xrs astro-e high: Topics by Science.gov

Sample records for xrs astro-e high

The Astro-E/XRS Blocking Filter Calibration

NASA Technical Reports Server (NTRS)

Audley, Michael D.; Arnaud, Keith A.; Gendreau, Keith C.; Boyce, Kevin R.; Fleetwood, Charles M.; Kelley, Richard L.; Keski-Kuha, Ritva A.; Porter, F. Scott; Stahle, Caroline K.; Szymkowiak, Andrew E.

1999-01-01

We describe the transmission calibration of the Astro-E XRS blocking filters. The XRS instrument has five aluminized polyimide blocking filters. These filters are located at thermal stages ranging from 200 K to 60 mK. They are each about 1000 A thick. XRS will have high energy resolution which will enable it to see some of the extended fine structure around the oxygen and aluminum K edges of these filters. Thus, we are conducting a high spectral resolution calibration of the filters near these energies to resolve out extended flue structure and absorption lines.
Performance of the XRS/ASTRO-E engineering model ADR.

NASA Astrophysics Data System (ADS)

Serlemitsos, A. T.; Sansebastian, M.; Kunes, E. S.; Behr, J.

1999-04-01

NASA's Goddard Space Flight Center (GSFC) has developed an X-ray Spectrometer (XRS) to be flown aboard ASTRO-E, in cooperation with the Japanese Institute of Space and Astronomical Science (ISAS). XRS uses an array of 32 microcalorimeters capable of detecting X-rays in the energy range of 0.3 - 10 keV with a resolution of 12 eV. In order to accomplish this, the detectors must be operated at a temperature of 0.065K. In space, an Adiabatic Demagnetization Refrigerator (ADR) must be used to cool the detectors to that temperature. A spaceworthy ADR has been developed at GSFC to be used in the XRS. Originally, the ADR was developed to be flown aboard the Advanced X-ray Astrophysics Facility (AXAF). The allowable average thermal load of the ADR to the LHe dewar was changed from 2.6 mW to 270 μW. Time constraints did not allow a complete redesign of the ADR. The original shape and size were left unchanged and the new specifications were met by streamlining the heat switch and lengthening the salt pill magnetization cycle time. For a LHe bath temperature of 1.3K the gas gap heat switch presently used has an on/off ratio of 22000 and a parasitic heat leak of 2.9 μW/K.
The Astro-E2 Mission

NASA Technical Reports Server (NTRS)

Kelley, Richard L.

2004-01-01

The Astro-E2 observatory is a rebuild of the original Astro-E observatory that was lost during launch in February 2000. It is scheduled for launch into low earth orbit on a Japanese M-V rocket in early 2005. The Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, is developing the observatory with major contributions from the US. The three instruments on the observatory are the high-resolution x-ray spectrometer (the XRS) featuring a 30-pixel x-ray microcalorimeter array, a set of four CCD cameras (the XIS) and a combination photo-diode/scintillator detector system (the HXD) that will extend the band pass up to nearly 700 keV. A significant feature of Astro-E2 is that all of the instruments are coaligned and operated simultaneously. With its high spectral resolution and collecting area for spectroscopy above 1 keV, Astro-E2 should enable major discovery space and pioneer new technology for use in space. Prime areas for investigation are supernova remnants, active galaxies and the measurement of black hole properties via relativistically-broadened Fe-K emission galaxies. A number of enhancements have been made for the Astro-E2/XRS, including a higher resolution microcalorimeter array, ii mechanical cooler for longer cryogen life, and an improved in-flight calibration system. The Astro-E2/XIS has also been improved to include two back-side-illuminated CCDs to enhance the low energy response. Improvements have also been made to the x-ray mirrors used for both the XRS and XIS to sharpen the point spread function and reduce the effects of stray light. In this talk we will present the essential features of Astro-E2, paying particular attention to the enhancements, and describe the major scientific strengths of the observatory.
Design and Performance of the Astro-E/XRS Signal Processing System

NASA Technical Reports Server (NTRS)

Boyce, Kevin R.; Audley, M. D.; Baker, R. G.; Dumonthier, J. J.; Fujimoto, R.; Gendreau, K. C.; Ishisaki, Y.; Kelley, R. L.; Stahle, C. K.; Szymkowiak, A. E.

1999-01-01

We describe the signal processing system of the Astro-E XRS instrument. The Calorimeter Analog Processor (CAP) provides bias and power for the detectors and amplifies the detector signals by a factor of 20,000. The Calorimeter Digital Processor (CDP) performs the digital processing of the calorimeter signals, detecting X-ray pulses and analyzing them by optimal filtering. We describe the operation of pulse detection, Pulse height analysis. and risetime determination. We also discuss performance, including the three event grades (hi-res mid-res, and low-res). anticoincidence detection, counting rate dependence, and noise rejection.
Proposal Tools for ASTRO-E

NASA Astrophysics Data System (ADS)

Mukai, K.; ASTRO-E Guest Observer Facility Team

1998-12-01

The XRS instrument on board ASTRO-E is expected to last about two years, before it runs out of cryogen. This leads us to place a particular emphasis on the technical aspects of the observing proposals to maximize the scientific return, more so than for missions/instruments with longer life times. In this talk, we will introduce the tools that we provide for you to write technically sound ASTRO-E XRS proposals. They include PIMMS/W3pimms and xspec/WebSpec for exposure time calculation, simaste for more detailed simulations (particularly of extended sources), and Wasabi, the Web-based observation visualization tool.
Laboratory Astrophysics Using a Spare XRS Microcalorimeter

NASA Technical Reports Server (NTRS)

Audley, M. Damian; Beiersdorfer, Peter; Porter, Frederick Scott; Brown, Gregory; Boyce, Kevin R.; Brekosky, Regis; Brown, Gregory V.; Gendreau, Keith C.; Gygax, John; Kahn, Steve;

2000-01-01

The XRS instrument on Astro-E is a fully self-contained microcalorimeter x-ray instrument capable of acquiring optimally filtering, and characterizing events for 32 independent pixels. With the launch of the Astro-E spacecraft, a full flight spare detector system has been integrated into a laboratory cryostat for use on the electron beam ion trap (EBIT) at Lawrence Livermore National Laboratory. The detector system contains a microcalorimeter array with 32 instrumented pixels heat sunk to 60 mK using an adiabatic demagnetization refrio,erator. The instrument has a composite resolution of 8eV at 1 keV and 12eV at 6 keV with a minimum of 95% quantum efficiency. This will allow high spectral resolution, broadband observations of collisionally excited plasmas which are produced in the EBIT experiment. Unique to our instrument are exceptionally well characterized 1000 Angstrom thick aluminum on polyimide infrared blocking filters. The detailed transmission function including the edc,e fine structure of these filters has been measured in our laboratory using an erect field grating spectrometer. This will allow the instrument to perform the first broadband absolute flux measurements with the EBIT instrument. The instrument performance as well as the results of preliminary measurements will be discussed. Work performed under the auspices of the U.S. D.o.E. by Lawrence Livermore National Laboratory under contract W-7405-ENG-48 and was supported by the NASA High Energy Astrophysics Supporting Research and Technology Program.

System Design and Implementation of the Detector Assembly of the Astro-H Soft X-Ray Spectrometer

NASA Technical Reports Server (NTRS)

Chiao, M. P.; Adams, J.; Goodwin, P.; Hobson, C.W.; Kelley, R. L.; Kilbourne, C. A.; McCammom, D.; McGuinness, D. S.; Moseley, S. J.; Porter, F. S.;

2016-01-01

The soft x-ray spectrometer (SXS) onboard Astro-H presents to the science community unprecedented capability (less than 7 eV at 6 keV) for high-resolution spectral measurements in the range of 0.5-12 keV to study extended celestial sources. At the heart of this SXS is the x-ray calorimeter spectrometer (XCS) where detectors (calorimeter array and anticoincidence detector) operate at 50 mK, the bias circuit operates at nominal 1.3 K, and the first stage amplifiers operateat 130 K, all within a nominal 20 cm envelope. The design of the detector assembly in this XCS originates from the Astro-E x-ray spectrometer (XRS) and lessons learned from Astro-E and Suzaku. After the production of our engineering model, additional changes were made in order to improve our flight assembly process for better reliability and overall performance. In this poster, we present the final design and implementation of the flight detector assembly, show comparison of parameters and performance to Suzakus XRS, and list susceptibilities to other subsystems as well as our lessons learned.

Astro-E2 Magnesium Diboride High Current Leads

NASA Technical Reports Server (NTRS)

Panek, J. S.; Tuttle, J. G.; Riall, S.; Mustafi, S.; Gray, A.; Edmonds, R.; Marrero, V.

2003-01-01

The recent discovery of superconducting properties in MgB_2 and rapid development of small diameter steel-clad wires has opened up the possibility of enhancing the design of the baseline Astro-E2 high current lead assembly. Replacing YBCO filaments with MgB_2 wires and modifying the heat sink location can give much higher margins against quench from temperature oscillations of the 4 K heat sink, although wih some overall thermal penalty. The design and performance of a new lead assembly during flight qualification is discussed, with emphasis on thermal, structural, and electrical test results.
The X-ray Mirrors for the Astro-E2 Mission

NASA Technical Reports Server (NTRS)

Chan, Kai-Wing; Soong, Yang; Serlemitsos, Peter J.; White, Nicholas E. (Technical Monitor)

2002-01-01

The X-Ray telescopes (XRT) for the US/Japan collaborative mission Astro-E2 will be of the same basic design as those built for the original Astro-E mission which failed to reach orbit in Feb. 2000. The NASA/GSFC X-ray Astrophysics Branch will again provide the five lightweight, broad-band mirrors for the mission. X-ray calibrations of the mirrors delivered for the original Astro-E instrument showed spatial resolutions characterized by Half-Power Diameters (HPD) in the range of 1.8 - 2.2 minutes of arc, essentially independent of photon energy in the soft X-ray band. For the mission Astro-E2, both funding constraints and management decisions drastically limit any design modifications, so reflector fabrication and assembly procedures have remained largely unchanged. Nevertheless, in view of the importance in scientific return of attaining even a modest improvement in the spatial resolution of these mirrors, we have carefully considered the various sources of spatial error and, whenever possible, incorporated promising modifications. In this paper, we discuss our current understanding of the various error components as well as the small changes we have been able to implement.
High Energy Astrophysics Program

NASA Technical Reports Server (NTRS)

1996-01-01

This report reviews activities performed-by members of the USRA contract team during the six months of the reporting period and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, visiting the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics. Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA); X-ray Timing Experiment (XTE); X-ray Spectrometer (XRS); Astro-E; High Energy Astrophysics Science Archive Research Center (HEASARC), and others.
High Energy Astrophysics Program (HEAP)

NASA Technical Reports Server (NTRS)

Angelini, Lorella; Corcoran, Michael; Drake, Stephen; McGlynn, Thomas A.; Snowden, Stephen; Mukai, Koji; Cannizzo, John; Lochner, James; Rots, Arnold; Christian, Eric;

1998-01-01

This report reviews activities performed by the members of the USRA contract team during the 6 months of the reporting period and projected activities during the coming 6 months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in astrophysics. Supported missions include advanced Satellite for Cosmology and Astrophysics (ASCA), X-Ray Timing Experiment (XTE), X-Ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science Archive Research Center (HEASARC) and others.

High Energy Astrophysics Program (HEAP)

NASA Technical Reports Server (NTRS)

Angelini, L.

1998-01-01

This report reviews activities performed by members of the USRA contract team during the six months of the reporting period and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA), X-ray Timing Experiment (XTE), X-ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science Archive Research Center (HEASARC), and others.
High Energy Astrophysics Program

NASA Technical Reports Server (NTRS)

1996-01-01

This report reviews activities performed by members of the USRA (Universities Space Research Association) contract team during the six months during the reporting period (10/95 - 3/96) and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics. Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA), X-ray Timing Experiment (XTE), X-ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science, Archive Research Center (HEASARC), and others.
High Energy Astrophysics Research and Programmatic Support

NASA Technical Reports Server (NTRS)

Angelini, Lorella

1998-01-01

This report reviews activities performed by members of the USRA contract team during the six months of the reporting period and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics. Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA), X-ray Timing Experiment (XTE), X-ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science Archive Research Center (HEASARC), and others.
High Energy Astrophysics Research and Programmatic Support

NASA Technical Reports Server (NTRS)

Angelini, L. (Editor)

1997-01-01

This report reviews activities performed by members of the USRA contract team during the six months of the reporting period and projected activities during the coming six months. Activities take place at the Goddard Space Flight Center, within the Laboratory for High Energy Astrophysics. Developments concern instrumentation, observation, data analysis, and theoretical work in Astrophysics. Missions supported include: Advanced Satellite for Cosmology and Astrophysics (ASCA), X-ray Timing Experiment (XTE), X-ray Spectrometer (XRS), Astro-E, High Energy Astrophysics Science Archive Research Center (HEASARC), and others.
IXO-XMS LVSID Anti-Coincidence Detector

NASA Technical Reports Server (NTRS)

Porter, Scott F.; Kilbourne, Caroline

2010-01-01

This document describes a high-TRL backup implementation of the anti-coincidence detector for the IXO/XMS instrument. The backup detector, hereafter referred to as the low-voltage silicon ionization detector (LVSID), has been successfully flown on Astro-E2 (Suzaku)/XRS and is currently being implemented, without significant changes, on the Astro-H/SXS instrument. The LVSID anti-coincidence detector on Astro-E2/XRS operated successfully for almost 2 years, and was not affected by the loss of liquid helium in that instrument. The LVSID continues to operate after almost 5 years on-orbit (LEO, 550 km) but with slightly increased noise following the expected depletion of solid Neon after 22 months. The noise of the device is increased after the loss of sNe due to thermally induced bias and readout noise. No radiation damage, or off-nominal affects have been observed with the LVSID on-orbit during the Astro-E2/XRS program. A detector die from the same fabrication run will be used on the Astro-H/SXS mission. The LVSID technology and cryogenic JFET readout system is thus TRL 9. The technology is described in detail in section 2. The IXO/XMS "backup-up" anti-coincidence detector is a small array of LVSID detectors that are almost identical to those employed for Astro -E2/XRS as described in this document. The readout system is identical and, infact would use the same design as the Astro -E2/XRS JFET amplifier module (19 channels) essentially without changes except for its mechanical mount. The changes required for the IXO/XMS LVSID array are limited to the mounting of the LVSID detectors, and the mechanical mounting of the JFET amplifier sub-assembly. There is no technical development needed for the IXO/XMS implementation and the technology is ready for detailed design-work leading to PDR. The TRL level is thus at least 6, and possibly higher. Characteristics of an IXO/XMS LVSID anti-co detector are given in Table 1 and described in detail in section 3.
The Detector Subsystem for the SXS Instrument on the Astro-H Observatory

NASA Technical Reports Server (NTRS)

Porter, Frederick; Adams, J. S.; Brown, G. V.; Chervenak, J. A.; Chiao, M. P.; Fujimoto, R.; Ishisaki, Y.; Kelley, R. L.; Kilbourne, C. A.; McCammon, D.;

2011-01-01

The Soft X-ray Spectrometer (SXS) instrument on the Astro-H observatory is based on a 36 pixel x-ray calorimeter array cooled to 50 mK in a sophisticated spaceflight cryostat. The SXS is a true spatial-spectral instrument, where each spatially discrete pixel functions as a high-resolution spectrometer. Here we discuss the SXS detector subsystem that includes the detector array, the anticoincidence detector, the first stage amplifiers, the thermal and mechanical staging of the detector, and the cryogenic bias electronics. The design of the SXS detector subsystem has significant heritage from the Suzaku/XRS instrument but has some important modifications that increase performance margins and simplify the focal plane assembly. Notable improvements include x-ray absorbers with significantly lower heat capacity, improved load resistors, improved thermometry, and a decreased sensitivity to thermal radiation. These modifications have yielded an energy resolution of 3.5-4.0 eV FWHM at 6 keV for representative devices in the laboratory, giving considerable margin against the 7 eV instrument requirement. We expect similar performance in flight

The AXAF/XRS ADR - Engineering model

NASA Technical Reports Server (NTRS)

Serlemitsos, Aristides T.; Sansebastian, Marcelino; Kunes, Evan S.

1991-01-01

A spaceworthy Adiabatic Demagnetization Refrigerator is under development at Goddard Space Flight Center as part of the X-Ray Spectrometer (XRS), an instrument on the Advanced X-ray Astrophysics Facility (AXAF). XRS will employ an array of 32 microcalorimeters capable of detecting X-rays in the energy range of 0.3 - 10 keV. In order to achieve a desired resolution of 12 eV, these detectors must be operated at a temperature of 0.065 - 0.100 K. An ADR must be used to cool these detectors in space. A breadboard model was designed and built less than two years ago, and provided excellent results. We are presently at the development stage of the engineering model. Several changes have been made to the original design in order to improve the efficiency of the ADR, to reduce its weight, and to strengthen the salt pill suspension system so that the ADR can survive launch loads and have low sensitivity to microphonic inputs. We shall report on the results of these changes; what worked and what did not.
Accessing eSDO Solar Image Processing and Visualization through AstroGrid

NASA Astrophysics Data System (ADS)

Auden, E.; Dalla, S.

2008-08-01

The eSDO project is funded by the UK's Science and Technology Facilities Council (STFC) to integrate Solar Dynamics Observatory (SDO) data, algorithms, and visualization tools with the UK's Virtual Observatory project, AstroGrid. In preparation for the SDO launch in January 2009, the eSDO team has developed nine algorithms covering coronal behaviour, feature recognition, and global / local helioseismology. Each of these algorithms has been deployed as an AstroGrid Common Execution Architecture (CEA) application so that they can be included in complex VO workflows. In addition, the PLASTIC-enabled eSDO "Streaming Tool" online movie application allows users to search multi-instrument solar archives through AstroGrid web services and visualise the image data through galleries, an interactive movie viewing applet, and QuickTime movies generated on-the-fly.
Study of the Residual Background Events in Ground Data from the ASTRO-HSXS Microcalorimeter

NASA Technical Reports Server (NTRS)

Kilbourne, Caroline A.; Boyce, Kevin R.; Chiao, M. P.; Eckart, M. E.; Kelley, R. L.; Leutenegger, M. A.; Porter, F. S.; Watanabe, T.; Ishisaki, Y.; Yamada, S.;

2015-01-01

The measured instrumental background of the XRS calorimeter spectrometer of Suzaku had several sources, including primary cosmic rays and secondary particles interacting with the pixels and with the silicon structure of the array. Prior to the launch of Suzaku, several data sets were taken without x-ray illumination to study the characteristics and timing of background signals produced in the array and anti-coincidence detector. Even though the source of the background in the laboratory was different from that in low-earth orbit (muons and environmental gamma-rays on the ground versus Galactic cosmic-ray (GCR) protons and alpha particles in space), the study of correlations and properties of populations of rare events was useful for establishing the preliminary screening parameters needed for selection of good science data. Sea-level muons are singly charged minimum-ionizing particles, like the GCR protons, and thus were good probes of the effectiveness of screening via the signals from the anti-coincidence detector. Here we present the first analysis of the on-ground background of the SXS calorimeter of Astro-H. On XRS, the background prior to screening was completely dominated by coincident events on many pixels resulting from the temperature pulse arising from each large energy deposition (greater than 200 keV) into the silicon frame around the array. The improved heat-sinking of the SXS array compared with XRS eliminated these thermal disturbances, greatly reducing the measured count rate in the absence of illumination. The removal of these events has made it easier to study the nature of the residual background and to look for additional event populations. We compare the SXS residual background to that measured in equivalent ground data for XRS and discuss these preliminary results.

