ca/projects/proj_revitalizing/index.shtml) supported 20 research teams located in 15 low- and middle-income countries to explore the strengths and weaknesses of comprehensive primary health care (CPHC) initiatives at their local or national levels. Teams were organized in a triad comprised of a senior researcher, a new researcher, and a ‘research user’ from government, health services, or other organizations with the authority or capacity to apply the research findings. Multiple regional and global team capacity-enhancement meetings were organized to refine methods and to discuss and assess cross-case findings. Objective Most research projects used mixed methods, incorporating analyses of qualitative data (interviews and focus groups), secondary data, and key policy and program documents. Some incorporated historical case study analyses, and a few undertook new surveys. The synthesis of findings in this report was derived through qualitative analysis of final project reports undertaken by three different reviewers. Results Evidence of comprehensiveness (defined in this research program as efforts to improve equity in access, community empowerment and participation, social and environmental health determinants, and intersectoral action) was found in many of the cases. Conclusions Despite the important contextual differences amongst the different country studies, the similarity of many of their findings, often generated using mixed methods, attests to certain transferable health systems characteristics to create and sustain CPHC practices. These include:  Well-trained and supported community health workers (CHWs) able to work effectively with marginalized communities Effective mechanisms for community participation, both informal (through participation in projects and programs, and meaningful consultation) and formal (though program management structures) Co-partnership models in program and policy development (in which financial and knowledge supports from governments or institutions are provided to communities, which retain decision-making powers in program design and implementation) Support for community advocacy and engagement in health and social systems decision making These characteristics, in turn, require a political context that supports state responsibilities for redistributive health and social protection measures. PMID:25150030

  17. Si-BEARING MOLECULES TOWARD IRC+10216: ALMA UNVEILS THE MOLECULAR ENVELOPE OF CWLeo

    SciTech Connect

    Prieto, L. Velilla; Cernicharo, J.; Quintana-Lacaci, G.; Agúndez, M.; Fonfría, J. P.; Marcelino, N.; Zúñiga, J.; Requena, A.; Bastida, A.; Lique, F.

    2015-06-01

    We report the detection of SiS rotational lines in high-vibrational states as well as SiO and SiC{sub 2} lines in their ground vibrational state toward IRC+10216 during the Atacama Large Millimeter Array Cycle 0. The spatial distribution of these molecules shows compact emission for SiS and a more extended emission for SiO and SiC{sub 2} and also proves the existence of an increase in the SiC{sub 2} emission at the outer shells of the circumstellar envelope (CSE). We analyze the excitation conditions of the vibrationally excited SiS using the population diagram technique, and we use a large velocity gradient model to compare with the observations. We found moderate discrepancies between the observations and the models that could be explained if SiS lines detected are optically thick. Additionally, the line profiles of the detected rotational lines in the high-energy vibrational states show a decreasing linewidth with increasing energy levels. This may be evidence that these lines could be excited only in the inner shells, i.e., the densest and hottest, of the CSE of IRC+10216.

  18. Report on a Brainstorming Meeting about the "ALMA Interdisciplinary Teaching Project"

    NASA Astrophysics Data System (ADS)

    Boffin, H.; West, R.

    2004-09-01

    RECENT large-scale surveys have documented a widespread lack of interest in science and technology among Europe's young people. This development is highly worrying as it may lead to a lack of qualified scientists and teachers and may ultimately have dramatic demographic consequences on this continent. Various reasons for this situation have been identified and it is generally acknowledged that teaching quality at the primary and secondary levels plays a crucial role in this context. Means and methods to remedy this undesirable situation are being looked into in many countries and the European Commission has issued a strong plea for the creation of new educational initiatives, in particular broad and general ones that are easily adaptable to national curricula.

  19. Hail to Thee, Our Alma Mater: Alumni Role Identity and the Relationship to Institutional Support Behaviors

    ERIC Educational Resources Information Center

    McDearmon, J. Travis

    2013-01-01

    With the decline in state and federal support for higher education continuing to plague colleges and universities across the U.S., many institutions are looking to increase the levels of support annually received from alumni and other constituencies. Research on alumni relations in American colleges and universities has historically focused on…

  20. ALMA observations of a candidate molecular outflow in an obscured quasar

    SciTech Connect

    Sun, Ai-Lei; Greene, Jenny E.; Zakamska, Nadia L.; Nesvadba, Nicole P. H.