The ASTRO-H X-ray astronomy satellite

NASA Astrophysics Data System (ADS)

Takahashi, Tadayuki; Mitsuda, Kazuhisa; Kelley, Richard; Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie; Allen, Steve; Anabuki, Naohisa; Angelini, Lorella; Arnaud, Keith; Asai, Makoto; Audard, Marc; Awaki, Hisamitsu; Azzarello, Philipp; Baluta, Chris; Bamba, Aya; Bando, Nobutaka; Bautz, Marshall; Bialas, Thomas; Blandford, Roger D.; Boyce, Kevin; Brenneman, Laura; Brown, Gregory; Cackett, Ed; Canavan, Edgar; Chernyakova, Maria; Chiao, Meng; Coppi, Paolo; Costantini, Elisa; de Plaa, Jelle; den Herder, Jan-Willem; DiPirro, Michael; Done, Chris; Dotani, Tadayasu; Doty, John; Ebisawa, Ken; Enoto, Teruaki; Ezoe, Yuichiro; Fabian, Andrew; Ferrigno, Carlo; Foster, Adam; Fujimoto, Ryuichi; Fukazawa, Yasushi; Funk, Stefan; Furuzawa, Akihiro; Galeazzi, Massimiliano; Gallo, Luigi; Gandhi, Poshak; Gilmore, Kirk; Guainazzi, Matteo; Haas, Daniel; Haba, Yoshito; Hamaguchi, Kenji; Harayama, Atsushi; Hatsukade, Isamu; Hayashi, Katsuhiro; Hayashi, Takayuki; Hayashida, Kiyoshi; Hiraga, Junko; Hirose, Kazuyuki; Hornschemeier, Ann; Hoshino, Akio; Hughes, John; Hwang, Una; Iizuka, Ryo; Inoue, Yoshiyuki; Ishibashi, Kazunori; Ishida, Manabu; Ishikawa, Kumi; Ishimura, Kosei; Ishisaki, Yoshitaka; Itoh, Masayuki; Iwata, Naoko; Iyomoto, Naoko; Jewell, Chris; Kaastra, Jelle; Kallman, Timothy; Kamae, Tuneyoshi; Kataoka, Jun; Katsuda, Satoru; Katsuta, Junichiro; Kawaharada, Madoka; Kawai, Nobuyuki; Kawano, Taro; Kawasaki, Shigeo; Khangaluyan, Dmitry; Kilbourne, Caroline; Kimball, Mark; Kimura, Masashi; Kitamoto, Shunji; Kitayama, Tetsu; Kohmura, Takayoshi; Kokubun, Motohide; Konami, Saori; Kosaka, Tatsuro; Koujelev, Alexander; Koyama, Katsuji; Krimm, Hans; Kubota, Aya; Kunieda, Hideyo; LaMassa, Stephanie; Laurent, Philippe; Lebrun, François; Leutenegger, Maurice; Limousin, Olivier; Loewenstein, Michael; Long, Knox; Lumb, David; Madejski, Grzegorz; Maeda, Yoshitomo; Makishima, Kazuo; Markevitch, Maxim; Masters, Candace; Matsumoto, Hironori; Matsushita, Kyoko; McCammon, Dan; McGuinness, Daniel; McNamara, Brian; Miko, Joseph; Miller, Jon; Miller, Eric; Mineshige, Shin; Minesugi, Kenji; Mitsuishi, Ikuyuki; Miyazawa, Takuya; Mizuno, Tsunefumi; Mori, Koji; Mori, Hideyuki; Moroso, Franco; Muench, Theodore; Mukai, Koji; Murakami, Hiroshi; Murakami, Toshio; Mushotzky, Richard; Nagano, Housei; Nagino, Ryo; Nakagawa, Takao; Nakajima, Hiroshi; Nakamori, Takeshi; Nakashima, Shinya; Nakazawa, Kazuhiro; Namba, Yoshiharu; Natsukari, Chikara; Nishioka, Yusuke; Nobukawa, Masayoshi; Noda, Hirofumi; Nomachi, Masaharu; O'Dell, Steve; Odaka, Hirokazu; Ogawa, Hiroyuki; Ogawa, Mina; Ogi, Keiji; Ohashi, Takaya; Ohno, Masanori; Ohta, Masayuki; Okajima, Takashi; Okazaki, Tsuyoshi; Ota, Naomi; Ozaki, Masanobu; Paerels, Frits; Paltani, Stéphane; Parmar, Arvind; Petre, Robert; Pinto, Ciro; Pohl, Martin; Pontius, James; Porter, F. S.; Pottschmidt, Katja; Ramsey, Brian; Reis, Rubens; Reynolds, Christopher; Ricci, Claudio; Russell, Helena; Safi-Harb, Samar; Saito, Shinya; Sakai, Shin-ichiro; Sameshima, Hiroaki; Sato, Kosuke; Sato, Rie; Sato, Goro; Sawada, Makoto; Serlemitsos, Peter; Seta, Hiromi; Shibano, Yasuko; Shida, Maki; Shimada, Takanobu; Shirron, Peter; Simionescu, Aurora; Simmons, Cynthia; Smith, Randall; Sneiderman, Gary; Soong, Yang; Stawarz, Lukasz; Sugawara, Yasuharu; Sugita, Satoshi; Szymkowiak, Andrew; Tajima, Hiroyasu; Takahashi, Hiroaki; Takahashi, Hiromitsu; Takeda, Shin-ichiro; Takei, Yoh; Tamagawa, Toru; Tamura, Keisuke; Tamura, Takayuki; Tanaka, Takaaki; Tanaka, Yasuyuki; Tanaka, Yasuo; Tashiro, Makoto; Tawara, Yuzuru; Terada, Yukikatsu; Terashima, Yuichi; Tombesi, Francesco; Tomida, Hiroshi; Tsuboi, Yoko; Tsujimoto, Masahiro; Tsunemi, Hiroshi; Tsuru, Takeshi; Uchida, Hiroyuki; Uchiyama, Hideki; Uchiyama, Yasunobu; Ueda, Yoshihiro; Ueda, Shutaro; Ueno, Shiro; Uno, Shinichiro; Urry, Meg; Ursino, Eugenio; de Vries, Cor; Wada, Atsushi; Watanabe, Shin; Watanabe, Tomomi; Werner, Norbert; White, Nicholas; Wilkins, Dan; Yamada, Shinya; Yamada, Takahiro; Yamaguchi, Hiroya; Yamaoka, Kazutaka; Yamasaki, Noriko; Yamauchi, Makoto; Yamauchi, Shigeo; Yaqoob, Tahir; Yatsu, Yoichi; Yonetoku, Daisuke; Yoshida, Atsumasa; Yuasa, Takayuki; Zhuravleva, Irina; Zoghbi, Abderahmen; ZuHone, John

2014-07-01

The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions developed by the Institute of Space and Astronautical Science (ISAS), with a planned launch in 2015. The ASTRO-H mission is equipped with a suite of sensitive instruments with the highest energy resolution ever achieved at E > 3 keV and a wide energy range spanning four decades in energy from soft X-rays to gamma-rays. The simultaneous broad band pass, coupled with the high spectral resolution of ΔE <= 7 eV of the micro-calorimeter, will enable a wide variety of important science themes to be pursued. ASTRO-H is expected to provide breakthrough results in scientific areas as diverse as the large-scale structure of the Universe and its evolution, the behavior of matter in the gravitational strong field regime, the physical conditions in sites of cosmic-ray acceleration, and the distribution of dark matter in galaxy clusters at different redshifts.
The AstroSat Production Line: From AstroSat 100 to AstroSat 1000

NASA Astrophysics Data System (ADS)

Maliet, E.; Pawlak, D.; Koeck, C.; Beaufumé, E.

2008-08-01

From the late 90s onward, Astrium Satellites has developed and improved several classes of high resolution optical Earth Observation satellites. The resulting product line ranges from micro-satellites (about 120 kg) type to the large satellites (in the range of 1 200 kg). They all make uses of state of the art technologies for optical payloads, as well as for avionics. Several classes of platforms have thus been defined and standardised: AstroSat 100 for satellites up to 150 kg, allowing affordable but fully operational missions, AstroSat 500 for satellites up to 800 kg, allowing complex high resolution missions, and AstroSat 1000 for satellites up to 1 200 kg, providing very high resolution and outstanding imaging and agility capabilities. A new class, AstroSat 250, has been developed by Astrium Satellites, and is now proposed, offering a state-of-the-art 3-axis agile platform for high- resolution missions, with a launch mass below 550 kg. The Astrosat platforms rely on a centralised architecture avionics based on an innovative AOCS hybridising of measurements from GPS, stellar sensors and inertial reference unit. Operational safety has been emphasised through thruster free safe modes. All optical payloads make use of all Silicon Carbide (SiC) telescopes. High performance and low consumption linear CCD arrays provide state of the art images. The satellites are designed for simple flight operations, large data collection capability, and large versatility of payload and missions. They are adaptable to a large range of performances. Astrium satellites have already been selected by various customers worldwide.
Astro Camp

NASA Image and Video Library

2012-06-12

Each year, more than 400 Mississippi and out-of-state youths visit Stennis Space Center for weeklong Astro Camp activities. Astro Camp sessions are for children ages 7-12. The focus for 2012 Astro Camp participants was on 'What's Next for NASA! Moon, Mars, Asteroids and Beyond.'
Mechanisms underlying radiosensitivity : iIvestigations in xrs-5, an X-ray sensitive hamster cell line

NASA Astrophysics Data System (ADS)

Johnston, Peter James

The damage caused to cells by ionising radiation is believed to center on damage to the DNA. In particular, the induction of DNA double strand breaks (DSB) have been implicated in biological end-points such as cell killing and the formation of chromosomal aberrations. The xrs-5 cell line is a mutant Chinese hamster ovary fibroblast (CHO-K1) mutant which exhibits sensitivity to ionising radiation and a number of other DNA damaging agents. This mutation, postulated to involve the hamster homologue of the human XRCC5 gene, is believed to be involved in the repair of the DSB. In addition, there are constitutive differences between the wild type and xrs cells involving the structure and function of the nucleus and higher order chromatin structures. The aims of this thesis were to study further the xrs-5 cell line and its response to DNA damage and to investigate the possible link between chromatin structure and DSB repair. By the examination of the response of xrs-5 cells to a number of DNA damaging agents and potential modulators of this response using the cytokinesis block micronucleus assay [Fenech and Morley, 1985] a possible cell cycle defect was identified in addition to elevated levels of chromosomal damage. Xrs-5 cells appeared to be partially defective in the cell cycle checkpoints involving the passage from G2 phase to mitosis. By the use of a modified neutral filter elution procedure variations in the repair of DSB were observed between xrs-5 and CHO. Conventional neutral filter elution requires harsh lysis conditions to remove higher order chromatin structures which interfere with the elution of DNA containing DSB. By lysing cells with non-ionic detergent in the presence of 2 M NaC1, histone depleted structures which retain the higher order nuclear matrix organisation, including chromatin loops, can be produced. Elution from these structures will only occur if two or more DSB lie within a single looped domain delineated by points of attachment to the nuclear
The ASTRO-H X-ray Observatory

NASA Astrophysics Data System (ADS)

Takahashi, Tadayuki; Mitsuda, Kazuhisa; Kelley, Richard; Aarts, Henri; Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie; Allen, Steve; Anabuki, Naohisa; Angelini, Lorella; Arnaud, Keith; Asai, Makoto; Audard, Marc; Awaki, Hisamitsu; Azzarello, Philipp; Baluta, Chris; Bamba, Aya; Bando, Nobutaka; Bautz, Mark; Blandford, Roger; Boyce, Kevin; Brown, Greg; Cackett, Ed; Chernyakova, Mara; Coppi, Paolo; Costantini, Elisa; de Plaa, Jelle; den Herder, Jan-Willem; DiPirro, Michael; Done, Chris; Dotani, Tadayasu; Doty, John; Ebisawa, Ken; Eckart, Megan; Enoto, Teruaki; Ezoe, Yuichiro; Fabian, Andrew; Ferrigno, Carlo; Foster, Adam; Fujimoto, Ryuichi; Fukazawa, Yasushi; Funk, Stefan; Furuzawa, Akihiro; Galeazzi, Massimiliano; Gallo, Luigi; Gandhi, Poshak; Gendreau, Keith; Gilmore, Kirk; Haas, Daniel; Haba, Yoshito; Hamaguchi, Kenji; Hatsukade, Isamu; Hayashi, Takayuki; Hayashida, Kiyoshi; Hiraga, Junko; Hirose, Kazuyuki; Hornschemeier, Ann; Hoshino, Akio; Hughes, John; Hwang, Una; Iizuka, Ryo; Inoue, Yoshiyuki; Ishibashi, Kazunori; Ishida, Manabu; Ishimura, Kosei; Ishisaki, Yoshitaka; Ito, Masayuki; Iwata, Naoko; Iyomoto, Naoko; Kaastra, Jelle; Kallman, Timothy; Kamae, Tuneyoshi; Kataoka, Jun; Katsuda, Satoru; Kawahara, Hajime; Kawaharada, Madoka; Kawai, Nobuyuki; Kawasaki, Shigeo; Khangaluyan, Dmitry; Kilbourne, Caroline; Kimura, Masashi; Kinugasa, Kenzo; Kitamoto, Shunji; Kitayama, Tetsu; Kohmura, Takayoshi; Kokubun, Motohide; Kosaka, Tatsuro; Koujelev, Alex; Koyama, Katsuji; Krimm, Hans; Kubota, Aya; Kunieda, Hideyo; LaMassa, Stephanie; Laurent, Philippe; Lebrun, Francois; Leutenegger, Maurice; Limousin, Olivier; Loewenstein, Michael; Long, Knox; Lumb, David; Madejski, Grzegorz; Maeda, Yoshitomo; Makishima, Kazuo; Marchand, Genevieve; Markevitch, Maxim; Matsumoto, Hironori; Matsushita, Kyoko; McCammon, Dan; McNamara, Brian; Miller, Jon; Miller, Eric; Mineshige, Shin; Minesugi, Kenji; Mitsuishi, Ikuyuki; Miyazawa, Takuya; Mizuno, Tsunefumi; Mori, Hideyuki; Mori, Koji; Mukai, Koji; Murakami, Toshio; Murakami, Hiroshi; Mushotzky, Richard; Nagano, Hosei; Nagino, Ryo; Nakagawa, Takao; Nakajima, Hiroshi; Nakamori, Takeshi; Nakazawa, Kazuhiro; Namba, Yoshiharu; Natsukari, Chikara; Nishioka, Yusuke; Nobukawa, Masayoshi; Nomachi, Masaharu; O'Dell, Steve; Odaka, Hirokazu; Ogawa, Hiroyuki; Ogawa, Mina; Ogi, Keiji; Ohashi, Takaya; Ohno, Masanori; Ohta, Masayuki; Okajima, Takashi; Okamoto, Atsushi; Okazaki, Tsuyoshi; Ota, Naomi; Ozaki, Masanobu; Paerels, Fritzs; Paltani, Stéphane; Parmar, Arvind; Petre, Robert; Pohl, Martin; Porter, F. Scott; Ramsey, Brian; Reis, Rubens; Reynolds, Christopher; Russell, Helen; Safi-Harb, Samar; Sakai, Shin-ichiro; Sameshima, Hiroaki; Sanders, Jeremy; Sato, Goro; Sato, Rie; Sato, Yohichi; Sato, Kosuke; Sawada, Makoto; Serlemitsos, Peter; Seta, Hiromi; Shibano, Yasuko; Shida, Maki; Shimada, Takanobu; Shinozaki, Keisuke; Shirron, Peter; Simionescu, Aurora; Simmons, Cynthia; Smith, Randall; Sneiderman, Gary; Soong, Yang; Stawarz, Lukasz; Sugawara, Yasuharu; Sugita, Hiroyuki; Sugita, Satoshi; Szymkowiak, Andrew; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takeda, Shin-ichiro; Takei, Yoh; Tamagawa, Toru; Tamura, Takayuki; Tamura, Keisuke; Tanaka, Takaaki; Tanaka, Yasuo; Tashiro, Makoto; Tawara, Yuzuru; Terada, Yukikatsu; Terashima, Yuichi; Tombesi, Francesco; Tomida, Hiroshi; Tsuboi, Yohko; Tsujimoto, Masahiro; Tsunemi, Hiroshi; Tsuru, Takeshi; Uchida, Hiroyuki; Uchiyama, Yasunobu; Uchiyama, Hideki; Ueda, Yoshihiro; Ueno, Shiro; Uno, Shinichiro; Urry, Meg; Ursino, Eugenio; de Vries, Cor; Wada, Atsushi; Watanabe, Shin; Werner, Norbert; White, Nicholas; Yamada, Takahiro; Yamada, Shinya; Yamaguchi, Hiroya; Yamasaki, Noriko; Yamauchi, Shigeo; Yamauchi, Makoto; Yatsu, Yoichi; Yonetoku, Daisuke; Yoshida, Atsumasa; Yuasa, Takayuki

2012-09-01

The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions initiated by the Institute of Space and Astronautical Science (ISAS). ASTRO-H will investigate the physics of the highenergy universe via a suite of four instruments, covering a very wide energy range, from 0.3 keV to 600 keV. These instruments include a high-resolution, high-throughput spectrometer sensitive over 0.3-12 keV with high spectral resolution of ΔE ≦ 7 eV, enabled by a micro-calorimeter array located in the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers covering 5-80 keV, located in the focal plane of multilayer-coated, focusing hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4-12 keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the 40-600 keV band. The simultaneous broad bandpass, coupled with high spectral resolution, will enable the pursuit of a wide variety of important science themes.
Alignment monitoring system for ASTRO-H

NASA Astrophysics Data System (ADS)

Grandmont, Frédéric; Dupont, Fabien; Moreau, Louis; Larouche, Martin; Bibeau, Louis-Philippe; Laplante, Sylvio

2017-11-01

High Energy Astrophysics (HEA) encompasses a broad range of astrophysical science, with sources that include stars and stellar clusters, compact objects (black holes, neutron stars, and white dwarfs), supernova remnants, the interstellar medium, galaxies and clusters of galaxies, Active Galactic Nuclei (AGN), and gamma ray bursters, as well as a variety of fundamental physical processes. The physics involved includes extremes of gravity, density and magnetic field and is often inaccessible via any other waveband. HEA investigates and answers crucial questions in all fields of contemporary astrophysics. Unlike the focusing of radio and optical light, X-rays are brought to focus through shallow, grazing incident angles. The analogy of skimming a stone across a pond is appropriate in describing how X-rays are focused. The higher the energy of the X-ray photon the shallower the incident angle must be, thereby introducing the requirement of longer focal lengths for focusing high-energy X-rays (E > 10 keV). This technical challenge has hindered scientific advancement in the high-energy regime, while at lower X-ray energies the community has prospered immensely with spectacular data from focusing observatories like XMM-Newton, Chandra, and Suzaku. Now, with ASTRO-H, the community will reap similar rewards from the tremendous improvement in spatial and spectral resolution at high energies. ASTRO-H is a JAXA mission. More information can be found on the ASTRO-H web site [1]. Because of the grazing-angle optics, high-energy X-ray instruments have a long focal length. The Hard X-ray Imager (HXI) of ASTRO-H has its detector housed in a boom that will extend by about 6 m in orbit so that a focal length of 12 m can be achieved for that instrument. This long structure will inevitably oscillate and flex, especially when passing across the orbital day/night boundary. In order to retain the essential imaging resolution, it is important that the boom has a metrology system that
High Resolution, Non-Dispersive X-Ray Calorimeter Spectrometers on EBITs and Orbiting Observatories

NASA Technical Reports Server (NTRS)

Porter, Frederick S.