    2014-08-01

    We present Atacama Large Millimeter/Submillimeter Array CO (1-0) and CO (3-2) observations of SDSS J135646.10+102609.0, an obscured quasar and ultra-luminous infrared galaxy with two merging nuclei and a known 20 kpc scale ionized outflow. The total molecular gas mass is M{sub mol}≈9{sub −6}{sup +19}×10{sup 8} M{sub ☉}, mostly distributed in a compact rotating disk at the primary nucleus (M{sub mol} ≈ 3 × 10{sup 8} M{sub ☉}) and an extended tidal arm (M{sub mol} ≈ 5 × 10{sup 8} M{sub ☉}). The tidal arm is one of the most massive molecular tidal features known; we suggest that it is due to the lower chance of shock dissociation in this elliptical/disk galaxy merger. In the spatially resolved CO (3-2) data, we find a compact (r ≈ 0.3 kpc) high-velocity (v ≈ 500 km s{sup –1}) redshifted feature in addition to the rotation at the N nucleus. We propose a molecular outflow as the most likely explanation for the high-velocity gas. The outflowing mass of M{sub mol} ≈ 7 × 10{sup 7} M{sub ☉} and the short dynamical time of t{sub dyn} ≈ 0.6 Myr yield a very high outflow rate of M-dot{sub mol}≈350 M{sub ☉} yr{sup –1} and can deplete the gas in a million years. We find a low star formation rate (<16 M{sub ☉} yr{sup –1} from the molecular content and <21 M{sub ☉} yr{sup –1} from the far-infrared spectral energy distribution decomposition) that is inadequate to supply the kinetic luminosity of the outflow ( E-dot ≈3×10{sup 43} erg s{sup –1}). Therefore, the active galactic nucleus (AGN), with a bolometric luminosity of 10{sup 46} erg s{sup –1}, likely powers the outflow. The momentum boost rate of the outflow ( p-dot /(L{sub bol}/c)≈3) is lower than typical molecular outflows associated with AGNs, which may be related to its compactness. The molecular and ionized outflows are likely two distinct bursts induced by episodic AGN activity which varies on a timescale of 10{sup 7} yr.

  1. SI-BEARING MOLECULES TOWARD IRC+10216: ALMA UNVEILS THE MOLECULAR ENVELOPE OF CWLEO

    PubMed Central

    Prieto, L. Velilla; Cernicharo, J.; Quintana–Lacaci, G.; Agúndez, M.; Castro–Carrizo, A.; Fonfŕia, J. P.; Marcelino, N.; Zúñiga, J.; Requena, A.; Bastida, A.; Lique, F.; Guélin, M.

    2015-01-01

    We report the detection of SiS rotational lines in high-vibrational states as well as SiO and SiC2 lines in their ground vibrational state toward IRC+10216 during the Atacama Large Millimeter Array Cycle 0. The spatial distribution of these molecules shows compact emission for SiS and a more extended emission for SiO and SiC2, and also proves the existence of an increase in the SiC2 emission at the outer shells of the circumstellar envelope. We analyze the excitation conditions of the vibrationally excited SiS using the population diagram technique, and we use a large velocity gradient model to compare with the observations. We found moderate discrepancies between the observations and the models that could be explained if SiS lines detected are optically thick. Additionally, the line profiles of the detected rotational lines in the high energy vibrational states show a decreasing linewidth with increasing energy levels. This may be evidence that these lines could be excited only in the inner shells, i.e., the densest and hottest, of the circumstellar envelope of IRC+10216. PMID:26688711

  2. Tracing the Reionization Epoch with ALMA: [C II] Emission in z ˜ 7 Galaxies

    NASA Astrophysics Data System (ADS)

    Pentericci, L.; Carniani, S.; Castellano, M.; Fontana, A.; Maiolino, R.; Guaita, L.; Vanzella, E.; Grazian, A.; Santini, P.; Yan, H.; Cristiani, S.; Conselice, C.; Giavalisco, M.; Hathi, N.; Koekemoer, A.

    2016-09-01

    We present new results on [C ii]158 μ {{m}} emission from four galaxies in the reionization epoch. These galaxies were previously confirmed to be at redshifts between 6.6 and 7.15 from the presence of the Lyα emission line in their spectra. The Lyα emission line is redshifted by 100-200 km s-1 compared to the systemic redshift given by the [C ii] line. These velocity offsets are smaller than what is observed in z˜ 3 Lyman break galaxies (LBGs) with similar UV luminosities and emission line properties. Smaller velocity shifts reduce the visibility of Lyα and hence somewhat alleviate the need for a very neutral intergalactic medium at z˜ 7 to explain the drop in the fraction of Lyα emitters observed at this epoch. The galaxies show [C ii] emission with L[C ii] = 0.6 - 1.6× {10}8{L}⊙ : these luminosities place them consistently below the star formation rate (SFR)-L[C ii] relation observed for low-redshift star-forming and metal-poor galaxies and also below z = 5.5 LBGs with similar SFRs. We argue that previous undetections of [C ii] in z˜ 7 galaxies with similar or smaller SFRs are due to selection effects: previous targets were mostly strong Lyα emitters and therefore probably metal-poor systems, while our galaxies are more representative of the general high-redshift star-forming population.

  3. WEAK TURBULENCE IN THE HD 163296 PROTOPLANETARY DISK REVEALED BY ALMA CO OBSERVATIONS

    SciTech Connect

    Flaherty, Kevin M.; Hughes, A. Meredith; Rosenfeld, Katherine A.; Andrews, Sean M.; Wilner, David J.; Chiang, Eugene; Kerzner, Skylar; Simon, Jacob B.

    2015-11-10

    Turbulence can transport angular momentum in protoplanetary disks and influence the growth and evolution of planets. With spatially and spectrally resolved molecular emission line measurements provided by (sub)millimeter interferometric observations, it is possible to directly measure non-thermal motions in the disk gas that can be attributed to this turbulence. We report a new constraint on the turbulence in the disk around HD 163296, a nearby young A star, determined from Atacama Large Millimeter/submillimeter Array Science Verification observations of four CO emission lines (the CO(3-2), CO(2-1), {sup 13}CO(2-1), and C{sup 18}O(2-1) transitions). The different optical depths for these lines permit probes of non-thermal line-widths at a range of physical conditions (temperature and density) and depths into the disk interior. We derive stringent limits on the non-thermal motions in the upper layers of the outer disk such that any contribution to the line-widths from turbulence is <3% of the local sound speed. These limits are approximately an order of magnitude lower than theoretical predictions for full-blown magnetohydrodynamic turbulence driven by the magnetorotational instability, potentially suggesting that this mechanism is less efficient in the outer (R ≳ 30 AU) disk than has been previously considered.

  4. ALMA RESOLVES 30 DORADUS: SUB-PARSEC MOLECULAR CLOUD STRUCTURE NEAR THE CLOSEST SUPER STAR CLUSTER

    SciTech Connect

    Indebetouw, Remy; Brogan, Crystal; Leroy, Adam; Hunter, Todd; Kepley, Amanda E-mail: cbrogan@nrao.edu; and others

    2013-09-01

    We present Atacama Large (sub)Millimeter Array observations of 30 Doradus-the highest resolution view of molecular gas in an extragalactic star formation region to date ({approx}0.4 pc Multiplication-Sign 0.6 pc). The 30Dor-10 cloud north of R136 was mapped in {sup 12}CO 2-1, {sup 13}CO 2-1, C{sup 18}O 2-1, 1.3 mm continuum, the H30{alpha} recombination line, and two H{sub 2}CO 3-2 transitions. Most {sup 12}CO emission is associated with small filaments and clumps ({approx}<1 pc, {approx}10{sup 3} M{sub Sun} at the current resolution). Some clumps are associated with protostars, including ''pillars of creation'' photoablated by intense radiation from R136. Emission from molecular clouds is often analyzed by decomposition into approximately beam-sized clumps. Such clumps in 30 Doradus follow similar trends in size, linewidth, and surface density to Milky Way clumps. The 30 Doradus clumps have somewhat larger linewidths for a given size than predicted by Larson's scaling relation, consistent with pressure confinement. They extend to a higher surface density at a given size and linewidth compared to clouds studied at 10 pc resolution. These trends are also true of clumps in Galactic infrared-dark clouds; higher resolution observations of both environments are required. Consistency of clump masses calculated from dust continuum, CO, and the virial theorem reveals that the CO abundance in 30 Doradus clumps is not significantly different from the Large Magellanic Cloud mean, but the dust abundance may be reduced by {approx}2. There are no strong trends in clump properties with distance from R136; dense clumps are not strongly affected by the external radiation field, but there is a modest trend toward lower dense clump filling fraction deeper in the cloud.

  5. ALMA Resolves 30 Doradus: Sub-parsec Molecular Cloud Structure near the Closest Super Star Cluster

    NASA Astrophysics Data System (ADS)

    Indebetouw, Rémy; Brogan, Crystal; Chen, C.-H. Rosie; Leroy, Adam; Johnson, Kelsey; Muller, Erik; Madden, Suzanne; Cormier, Diane; Galliano, Frédéric; Hughes, Annie; Hunter, Todd; Kawamura, Akiko; Kepley, Amanda; Lebouteiller, Vianney; Meixner, Margaret; Oliveira, Joana M.; Onishi, Toshikazu; Vasyunina, Tatiana