2010-01-01

X-ray spectroscopy is the primary tool for performing atomic physics with Electron beam ion trap (EBITs). X-ray instruments have generally fallen into two general categories, 1) dispersive instruments with very high spectral resolving powers but limited spectral range, limited count rates, and require an entrance slit, generally, for EBITs, defined by the electron beam itself, and 2) non-dispersive solid-state detectors with much lower spectral resolving powers but that have a broad dynamic range, high count rate ability and do not require a slit. Both of these approaches have compromises that limit the type and efficiency of measurements that can be performed. In 1984 NASA initiated a program to produce a non-dispersive instrument with high spectral resolving power for x-ray astrophysics based on the cryogenic x-ray calorimeter. This program produced the XRS non-dispersive spectrometers on the Astro-E, Astro-E2 (Suzaku) orbiting observatories, the SXS instrument on the Astro-H observatory, and the planned XMS instrument on the International X-ray Observatory. Complimenting these spaceflight programs, a permanent high-resolution x-ray calorimeter spectrometer, the XRS/EBIT, was installed on the LLNL EBIT in 2000. This unique instrument was upgraded to a spectral resolving power of 1000 at 6 keV in 2003 and replaced by a nearly autonomous production-class spectrometer, the EBIT Calorimeter Spectrometer (ECS), in 2007. The ECS spectrometer has a simultaneous bandpass from 0.07 to over 100 keV with a spectral resolving power of 1300 at 6 keV with unit quantum efficiency, and 1900 at 60 keV with a quantum efficiency of 30%. X-ray calorimeters are event based, single photon spectrometers with event time tagging to better than 10 us. We are currently developing a follow-on instrument based on a newer generation of x-ray calorimeters with a spectral resolving power of 3000 at 6 keV, and improved timing and measurement cadence. The unique capabilities of the x
AstroGrid: the UK's Virtual Observatory Initiative

NASA Astrophysics Data System (ADS)

Mann, Robert G.; Astrogrid Consortium; Lawrence, Andy; Davenhall, Clive; Mann, Bob; McMahon, Richard; Irwin, Mike; Walton, Nic; Rixon, Guy; Watson, Mike; Osborne, Julian; Page, Clive; Allan, Peter; Giaretta, David; Perry, Chris; Pike, Dave; Sherman, John; Murtagh, Fionn; Harra, Louise; Bentley, Bob; Mason, Keith; Garrington, Simon

AstroGrid is the UK's Virtual Observatory (VO) initiative. It brings together the principal astronomical data centres in the UK, and has been funded to the tune of ˜pounds 5M over the next three years, via PPARC, as part of the UK e--science programme. Its twin goals are the provision of the infrastructure and tools for the federation and exploitation of large astronomical (X-ray to radio), solar and space plasma physics datasets, and the delivery of federations of current datasets for its user communities to exploit using those tools. Whilst AstroGrid's work will be centred on existing and future (e.g. VISTA) UK datasets, it will seek solutions to generic VO problems and will contribute to the developing international virtual observatory framework: AstroGrid is a member of the EU-funded Astrophysical Virtual Observatory project, has close links to a second EU Grid initiative, the European Grid of Solar Observations (EGSO), and will seek an active role in the development of the common standards on which the international virtual observatory will rely. In this paper we shall primarily describe the concrete plans for AstroGrid's one-year Phase A study, which will centre on: (i) the definition of detailed science requirements through community consultation; (ii) the undertaking of a ``functionality market survey" to test the utility of existing technologies for the VO; and (iii) a pilot programme of database federations, each addressing different aspects of the general database federation problem. Further information on AstroGrid can be found at AstroGrid .
Removing Spectral Diagnostics of Galactic and Stellar X-Ray Emission from Charged Exchange Recombination

NASA Technical Reports Server (NTRS)

Wargelin, Brad

2004-01-01

Our research uses the electron beam ion trap (EBIT) at the Lawrence Livermore National Laboratory to study X-ray emission from the charge exchange (CX) of highly charged ions with neutral gases. The resulting data help to fill a void in existing experimental and theoretical understanding of this atomic physics process, and are needed to explain all or part of the observed X-ray emission from the soft X-ray background, stellar winds, the Galactic Center and Galactic Ridge, supernova ejecta, and photoionized nebulae. Appreciation of the astrophysical relevance of our work continues to grow with the publication of roughly a dozen papers in the past four years describing Chandra and XMM observations of geocoronal and heliospheric CX emission, the temporal variation of such emission and correlation with X-ray emission enhancements observed by ROSAT, the theoretical spatial distribution of that emission, and CX emission around other stars. A similar number of papers were also published during that time describing CX emission from planets and comets. We expect that the launch of ASTRSE2, with its second-generation XRS microcalo- (with 6-eV resolution), will reveal even more clearly the contributions of CX to astrophysical emission. In our EBIT work we collected CX spectra from such ions as H-like and He-like Ne, Ar, and Fe. Our early measurements were made with a high-purity Ge detector, but during the second year we began operation of the first-generation XRS microcalorimeter (a twin of the XRS on ASTRO-E) and greatly improved the resolution of our measurements from roughly 150 eV (FWHM) with the Ge detectors to 10 eV with the XRS. We found that saturation of the XRS counting apparatus, which we described in our proposal as a potential concern, is not a problem for studying CX. During the course of our research, we expanded the number of injection gases permitted by the LLNL safety team, purchased and eventually operated an atomic H source, and clearly demonstrated the
X-33 XRS-2200 Linear Aerospike Engine Sea Level Plume Radiation

NASA Technical Reports Server (NTRS)

DAgostino, Mark G.; Lee, Young C.; Wang, Ten-See; Turner, Jim (Technical Monitor)

2001-01-01

Wide band plume radiation data were collected during ten sea level tests of a single XRS-2200 engine at the NASA Stennis Space Center in 1999 and 2000. The XRS-2200 is a liquid hydrogen/liquid oxygen fueled, gas generator cycle linear aerospike engine which develops 204,420 lbf thrust at sea level. Instrumentation consisted of six hemispherical radiometers and one narrow view radiometer. Test conditions varied from 100% to 57% power level (PL) and 6.0 to 4.5 oxidizer to fuel (O/F) ratio. Measured radiation rates generally increased with engine chamber pressure and mixture ratio. One hundred percent power level radiation data were compared to predictions made with the FDNS and GASRAD codes. Predicted levels ranged from 42% over to 7% under average test values.
The Astro-H High Resolution Soft X-Ray Spectrometer

NASA Technical Reports Server (NTRS)

Kelley, Richard L.; Akamatsu, Hiroki; Azzarell, Phillip; Bialas, Tom; Boyce, Kevin R.; Brown, Gregory V.; Canavan, Edgar; Chiao, Meng P.; Costantini, Elisa; DiPirro, Michael J.;

2016-01-01

We present the overall design and performance of the Astro-H (Hitomi) Soft X-Ray Spectrometer (SXS). The instrument uses a 36-pixel array of x-ray microcalorimeters at the focus of a grazing-incidence x-ray mirror Soft X-Ray Telescope (SXT) for high-resolution spectroscopy of celestial x-ray sources. The instrument was designed to achieve an energy resolution better than 7 eV over the 0.3-12 keV energy range and operate for more than 3 years in orbit. The actual energy resolution of the instrument is 4-5 eV as demonstrated during extensive ground testing prior to launch and in orbit. The measured mass flow rate of the liquid helium cryogen and initial fill level at launch predict a lifetime of more than 4 years assuming steady mechanical cooler performance. Cryogen-free operation was successfully demonstrated prior to launch. The successful operation of the SXS in orbit, including the first observations of the velocity structure of the Perseus cluster of galaxies, demonstrates the viability and power of this technology as a tool for astrophysics.

The Astro-H high resolution soft x-ray spectrometer

NASA Astrophysics Data System (ADS)

Kelley, Richard L.; Akamatsu, Hiroki; Azzarello, Phillipp; Bialas, Tom; Boyce, Kevin R.; Brown, Gregory V.; Canavan, Edgar; Chiao, Meng P.; Costantini, Elisa; DiPirro, Michael J.; Eckart, Megan E.; Ezoe, Yuichiro; Fujimoto, Ryuichi; Haas, Daniel; den Herder, Jan-Willem; Hoshino, Akio; Ishikawa, Kumi; Ishisaki, Yoshitaka; Iyomoto, Naoko; Kilbourne, Caroline A.; Kimball, Mark O.; Kitamoto, Shunji; Konami, Saori; Koyama, Shu; Leutenegger, Maurice A.; McCammon, Dan; Mitsuda, Kazuhisa; Mitsuishi, Ikuyuki; Moseley, Harvey; Murakami, Hiroshi; Murakami, Masahide; Noda, Hirofumi; Ogawa, Mina; Ohashi, Takaya; Okamoto, Atsushi; Ota, Naomi; Paltani, Stéphane; Porter, F. S.; Sakai, Kazuhiro; Sato, Kosuke; Sato, Yohichi; Sawada, Makoto; Seta, Hiromi; Shinozaki, Keisuke; Shirron, Peter J.; Sneiderman, Gary A.; Sugita, Hiroyuki; Szymkowiak, Andrew E.; Takei, Yoh; Tamagawa, Toru; Tashiro, Makoto; Terada, Yukikatsu; Tsujimoto, Masahiro; de Vries, Cor P.; Yamada, Shinya; Yamasaki, Noriko Y.; Yatsu, Yoichi

2016-07-01

We present the overall design and performance of the Astro-H (Hitomi) Soft X-Ray Spectrometer (SXS). The instrument uses a 36-pixel array of x-ray microcalorimeters at the focus of a grazing-incidence x-ray mirror Soft X-Ray Telescope (SXT) for high-resolution spectroscopy of celestial x-ray sources. The instrument was designed to achieve an energy resolution better than 7 eV over the 0.3-12 keV energy range and operate for more than 3 years in orbit. The actual energy resolution of the instrument is 4-5 eV as demonstrated during extensive ground testing prior to launch and in orbit. The measured mass flow rate of the liquid helium cryogen and initial fill level at launch predict a lifetime of more than 4 years assuming steady mechanical cooler performance. Cryogen-free operation was successfully demonstrated prior to launch. The successful operation of the SXS in orbit, including the first observations of the velocity structure of the Perseus cluster of galaxies, demonstrates the viability and power of this technology as a tool for astrophysics.
SPIKE: Application for ASTRO-D mission planning

NASA Technical Reports Server (NTRS)

Isobe, T.; Johnston, M.; Morgan, E.; Clark, G.

1992-01-01

SPIKE is a mission planning software system developed by a team of programmers at the STScI for use with the Hubble Space Telescope (HST). SPIKE has been developed for the purpose of automating observatory scheduling to increase the effective utilization and ultimately, scientific return from orbiting telescopes. High-level scheduling strategies using both rule-based and neural network approaches have been incorporated. Graphical displays of activities, constraints, and schedules are an important feature of the system. Although SPIKE was originally developed for the HST, it can be used for other astronomy missions including ground-based observatories. One of the missions that has decided to use SPIKE is ASTRO-D, a Japanese X-ray satellite for which the U.S. is providing a part of the scientific payload. Scheduled to fly in Feb. 1993, its four telescopes will focus X-rays over a wide energy range onto CCD's and imaging gas proportional counters. ASTRO-D will be the first X-ray imaging mission operating over the 0.5-12 keV band with high energy resolution. This combination of capabilities will enable a varied and exciting program of astronomical research to be carried out. ASTRO-D is expected to observe 5 to 20 objects per day and a total of several thousands per year. This requires the implementation of an efficient planning and scheduling system which SPIKE can provide. Although the version of SPIKE that will be used for ASTRO-D mission is almost identical to that used for the HST, there are a few differences. For example, ASTRO-D will use two ground stations for data downlinks, instead of the TDRSS system for data transmission. As a consequence ASTRO-D is constrained by limited on-board data storage capacity to schedule high data-rate observations during periods of frequent high bit rate observations accordingly. We will demonstrate the ASTRO-D version of SPIKE to show what SPIKE can provide and how efficiently it creates an observational schedule.
Forkhead-Associated Domain of Yeast Xrs2, a Homolog of Human Nbs1, Promotes Nonhomologous End Joining Through Interaction With a Ligase IV Partner Protein, Lif1

PubMed Central

Matsuzaki, Kenichiro; Shinohara, Akira; Shinohara, Miki

2008-01-01

DNA double-strand breaks (DSB) are repaired through two different pathways, homologous recombination (HR) and nonhomologous end joining (NHEJ). Yeast Xrs2, a homolog of human Nbs1, is a component of the Mre11-Rad50-Xrs2 (MRX) complex required for both HR and NHEJ. Previous studies showed that the N-terminal forkhead-associated (FHA) domain of Xrs2/Nbs1 in yeast is not involved in HR, but is likely to be in NHEJ. In this study, we showed that the FHA domain of Xrs2 plays a critical role in efficient DSB repair by NHEJ. The FHA domain of Xrs2 specifically interacts with Lif1, a component of the ligase IV complex, Dnl4-Nej1-Lif1 (DNL). Lif1, which is phosphorylated in vivo, contains two Xrs2-binding regions. Serine 383 of Lif1 plays an important role in the interaction with Xrs2 as well as in NHEJ. Interestingly, the phospho-mimetic substitutions of serine 383 enhance the NHEJ activity of Lif1. Our results suggest that the phosphorylation of Lif1 at serine 383 is recognized by the Xrs2 FHA domain, which in turn may promote recruitment of the DNL complex to DSB for NHEJ. The interaction between Xrs2 and Lif1 through the FHA domain is conserved in humans; the FHA domain Nbs1 interacts with Xrcc4, a Lif1 homolog of human. PMID:18458108
Common observations of solar X-rays from SPHINX/CORONAS-PHOTON and XRS/MESSENGER

NASA Astrophysics Data System (ADS)

Kepa, Anna; Sylwester, Janusz; Sylwester, Barbara; Siarkowski, Marek; Mrozek, Tomasz; Gryciuk, Magdalena; Phillips, Kenneth

SphinX was a soft X-ray spectrophotometer constructed in the Space Research Centre of Polish Academy of Sciences. The instrument was launched on 30 January 2009 aboard CORONAS-PHOTON satellite as a part of TESIS instrument package. SphinX measured total solar X-ray flux in the energy range from 1 to 15 keV during the period of very low solar activity from 20 February to 29 November 2009. For these times the solar detector (X-ray Spectrometer - XRS) onboard MESSENGER also observed the solar X-rays from a different vantage point. XRS measured the radiation in similar energy range. We present results of the comparison of observations from both instruments and show the preliminary results of physical analysis of spectra for selected flares.
The High Resolution Microcalorimeter Soft X-Ray Spectrometer for the Astro-H Mission

NASA Technical Reports Server (NTRS)

Kelley, Richard L.; Mitsuda, Kazuhisa; den Herder, Jan-Willem A.; Aarts, Henri J. M.; Azzarello, Philipp; Boyce, Kevin R.; Brown, Gregory V.; Chiao, Meng P.; de Vries, Cor P.; DiPirro, Michael J.;

2012-01-01

We are developing the Soft X-Ray Spectrometer for the JAXA Astro-H mission. The instrument features a 5 eV, 36-pixel array of micro calorimeters designed for high spectral resolution from 0.3-12 keV at the focus of an x-ray mirror, providing a field of view of3 x 3 arcmin. The principal components of the spectrometer are the microcalorimeter detector system, a 3-stage ADR and dewar. The dewar is a long-life, hybrid design with a superfluid He cryostat, Joule-Thomson cooler, and Stirling coolers. We describe the present design of the SXS instrument and initial engineering model test results.

Astro-1 Image Taken by Ultraviolet Imaging Telescope

NASA Technical Reports Server (NTRS)

1990-01-01

This image shows a part of the Cygnus loop supernova remnant, taken by the Ultraviolet Imaging Telescope (UIT) on the Astro Observatory during the Astro-1 mission (STS-35) on December 5, 1990. Pictured is a portion of the huge Cygnus loop, an array of interstellar gas clouds that have been blasted by a 900,000 mile per hour shock wave from a prehistoric stellar explosion, which occurred about 20,000 years ago, known as supernova. With ultraviolet and x-rays, astronomers can see emissions from extremely hot gases, intense magnetic fields, and other high-energy phenomena that more faintly appear in visible and infrared light or in radio waves that are crucial to deepening the understanding of the universe. The Astro Observatory was designed to explore the universe by observing and measuring the ultraviolet radiation from celestial objects. Three instruments make up the Astro Observatory: The Hopkins Ultraviolet Telescope (HUT), the Ultraviolet Imaging Telescope (UIT), and the Wisconsin Ultraviolet Photo-Polarimetry Experiment (WUPPE). The Marshall Space Flight Center had managment responsibilities for the Astro-1 mission. The Astro-1 Observatory was launched aboard the Space Shuttle Orbiter Columbia (STS-35) on December 2, 1990.
The ASTRO-1 preliminary design review coupled load analysis

NASA Technical Reports Server (NTRS)

Mcghee, D. S.

1984-01-01

Results of the ASTRO-1 preliminary design review coupled loads analysis are presented. The M6.0Y Generic Shuttle mathematical models were used. Internal accelerations, interface forces, relative displacements, and net e.g., accelerations were recovered for two ASTRO-1 payloads in a tandem configuration. Twenty-seven load cases were computed and summarized. Load exceedences were found and recommendations made.
Astro-geodetic platform for high accuracy geoid determinat ion

NASA Astrophysics Data System (ADS)

Bǎdescu, Octavian; Nedelcu, Dan Alin; Cǎlin, Alexandru; Dumitru, Paul Daniel; Cǎlin, Lavinia A.; Popescu, Marcel

The paper presents first technical realizations of a mobile platform for vertical deviation determination at a satisfactory precision and low cost. The conception of the platform was made in the framework of a project regarding CCD astro-geodetic vertical deviation for geoid determination or geoid modeling. The project with the acronym A-GEO represents a collaboration between Technical University of Civil Engineering Bucharest - Faculty of Geodesy, (TUCEB-FG), Astronomical Institute of the Romanian academy (AIRA), and a private partner GeoGIS Proiect S.R.L. The paper presents some hardware and software aspects regarding design, development, and automation of the platform, based on an electro-optical geodetic instrument, CCD observations and satellite time synchronization for astro-geodetic measurements.
Astro Camp Plus

NASA Image and Video Library

2006-06-19

Stennis Space Center's new Astro Camp Plus camp kicked off June 19 for teens ages 13-15. The new camp delves more deeply into the science, math and technology concepts introduced in the center's popular Astro Camp series. Campers including Jasmyne White (left) and Dana Yingst, both of Slidell, La., learn how NASA uses 'podcasting' to broadcast video, and made their own podcasts.

Astro Camp Plus

NASA Technical Reports Server (NTRS)

2006-01-01

Stennis Space Center's new Astro Camp Plus camp kicked off June 19 for teens ages 13-15. The new camp delves more deeply into the science, math and technology concepts introduced in the center's popular Astro Camp series. Campers including Jasmyne White (left) and Dana Yingst, both of Slidell, La., learn how NASA uses 'podcasting' to broadcast video, and made their own podcasts.
AstroGrid-D: Grid technology for astronomical science

NASA Astrophysics Data System (ADS)

Enke, Harry; Steinmetz, Matthias; Adorf, Hans-Martin; Beck-Ratzka, Alexander; Breitling, Frank; Brüsemeister, Thomas; Carlson, Arthur; Ensslin, Torsten; Högqvist, Mikael; Nickelt, Iliya; Radke, Thomas; Reinefeld, Alexander; Reiser, Angelika; Scholl, Tobias; Spurzem, Rainer; Steinacker, Jürgen; Voges, Wolfgang; Wambsganß, Joachim; White, Steve

2011-02-01

We present status and results of AstroGrid-D, a joint effort of astrophysicists and computer scientists to employ grid technology for scientific applications. AstroGrid-D provides access to a network of distributed machines with a set of commands as well as software interfaces. It allows simple use of computer and storage facilities and to schedule or monitor compute tasks and data management. It is based on the Globus Toolkit middleware (GT4). Chapter 1 describes the context which led to the demand for advanced software solutions in Astrophysics, and we state the goals of the project. We then present characteristic astrophysical applications that have been implemented on AstroGrid-D in chapter 2. We describe simulations of different complexity, compute-intensive calculations running on multiple sites (Section 2.1), and advanced applications for specific scientific purposes (Section 2.2), such as a connection to robotic telescopes (Section 2.2.3). We can show from these examples how grid execution improves e.g. the scientific workflow. Chapter 3 explains the software tools and services that we adapted or newly developed. Section 3.1 is focused on the administrative aspects of the infrastructure, to manage users and monitor activity. Section 3.2 characterises the central components of our architecture: The AstroGrid-D information service to collect and store metadata, a file management system, the data management system, and a job manager for automatic submission of compute tasks. We summarise the successfully established infrastructure in chapter 4, concluding with our future plans to establish AstroGrid-D as a platform of modern e-Astronomy.
The development of high resolution silicon x-ray microcalorimeters

NASA Astrophysics Data System (ADS)

Porter, F. S.; Kelley, R. L.; Kilbourne, C. A.