    2013-09-01

    We present Atacama Large (sub)Millimeter Array observations of 30 Doradus—the highest resolution view of molecular gas in an extragalactic star formation region to date (~0.4 pc × 0.6 pc). The 30Dor-10 cloud north of R136 was mapped in 12CO 2-1, 13CO 2-1, C18O 2-1, 1.3 mm continuum, the H30α recombination line, and two H2CO 3-2 transitions. Most 12CO emission is associated with small filaments and clumps (lsim1 pc, ~103 M ⊙ at the current resolution). Some clumps are associated with protostars, including "pillars of creation" photoablated by intense radiation from R136. Emission from molecular clouds is often analyzed by decomposition into approximately beam-sized clumps. Such clumps in 30 Doradus follow similar trends in size, linewidth, and surface density to Milky Way clumps. The 30 Doradus clumps have somewhat larger linewidths for a given size than predicted by Larson's scaling relation, consistent with pressure confinement. They extend to a higher surface density at a given size and linewidth compared to clouds studied at 10 pc resolution. These trends are also true of clumps in Galactic infrared-dark clouds; higher resolution observations of both environments are required. Consistency of clump masses calculated from dust continuum, CO, and the virial theorem reveals that the CO abundance in 30 Doradus clumps is not significantly different from the Large Magellanic Cloud mean, but the dust abundance may be reduced by ~2. There are no strong trends in clump properties with distance from R136; dense clumps are not strongly affected by the external radiation field, but there is a modest trend toward lower dense clump filling fraction deeper in the cloud.

  6. Weak Turbulence in the HD 163296 Protoplanetary Disk Revealed by ALMA CO Observations

    NASA Astrophysics Data System (ADS)

    Flaherty, Kevin M.; Hughes, A. Meredith; Rosenfeld, Katherine A.; Andrews, Sean M.; Chiang, Eugene; Simon, Jacob B.; Kerzner, Skylar; Wilner, David J.

    2015-11-01

    Turbulence can transport angular momentum in protoplanetary disks and influence the growth and evolution of planets. With spatially and spectrally resolved molecular emission line measurements provided by (sub)millimeter interferometric observations, it is possible to directly measure non-thermal motions in the disk gas that can be attributed to this turbulence. We report a new constraint on the turbulence in the disk around HD 163296, a nearby young A star, determined from Atacama Large Millimeter/submillimeter Array Science Verification observations of four CO emission lines (the CO(3-2), CO(2-1), 13CO(2-1), and C18O(2-1) transitions). The different optical depths for these lines permit probes of non-thermal line-widths at a range of physical conditions (temperature and density) and depths into the disk interior. We derive stringent limits on the non-thermal motions in the upper layers of the outer disk such that any contribution to the line-widths from turbulence is <3% of the local sound speed. These limits are approximately an order of magnitude lower than theoretical predictions for full-blown magnetohydrodynamic turbulence driven by the magnetorotational instability, potentially suggesting that this mechanism is less efficient in the outer (R ≳ 30 AU) disk than has been previously considered.

  7. ALMA imaging of SDP.81 - I. A pixelated reconstruction of the far-infrared continuum emission

    NASA Astrophysics Data System (ADS)

    Rybak, M.; McKean, J. P.; Vegetti, S.; Andreani, P.; White, S. D. M.

    2015-07-01

    We present a sub-50 parsec scale analysis of the gravitational lens system SDP.81 at redshift 3.042 using Atacama Large Millimetre/submillimetre Array science verification data. We model both the mass distribution of the gravitational lensing galaxy and the pixelated surface brightness distribution of the background source using a novel Bayesian technique that fits the data directly in visibility space. We find the 1 and 1.3 mm dust emission to be magnified by a factor of μtot = 17.6 ± 0.4, giving an intrinsic total star formation rate of 315 ± 60 M⊙ yr-1 and a dust mass of 6.4 ± 1.5 × 108 M⊙. The reconstructed dust emission is found to be non-uniform, but composed of multiple regions that are heated by both diffuse and strongly clumped star formation. The highest surface brightness region is a ˜1.9 × 0.7 kpc disc-like structure, whose small extent is consistent with a potential size-bias in gravitationally lensed starbursts. Although surrounded by extended star formation, with a density of 20-30 ± 10 M⊙ yr-1 kpc-2, the disc contains three compact regions with densities that peak between 120 and 190 ± 20 M⊙ yr-1 kpc-2. Such star formation rate densities are below what is expected for Eddington-limited star formation by a radiation pressure supported starburst. There is also a tentative variation in the spectral slope of the different star-forming regions, which is likely due to a change in the dust temperature and/or opacity across the source.

  8. Dust Production and Particle Acceleration in Supernova 1987A Revealed with ALMA

    NASA Technical Reports Server (NTRS)

    Indebetouw, R.; Matsuura, M.; Dwek, E.; Zanardo, G.; Barlow, M. J.; Baes, M.; Bouchet, P.; Burrows, D. N.; Chevalier, R.; Clayton, G. C.; Fransson, C.; Gaensler, B.; Kirshner, R.; Lakicevic, M.; Long, K. S.; Lundqvist, P.; Marti-Vidal, I.; Marcaide, J.; McCray, R.; Meixner, M.; Ng, C.-Y.; Park, S.; Sonneborn, G.; Staveley-Smith, L.; vanLoon, J.

    2014-01-01

    Supernova (SN) explosions are crucial engines driving the evolution of galaxies by shock heating gas, increasing the metallicity, creating dust, and accelerating energetic particles. In 2012 we used the Atacama Large Millimeter/ Submillimeter Array to observe SN1987A, one of the best-observed supernovae since the invention of the telescope. We present spatially resolved images at 450 µm, 870 µm, 1.4 mm, and 2.8 mm, an important transition wavelength range. Longer wavelength emission is dominated by synchrotron radiation from shock-accelerated particles, shorter wavelengths by emission from the largest mass of dust measured in a supernova remnant (>0.2 Solar Mass). For the first time we show unambiguously that this dust has formed in the inner ejecta (the cold remnants of the exploded star's core). The dust emission is concentrated at the center of the remnant, so the dust has not yet been affected by the shocks. If a significant fraction survives, and if SN 1987A is typical, supernovae are important cosmological dust producers.

  9. DUST PRODUCTION AND PARTICLE ACCELERATION IN SUPERNOVA 1987A REVEALED WITH ALMA

    SciTech Connect

    Indebetouw, R.; Chevalier, R.; Matsuura, M.; Barlow, M. J.; Dwek, E.; Zanardo, G.; Baes, M.; Bouchet, P.; Burrows, D. N.; Clayton, G. C.; Fransson, C.; Lundqvist, P.; Gaensler, B.; Kirshner, R.; Lakićević, M.; Long, K. S.; Meixner, M.; Martí-Vidal, I.; Marcaide, J.; and others

    2014-02-10

    Supernova (SN) explosions are crucial engines driving the evolution of galaxies by shock heating gas, increasing the metallicity, creating dust, and accelerating energetic particles. In 2012 we used the Atacama Large Millimeter/Submillimeter Array to observe SN 1987A, one of the best-observed supernovae since the invention of the telescope. We present spatially resolved images at 450 μm, 870 μm, 1.4 mm, and 2.8 mm, an important transition wavelength range. Longer wavelength emission is dominated by synchrotron radiation from shock-accelerated particles, shorter wavelengths by emission from the largest mass of dust measured in a supernova remnant (>0.2 M {sub ☉}). For the first time we show unambiguously that this dust has formed in the inner ejecta (the cold remnants of the exploded star's core). The dust emission is concentrated at the center of the remnant, so the dust has not yet been affected by the shocks. If a significant fraction survives, and if SN 1987A is typical, supernovae are important cosmological dust producers.

  10. ALMA Multi-line Imaging of the Nearby Starburst NGC 253

    NASA Astrophysics Data System (ADS)

    Meier, David S.; Walter, Fabian; Bolatto, Alberto D.; Leroy, Adam K.; Ott, Jürgen; Rosolowsky, Erik; Veilleux, Sylvain; Warren, Steven R.; Weiß, Axel; Zwaan, Martin A.; Zschaechner, Laura K.

    2015-03-01

    We present spatially resolved (~50 pc) imaging of molecular gas species in the central kiloparsec of the nearby starburst galaxy NGC 253, based on observations taken with the Atacama Large Millimeter/submillimeter Array. A total of 50 molecular lines are detected over a 13 GHz bandwidth imaged in the 3 mm band. Unambiguous identifications are assigned for 27 lines. Based on the measured high CO/C17O isotopic line ratio (gsim350), we show that 12CO(1-0) has moderate optical depths. A comparison of the HCN and HCO+ with their 13C-substituted isotopologues shows that the HCN(1-0) and HCO+(1-0) lines have optical depths at least comparable to CO(1-0). H13CN/H13CO+ (and H13CN/HN13C) line ratios provide tighter constraints on dense gas properties in this starburst. SiO has elevated abundances across the nucleus. HNCO has the most distinctive morphology of all the bright lines, with its global luminosity dominated by the outer parts of the central region. The dramatic variation seen in the HNCO/SiO line ratio suggests that some of the chemical signatures of shocked gas are being erased in the presence of dominating central radiation fields (traced by C2H and CN). High density molecular gas tracers (including HCN, HCO+, and CN) are detected at the base of the molecular outflow. We also detect hydrogen β recombination lines that, like their α counterparts, show compact, centrally peaked morphologies, distinct from the molecular gas tracers. A number of sulfur based species are mapped (CS, SO, NS, C2S, H2CS, and CH3SH) and have morphologies similar to SiO.

  11. ALMA MULTI-LINE IMAGING OF THE NEARBY STARBURST NGC 253

    SciTech Connect

    Meier, David S.; Walter, Fabian; Zschaechner, Laura K.; Bolatto, Alberto D.; Veilleux, Sylvain; Warren, Steven R.; Leroy, Adam K.; Ott, Jürgen; Rosolowsky, Erik; Weiß, Axel; Zwaan, Martin A.