2005-12-01

Recently we have produced x-ray microcalorimeters with resolving powers approaching 2000 at 5.9 keV using a spare XRS microcalorimeter array. We attached 400 um square, 8 um thick HgTe absorbers using a variety of attachment methods to an XRS array and ran the detector array at temperatures between 40 and 60 mK. The best results were for absorbers attached using the standard XRS absorber-pixel thermal isolation scheme utilizing SU8 polymer tubes. In this scenario we achieved a resolution of 3.2 eV FWHM at 5.9 keV. Substituting a silicon spacer for the SU8 tubes also yielded sub-4eV results. In contrast, absorbers attached directly to the thermistor produced significant position dependence and thus degraded resolution. Finally, we tested standard 640um-square XRS detectors at reduced bias power at 50mK and achieved a resolution of 3.7eV, a 50% improvement over the XRS flight instrument. Implanted silicon microcalorimeters are a mature flight-qualified technology that still has a substantial phase space for future development. We will discuss these new high resolution results, the various absorber attachment schemes, planned future improvements, and, finally, their relevance to future high resolution x-ray spectrometers including Constellation-X.
Astro Tourism in Chile | CTIO

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Program PIA Program GO-FAAR Program Other Opportunities Tourism Visits to Tololo Astro tourism in Chile Tourism in Chile Information for travelers Visit Tololo Media Relations News Press Release Publications â¹âº You are here CTIO Home Â» Outreach Â» Tourism Â» Astro Tourism in Chile Astro Tourism in
Astro Camp 2000 Rocketry Exercise

NASA Image and Video Library

2000-06-23

Children at Astro Camp at the John C. Stennis Space Center in Hancock County, Miss., launch rockets as one of their activities in the weeklong camp. Each week during the summer, approximately 30 children ages 9-12 from across Mississippi and Louisiana spend a week learning about space flight. Astro Camp Saturday offers a condensed version of Astro Camp on the third Saturday of each month from January through May 2001.
An introduction to the Astro Edge solar array

NASA Technical Reports Server (NTRS)

Spence, B. R.; Marks, G. W.

1994-01-01

The Astro Edge solar array is a new and innovative low concentrator power generating system which has been developed for applications requiring high specific power, high stiffness, low risk, light modular construction which utilizes conventional materials and technology, and standard photovoltaic solar cells and laydown processes. Mechanisms, restraint/release devices, wiring harnesses, substrates, and support structures are designed to be simple, functional, lightweight, and modular. A brief overview of the Astro Edge solar array is discussed.
The Effects of Surface Roughness on the NEAR XRS Elemental Results: Monte-Carlo Modeling

NASA Technical Reports Server (NTRS)

Lin, Lucy F.; Nittler, Larry R.

2011-01-01

The objective of the NEAR-Shoemaker X-ray Gamma-Ray Spec1roscopy ("XGRS") investigation was to determine the elemental composition of the near-Earth asteroid 433 Eros. The X-ray Spectrometer (XRS) system measured the characteristic fluorescence of six major elements (Mg, Al, Si, S, Ca, Fe) in the 1-10 keV energy range excited by the interaction of solar X-rays with the upper 100 microns of the surface of 433 Eros. Various investigators, using both laboratory experiments and computer simulations have established that X-ray fluorescent line ratios can be influenced by small-scale surface roughness at high incidence or emission angles. The effect on the line ratio is specific to the geometry, excitation spectrum, and composition involved, In general, however, the effect is only substantial for ratios of lines with a significant energy difference between them: Fe/Si and Ca/Si are much more likely to be affected than AI/Si or Mg/Si. We apply a Monte-Carlo code to the specific geometry and spectrum of a major NEAR XRS solar flare observation, using an H chondrite composition as the substrate. The seventeen most abundant elements were included in the composition model, from oxygen to titanium.
Astro STARS Camp

NASA Image and Video Library

2011-06-28

Tom Nicolaides, an aerospace technologist in the Engineering & Test Directorate at Stennis Space Center, looks on as 2011 Astro STARS participants take turns gazing at the sun through a special telescope. The sun-gazing activity was part of the Astro STARS (Spaceflight, Technology, Astronomy & Robotics at Stennis) camp for 13-to-15-year-olds June 27 - July 1. The weeklong science and technology camp is held each year onsite at the rocket engine test facility.
Astro Algebra [CD-ROM].

ERIC Educational Resources Information Center

1997

Astro Algebra is one of six titles in the Mighty Math Series from Edmark, a comprehensive line of math software for students from kindergarten through ninth grade. Many of the activities in Astro Algebra contain a unique technology that uses the computer to help students make the connection between concrete and abstract mathematics. This software…
Astro Camp Goes to Florida

NASA Image and Video Library

2007-08-08

Katie Craig, daughter of former Stennis Space Center Deputy Director Mark Craig, launches a 'balloon rocket' with the help of Rebecca Compretta, Astro Camp coordinator at SSC. SSC took Astro Camp on the road to Florida this week to engage children and their parents during activities surrounding the Aug. 8 launch of Space Shuttle Endeavour on NASA's STS-118 mission to the International Space Station. Astro Camp is SSC's popular space camp program designed to inspire and educate students using science and math principles.
Astro Camp Goes to Florida

NASA Technical Reports Server (NTRS)

2007-01-01

Katie Craig, daughter of former Stennis Space Center Deputy Director Mark Craig, launches a 'balloon rocket' with the help of Rebecca Compretta, Astro Camp coordinator at SSC. SSC took Astro Camp on the road to Florida this week to engage children and their parents during activities surrounding the Aug. 8 launch of Space Shuttle Endeavour on NASA's STS-118 mission to the International Space Station. Astro Camp is SSC's popular space camp program designed to inspire and educate students using science and math principles.
Project ASTRO-Tucson: An Educational Outreach Program For All Seasons

NASA Astrophysics Data System (ADS)

Walker, C. E.; Pompea, S. M.; Wilson, R.

2002-12-01

Project ASTRO-Tucson represents a flexible program that is broad in content coverage and has utility for a diverse educational audience. As such, Project ASTRO forms the core of the National Optical Astronomy Observatory's successful regional outreach program. The program is aligned with the National Science Education Standards, appeals to different teaching and learning styles and can be adapted for space, staff, and money constraints at individual schools. ASTRO is broad in its astronomy content coverage and also addresses the scientific process, best practices and pedagogy, student misconceptions, and authentic assessment issues. In Tucson it has been used successfully with elementary, middle and high school students of different ethnic backgrounds, as well as with handicap-challenged and under-served students. ASTRO-Tucson is one of 13 sites nationally that have collectively reached over 100,000 students in the last 6 years. The program's core element is the partnering of professional and amateur astronomers with K-12 teachers and community educators who want to enrich their astronomy and science teaching. The partnerships are extended through a training workshop, hands-on activities, effective educational materials, follow-up workshops, continued staff support, and connections to community resources. In turn, the interest generated by Project ASTRO has fostered new programs such as Family ASTRO (just begun in Tucson), which invites families to evening or weekend family events doing fun astronomy activities together. We will describe some of the lessons learned from the Project ASTRO and Family ASTRO programs in Tucson and discuss efforts to jump-start and localize a Project ASTRO-type program in Chile at Cerro Tololo Inter-American Observatory.
MIT Participation in the Data Analysis of the XRS and XIS Instruments on the Astro-E2 Mission

NASA Technical Reports Server (NTRS)

Bautz, Mark

2005-01-01

Since the inception of this grant six weeks ago, we have completed the initial activation of the Suzaku X-ray Imaging Spectrometer (XIS) (on 13 August) and we have supported initial calibration observations. The instrument is performing very well in all respects. We have characterized the spectral resolution and effective area of each XIS sensor. We are especially excited about the scientific opportunities provided by the XIS'S back- illuminated sensor, which exhibits spectral resolution in the sub-keV band unmatched by any X-ray CCD currently in orbit. As specified in our proposal, we have established a web site (http://space.mit.edu/XIS) on which we maintain an up-to-date summary of instrument performance characteristics. Gain, spectral resolution and system noise, as well as residual background rates, are currently available on this site. Although the particle background level is low compared with Chandra and XMM, we are currently evaluating methods to reduce it still further. Techniques under study include use of 5x5 mode information and alternative grade selection methods. Although the primary responsibility for development of instrument response functions rests with our Japanese colleagues, we are incorporating our latest measurements of spectral resolution into some temporary response functions which we hope to make available to the Suzaku General Observer Facility and the Science Working Group(SWG). We are also preparing proposals for use of SWG observing time.
NASA Night at Houston Astros, pregame ceremonies

NASA Image and Video Library

2005-09-13

Images from the pregame ceremonies during NASA Night at the Houston Astros game, taken at Minute Maid Park, Houston. View of Center Director Jefferson Howell, Astros owner Drayton McLane, and STS-114 crewmembers Eileen Collins, James Kelly and Charles Camarda, with Collins holding an Astros jersey reading Discovery 114.
Astro tourism: Astro Izery project

NASA Astrophysics Data System (ADS)

Mrozek, Tomasz; Kołomański, Sylwester; Żakowicz, Grzegorz; Kornafel, Stanisław; Czarnecki, Tomasz L.; Suchan, Pavel; Kamiński, Zbigniew

2015-03-01

The Astro Izery project is carried by several institutions from Poland and Czech Republic. Its aim is to educate and inform tourists, who visit the Izery Mountains, about astronomy and light pollution. The project consists of two activities: permanent (sundials, planetary path etc.) and periodic (meetings, workshops). After five years the project is in good health and will gain more elements in next years.
Shuttle PRCS plume contamination analysis for Astro-2 mission

NASA Technical Reports Server (NTRS)

Wang, Francis C.; Greene, Cindy

1993-01-01

The Astro-2 mission scheduled for Jan. 1995 flight is co-manifested with the Spartan experiment. The Astro instrument array consists of several telescopes operating in the UV spectrum. To obtain the desired 300 observations with the telescope array in a shorter time than the Astro-1 mission, it will be necessary to use the primary reaction control system (PRCS) rather than just the Vernier reaction control system. The high mass flow rate of the PRCS engines cause considerable concern about contamination due to PRCS plume return flux. Performance of these instruments depends heavily on the environment they encounter. The ability of the optical system to detect a remote signal depends not only on the intensity of the incoming signal, but also on the ensuing transmission loss through the optical train of the instrument. Performance of these instruments is thus dependent on the properties of the optical surface and the medium through which it propagates. The on-orbit contamination environment will have a strong influence on the performance of these instruments. The finding of a two-month study of the molecular contamination environment of the Astro-2 instruments due to PRCS thruster plumes during the planned Astro-2 mission are summarized.
Soft x-ray spectrometer (SXS): the high-resolution cryogenic spectrometer onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Mitsuda, Kazuhisa; Kelley, Richard L.; Akamatsu, Hiroki; Bialas, Thomas; Boyce, Kevin R.; Brown, Gregory V.; Canavan, Edgar; Chiao, Meng; Costantini, Elisa; den Herder, Jan-Willem; de Vries, Cor; DiPirro, Michael J.; Eckart, Megan E.; Ezoe, Yuichiro; Fujimoto, Ryuichi; Haas, Daniel; Hoshino, Akio; Ishikawa, Kumi; Ishisaki, Yoshitaka; Iyomoto, Naoko; Kilbourne, Caroline A.; Kimball, Mark; Kitamoto, Shunji; Konami, Saori; Leutenegger, Maurice A.; McCammon, Dan; Miko, Joseph; Mitsuishi, Ikuyuki; Murakami, Hiroshi; Murakami, Masahide; Noda, Hirofumi; Ogawa, Mina; Ohashi, Takaya; Okamoto, Atsushi; Ota, Naomi; Paltani, Stéphane; Porter, F. Scott; Sato, Kosuke; Sato, Yoichi; Sawada, Makoto; Seta, Hiromi; Shinozaki, Keisuke; Shirron, Peter J.; Sneiderman, Gary A.; Sugita, Hiroyuki; Szymkowiak, Andrew; Takei, Yoh; Tamagawa, Toru; Tashiro, Makoto S.; Terada, Yukikatsu; Tsujimoto, Masahiro; Yamada, Shinya; Yamasaki, Noriko Y.

2014-07-01

We present the development status of the Soft X-ray Spectrometer (SXS) onboard the ASTRO-H mission. The SXS provides the capability of high energy-resolution X-ray spectroscopy of a FWHM energy resolution of < 7eV in the energy range of 0.3 - 10 keV. It utilizes an X-ray micorcalorimeter array operated at 50 mK. The SXS microcalorimeter subsystem is being developed in an EM-FM approach. The EM SXS cryostat was developed and fully tested and, although the design was generally confirmed, several anomalies and problems were found. Among them is the interference of the detector with the micro-vibrations from the mechanical coolers, which is the most difficult one to solve. We have pursued three different countermeasures and two of them seem to be effective. So far we have obtained energy resolutions satisfying the requirement with the FM cryostat.
AstroBus On-Board Software

NASA Astrophysics Data System (ADS)

Biscarros, D.; Cantenot, C.; Séronie-Vivien, J.; Schmidt, G.

AstroBus on-board software is a customisable software for ERC32 based avionics implementing standard ESA Packet Utilization Standard functions. Its architecture based on generic design templates and relying on a library providing standard PUS TC, TM and event services enhances its reusability on various programs. Finally, AstroBus on-board software development and validation environment is based on last generation tools providing an optimised customisation environment.
Thin fused silica shells for high-resolution and large collecting area x-ray telescopes (like Lynx/XRS)

NASA Astrophysics Data System (ADS)

Civitani, M. M.; Hołyszko, J.; Vecchi, G.; Basso, S.; Citterio, O.; Ghigo, M.; Pareschi, G.; Parodi, G.; Incorvaia, S.

2017-09-01

The implementation of an X-ray mission with high imaging capabilities, similar to those achieved with Chandra (< 1 arc second Half Energy Width, HEW), but with a much larger throughput (2.5 m2 effective area @1 keV), represents a compelling request by the scientific community. To this end the Lynx/XRS mission is being studied in USA, with the participation of international partners. In order to figure out the challenging technological task of the mirror fabrication, different approaches are considered, based on monolithic and segmented shells. Starting from the experience done on the glass prototypal shell realized in the past years, the direct polishing of thin (2 mm thick) fused silica monolithic shells is being investigated as a possible solution. A temporary stiffening structure is designed to support the shell during the figuring and polishing operations and to manage the handling up to its integration in the telescope structure. After the grinding and the polishing phases, in order to achieve the required surface accuracy, a final ion beam figuring correction is foreseen. In this paper, we present the technological process and the results achieved so far on a prototypal shell under development.
AstroPAL: A Mentoring Program for Grad Students

NASA Astrophysics Data System (ADS)

Cabrera, Nicole

2016-01-01

The Astronomy Peer Advising Leaders program (AstroPAL) provides guidance for incoming grad students from a team of student volunteers who have passed their 2nd year Qualifier Exam. The purpose is to pair first years with a mentor who can help them through some of the stresses or difficulties that come with being a new grad student. AstroPALs and mentees meet privately about once a month in a casual setting to talk about how they're adjusting to the new surroundings, how they're handling the workload, etc. New students can join AstroPAL at any time during their first two years, and can stop receiving guidance once they feel comfortable in the program. Mentees will be assigned an AstroPAL based on preference and availability, and an AstroPAL Liason will always be in place to facilitate mentor reassignments or other issues if necessary. After passing the 2nd year Qualifier Exam, mentees are eligible to serve as mentors to incoming students.

AstroCV: Astronomy computer vision library

NASA Astrophysics Data System (ADS)

González, Roberto E.; Muñoz, Roberto P.; Hernández, Cristian A.

2018-04-01

AstroCV processes and analyzes big astronomical datasets, and is intended to provide a community repository of high performance Python and C++ algorithms used for image processing and computer vision. The library offers methods for object recognition, segmentation and classification, with emphasis in the automatic detection and classification of galaxies.
AstroSat: From Inception to Realization and Launch

NASA Astrophysics Data System (ADS)

Agrawal, P. C.

2017-06-01

The origin of the idea of AstroSat multi wavelength satellite mission and how it evolved over the next 15 years from a concept to the successful development of instruments for giving concrete shape to this mission, is recounted in this article. AstroSat is the outcome of intense deliberations in the Indian astronomy community leading to a consensus for a multi wavelength Observatory having broad spectral coverage over five decades in energy covering near-UV, far-UV, soft X-ray and hard X-ray bands. The multi wavelength observation capability of AstroSat with a suite of 4 co-aligned instruments and an X-ray sky monitor on a single satellite platform, imparts a unique character to this mission. AstroSat owes its realization to the collaborative efforts of the various ISRO centres, several Indian institutions, and a few institutions abroad which developed the 5 instruments and various sub systems of the satellite. AstroSat was launched on September 28, 2015 from India in a near equatorial 650 km circular orbit. The instruments are by and large working as planned and in the past 14 months more than 200 X-ray and UV sources have been studied with it. The important characteristics of AstroSat satellite and scientific instruments will be highlighted.
Astro Camp

NASA Image and Video Library

2012-06-12

Each year, more than 400 Mississippi and out-of-state youths visit Stennis Space Center for weeklong Astro Camp activities. In 2012, campers investigated the science behind 21st century space travel, particularly related to the International Space Station and how astronauts live and work aboard the orbiting space laboratory.
Astro Chile | CTIO

Science.gov Websites

Program PIA Program GO-FAAR Program Other Opportunities Tourism Visits to Tololo Astro tourism in Chile Tourism in Chile Information for travelers Visit Tololo Media Relations News Press Release Publications
The ASTRO-H (Hitomi) X-Ray Astronomy Satellite

NASA Technical Reports Server (NTRS)

Takahashi, Tadayuki; Kokubun, Motohide; Mitsuda, Kazuhisa; Kelley, Richard; Ohashi, Takaya; Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie; Allen, Steve; Anabuki, Naohisa;

2016-01-01

The Hitomi (ASTRO-H) mission is the sixth Japanese X-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E greater than 2 keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft X-rays to gamma-rays. After a successful launch on 2016 February 17, the spacecraft lost its function on 2016 March 26, but the commissioning phase for about a month provided valuable information on the on-board instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month.