    2015-03-01

    We present spatially resolved (∼50 pc) imaging of molecular gas species in the central kiloparsec of the nearby starburst galaxy NGC 253, based on observations taken with the Atacama Large Millimeter/submillimeter Array. A total of 50 molecular lines are detected over a 13 GHz bandwidth imaged in the 3 mm band. Unambiguous identifications are assigned for 27 lines. Based on the measured high CO/C{sup 17}O isotopic line ratio (≳350), we show that {sup 12}CO(1-0) has moderate optical depths. A comparison of the HCN and HCO{sup +} with their {sup 13}C-substituted isotopologues shows that the HCN(1-0) and HCO{sup +}(1-0) lines have optical depths at least comparable to CO(1-0). H{sup 13}CN/H{sup 13}CO{sup +} (and H{sup 13}CN/HN{sup 13}C) line ratios provide tighter constraints on dense gas properties in this starburst. SiO has elevated abundances across the nucleus. HNCO has the most distinctive morphology of all the bright lines, with its global luminosity dominated by the outer parts of the central region. The dramatic variation seen in the HNCO/SiO line ratio suggests that some of the chemical signatures of shocked gas are being erased in the presence of dominating central radiation fields (traced by C{sub 2}H and CN). High density molecular gas tracers (including HCN, HCO{sup +}, and CN) are detected at the base of the molecular outflow. We also detect hydrogen β recombination lines that, like their α counterparts, show compact, centrally peaked morphologies, distinct from the molecular gas tracers. A number of sulfur based species are mapped (CS, SO, NS, C{sub 2}S, H{sub 2}CS, and CH{sub 3}SH) and have morphologies similar to SiO.

  12. Exploring Molecular Complexity with ALMA: Deuterated complex organic molecules in Sgr B2

    NASA Astrophysics Data System (ADS)

    Belloche, A.; Müller, H. S. P.; Garrod, R. T.; Menten, K. M.

    2016-05-01

    Apart from the case of methanol, little is known about deuterium fractionation of complex organic molecules in the interstellar medium, especially in high mass star forming regions. We take advantage of the EMoCA spectral line survey to search for deuterated complex organic molecules toward the hot molecular core Sgr B2(N2). We report the secure detection of CH2DCN with a deuteration level of 0.4% and tentative detections of CH2DOH, CH2DCH2CN, CH3CHDCN, and DC3N with levels in the range 0.05-0.12%. Except for methyl cyanide, the measured deuteration levels lie at least a factor of four below the predictions of current astrochemical models. They are also lower than in Orion KL by a factor of a few up to a factor ten. These discrepancies and differences may be due to the higher temperatures that prevail in the Galactic Center region compared to nearby clouds, or they may result from a lower overall abundance of deuterium itself in the Galactic Center region by up to a factor ten.

  13. Factors Associated with Non-Traditional and Traditional Undergraduate Alumni Giving to Alma Maters

    ERIC Educational Resources Information Center

    Johnson, Elizabeth Ann Miller

    2013-01-01

    Both public and private institutions of higher education face revenue shortfalls. In order to close budget gaps, colleges and universities must identify new revenue sources. Historically alumni are large providers of voluntary support to higher education institutions, but the numbers of alumni contributing financially is decreasing. The purpose of…

  14. Alma view of G0.253+0.016: Can cloud-cloud collision form the cloud?

    SciTech Connect

    Higuchi, Aya E.; Chibueze, James O.; Habe, Asao; Takahira, Ken; Takano, Shuro E-mail: ahiguchi@mx.ibaraki.ac.jp

    2014-06-01

    We present the results of the sulfur monoxide, SO, line emission observations of G0.253+0.016 with the Atacama Large Millimeter/Submillimeter Array at an angular resolution of 1.''7. The dense and massive molecular cloud of G0.253+0.016 is highly sub-structured, yet it shows no obvious signs of cluster formation. We found three outstanding features of the cloud from the SO emission, namely, shell structure with a radius of 1.3 pc, large velocity gradients of 20 km s{sup –1} pc{sup –1} with the cloud, and cores with large velocity dispersions (30-40 km s{sup –1}) around the shell structure. We suggest that these large-velocity dispersion cores will form high-mass stars in the future. In an attempt to explore the formation scenario of the dense cloud, we compared our results with numerical simulations; therefore, we propose that G0.253+0.016 may have formed due to a cloud-cloud collision process.