The ASTRO-H (Hitomi) x-ray astronomy satellite

NASA Astrophysics Data System (ADS)

Takahashi, Tadayuki; Kokubun, Motohide; Mitsuda, Kazuhisa; Kelley, Richard; Ohashi, Takaya; Aharonian, Felix; Akamatsu, Hiroki; Akimoto, Fumie; Allen, Steve; Anabuki, Naohisa; Angelini, Lorella; Arnaud, Keith; Asai, Makoto; Audard, Marc; Awaki, Hisamitsu; Axelsson, Magnus; Azzarello, Philipp; Baluta, Chris; Bamba, Aya; Bando, Nobutaka; Bautz, Marshall; Bialas, Thomas; Blandford, Roger; Boyce, Kevin; Brenneman, Laura; Brown, Greg; Bulbul, Esra; Cackett, Edward; Canavan, Edgar; Chernyakova, Maria; Chiao, Meng; Coppi, Paolo; Costantini, Elisa; de Plaa, Jelle; den Herder, Jan-Willem; DiPirro, Michael; Done, Chris; Dotani, Tadayasu; Doty, John; Ebisawa, Ken; Eckart, Megan; Enoto, Teruaki; Ezoe, Yuichiro; Fabian, Andrew; Ferrigno, Carlo; Foster, Adam; Fujimoto, Ryuichi; Fukazawa, Yasushi; Furuzawa, Akihiro; Galeazzi, Massimiliano; Gallo, Luigi; Gandhi, Poshak; Gilmore, Kirk; Giustini, Margherita; Goldwurm, Andrea; Gu, Liyi; Guainazzi, Matteo; Haas, Daniel; Haba, Yoshito; Hagino, Kouichi; Hamaguchi, Kenji; Harayama, Atsushi; Harrus, Ilana; Hatsukade, Isamu; Hayashi, Takayuki; Hayashi, Katsuhiro; Hayashida, Kiyoshi; Hiraga, Junko; Hirose, Kazuyuki; Hornschemeier, Ann; Hoshino, Akio; Hughes, John; Ichinohe, Yuto; Iizuka, Ryo; Inoue, Yoshiyuki; Inoue, Hajime; Ishibashi, Kazunori; Ishida, Manabu; Ishikawa, Kumi; Ishimura, Kosei; Ishisaki, Yoshitaka; Itoh, Masayuki; Iwata, Naoko; Iyomoto, Naoko; Jewell, Chris; Kaastra, Jelle; Kallman, Timothy; Kamae, Tuneyoshi; Kara, Erin; Kataoka, Jun; Katsuda, Satoru; Katsuta, Junichiro; Kawaharada, Madoka; Kawai, Nobuyuki; Kawano, Taro; Kawasaki, Shigeo; Khangulyan, Dmitry; Kilbourne, Caroline; Kimball, Mark; King, Ashley; Kitaguchi, Takao; Kitamoto, Shunji; Kitayama, Tetsu; Kohmura, Takayoshi; Kosaka, Tatsuro; Koujelev, Alex; Koyama, Katsuji; Koyama, Shu; Kretschmar, Peter; Krimm, Hans; Kubota, Aya; Kunieda, Hideyo; Laurent, Philippe; Lebrun, François; Lee, Shiu-Huang; Leutenegger, Maurice; Limousin, Olivier; Loewenstein, Michael; Long, Knox; Lumb, David; Madejski, Grzegorz; Maeda, Yoshitomo; Maier, Daniel; Makishima, Kazuo; Markevitch, Maxim; Masters, Candace; Matsumoto, Hironori; Matsushita, Kyoko; McCammon, Dan; McGuinness, Daniel; McNamara, Brian; Mehdipour, Missagh; Miko, Joseph; Miller, Jon; Miller, Eric; Mineshige, Shin; Minesugi, Kenji; Mitsuishi, Ikuyuki; Miyazawa, Takuya; Mizuno, Tsunefumi; Mori, Koji; Mori, Hideyuki; Moroso, Franco; Moseley, Harvey; Muench, Theodore; Mukai, Koji; Murakami, Hiroshi; Murakami, Toshio; Mushotzky, Richard; Nagano, Housei; Nagino, Ryo; Nakagawa, Takao; Nakajima, Hiroshi; Nakamori, Takeshi; Nakano, Toshio; Nakashima, Shinya; Nakazawa, Kazuhiro; Namba, Yoshiharu; Natsukari, Chikara; Nishioka, Yusuke; Nobukawa, Masayoshi; Nobukawa, Kumiko; Noda, Hirofumi; Nomachi, Masaharu; O'Dell, Steve; Odaka, Hirokazu; Ogawa, Hiroyuki; Ogawa, Mina; Ogi, Keiji; Ohno, Masanori; Ohta, Masayuki; Okajima, Takashi; Okamoto, Atsushi; Okazaki, Tsuyoshi; Ota, Naomi; Ozaki, Masanobu; Paerels, Frederik; Paltani, Stéphane; Parmar, Arvind; Petre, Robert; Pinto, Ciro; Pohl, Martin; Pontius, James; Porter, F. Scott; Pottschmidt, Katja; Ramsey, Brian; Reynolds, Christopher; Russell, Helen; Safi-Harb, Samar; Saito, Shinya; Sakai, Shin-ichiro; Sakai, Kazuhiro; Sameshima, Hiroaki; Sasaki, Toru; Sato, Goro; Sato, Yoichi; Sato, Kosuke; Sato, Rie; Sawada, Makoto; Schartel, Norbert; Serlemitsos, Peter; Seta, Hiromi; Shibano, Yasuko; Shida, Maki; Shidatsu, Megumi; Shimada, Takanobu; Shinozaki, Keisuke; Shirron, Peter; Simionescu, Aurora; Simmons, Cynthia; Smith, Randall; Sneiderman, Gary; Soong, Yang; Stawarz, Łukasz; Sugawara, Yasuharu; Sugita, Hiroyuki; Sugita, Satoshi; Szymkowiak, Andrew; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takeda, Shin'ichiro; Takei, Yoh; Tamagawa, Toru; Tamura, Takayuki; Tamura, Keisuke; Tanaka, Takaaki; Tanaka, Yasuo; Tanaka, Yasuyuki; Tashiro, Makoto; Tawara, Yuzuru; Terada, Yukikatsu; Terashima, Yuichi; Tombesi, Francesco; Tomida, Hiroshi; Tsuboi, Yohko; Tsujimoto, Masahiro; Tsunemi, Hiroshi; Tsuru, Takeshi; Uchida, Hiroyuki; Uchiyama, Yasunobu; Uchiyama, Hideki; Ueda, Yoshihiro; Ueda, Shutaro; Ueno, Shiro; Uno, Shin'ichiro; Urry, Meg; Ursino, Eugenio; de Vries, Cor; Wada, Atsushi; Watanabe, Shin; Watanabe, Tomomi; Werner, Norbert; Wik, Daniel; Wilkins, Dan; Williams, Brian; Yamada, Takahiro; Yamada, Shinya; Yamaguchi, Hiroya; Yamaoka, Kazutaka; Yamasaki, Noriko; Yamauchi, Makoto; Yamauchi, Shigeo; Yaqoob, Tahir; Yatsu, Yoichi; Yonetoku, Daisuke; Yoshida, Atsumasa; Yuasa, Takayuki; Zhuravleva, Irina; Zoghbi, Abderahmen

2016-07-01

The Hitomi (ASTRO-H) mission is the sixth Japanese X-ray astronomy satellite developed by a large international collaboration, including Japan, USA, Canada, and Europe. The mission aimed to provide the highest energy resolution ever achieved at E > 2 keV, using a microcalorimeter instrument, and to cover a wide energy range spanning four decades in energy from soft X-rays to gamma-rays. After a successful launch on 2016 February 17, the spacecraft lost its function on 2016 March 26, but the commissioning phase for about a month provided valuable information on the on-board instruments and the spacecraft system, including astrophysical results obtained from first light observations. The paper describes the Hitomi (ASTRO-H) mission, its capabilities, the initial operation, and the instruments/spacecraft performances confirmed during the commissioning operations for about a month.
Astro Camp Counselors

NASA Technical Reports Server (NTRS)

2007-01-01

Barbara Marino (left), Stennis Space Center education technology specialist, shows Astro Camp Counselor Beverly Fitzsimmons a LEGO model during a teambuilding exercise May 29 at SSC's North Gate computer lab as a part of the counselors' `new hire' orientation.
Astro Camp Counselors

NASA Image and Video Library

2007-06-08

Barbara Marino (left), Stennis Space Center education technology specialist, shows Astro Camp Counselor Beverly Fitzsimmons a LEGO model during a teambuilding exercise May 29 at SSC's North Gate computer lab as a part of the counselors' `new hire' orientation.
Historical Review of Astro-Geodetic Observations in Serbia

NASA Astrophysics Data System (ADS)

Ogrizovic, V.; Delcev, S.; Vasilic, V.; Gucevic, J.

2008-10-01

Astro-geodetic determinations of vertical deflections in Serbia began during the first years of 20th century. The first field works were led by S. Bo\\vsković. After the 2nd World War, Military Geographic Institute, Department of Geodesy from the Faculty of Civil Engineering, and Federal Geodetic Directorate continued the determinations, needed for reductions of terrestrial geodetic measurements and the astro-geodetic geoid determination. Last years improvements of the astro-geodetic methods are carried out in the area of implementing modern measurement equipment and technologies.
Onboard photo:Astro-1 in Cargo Bay

NASA Technical Reports Server (NTRS)

1990-01-01

Onboard the Space Shuttle Orbiter Columbia (STS-35), the various components of the Astro-1 payload are seen backdropped against dark space. Parts of the Hopkins Ultraviolet Telescope (HUT), Ultraviolet Imaging Telescope (UIT), and the Wisconsin Ultraviolet Photo-Polarimetry Experiment (WUPPE) are visible on the Spacelab pallet. The Broad-Band X-Ray Telescope (BBXRT) is behind the pallet and is not visible in this scene. The smaller cylinder in the foreground is the igloo. The igloo was a pressurized container housing the Command Data Management System, that interfaced with the in-cabin controllers to control the Instrument Pointing System (IPS) and the telescopes. The Astro Observatory was designed to explore the universe by observing and measuring the ultraviolet radiation from celestial objects. Astronomical targets of observation selected for Astro missions included planets, stars, star clusters, galaxies, clusters of galaxies, quasars, remnants of exploded stars (supernovae), clouds of gas and dust (nebulae), and the interstellar medium. Managed by the Marshall Space Flight Center, the Astro-1 was launched aboard the Space Shuttle Orbiter Columbia (STS-35) on December 2, 1990.
IPS guidestar selection for stellar mode (ASTRO)

NASA Technical Reports Server (NTRS)

Mullins, Larry; Wooten, Lewis

1988-01-01

This report describes how guide stars are selected for the Optical Sensor Package (OSP) for the Instrument Pointing System (IPS) when it is operating in the stellar mode on the ASTRO missions. It also describes how the objective loads are written and how the various roll angles are related; i.e., the celestial roll or position angle, the objective load roll angles, and the IPS gimbal angles. There is a brief description of how the IPS operates and its various modes of operation; i.e., IDOP, IDIN, and OSPCAL.
Testing of Twin Linear Aerospike XRS-2200 Engine

NASA Technical Reports Server (NTRS)

2001-01-01

The test of twin Linear Aerospike XRS-2200 engines, originally built for the X-33 program, was performed on August 6, 2001 at NASA's Sternis Space Center, Mississippi. The engines were fired for the planned 90 seconds and reached a planned maximum power of 85 percent. NASA's Second Generation Reusable Launch Vehicle Program , also known as the Space Launch Initiative (SLI), is making advances in propulsion technology with this third and final successful engine hot fire, designed to test electro-mechanical actuators. Information learned from this hot fire test series about new electro-mechanical actuator technology, which controls the flow of propellants in rocket engines, could provide key advancements for the propulsion systems for future spacecraft. The Second Generation Reusable Launch Vehicle Program, led by NASA's Marshall Space Flight Center in Huntsville, Alabama, is a technology development program designed to increase safety and reliability while reducing costs for space travel. The X-33 program was cancelled in March 2001.
Augmenting the Funding Sources for Space Science and the ASTRO-1 Space Telescope

NASA Astrophysics Data System (ADS)

Morse, Jon

2015-08-01

The BoldlyGo Institute was formed in 2013 to augment the planned space science portfolio through philanthropically funded robotic space missions, similar to how some U.S. medical institutes and ground-based telescopes are funded. I introduce BoldlyGo's two current projects: the SCIM mission to Mars and the ASTRO-1 space telescope. In particular, ASTRO-1 is a 1.8-meter off-axis (unobscured) ultraviolet-visible space observatory to be located in a Lagrange point or heliocentric orbit with a wide-field panchromatic camera, medium- and high-resolution spectrograph, and high-contrast imaging coronagraph and/or an accompanying starshade/occulter. It is intended for the post-Hubble Space Telescope era in the 2020s, enabling unique measurements of a broad range of celestial targets, while providing vital complementary capabilities to other ground- and space-based facilities such as the JWST, ALMA, WFIRST-AFTA, LSST, TESS, Euclid, and PLATO. The ASTRO-1 architecture simultaneously wields great scientific power while being technically viable and affordable. A wide variety of scientific programs can be accomplished, addressing topics across space astronomy, astrophysics, fundamental physics, and solar system science, as well as being technologically informative to future large-aperture programs. ASTRO-1 is intended to be a new-generation research facility serving a broad national and international community, as well as a vessel for impactful public engagement. Traditional institutional partnerships and consortia, such as are common with private ground-based observatories, may play a role in the support and governance of ASTRO-1; we are currently engaging interested international organizations. In addition to our planned open guest observer program and accessible data archive, we intend to provide a mechanism whereby individual scientists can buy in to a fraction of the gauranteed observing time. Our next step in ASTRO-1 development is to form the ASTRO-1 Requirements Team
Astro-1 Image Taken by the Ultraviolet Imaging Telescope

NASA Technical Reports Server (NTRS)

1990-01-01

This is a presentation of two comparison images of the Spiral Galaxy M81 in the constellation URA Major. The galaxy is about 12-million light years from Earth. The left image is the Spiral Galaxy M81 as photographed by the Ultraviolet Imaging Telescope (UIT) during the Astro-1 Mission (STS-35) on December 9, 1990. This UIT photograph, made with ultraviolet light, reveals regions where new stars are forming at a rapid rate. The right image is a photograph of the same galaxy in red light made with a 36-inch (0.9-meter) telescope at the Kitt Peak National Observatory near Tucson, Arizona. The Astro Observatory was designed to explore the universe by observing and measuring ultraviolet radiation from celestial objects. Three instruments made up the Astro Observatory: The Hopkins Ultraviolet Telescope (HUT), the Ultraviolet Imaging Telescope (UIT), and the Wisconsin Ultraviolet Photo-Polarimetry Experiment (WUPPE). The Marshall Space Flight Center had management responsibilities for the Astro-1 mission. The Astro-1 Observatory was launched aboard the Space Shuttle Orbiter Columbia (STS-35) on December 2, 1990.
The Astro-Blaster.

ERIC Educational Resources Information Center

Mancuso, Richard V.; Long, Kevin R.

1995-01-01

Presents the Astro-Blaster as a method of the laws of conservation of momentum and energy during the creation of a supernova. Several elastic balls are aligned for a drop, followed by multiple collisions which result in the top ball reaching tremendous heights relative to the drop height. (JRH)
AstroCappella: Songs of the Universe

NASA Astrophysics Data System (ADS)

Boyd, P. T.; Smale, A. P.; Smale, K. M.

2008-11-01

The AstroCappella Project is a classroom-ready collection of upbeat pop songs, lesson plans, and background information, all rich in science content. It was developed as a collaboration between working research astronomers, educators, and a contemporary vocal band, The Chromatics. A multimedia music CD, ``AstroCappella 2.0,'' has been produced containing 13 astronomically correct songs with original lyrics and music. Song topics range from the Sun, Moon, planets and small bodies of the Solar System, through the Doppler shift, the nearest stars, and extra-solar planets, to radio and X-ray astronomy. The CD also contains extensive CD-ROM materials including science background information, curriculum notes, lesson plans and activities for each song, images, movies, and slide shows. The songs and accompanying information have been extensively field-tested, and align to the K--12 National Science Education Standards. The AstroCappella materials are in widespread use in classrooms and homes across the U.S., and are supplemented with frequent live performances and teacher workshops.
ASTRO's core physics curriculum for radiation oncology residents.

PubMed

Klein, Eric E; Balter, James M; Chaney, Edward L; Gerbi, Bruce J; Hughes, Lesley

2004-11-01

In 2002, the Radiation Physics Committee of the American Society of Therapeutic Radiology and Oncology (ASTRO) appointed an Ad-hoc Committee on Physics Teaching to Medical Residents. The main initiative of the committee was to develop a core curriculum for physics education. Prior publications that have analyzed physics teaching have pointed to wide discrepancies among teaching programs. The committee was composed of physicists or physicians from various residency program based institutions. Simultaneously, members had associations with the American Association of Physicists in Medicine (AAPM), ASTRO, Association of Residents in Radiation Oncology (ARRO), American Board of Radiology (ABR), and the American College of Radiology (ACR). The latter two organizations' representatives were on the physics examination committees, as one of the main agendas was to provide a feedback loop between the examining organizations and ASTRO. The document resulted in a recommended 54-h course. Some of the subjects were based on American College of Graduate Medical Education (ACGME) requirements (particles, hyperthermia), whereas the majority of the subjects along with the appropriated hours per subject were devised and agreed upon by the committee. For each subject there are learning objectives and for each hour there is a detailed outline of material to be covered. Some of the required subjects/h are being taught in most institutions (i.e., Radiation Measurement and Calibration for 4 h), whereas some may be new subjects (4 h of Imaging for Radiation Oncology). The curriculum was completed and approved by the ASTRO Board in late 2003 and is slated for dissemination to the community in 2004. It is our hope that teaching physicists will adopt the recommended curriculum for their classes, and simultaneously that the ABR for its written physics examination and the ACR for its training examination will use the recommended curriculum as the basis for subject matter and depth of
AstroML: Python-powered Machine Learning for Astronomy

NASA Astrophysics Data System (ADS)

Vander Plas, Jake; Connolly, A. J.; Ivezic, Z.

2014-01-01

As astronomical data sets grow in size and complexity, automated machine learning and data mining methods are becoming an increasingly fundamental component of research in the field. The astroML project (http://astroML.org) provides a common repository for practical examples of the data mining and machine learning tools used and developed by astronomical researchers, written in Python. The astroML module contains a host of general-purpose data analysis and machine learning routines, loaders for openly-available astronomical datasets, and fast implementations of specific computational methods often used in astronomy and astrophysics. The associated website features hundreds of examples of these routines being used for analysis of real astronomical datasets, while the associated textbook provides a curriculum resource for graduate-level courses focusing on practical statistics, machine learning, and data mining approaches within Astronomical research. This poster will highlight several of the more powerful and unique examples of analysis performed with astroML, all of which can be reproduced in their entirety on any computer with the proper packages installed.
AstroCappella: A Musical Exploration of the Universe. Activities and Information To Accompany the AstroCappella CD. Grades 7-12.

ERIC Educational Resources Information Center

Boyd, Padi; Granger, Kara C.; Smale, Alan

AstroCappella combines the love of music with the love of astronomy. The booklet contains hands-on activities that can be done in the classroom coupled with rocking, high-energy, professionally recorded and produced songs written and performed by an established vocal band. The lesson plans help students learn how convection works, how radio…
AstroMadrid: Astrophysics and technological developments in Comunidad de Madrid

NASA Astrophysics Data System (ADS)

Mas-Hesse, J. M.

2011-11-01

AstroMadrid is a network constituted by different research groups in the Comunidad de Madrid area, with the objective of coordinating the activities related to the development of astronomical instrumentation in the various centres. AstroMadrid is a multidisciplinar team which benefits from the synergies provided by the different participating groups, optimizing our capabilities to develop instrumentation, and minimizing the problems related to the geographical dispersion within our region. AstroMadrid is also participated by several aerospace industries, which complement the capabilities and facilities available in the research centres. In addition to optimizing the development of instrumentation, AstroMadrid plays an essential role in the formation of new engineers and scientists, by actively contributing to some Master degree courses organized by different Universities in Madrid.

Wavelength calibration with PMAS at 3.5 m Calar Alto Telescope using a tunable astro-comb

NASA Astrophysics Data System (ADS)

Chavez Boggio, J. M.; Fremberg, T.; Bodenmüller, D.; Sandin, C.; Zajnulina, M.; Kelz, A.; Giannone, D.; Rutowska, M.; Moralejo, B.; Roth, M. M.; Wysmolek, M.; Sayinc, H.

2018-05-01

On-sky tests conducted with an astro-comb using the Potsdam Multi-Aperture Spectrograph (PMAS) at the 3.5 m Calar Alto Telescope are reported. The proposed astro-comb approach is based on cascaded four-wave mixing between two lasers propagating through dispersion optimized nonlinear fibers. This approach allows for a line spacing that can be continuously tuned over a broad range (from tens of GHz to beyond 1 THz) making it suitable for calibration of low- medium- and high-resolution spectrographs. The astro-comb provides 300 calibration lines and his line-spacing is tracked with a wavemeter having 0.3 pm absolute accuracy. First, we assess the accuracy of Neon calibration by measuring the astro-comb lines with (Neon calibrated) PMAS. The results are compared with expected line positions from wavemeter measurement showing an offset of ∼5-20 pm (4%-16% of one resolution element). This might be the footprint of the accuracy limits from actual Neon calibration. Then, the astro-comb performance as a calibrator is assessed through measurements of the Ca triplet from stellar objects HD3765 and HD219538 as well as with the sky line spectrum, showing the advantage of the proposed astro-comb for wavelength calibration at any resolution.
Songs of the Universe - The AstroCappella Project

NASA Astrophysics Data System (ADS)

Boyd, P. T.; Smale, K. M.; Smale, A. P.

2004-12-01

The AstroCappella Project is a classroom-ready collection of upbeat pop songs, lesson plans, and background information, all rich in science content. It was developed as a collaboration between working research astronomers, educators, and a contemporary vocal band. A multimedia music CD ("AstroCappella 2.0") has been produced containing 13 astronomically correct songs with original lyrics and music. Song topics range from the Sun, Moon, planets and small bodies of the Solar System, through the Doppler shift, the nearest stars, and extra-solar planets, to radio astronomy, X-ray astronomy, and the Hubble Space Telescope and Swift astronomy satellites. The CD also contains extensive CD-ROM materials including science background information, curriculum notes, lesson plans and activities for each song, images, movies, and slide shows. The songs and accompanying information have been extensively field-tested, and align to the K-12 National Science Education Standards. The AstroCappella materials are in widespread use in classrooms and homes across the US, and are supplemented with frequent live performances and teacher workshops. We describe here the history, content, and educational strategy behind the AstroCappella Project, and the plans for its future development.
AstroCappella: Songs of the Universe

NASA Astrophysics Data System (ADS)

Boyd, Patricia T.; Smale, A. P.; Smale, K. M.