  15. News and Views: ALMA examines Centaurus A; WMAP team wins Gruber Prize; EUCLID moves closer to launch

    NASA Astrophysics Data System (ADS)

    2012-08-01

    Charles Bennett (right) and the team behind the Wilkinson Microwave Anisotropy Probe received the 2012 Gruber Prize, in recognition of the precision of their results that have turned an “appealing scenario into precise science”. ESA's dark energy and dark matter mission, EUCLID, has received approval from the Science Programme Committee to move into the full contruction phase, ahead of launch in 2020.

  16. ALMA observations of the T Tauri binary system AS 205: evidence for molecular winds and/or binary interactions

    SciTech Connect

    Salyk, Colette; Pontoppidan, Klaus; Corder, Stuartt; Muñoz, Diego; Zhang, Ke; Blake, Geoffrey A.

    2014-09-01

    In this study, we present high-resolution millimeter observations of the dust and gas disk of the T Tauri star AS 205 N and its companion, AS 205 S, obtained with the Atacama Large Millimeter Array. The gas disk around AS 205 N, for which infrared emission spectroscopy demonstrates significant deviations from Keplerian motion that has been interpreted as evidence for a disk wind, also displays significant deviations from Keplerian disk emission in the observations presented here. Detections near both AS 205 N and S are obtained in 1.3 mm continuum, {sup 12}CO 2-1, {sup 13}CO 2-1, and C{sup 18}O 2-1. The {sup 12}CO emission is extended up to ∼2'' from AS 205 N, and both {sup 12}CO and {sup 13}CO display deviations from Keplerian rotation at all angular scales. Two possible explanations for these observations hold up best to close scrutiny—tidal interaction with AS 205 S or disk winds (or a combination of the two)—and we discuss these possibilities in some detail.

  17. Free-free and H42α emission from the dusty starburst within NGC 4945 as observed by ALMA

    NASA Astrophysics Data System (ADS)

    Bendo, G. J.; Henkel, C.; D'Cruze, M. J.; Dickinson, C.; Fuller, G. A.; Karim, A.

    2016-11-01

    We present observations of the 85.69 GHz continuum emission and H42α line emission from the central 30 arcsec within NGC 4945. Both sources of emission originate from nearly identical structures that can be modelled as exponential discs with scalelengths of ˜2.1 arcsec (or ˜40 pc). An analysis of the spectral energy distribution based on combining these data with archival data imply that 84 ± 10 per cent of the 85.69 GHz continuum emission originates from free-free emission. The electron temperature is 5400 ± 600 K, which is comparable to what has been measured near the centre of the Milky Way Galaxy. The star formation rate (SFR) based on the H42α and 85.69 GHz free-free emission (and using a distance of 3.8 Mpc) is 4.35 ± 0.25 M⊙ yr-1. This is consistent with the SFR from the total infrared flux and with previous measurements based on recombination line emission, and it is within a factor of ˜2 of SFRs derived from radio data. The Spitzer Space Telescope 24 μm data and Wide-field Infrared Survey Explorer 22 μm data yield SFRs ˜10× lower than the Atacama Large Millimeter/submillimeter Array measurements, most likely because the mid-infrared data are strongly affected by dust attenuation equivalent to AV = 150. These results indicate that SFRs based on mid-infrared emission may be highly inaccurate for dusty, compact circumnuclear starbursts.

  18. AN INFRARED-LUMINOUS MERGER WITH TWO BIPOLAR MOLECULAR OUTFLOWS: ALMA AND SMA OBSERVATIONS OF NGC 3256

    SciTech Connect

    Sakamoto, Kazushi; Aalto, Susanne; Combes, Francoise; Evans, Aaron; Peck, Alison

    2014-12-20

    We report Atacama Large Millimeter/sub-millimeter Array and Submillimeter Array observations of the infrared-luminous merger NGC 3256, the most luminous galaxy within z = 0.01. Both of the two merger nuclei separated by 5'' (0.8 kpc) have a molecular gas concentration, a nuclear disk, with Σ{sub mol} > 10{sup 3} M {sub ☉} pc{sup –2}. The northern nucleus is more massive and is surrounded by molecular spiral arms. Its nuclear disk is face-on, while the southern nuclear disk is almost edge-on. The high-velocity molecular gas in the system can be resolved into two molecular outflows from the two nuclei. The one from the northern nucleus is part of a starburst-driven superwind seen nearly pole-on. Its maximum velocity is >750 km s{sup –1} and its mass outflow rate is >60 M {sub ☉} yr{sup –1} for a conversion factor X{sub CO}=N{sub H{sub 2}}/I{sub CO(1−0)} of 1 × 10{sup 20} cm{sup –2} (K km s{sup –1}){sup –1}. The molecular outflow from the southern nucleus is a highly collimated bipolar jet seen nearly edge-on. Its line-of-sight velocity increases with distance, out to 300 pc from the nucleus, to the maximum de-projected velocity of ∼2000 km s{sup –1} for the estimated inclination and ≳1000 km s{sup –1} taking into account the uncertainty. Its mass outflow rate is estimated to be >50 M {sub ☉} yr{sup –1} for the same X {sub CO}. This southern outflow has indications of being driven by a bipolar radio jet from an active galactic nucleus that recently weakened. The sum of these outflow rates, although subject to the uncertainty in the molecular mass estimate, either exceeds or compares to the total star formation rate. The feedback from nuclear activity through molecular outflows is therefore significant in the gas consumption, and hence evolution, of this system.