2008-05-01

The AstroCappella Project is a classroom-ready collection of upbeat pop songs, lesson plans, and background information, all rich in science content. It was developed as a collaboration between working research astronomers, educators, and an established contemporary vocal band, The Chromatics. A multimedia music CD, "AstroCappella 2.0", has been produced containing 13 astronomically correct songs with original lyrics and music. Song topics range from the Sun, Moon, planets and small bodies of the Solar System, through the Doppler shift, the nearest stars, and extra-solar planets, to radio and X-ray astronomy. The CD also contains extensive CD-ROM materials including science background information, curriculum notes, lesson plans and activities for each song, images, movies, and slide shows. The songs and accompanying information have been extensively field-tested, and align to the K-12 National Science Education Standards. The AstroCappella materials are in widespread use in classrooms and homes across the US, and are supplemented with frequent live performances and teacher workshops. Full information can be found at http://www.astrocappella.com. Since the release of AstroCappella 2.0, additional songs have been written for missions as diverse as Messenger ("Messenger to Mercury") and AIM ("Noctilucent Cloud"; with music video available on YouTube). Now, to commemorate IYA, and in collaboration with the Johannes Kepler Project, the Chromatics are continuing their mission to spread science through a cappella and a cappella through science by creating a new original song celebrating the discoveries of the telescope, from Galileo's first glimpse of mountains and craters on the moon to the detection of planets around nearby stars and the expansion of the Universe."
Elemental Composition of 433 Eros: New Calibration of the NEAR-Shoemaker XRS Data

NASA Technical Reports Server (NTRS)

Lim, Lucy F.; Nittler, Larry R.

2009-01-01

We present a new calibration of the elemental-abundance data for Asteroid 433 Fros taken by the X-ray spectrometer (XRS) aboard the NEAR-Shoemaker spacecraft. (NEAR is an acronym for "Near-Earth Asteroid Rendezvous,") Quintification of the asteroid surface elemental abundance ratios depends critically on accurate knowledge of the incident solar X-ray spectrum, which was monitored simultaneously with asteroid observations. Previously published results suffered from incompletely characterized systematic uncertainties due to an imperfect ground calibrations of the NEAR gas solar monitor. The solar monitor response function and associated uncertainties have now been characterized by cross-calibration of a large sample of NEAR solar monitor flight data against. contemporary broadband solar X-ray data from the Earth-orbiting GOES-8 (Geostationary Operational Environmental Satellite). The results have been used to analyze XRS spectra acquired from Eros during eight major solar flares (including three that have not previously been reported). The end product of this analysis is a revised set of Eros surface elemental abundance ratios with new error estimates that more accurately reflect the remaining uncertainties in the solar flare spectra: Mg/Si=.753 +0.078/-0.055, Al/Si=0.069 +/-0.055, S/Si=0.005+/-0.008, Ca/Si=0.060+0.023/-0.024, and Fe/Si= 1.578+0.338/-0.320. These revised abundance ratios are consitent within cited uncertainties with the results of Nittler et al. [Nittler, L.R., and 14 colleagues, 2001. Meteorit Planet. Sci 36, 1673-1695] and thus support the prior conclusions that 433 Eros has major-element composition simular to ordinary chondrites with the exception of a stong depletoin in sulfur, most likely caused by space weathering.
AstroBetter: A Blog and Wiki for Professional Astronomers

NASA Technical Reports Server (NTRS)

Rigby, Jane

2011-01-01

AstroBetter.com is a multi-contributor blog and wiki website designed for information sharing among professional astronomers. The goal of the site is to increase the productivity of astronomers by creating a centralized location for tips and tools of our multifaceted trade. Our content includes topics related to data reduction and analysis, general computing, writing papers and proposals, giving talks, teaching, career planning, productivity, organization, and diversity and equity in science and education. While we have several contributors, the site is intended to be community driven and we encourage everyone to publish to the wiki, submit guest posts, suggest post ideas, and to comment on blog entries. One of our primary goals is to consolidate and reduce the transient nature of the astronomy community's collective knowledge base by having an active wiki. Currently, the most common way to share astro-centric tools and tips that are not appropriate for a published paper, is to put them on an individual's website. However, the average astronomer's website will have at least four different addresses over the course of their career and only the site owner can edit the content. As a result, information on personal websites goes stale very quickly and deal links to such sites abound. It is our hope that community maintained wikis, such as the one hosted on AstroBetter, will gradually replace the personal website. In this poster we introduce the contributors to AstroBetter, show statistics about our current readership, give excerpts of some of our most popular posts and wiki entries, and show how anyone can add or edit content on the wiki. The goal of this poster is to spread the work about AstroBetter and increase our community of readers and wiki editors, because together, we can AstroBetter.
Onboard Photo:Astro-1 Ultraviolet Telescope in Cargo Bay

NASA Technical Reports Server (NTRS)

1990-01-01

Onboard the Space Shuttle Orbiter Columbia (STS-35), the various components of the Astro-1 payload are seen backdropped against a blue and white Earth. Parts of the Hopkins Ultraviolet Telescope (HUT), the Ultraviolet Imaging Telescope (UIT), and the Wisconsin Ultraviolet Photo-Polarimetry Experiment (WUPPE) are visible on the Spacelab pallet. The Broad-Band X-Ray Telescope (BBXRT) is behind the pallet and is not visible in this scene. The smaller cylinder in the foreground is the igloo. The igloo was a pressurized container housing the Command Data Management System, that interfaced with the in-cabin controllers to control the Instrument Pointing System (IPS) and the telescopes. The Astro Observatory was designed to explore the universe by observing and measuring the ultraviolet radiation from celestial objects. Astronomical targets of observation selected for Astro missions included planets, stars, star clusters, galaxies, clusters of galaxies, quasars, remnants of exploded stars (supernovae), clouds of gas and dust (nebulae), and the interstellar medium. Managed by the Marshall Space Flight Center, the Astro-1 was launched aboard the Space Shuttle Orbiter Columbia (STS-35) on December 2, 1990.
Introducing AstroGen: the Astronomy Genealogy Project

NASA Astrophysics Data System (ADS)

Tenn, Joseph S.

2016-12-01

The Astronomy Genealogy Project (AstroGen), a project of the Historical Astronomy Division of the American Astronomical Society (AAS), will soon appear on the AAS website. Ultimately, it will list the world's astronomers with their highest degrees, theses for those who wrote them, academic advisors (supervisors), universities, and links to the astronomers or their obituaries, their theses when online, and more. At present the AstroGen team is working on those who earned doctorates with astronomy-related theses. We show what can be learned already, with just ten countries essentially completed.
AstroFest: A Case Study of an Astronomy Outreach Program at Penn State University

NASA Astrophysics Data System (ADS)

Palma, C.; Charlton, J. C.

2003-12-01

The Pennsylvania State University Department of Astronomy & Astrophysics has developed a multi-faceted approach to outreach in astronomy. Our programs include In-Service Workshops in Astronomy for middle-school and high-school science teachers, planetarium shows for local elementary school classes, and a series of sponsored, popular level talks, for example. One of our most popular outreach events is called ``AstroFest"; this is a four night festival of astronomy that we hold concurrently with the Central Pennsylvania Festival of the Arts (``ArtsFest"). The AstroFest program was devised by undergraduate students during the summer of 1999, and we continue to hold it annually. Each night of the event, we offer talks at a popular level on subjects such as black holes, life on Mars, and the world's largest telescopes. Throughout the night we also offer planetarium shows, a chance to use our rooftop telescopes, a question & answer table with prizes, kids' activities that include launching bubble rockets, and a number of other demonstrations and tours. In this poster, I present the full complement of astronomy outreach programs offered by Penn State, and I focus in particular on AstroFest as a case study that highlights the challenges we face and the positive outcomes we have realized. Funding for our outreach program has come from several sources, including NASA E/PO supplement grants, the STScI IDEAS program, The Pennsylvania Space Grant Consortium, and the Pennsylvania State University Eberly College of Science.
AstroBlend: Visualization package for use with Blender

NASA Astrophysics Data System (ADS)

Naiman, J. P.

2015-12-01

AstroBlend is a visualization package for use in the three dimensional animation and modeling software, Blender. It reads data in via a text file or can use pre-fab isosurface files stored as OBJ or Wavefront files. AstroBlend supports a variety of codes such as FLASH (ascl:1010.082), Enzo (ascl:1010.072), and Athena (ascl:1010.014), and combines artistic 3D models with computational astrophysics datasets to create models and animations.
Simulating Astro-H Observations of Sloshing Gas Motions in the Cores of Galaxy Clusters

NASA Astrophysics Data System (ADS)

ZuHone, J. A.; Miller, E. D.; Simionescu, A.; Bautz, M. W.

2016-04-01

Astro-H will be the first X-ray observatory to employ a high-resolution microcalorimeter, capable of measuring the shift and width of individual spectral lines to the precision necessary for estimating the velocity of the diffuse plasma in galaxy clusters. This new capability is expected to bring significant progress in understanding the dynamics, and therefore the physics, of the intracluster medium. However, because this plasma is optically thin, projection effects will be an important complicating factor in interpreting future Astro-H measurements. To study these effects in detail, we performed an analysis of the velocity field from simulations of a galaxy cluster experiencing gas sloshing and generated synthetic X-ray spectra, convolved with model Astro-H Soft X-ray Spectrometer (SXS) responses. We find that the sloshing motions produce velocity signatures that will be observable by Astro-H in nearby clusters: the shifting of the line centroid produced by the fast-moving cold gas underneath the front surface, and line broadening produced by the smooth variation of this motion along the line of sight. The line shapes arising from inviscid or strongly viscous simulations are very similar, indicating that placing constraints on the gas viscosity from these measurements will be difficult. Our spectroscopic analysis demonstrates that, for adequate exposures, Astro-H will be able to recover the first two moments of the velocity distribution of these motions accurately, and in some cases multiple velocity components may be discerned. The simulations also confirm the importance of accurate treatment of point-spread function scattering in the interpretation of Astro-H/SXS spectra of cluster plasmas.
Astro STARS Camp

NASA Image and Video Library

2012-06-15

Summer is a time of educational activity at Stennis Space Center. In June 2012, 25 young people age 13-15 attended the annual Astro STARS (Spaceflight, Technology, Astronomy and Robotics at Stennis) camp at the rocket engine test facility. During the five-day camp, participants engaged in hands-on experiences in a variety of areas, including engineering and robotics. On the final day, campers launched model rockets they had assembled.
Astro Stars Camp features underwater robotics

NASA Image and Video Library

2010-06-29

Ian Tonglet, 13, (left) and Seth Malley, 13, both of Picayune, Miss., and both participants in the 2010 Astro Stars session at Stennis Space Center, work with an underwater robot during a camp activity June 29. NASA joined with the U.S. Navy for the underwater robotics exercise involving Sea Perch robots, which are simple, remotely operated underwater vehicles made from PVC pipe and other inexpensive, easily available materials. During the Stennis exercise, students used robots constructed earlier in the day to maneuver underwater and collect plastic rings, as seen to the left of Tonglet. Astro STARS (Spaceflight, Technology, Astronomy & Robotics @ Stennis) is a science and technology camp for 13-15 year olds.
AstroGrid: Taverna in the Virtual Observatory .

NASA Astrophysics Data System (ADS)

Benson, K. M.; Walton, N. A.

This paper reports on the implementation of the Taverna workbench by AstroGrid, a tool for designing and executing workflows of tasks in the Virtual Observatory. The workflow approach helps astronomers perform complex task sequences with little technical effort. Visual approach to workflow construction streamlines highly complex analysis over public and private data and uses computational resources as minimal as a desktop computer. Some integration issues and future work are discussed in this article.
Astronaut John Grunsfeld uses camera to record ASTRO-2 payload

NASA Image and Video Library

1995-03-17

STS067-377-008 (2-18 March 1995) --- Astronaut John M. Grunsfeld, mission specialist, uses a handheld Hasselblad camera to record the Astro-2 payload. Orbiting Earth at 190 nautical miles, Grunsfeld joined four other NASA astronauts and two scientists for almost 17 days conducting research in support of the Astro-2 mission.
Keesler Astro Camp

NASA Image and Video Library

2011-06-29

Young people prepare model rockets during an Astro Camp activity at Keesler Air Force Base in Biloxi. Stennis hosted the camp June 28 - July 1 in support of the White House Military Families Initiative. The camp also marked the beginning of a partnership between Stennis and Keesler to provide NASA education experiences to military children and to train children and youth care-providers. It is hoped that this activity can be expanded to other military bases next summer.
Astrobites: The Astro-ph Reader's Digest For Undergraduates

NASA Astrophysics Data System (ADS)

Kohler, Susanna; Weiss, L. M.; Faesi, C. M.; Astrobites Team

2012-05-01

Astrobites (http://astrobites.com) is a daily blog aimed primarily at undergraduates interested in astrophysical research and written by a team of graduate students located at diverse institutes around the country and Europe. Every day we present a journal article recently posted to astro-ph in a brief format that is accessible to anyone with a general background in the physical sciences. In addition to summarizing new work, Astrobites provides valuable context for readers not yet familiar with the astrophysical literature. Special posts offer career guidance for undergraduates (e.g. applying for an NSF graduate fellowship) and describe personal experiences (e.g. attending an astronomy summer school). We will discuss the Astrobites format and recent readership statistics.
Selections from 2017: Image Processing with AstroImageJ

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-12-01

Editors note:In these last two weeks of 2017, well be looking at a few selections that we havent yet discussed on AAS Nova from among the most-downloaded paperspublished in AAS journals this year. The usual posting schedule will resume in January.AstroImageJ: Image Processing and Photometric Extraction for Ultra-Precise Astronomical Light CurvesPublished January2017The AIJ image display. A wide range of astronomy specific image display options and image analysis tools are available from the menus, quick access icons, and interactive histogram. [Collins et al. 2017]Main takeaway:AstroImageJ is a new integrated software package presented in a publication led byKaren Collins(Vanderbilt University,Fisk University, andUniversity of Louisville). Itenables new users even at the level of undergraduate student, high school student, or amateur astronomer to quickly start processing, modeling, and plotting astronomical image data.Why its interesting:Science doesnt just happen the momenta telescope captures a picture of a distantobject. Instead, astronomical images must firstbe carefully processed to clean up thedata, and this data must then be systematically analyzed to learn about the objects within it. AstroImageJ as a GUI-driven, easily installed, public-domain tool is a uniquelyaccessible tool for thisprocessing and analysis, allowing even non-specialist users to explore and visualizeastronomical data.Some features ofAstroImageJ:(as reported by Astrobites)Image calibration:generate master flat, dark, and bias framesImage arithmetic:combineimages viasubtraction, addition, division, multiplication, etc.Stack editing:easily perform operations on a series of imagesImage stabilization and image alignment featuresPrecise coordinate converters:calculate Heliocentric and Barycentric Julian DatesWCS coordinates:determine precisely where atelescope was pointed for an image by PlateSolving using Astronomy.netMacro and plugin support:write your own macrosMulti-aperture photometry
ASTRO's 2007 core physics curriculum for radiation oncology residents.

PubMed

Klein, Eric E; Gerbi, Bruce J; Price, Robert A; Balter, James M; Paliwal, Bhudatt; Hughes, Lesley; Huang, Eugene

2007-08-01

In 2004, the American Society for Therapeutic Radiology and Oncology (ASTRO) published a curriculum for physics education. The document described a 54-hour course. In 2006, the committee reconvened to update the curriculum. The committee is composed of physicists and physicians from various residency program teaching institutions. Simultaneously, members have associations with the American Association of Physicists in Medicine, ASTRO, Association of Residents in Radiation Oncology, American Board of Radiology, and American College of Radiology. Representatives from the latter two organizations are key to provide feedback between the examining organizations and ASTRO. Subjects are based on Accreditation Council for Graduate Medical Education requirements (particles and hyperthermia), whereas the majority of subjects and appropriated hours/subject were developed by consensus. The new curriculum is 55 hours, containing new subjects, redistribution of subjects with updates, and reorganization of core topics. For each subject, learning objectives are provided, and for each lecture hour, a detailed outline of material to be covered is provided. Some changes include a decrease in basic radiologic physics, addition of informatics as a subject, increase in intensity-modulated radiotherapy, and migration of some brachytherapy hours to radiopharmaceuticals. The new curriculum was approved by the ASTRO board in late 2006. It is hoped that physicists will adopt the curriculum for structuring their didactic teaching program, and simultaneously, the American Board of Radiology, for its written examination. The American College of Radiology uses the ASTRO curriculum for their training examination topics. In addition to the curriculum, the committee added suggested references, a glossary, and a condensed version of lectures for a Postgraduate Year 2 resident physics orientation. To ensure continued commitment to a current and relevant curriculum, subject matter will be updated
ASTRO's 2007 Core Physics Curriculum for Radiation Oncology Residents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, Eric E.; Gerbi, Bruce J.; Price, Robert A.

2007-08-01

In 2004, American Society for Therapeutic Radiology and Oncology (ASTRO) published a curriculum for physics education. The document described a 54-hour course. In 2006, the committee reconvened to update the curriculum. The committee is composed of physicists and physicians from various residency program teaching institutions. Simultaneously, members have associations with American Association of Physicists in Medicine, ASTRO, Association of Residents in Radiation Oncology, American Board of Radiology, and American College of Radiology. Representatives from the latter two organizations are key to provide feedback between the examining organizations and ASTRO. Subjects are based on Accreditation Council for Graduate Medical Education requirementsmore » (particles and hyperthermia), whereas the majority of subjects and appropriated hours/subject were developed by consensus. The new curriculum is 55 hours, containing new subjects, redistribution of subjects with updates, and reorganization of core topics. For each subject, learning objectives are provided, and for each lecture hour, a detailed outline of material to be covered is provided. Some changes include a decrease in basic radiologic physics, addition of informatics as a subject, increase in intensity-modulated radiotherapy, and migration of some brachytherapy hours to radiopharmaceuticals. The new curriculum was approved by the ASTRO board in late 2006. It is hoped that physicists will adopt the curriculum for structuring their didactic teaching program, and simultaneously, American Board of Radiology, for its written examination. American College of Radiology uses the ASTRO curriculum for their training examination topics. In addition to the curriculum, the committee added suggested references, a glossary, and a condensed version of lectures for a Postgraduate Year 2 resident physics orientation. To ensure continued commitment to a current and relevant curriculum, subject matter will be updated again in 2
Expert Images for All Audiences: The AstroPix Archive

NASA Astrophysics Data System (ADS)

Hurt, Robert; Llamas, Jacob; Wyatt, Ryan Jason; Christensen, Lars

2018-01-01

The AstroPix project provides one-stop-shopping for an extensive collection of the finest astronomical imagery, sourced from some of the world’s most prominent observatories. The archive is made possible by a grassroots effort to tag publicly-released imagery using the Astronomical Visualization Metadata (AVM) standard, which captures rich contextual information for each image. While the site has been in development for many years, it is now supported under NASA’s Universe of Learning collaboration, and AstroPix has been updated and deployed to cloud services. The AVM tags provide many unique features including spectral color assignments, sky context (using AAS WorldWide Telescope APIs), and direct links to the original source material on the web. The 7,000+ assets currently include imagery provided by Chandra, ESO, GALEX, Herschel, Hubble, NuSTAR, Spitzer, and WISE. The assets are also provided for use in the planetarium community by supporting the Data2Dome (D2D) initiative. AstroPix imagery is designed to be used in a variety of unique ways that benefit formal and informal education as well as astronomers and the general public. Observatories can add their own image archives to AstroPix by tagging their assets and providing a simple XML feed, increasing the value of their data to the community at large.

Astrobites: The Astro-ph Reader's Digest For Undergraduates

NASA Astrophysics Data System (ADS)

Kohler, Susanna; Astrobites Team

2013-04-01

Astrobites (http://astrobites.com) is a daily blog aimed primarily at undergraduates interested in astrophysical research and written by a team of graduate students located at diverse institutions around the world. Nearly every day we present a journal article recently posted to astro-ph in a brief format that is accessible to anyone with a general background in the physical sciences. In addition to summarizing new work, Astrobites provides valuable context for readers not yet familiar with the astrophysical literature. Special posts offer career guidance for undergraduates (e.g. applying for an NSF graduate fellowship) and describe personal experiences (e.g. attending an astronomy summer school). We will discuss the Astrobites format and recent readership statistics, as well as potential methods for incorporating Astrobites into the classroom.
Impact of Improved Heat Sinking of an X-Ray Calorimeter Array on Crosstalk, Noise, and Background Events

NASA Technical Reports Server (NTRS)

Kilbourne, C. A.; Adams, J. S.; Brekosky, R. P.; Chervenak, J. A.; Chiao, M. P.; Kelley, R. L.; Kelly, D. P.; Porter, F. S.

2011-01-01

The x-ray calorimeter array of the Soft X-ray Spectrometer (SXS) of the Astro-H satellite will incorporate a silicon thermistor array produced during the development of the X-Ray Spectrometer (XRS) of the Suzaku satellite. On XRS, inadequate heat sinking of the array led to several non-ideal effects. The thermal crosstalk, while too small to be confused with x-ray signals, nonetheless contributed a noise term that could be seen as a degradation in energy resolution at high flux. When energy was deposited in the silicon frame around the active elements of the array, such as by a cosmic ray, the resulting pulse in the temperature of the frame resulted in coincident signal pulses on most of the pixels. In orbit, the resolution was found to depend on the particle background rate. In order to minimize these effects on SXS, heat-sinking gold was applied to areas on the front and back of the array die, which was thermally anchored to the gold of its fanout board via gold wire bonds. The thermal conductance from the silicon chip to the fanout board was improved over that of XRS by an order of magnitude. This change was sufficient for essentially eliminating frame events and allowing high-resolution to be attained at much higher counting rates. We will present the improved performance, the measured crosstalk, and the results of the thermal characterization of such arrays.
Progress report on the Astro-H Soft X-Ray Spectrometer

NASA Astrophysics Data System (ADS)

Kelley, Richard L.; Mitsuda, Kazuhisa

2016-04-01

We describe the initial in-orbit operations and performance of the Astro-H Soft X-Ray Spectrometer (SXS). Astro-H, JAXA's sixth X-ray observatory, is scheduled for launch on February 12, 2016, from the Tanegashima Space Center in Japan abord an H-IIA rocket. The instrument is based on a 36-pixel array of microcalorimeters designed for high resolution over the 0.3-12 keV energy band at the focus of a high throughput, grazing-incidence x-ray mirror. The instrument is the result of a joint collaboration between the JAXA Institute of Space and Astronautical Science and many partners in Japan, and the NASA/Goddard Space Flight Center and collaborators in the US. The principal components of the spectrometer are the microcalorimeter detector system, a low-temperature anticoincidence detector, a 3-stage adiabatic demagnetization refrigerator (ADR) to maintain 50 mK operation under both cryogen and cryogen-free operation, a hybrid liquid helium/cryogen-free dewar with both Stirling and Joule-Thomson coolers, electronics for reading out the array, processing the x-ray data for spectroscopy, and operating the ADR and cryocoolers. The dewar is closed out by an aperture system with five thin-film filters designed to provide high x-ray transmission with low heat loads to the dewar and detector system, and prevent contamination from condensing on the filters. The instrument was designed to have better than 7 eV energy resolution, and was demonstrated to achieve 4-5 eV resolution across the array at the full spacecraft level of integration during extensive ground testing prior to launch. The overall cooling chain has been designed to provide a lifetime of at least 3 years in orbit, and continue to operate without liquid helium to provide redundancy and the longest operational lifetime for the instrument. In this presentation, we will describe the early phases of the SXS instrument in orbit and provide a sense of the astronomical results that can be expected. This presentation is
ASTRO-2 Spacelab Instrument Pointing System mission performance

NASA Technical Reports Server (NTRS)

Wessling, Francis C., III; Singh, S. P.

1995-01-01

This paper reports the performance of the Instrument Pointing System (IPS) that flew on the National Aeronautics and Space Administration (NASA) ASTRO-2 Spacelab mission aboard the Space Shuttle Endeavour in March 1995. The IPS provides a stabilizing platform for the ASTRO-2 instrument payload complement that consists of three main experiments (telescopes). The telescopes observe stellar targets in the universe within the ultraviolet portion of the electromagnetic spectrum that must be observed from beyond the earth's atmospheric filtering effects. The three main experiments for observation are the Hopkins Ultraviolet Telescope (HUT), the Ultraviolet Imaging Telescope (UIT), and the Wisconsin Ultraviolet Photo-Polarimetry Experiment (WUPPE). The HUT uses spectroscopy to obtain the structure and chemical makeup of ultraviolet targets. UIT is responsible for wide field photographing to capture the hidden view of the ultraviolet universe. The WUPPE gathers data on the polarization of the ultraviolet electromagnetic energy coming from the astronomical targets. The capability of IPS enables the experiments to 'see' faint celestial objects. A brief explanation of the IPS is given followed by a review of engineering efforts to improve IPS performance over the ASTRO-1 mission. The main focus of improvements was on enhancing the star acquisition capability through improved guide star selection, lab simulations, computer upgrades, data display systems improvements, and software modifications. A star simulator was developed in the lab to enable IPS to be simulated on the ground pre-mission with flight hardware and software in the loop. The paper concludes with results from the ASTRO-2 mission. The number of targets acquired and the IPS pointing accuracy/stability is reported along with recommendations for the future use of the Instrument Pointing System.
AstroVis: Visualizing astronomical data cubes

NASA Astrophysics Data System (ADS)

Finniss, Stephen; Tyler, Robin; Questiaux, Jacques

2016-08-01

AstroVis enables rapid visualization of large data files on platforms supporting the OpenGL rendering library. Radio astronomical observations are typically three dimensional and stored as data cubes. AstroVis implements a scalable approach to accessing these files using three components: a File Access Component (FAC) that reduces the impact of reading time, which speeds up access to the data; the Image Processing Component (IPC), which breaks up the data cube into smaller pieces that can be processed locally and gives a representation of the whole file; and Data Visualization, which implements an approach of Overview + Detail to reduces the dimensions of the data being worked with and the amount of memory required to store it. The result is a 3D display paired with a 2D detail display that contains a small subsection of the original file in full resolution without reducing the data in any way.
AstroCom NYC: Expanding the Partnership

NASA Astrophysics Data System (ADS)

Paglione, Timothy; Ford, Saavik; Agueros, Marcel A.; Mac Low, Mordecai-Mark; Robbins, Dennis

2015-01-01

AstroCom NYC is an undergraduate mentoring program designed to improve urban minority student access to opportunities in astrophysical research by greatly enhancing partnerships between research astronomers in New York City (City University of New York - an MSI, American Museum of Natural History, and Columbia). AstroCom NYC provides centralized, personalized mentoring as well as financial and academic support, to CUNY undergraduates throughout their studies, plus the resources and opportunities to further CUNY faculty research with students. The goal is that students' residency at AMNH helps them build a sense of belonging in the field, and readies and inspires them for graduate study. AstroCom NYC provides a rigorous Methods of Scientific Research course developed specifically to this purpose, a laptop, research and career mentors, outreach activities, scholarships and stipends, Metrocards, and regular assessment for maximum effectiveness. Stipends in part alleviate the burdens at home typical for CUNY students so they may concentrate on their academic success. AMNH serves as the central hub for our faculty and students, who are otherwise dispersed among all five boroughs of the City. For our second cohort, we dramatically improved the application and screening process, implemented a number of tools to evaluate their potential for grad school, and began growing a network of potential hosts for summer internships around NY State and the US. We review these implementations and outcomes, as well as plans for Year 3, when we expect many of our current students to compete for external summer REUs, and after greatly expanding the program reach through a NASA community college initiative.
AstroCloud: An Agile platform for data visualization and specific analyzes in 2D and 3D

NASA Astrophysics Data System (ADS)

Molina, F. Z.; Salgado, R.; Bergel, A.; Infante, A.

2017-07-01

Nowadays, astronomers commonly run their own tools, or distributed computational packages, for data analysis and then visualizing the results with generic applications. This chain of processes comes at high cost: (a) analyses are manually applied, they are therefore difficult to be automatized, and (b) data have to be serialized, thus increasing the cost of parsing and saving intermediary data. We are developing AstroCloud, an agile visualization multipurpose platform intended for specific analyses of astronomical images (https://astrocloudy.wordpress.com). This platform incorporates domain-specific languages which make it easily extensible. AstroCloud supports customized plug-ins, which translate into time reduction on data analysis. Moreover, it also supports 2D and 3D rendering, including interactive features in real time. AstroCloud is under development, we are currently implementing different choices for data reduction and physical analyzes.
Fluid-loading solutions and plasma volume: Astro-ade and salt tablets with water

NASA Technical Reports Server (NTRS)

Fortney, Suzanne M.; Seinmann, Laura; Young, Joan A.; Hoskin, Cherylynn N.; Barrows, Linda H.

1994-01-01

Fluid loading with salt and water is a countermeasure used after space flight to restore body fluids. However, gastrointestinal side effects have been frequently reported in persons taking similar quantities of salt and water in ground-based studies. The effectiveness of the Shuttle fluid-loading countermeasure (8 gms salt, 0.97 liters of water) was compared to Astro-ade (an isotonic electrolyte solution), to maintain plasma volume (PV) during 4.5 hrs of resting fluid restriction. Three groups of healthy men (n=6) were studied: a Control Group (no drinking), an Astro-ade Group, and a Salt Tablet Group. Changes in PV after drinking were calculated from hematocrit and hemoglobin values. Both the Salt Tablet and Astro-ade Groups maintained PV at 2-3 hours after ingestion compared to the Control Group, which had a 6 percent decline. Side effects (thirst, stomach cramping, and diarrhea) were noted in at least one subject in both the Astro-ade and Salt Tablet Groups. Nausea and vomiting were reported in one subject in the Salt Tablet Group. It was concluded that Astro-ade may be offered as an alternate fluid-loading countermeasure but further work is needed to develop a solution that is more palatable and has fewer side effects.
Updates from Astrobites: The Astro-ph Reader's Digest

NASA Astrophysics Data System (ADS)

Montet, Benjamin; Chisari, N.; Donaldson, J.; Dressing, C. D.; Drout, M.; Faesi, C.; Fuchs, J. T.; Kohler, S.; Lovegrove, E.; Mills, E. A.; Nesvold, E.; Newton, E. R.; Olmstead, A.; Vasel, J. A.; Weiss, L. M.; Astrobites Team

2014-01-01

Astrobites (http://astrobites.com) is a daily blog aimed at undergraduates interested in astrophysical research and written by a team of graduate students located at diverse institutions across the United States. Primarily, we present journal articles recently posted to astro-ph in a brief format that is accessible to anyone with a general background in the physical sciences, including readers who are not yet familiar with the astrophysical literature. Special posts offer career guidance for undergraduates (e.g. applying for an NSF graduate fellowship) and describe personal experiences (e.g. attending an astronomy summer school). We present recent readership statistics and potential methods for incorporating Astrobites into the classroom. We also discuss the Astrobites format across multiple social media platforms, including the newly launched Astroplots, and highlight our recent work organizing the annual "Communicating Science" workshop for graduate students.
Ground-based x-ray calibration of the Astro-H/Hitomi soft x-ray telescopes

NASA Astrophysics Data System (ADS)

Iizuka, Ryo; Hayashi, Takayuki; Maeda, Yoshitomo; Ishida, Manabu; Tomikawa, Kazuki; Sato, Toshiki; Kikuchi, Naomichi; Okajima, Takashi; Soong, Yang; Serlemitsos, Peter J.; Mori, Hideyuki; Izumiya, Takanori; Minami, Sari

2018-01-01

We present the summary of the on-ground calibration of two soft x-ray telescopes (SXT-I and SXT-S), developed by NASA's Goddard Space Flight Center (GSFC), onboard Astro-H/Hitomi. After the initial x-ray measurements with a diverging beam at the GSFC 100-m beamline, we performed the full calibration of the x-ray performance, using the 30-m x-ray beamline facility at the Institute of Space and Astronautical Science of Japan Aerospace Exploration Agency in Japan. We adopted a raster scan method with a narrow x-ray pencil beam with a divergence of ˜15″. The on-axis effective area (EA), half-power diameter, and vignetting function were measured at several energies between 1.5 and 17.5 keV. The detailed results appear in tables and figures in this paper. We measured and evaluated the performance of the SXT-S and the SXT-I with regard to the detector-limited field-of-view and the pixel size of the paired flight detector, i.e., SXS and the SXI, respectively. The primary items measured are the EA, image quality, and stray light for on-axis and off-axis sources. The accurate measurement of these parameters is vital to make the precise response function of the ASTRO-H SXTs. This paper presents the definitive results of the ground-based calibration of the ASTRO-H SXTs.
Astro Talk in Social Media - Indonesia

NASA Astrophysics Data System (ADS)

Yamani, A.; Soegijoko, W.

2015-03-01

Social media is a new trend in communicating and connecting to people. It is also a good choice to build awareness of astronomy as issues spread easily and quickly, creating hot topics. This paper will analyze the trend of astro talk in Indonesia and hope to inspire astronomers to use social media in raising awareness.
50 Years of the Astro-Science Workshop at the Adler Planetarium

NASA Astrophysics Data System (ADS)

Hammergren, Mark; Martynowycz, M. W.; Ratliff, G.

2014-01-01

Since 1964, the Adler Planetarium has hosted a program for highly motivated and interested high-school students known as the Astro-Science Workshop (ASW). Created in response to the national “call to arms” for improved science education following the stunning launch of Sputnik, ASW was originally conducted as an extracurricular astronomy class on Saturday mornings throughout the school year, for many years under the leadership of Northwestern University professor J. Allen Hynek. A gradual decline in student interest in the 1990’s led to a redesign of ASW as a summer program featuring hands-on, student-driven investigation and experimentation. Since 2002, ASW has been organized and taught by graduate student “scientist-educators” and funded through a series of grants from the NSF. For the past seven years, students have designed, built, and flown experiments on helium balloons to altitudes of around 30 km (100,000 feet). Here, as we enter its 50th anniversary, we present the history of the Astro-Science Workshop, its context among the small but still vibrant community of post-Sputnik science enrichment programs, and its rich legacy of inspiring generations of astronomers and other explorers.
VLBI2010: The Astro-Geo Connection

NASA Technical Reports Server (NTRS)

Porcas, Richard

2010-01-01

VLBI2010 holds out promise for greatly increased precision in measuring geodetic and Earth rotation parameters. As a by-product there will be a wealth of interesting new astronomical data. At the same time, astronomical knowledge may be needed to disentangle the astronomical and geodetic contributions to the measured delays and phases. This presentation explores this astro-geo link.
FTS: Fourier transform spectrometer onboard ASTRO-F/FIS

NASA Astrophysics Data System (ADS)

Takahashi, Hidenori; Kawada, Mitsunobu; Murakami, Noriko; Ozawa, Keita; Shibai, Hiroshi; Nakagawa, Takao

2003-03-01

Far-Infrared Surveyor (FIS) is one of the two focal plane instruments of ASTRO-F which is a Japanese infrared astronomical satellite and is planned to launch in 2004. The FIS has spectroscopic capability by a Fourier transform spectrometer (FTS) covering 50-200cm-1 with spectral resolution of 0.2-0.33 cm-1 in addition to the primary purpose of FIS (an all-sky photometric survey). The Martin-Puplett interferometer is adopted as the method for spectroscopy in order to achieve high optical efficiency in a wide wavelength range. The most important issue of the FTS is the development of driving mechanism in order to scan a moving mirror with high optical performances. By the present we succeed to develop the driving mechanism satisfying a lot of limitations and requirements as a instrument onboard satellite. Furthermore the wire-grid polarizers are evaluated in optical performance, these are usable for polarized interferomter. We also measure FIR spectrum using Spectroscopy mode of FIS, and many absorption lines of H2O are detected on continuum spectrum of atmosphere. And the interferogram and spectrum are derived at low temperature (2K) that is practically used in space. The spectrum resembles expected one which are considered with optical components for flight model. The detection limit are estimated combining performances of optical components and detectors, the FISP has sufficient performance to archive objective sciences. FTS will provide a lot of astronomical information; determination of the SED in high-z objects detected by the survey observation of ASTRO-F, the redshift of such objects, and the physical conditions that are hard to be derived by optical/NIR-MIR observations, from FIR lines.
AstroML: "better, faster, cheaper" towards state-of-the-art data mining and machine learning

NASA Astrophysics Data System (ADS)

Ivezic, Zeljko; Connolly, Andrew J.; Vanderplas, Jacob

2015-01-01

We present AstroML, a Python module for machine learning and data mining built on numpy, scipy, scikit-learn, matplotlib, and astropy, and distributed under an open license. AstroML contains a growing library of statistical and machine learning routines for analyzing astronomical data in Python, loaders for several open astronomical datasets (such as SDSS and other recent major surveys), and a large suite of examples of analyzing and visualizing astronomical datasets. AstroML is especially suitable for introducing undergraduate students to numerical research projects and for graduate students to rapidly undertake cutting-edge research. The long-term goal of astroML is to provide a community repository for fast Python implementations of common tools and routines used for statistical data analysis in astronomy and astrophysics (see http://www.astroml.org).
Seeing in a new light: Astro-1 teacher's guide with activities

NASA Technical Reports Server (NTRS)

1990-01-01

A teacher's guide that concentrates on the electromagnetic spectrum is presented. The subject was chosen because it is part of the middle school curriculum and because an understanding of the different ranges of energy is crucial to an understanding of the high energy astronomy performed by the Astro-1 telescopes to be carried on the Space Shuttle's first astrophysics mission. Various learning activities are outlined.
AstroCloud, a Cyber-Infrastructure for Astronomy Research: Architecture

NASA Astrophysics Data System (ADS)

Xiao, J.; Yu, C.; Cui, C.; He, B.; Li, C.; Fan, D.; Hong, Z.; Yin, S.; Wang, C.; Cao, Z.; Fan, Y.; Li, S.; Mi, L.; Wan, W.; Wang, J.; Zhang, H.