  19. AN ALMA SURVEY OF SUBMILLIMETER GALAXIES IN THE EXTENDED CHANDRA DEEP FIELD SOUTH: NEAR-INFRARED MORPHOLOGIES AND STELLAR SIZES

    SciTech Connect

    Chen, Chian-Chou; Smail, Ian; Swinbank, A. M.; Simpson, J. M.; Ma, Cheng-Jiun; Alexander, D. M.; Danielson, A. L. R.; Edge, A. C.; Biggs, A. D.; Ivison, R. J.; Brandt, W. N.; Chapman, S. C.; Coppin, K. E. K.; Dannerbauer, H.; Greve, T. R.; Karim, A.; Menten, Karl M.; Schinnerer, E.; Walter, F.; Wardlow, J. L.; and others

    2015-02-01

    We analyze Hubble Space Telescope WFC3/H {sub 160}-band observations of a sample of 48 Atacama Large Millimeter/submillimeter Array detected submillimeter galaxies (SMGs) in the Extended Chandra Deep Field South field, to study their stellar morphologies and sizes. We detect 79% ± 17% of the SMGs in the H {sub 160}-band imaging with a median sensitivity of 27.8 mag, and most (80%) of the nondetections are SMGs with 870 μm fluxes of S {sub 870} < 3 mJy. With a surface brightness limit of μ {sub H} ∼ 26 mag arcsec{sup –2}, we find that 82% ± 9% of the H {sub 160}-band-detected SMGs at z = 1-3 appear to have disturbed morphologies, meaning they are visually classified as either irregulars or interacting systems, or both. By determining a Sérsic fit to the H {sub 160} surface brightness profiles, we derive a median Sérsic index of n = 1.2 ± 0.3 and a median half-light radius of r{sub e} = 4.4{sub −0.5}{sup +1.1} kpc for our SMGs at z = 1-3. We also find significant displacements between the positions of the H {sub 160} component and 870 μm emission in these systems, suggesting that the dusty starburst regions and less-obscured stellar distribution are not colocated. We find significant differences in the sizes and the Sérsic index between our z = 2-3 SMGs and z ∼ 2 quiescent galaxies, suggesting that a major transformation of the stellar light profile is needed in the quenching processes if SMGs are progenitors of the red-and-dead z ∼ 2 galaxies. Given the short-lived nature of SMGs, we postulate that the majority of the z = 2-3 SMGs with S {sub 870} ≳ 2 mJy are early/mid-stage major mergers.

  20. A RECENT ACCRETION BURST IN THE LOW-MASS PROTOSTAR IRAS 15398-3359: ALMA IMAGING OF ITS RELATED CHEMISTRY

    SciTech Connect

    Jørgensen, Jes K.; Brinch, Christian; Lindberg, Johan E.; Bisschop, Suzanne E.; Visser, Ruud; Bergin, Edwin A.; Sakai, Nami; Yamamoto, Satoshi; Harsono, Daniel; Van Dishoeck, Ewine F.; Persson, Magnus V.

    2013-12-20

    Low-mass protostars have been suggested to show highly variable accretion rates throughout their evolution. Such changes in accretion, and related heating of their ambient envelopes, may trigger significant chemical variations on different spatial scales and from source-to-source. We present images of emission from C{sup 17}O, H{sup 13}CO{sup +}, CH{sub 3}OH, C{sup 34}S and C{sub 2}H toward the low-mass protostar IRAS 15398-3359 on 0.''5 (75 AU diameter) scales with the Atacama Large Millimeter/submillimeter Array at 340 GHz. The resolved images show that the emission from H{sup 13}CO{sup +} is only present in a ring-like structure with a radius of about 1-1.''5 (150-200 AU) whereas the CO and other high dipole moment molecules are centrally condensed toward the location of the central protostar. We propose that HCO{sup +} is destroyed by water vapor present on small scales. The origin of this water vapor is likely an accretion burst during the last 100-1000 yr increasing the luminosity of IRAS 15398-3359 by a factor of 100 above its current luminosity. Such a burst in luminosity can also explain the centrally condensed CH{sub 3}OH and extended warm carbon-chain chemistry observed in this source and furthermore be reflected in the relative faintness of its compact continuum emission compared to other protostars.

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