2015-09-01

AstroCloud is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences). The ultimate goal of this project is to provide a comprehensive end-to-end astronomy research environment where several independent systems seamlessly collaborate to support the full lifecycle of the modern observational astronomy based on big data, from proposal submission, to data archiving, data release, and to in-situ data analysis and processing. In this paper, the architecture and key designs of the AstroCloud platform are introduced, including data access middleware, access control and security framework, extendible proposal workflow, and system integration mechanism.
Soft gamma-ray detector (SGD) onboard the ASTRO-H mission

NASA Astrophysics Data System (ADS)

Fukazawa, Yasushi; Tajima, Hiroyasu; Watanabe, Shin; Blandford, Roger; Hayashi, Katsuhiro; Harayama, Atsushi; Kataoka, Jun; Kawaharada, Madoka; Kokubun, Motohide; Laurent, Philippe; Lebrun, François; Limousin, Olivier; Madejski, Grzegorz M.; Makishima, Kazuo; Mizuno, Tsunefumi; Mori, Kunishiro; Nakamori, Takeshi; Nakazawa, Kazuhiro; Noda, Hirofumi; Odaka, Hirokazu; Ohno, Masanori; Ohta, Masayuki; Saito, Shin'ya; Sato, Goro; Sato, Rie; Takeda, Shin'ichiro; Takahashi, Hiromitsu; Takahashi, Tadayuki; Tanaka, Yasuyuki; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Yamaoka, Kazutaka; Yatsu, Yoichi; Yonetoku, Daisuke; Yuasa, Takayuki

2014-07-01

The Soft Gamma-ray Detector (SGD) is one of observational instruments onboard the ASTRO-H, and will provide 10 times better sensitivity in 60{600 keV than the past and current observatories. The SGD utilizes similar technologies to the Hard X-ray Imager (HXI) onboard the ASTRO-H. The SGD achieves low background by constraining gamma-ray events within a narrow field-of-view by Compton kinematics, in addition to the BGO active shield. In this paper, we will present the results of various tests using engineering models and also report the flight model production and evaluations.
Soft gamma-ray detector for the ASTRO-H Mission

NASA Astrophysics Data System (ADS)

Watanabe, Shin; Tajima, Hiroyasu; Fukazawa, Yasushi; Blandford, Roger; Enoto, Teruaki; Kataoka, Jun; Kawaharada, Madoka; Kokubun, Motohide; Laurent, Philippe; Lebrun, François; Limousin, Olivier; Madejski, Greg; Makishima, Kazuo; Mizuno, Tsunefumi; Nakamori, Takeshi; Nakazawa, Kazuhiro; Mori, Kunishiro; Odaka, Hirokazu; Ohno, Masanori; Ohta, Masayuki; Sato, Goro; Sato, Rie; Takeda, Shin'ichiro; Takahashi, Hiromitsu; Takahashi, Tadayuki; Tanaka, Takaaki; Tashiro, Makoto; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Yamada, Shinya; Yatsu, Yoichi; Yonetoku, Daisuke; Yuasa, Takayuki

2012-09-01

ASTRO-H is the next generation JAXA X-ray satellite, intended to carry instruments with broad energy coverage and exquisite energy resolution. The Soft Gamma-ray Detector (SGD) is one of ASTRO-H instruments and will feature wide energy band (60-600 keV) at a background level 10 times better than the current instruments on orbit. The SGD is complimentary to ASTRO-H’s Hard X-ray Imager covering the energy range of 5-80 keV. The SGD achieves low background by combining a Compton camera scheme with a narrow field-of-view active shield where Compton kinematics is utilized to reject backgrounds. The Compton camera in the SGD is realized as a hybrid semiconductor detector system which consists of silicon and CdTe (cadmium telluride) sensors. Good energy resolution is afforded by semiconductor sensors, and it results in good background rejection capability due to better constraints on Compton kinematics. Utilization of Compton kinematics also makes the SGD sensitive to the gamma-ray polarization, opening up a new window to study properties of gamma-ray emission processes. In this paper, we will present the detailed design of the SGD and the results of the final prototype developments and evaluations. Moreover, we will also present expected performance based on the measurements with prototypes.
Astro-H/Hitomi data analysis, processing, and archive

NASA Astrophysics Data System (ADS)

Angelini, Lorella; Terada, Yukikatsu; Dutka, Michael; Eggen, Joseph; Harrus, Ilana; Hill, Robert S.; Krimm, Hans; Loewenstein, Michael; Miller, Eric D.; Nobukawa, Masayoshi; Rutkowski, Kristin; Sargent, Andrew; Sawada, Makoto; Takahashi, Hiromitsu; Yamaguchi, Hiroya; Yaqoob, Tahir; Witthoeft, Michael

2018-01-01

Astro-H is the x-ray/gamma-ray mission led by Japan with international participation, launched on February 17, 2016. Soon after launch, Astro-H was renamed Hitomi. The payload consists of four different instruments (SXS, SXI, HXI, and SGD) that operate simultaneously to cover the energy range from 0.3 keV up to 600 keV. On March 27, 2016, JAXA lost contact with the satellite and, on April 28, they announced the cessation of the efforts to restore mission operations. Hitomi collected about one month's worth of data with its instruments. This paper presents the analysis software and the data processing pipeline created to calibrate and analyze the Hitomi science data, along with the plan for the archive. These activities have been a collaborative effort shared between scientists and software engineers working in several institutes in Japan and United States.

Neutrino nuclear responses for double beta decays and astro neutrinos by charge exchange reactions

NASA Astrophysics Data System (ADS)

Ejiri, Hiroyasu

2014-09-01

Neutrino nuclear responses are crucial for neutrino studies in nuclei. Charge exchange reactions (CER) are shown to be used to study charged current neutrino nuclear responses associated with double beta decays(DBD)and astro neutrino interactions. CERs to be used are high energy-resolution (He3 ,t) reactions at RCNP, photonuclear reactions via IAR at NewSUBARU and muon capture reactions at MUSIC RCNP and MLF J-PARC. The Gamow Teller (GT) strengths studied by CERs reproduce the observed 2 neutrino DBD matrix elements. The GT and spin dipole (SD) matrix elements are found to be reduced much due to the nucleon spin isospin correlations and the non-nucleonic (delta isobar) nuclear medium effects. Impacts of the reductions on the DBD matrix elements and astro neutrino interactions are discussed.
AstroCom NYC: Equity, Inclusion, and the Next Generation of Astrophysicists

NASA Astrophysics Data System (ADS)

Paglione, Timothy; Ford, Saavik; Robbins, Dennis; Agueros, Marcel A.; Mac Low, Mordecai-Mark

2017-01-01

AstroCom NYC is an undergraduate mentoring program designed to improve urban minority student access to opportunities in astrophysical research by greatly enhancing partnerships between research astronomers in New York City (City University of New York - an MSI, American Museum of Natural History, and Columbia). AstroCom NYC provides centralized, personalized mentoring as well as financial and academic support, to CUNY undergraduates throughout their studies, plus the resources and opportunities to further CUNY faculty research with students. The goal is that students’ residency at AMNH helps them build a sense of belonging in the field, and readies and inspires them for graduate study. AstroCom NYC provides a rigorous Methods of Scientific Research course developed specifically to this purpose, a laptop, research and career mentors, outreach activities, scholarships and stipends, Metrocards, and regular assessment for maximum effectiveness. The goal of this support is to remove barriers to access and success. AMNH serves as the central hub for our faculty and students, who are otherwise dispersed among all five boroughs of the City. We welcomed our fourth cohort last year, along with 25 additional students through a NASA community college initiative. Our advanced AstroCom NYC students earned external summer internships at REU sites, and we had our first graduate school acceptance. We review plans for Year 5, when we have a number of graduate school applicants, and our deepening participation and leadership within partner activities.
One Click to the Cosmos: The AstroPix Image Archive

NASA Astrophysics Data System (ADS)

Hurt, Robert L.; Llamas, J.; Squires, G. K.; Brinkworth, C.; X-ray Center, Chandra; ESO/ESA; Science Center, Spitzer; STScI

2013-01-01

Imagine a single website that acts as a portal to the entire wealth of public imagery spanning the world's observatories. This is the goal of the AstroPix project (astropix.ipac.caltech.edu), and you can use it today! Although still in a beta development state, this past year has seen the inclusion of thousands of images spanning some of the most prominent observatories in the world, including Chandra, ESO, Galex, Herschel, Hubble, Spitzer, and WISE, with more on the way. The archive is unique as it is built around the Astronomical Visualization Metadata (AVM) standard, which captures the rich contextual information for each image. This ranges from titles and descriptions, to color representations and observation details, to sky coordinates. AVM enables AstroPix imagery to be used in a variety of unique ways that benefit formal and informal education as well as astronomers and the general public. Visitors to Astropix can search the database using simple free-text queries, or use a structured search (similar to "Smart Playlists" found in iTunes, for example). We are also developing public application programming interfaces (APIs) to allow third party software and websites to access the growing content for a variety of uses (planetarium software, museum kiosks, mobile apps, and creative web interfaces, to name a few). Contributing image assets to AstroPix is as easy as tagging the images with the relevant metadata and including the web links to the images in a simple RSS feed. We will cover some of the latest information about tools to contribute images to AstroPix and ways to use the site.
Astrobites: The Astro-ph Reader's Digest For Undergraduates

NASA Astrophysics Data System (ADS)

Vasel, Justin; Faesi, Chris; Drout, Maria; Newton, Elisabeth

2013-04-01

Astrobites (http://astrobites.com) is a daily blog aimed primarily at undergraduates interested in astrophysical research and written by a team of graduate students located at institutions around the world. Nearly every day we present a journal article recently posted to astro-ph in a brief format that is accessible to anyone with a general background in the physical sciences. In addition to summarizing new work, Astrobites provides valuable context for readers not yet familiar with the some of the background concepts and jargon present in the astrophysical literature. Special posts offer career guidance for undergraduates (e.g. applying for an NSF graduate fellowship) and describe personal experiences (e.g. attending an astronomy summer school). The readership of astrobites has grown dramatically since our founding in fall of 2010, with individuals now accessing the site from 104 countries worldwide. We will discuss the Astrobites format, recent readership statistics, and future planned initiatives.
Astrobites: The Astro-ph Reader's Digest For Undergraduates

NASA Astrophysics Data System (ADS)

Drout, Maria; Vasel, J. A.; Dressing, C. D.; Gifford, D.; Morley, C.; Hall, S.; Newton, E. R.; Astrobites Team

2013-01-01

Astrobites (http://astrobites.com) is a daily blog aimed primarily at undergraduates interested in astrophysical research and written by a team of graduate students located at institutions around the world. Nearly every day we present a journal article recently posted to astro-ph in a brief format that is accessible to anyone with a general background in the physical sciences. In addition to summarizing new work, Astrobites provides valuable context for readers not yet familiar with the some of the background concepts and jargon present in the astrophysical literature. Special posts offer career guidance for undergraduates (e.g. applying for an NSF graduate fellowship) and describe personal experiences (e.g. attending an astronomy summer school). The readership of astrobites has grown dramatically since our founding in fall of 2010, with individuals now accessing the site from 104 countries worldwide. We will discuss the Astrobites format, recent readership statistics, and future planned initiatives.
View of ASTRO-2 payload in cargo bay of STS-67 Endeavour

NASA Image and Video Library

1995-03-17

STS067-713-072 (2-18 March 1995) --- This 70mm cargo bay scene, backdropped against a desert area of Namibia, typifies the view that daily greeted the Astro-2 crew members during their almost 17-days aboard the Space Shuttle Endeavour. Positioned on the Spacelab pallet amidst other hardware, the Astro-2 payload is in its operational mode. Visible here are the Instrument Pointing System (IPS), Hopkins Ultraviolet Telescope (HUT), Star Tracker (ST), Ultraviolet Imaging Telescope (UIT), Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE), and Integrated Radiator System (IRS). At this angle, the Optical Sensor Package (OPS) is not seen. The Igloo, which supports the package of experiments, is in center foreground. Two Get-Away Special (GAS) canisters are in lower left foreground. The Extended Duration Orbiter (EDO) pallet, located aft of the cargo bay, is obscured by the Astro-2 payload. The Endeavour was 190 nautical miles above Earth.
astroABC : An Approximate Bayesian Computation Sequential Monte Carlo sampler for cosmological parameter estimation

NASA Astrophysics Data System (ADS)

Jennings, E.; Madigan, M.

2017-04-01

Given the complexity of modern cosmological parameter inference where we are faced with non-Gaussian data and noise, correlated systematics and multi-probe correlated datasets,the Approximate Bayesian Computation (ABC) method is a promising alternative to traditional Markov Chain Monte Carlo approaches in the case where the Likelihood is intractable or unknown. The ABC method is called "Likelihood free" as it avoids explicit evaluation of the Likelihood by using a forward model simulation of the data which can include systematics. We introduce astroABC, an open source ABC Sequential Monte Carlo (SMC) sampler for parameter estimation. A key challenge in astrophysics is the efficient use of large multi-probe datasets to constrain high dimensional, possibly correlated parameter spaces. With this in mind astroABC allows for massive parallelization using MPI, a framework that handles spawning of processes across multiple nodes. A key new feature of astroABC is the ability to create MPI groups with different communicators, one for the sampler and several others for the forward model simulation, which speeds up sampling time considerably. For smaller jobs the Python multiprocessing option is also available. Other key features of this new sampler include: a Sequential Monte Carlo sampler; a method for iteratively adapting tolerance levels; local covariance estimate using scikit-learn's KDTree; modules for specifying optimal covariance matrix for a component-wise or multivariate normal perturbation kernel and a weighted covariance metric; restart files output frequently so an interrupted sampling run can be resumed at any iteration; output and restart files are backed up at every iteration; user defined distance metric and simulation methods; a module for specifying heterogeneous parameter priors including non-standard prior PDFs; a module for specifying a constant, linear, log or exponential tolerance level; well-documented examples and sample scripts. This code is hosted
ASTROS: A multidisciplinary automated structural design tool

NASA Technical Reports Server (NTRS)

Neill, D. J.

1989-01-01

ASTROS (Automated Structural Optimization System) is a finite-element-based multidisciplinary structural optimization procedure developed under Air Force sponsorship to perform automated preliminary structural design. The design task is the determination of the structural sizes that provide an optimal structure while satisfying numerous constraints from many disciplines. In addition to its automated design features, ASTROS provides a general transient and frequency response capability, as well as a special feature to perform a transient analysis of a vehicle subjected to a nuclear blast. The motivation for the development of a single multidisciplinary design tool is that such a tool can provide improved structural designs in less time than is currently needed. The role of such a tool is even more apparent as modern materials come into widespread use. Balancing conflicting requirements for the structure's strength and stiffness while exploiting the benefits of material anisotropy is perhaps an impossible task without assistance from an automated design tool. Finally, the use of a single tool can bring the design task into better focus among design team members, thereby improving their insight into the overall task.
Cure-WISE: HETDEX data reduction with Astro-WISE

NASA Astrophysics Data System (ADS)

Snigula, J. M.; Cornell, M. E.; Drory, N.; Fabricius, Max.; Landriau, M.; Hill, G. J.; Gebhardt, K.

2012-09-01

The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) is a blind spectroscopic survey to map the evolution of dark energy using Lyman-alpha emitting galaxies at redshifts 1:9 < z < 3:5 as tracers. The survey instrument, VIRUS, consists of 75 IFUs distributed across the 22-arcmin field of the upgraded 9.2-m HET. Each exposure gathers 33,600 spectra. Over the projected five year run of the survey we expect about 170 GB of data per night. For the data reduction we developed the Cure pipeline. Cure is designed to automatically find and calibrate the observed spectra, subtract the sky background, and detect and classify different types of sources. Cure employs rigorous statistical methods and complete pixel-level error propagation throughout the reduction process to ensure Poisson-limited performance and meaningful significance values. To automate the reduction of the whole dataset we implemented the Cure pipeline in the Astro-WISE framework. This integration provides for HETDEX a database backend with complete dependency tracking of the various reduction steps, automated checks, and a searchable interface to the detected sources and user management. It can be used to create various web interfaces for data access and quality control. Astro-WISE allows us to reduce the data from all the IFUs in parallel on a compute cluster. This cluster allows us to reduce the observed data in quasi real time and still have excess capacity for rerunning parts of the reduction. Finally, the Astro-WISE interface will be used to provide access to reduced data products to the general community.
Astro Camp is a blast!

NASA Image and Video Library

2006-06-08

An Astro Camp counselor and her campers perform a science experiment to learn what types of `fuel' will best propel their 'rockets.' Stennis Space Center's popular series of day camps have campers design, build and test model rockets based on the principles that would be used to build different types of rockets suitable for a mission to the moon or Mars. They learn details like how far they would travel, how long it would take, what supplies they would need and how to survive in that environment.
Using pedagogical discipline representations (PDRs) to enable Astro 101 students to reason about modern astrophysics

NASA Astrophysics Data System (ADS)

Wallace, Colin Scott; Prather, Edward E.; Chambers, Timothy G.; Kamenetzky, Julia R.; Hornstein, Seth D.

2017-01-01

Instructors of introductory, college-level, general education astronomy (Astro 101) often want to include topics from the cutting-edge of modern astrophysics in their course. Unfortunately, the teaching of these cutting-edge topics is typically confined to advanced undergraduate or graduate classes, using representations (graphical, mathematical, etc.) that are inaccessible to the vast majority of Astro 101 students. Consequently, many Astro 101 instructors feel that they have no choice but to cover these modern topics at a superficial level. Pedagogical discipline representations (PDRs) are one solution to this problem. Pedagogical discipline representations are representations that are explicitly designed to enhance the teaching and learning of a topic, even though these representations may not typically be found in traditional textbooks or used by experts in the discipline who are engaged in topic-specific discourse. In some cases, PDRs are significantly simplified or altered versions of typical discipline representations (graphs, data tables, etc.); in others they may be novel and highly contextualized representations with unique features that purposefully engage novice learners’ pre-existing mental models and reasoning difficulties, facilitating critical discourse. In this talk, I will discuss important lessons that my colleagues and I have learned while developing PDRs and describe how PDRs can enable students to reason about complex modern astrophysical topics.
AstroBlend: An astrophysical visualization package for Blender

NASA Astrophysics Data System (ADS)

Naiman, J. P.

2016-04-01

The rapid growth in scale and complexity of both computational and observational astrophysics over the past decade necessitates efficient and intuitive methods for examining and visualizing large datasets. Here, I present AstroBlend, an open-source Python library for use within the three dimensional modeling software, Blender. While Blender has been a popular open-source software among animators and visual effects artists, in recent years it has also become a tool for visualizing astrophysical datasets. AstroBlend combines the three dimensional capabilities of Blender with the analysis tools of the widely used astrophysical toolset, yt, to afford both computational and observational astrophysicists the ability to simultaneously analyze their data and create informative and appealing visualizations. The introduction of this package includes a description of features, work flow, and various example visualizations. A website - www.astroblend.com - has been developed which includes tutorials, and a gallery of example images and movies, along with links to downloadable data, three dimensional artistic models, and various other resources.
Astro4Girls and Their Families: Sharing Science via Public Libraries

NASA Astrophysics Data System (ADS)

Sharma, M.; Smith, D.; Eisenhamer, B.; Ryer, H.; Dussault, M.; Braswell, E.; Cominsky, L.; Apple, N.; Della, T.; Whiffen, P.; Harman, P.; Mitchell, S.; Eyermann, S.; Brandehoff, S.; Dominiak, J.

2013-04-01

The “Astro4Girls and Their Families” pilot program offered a variety of informal science events at nine public libraries nationwide in conjunction with Women's History Month (March) 2012. The goals were to engage girls and their families in science, by helping them discover the Universe for themselves and celebrating the contribution of women to astronomy and science. We offered a wide range of activities, from using robotic telescopes for “Do-It-Yourself (DIY) astrophotography” to making edible black holes, to exploring the infrared Universe. Our main target audience was middle-school aged girls, but students of all ages, their families and the public were welcome to participate in many of the activities. Five NASA Science Mission Directorate-funded Astrophysics Education and Public Outreach teams partnered with public libraries in this pilot program; each worked with 1 or 2 libraries to offer a total of about 15 events reaching over 300 people in both urban and rural areas. The American Library Association Public Programs Office identified participating libraries and facilitated their participation through its role in the SMD-funded “Visions of the Universe: Four Centuries of Discovery” traveling exhibit. The NASA Astrophysics Science Education and Public Outreach Forum coordinated the collaboration. The website is: http://www.ala.org/programming/astro4girls. This poster outlines the details of planning and implementing the 2012 pilot program, its successes, and lessons learned. The collaborators would like to engage the EPO community in a discussion of how to sustain Astro4Girls and engage additional public libraries nationwide during future Women's History Months.
The HEASARC in 2013 and Beyond: NuSTAR, Astro-H, NICER..

NASA Astrophysics Data System (ADS)

Drake, Stephen A.; Smale, A. P.; McGlynn, T. A.; Arnaud, K. A.

2013-04-01

The High Energy Astrophysics Archival Research Center or HEASARC (http://heasarc.gsfc.nasa.gov/) is in its third decade as the NASA astrophysics discipline node supporting multi-mission cosmic X-ray and gamma-ray astronomy research. It provides a unified archive and software structure aimed both at 'legacy' missions such as Einstein, EXOSAT, ROSAT and RXTE, contemporary missions such as Fermi, Swift, Suzaku, Chandra, etc., and upcoming missions, such as NuSTAR, Astro-H and NICER. The HEASARC's high-energy astronomy archive has grown so that it presently contains 45 TB of data from 28 orbital missions. The HEASARC is the designated archive which supports NASA's Physics of the Cosmos theme (http://pcos.gsfc.nasa.gov/). We discuss some of the upcoming new initiatives and developments for the HEASARC, including the arrival of public data from the hard X-ray imaging NuSTAR mission in the summer of 2013, and the ongoing preparations to support the JAXA/NASA Astro-H mission and the NASA MoO Neutron Star Interior Composition Explorer (NICER), which are expected to become operational in 2015-2016. We also highlight some of the new software capabilities of the HEASARC, such as Xamin, a next-generation archive interface which will eventually supersede Browse, and the latest update of XSPEC (v 12.8.0).
AstroCom NYC: A National Model for Urban Minority Engagement

NASA Astrophysics Data System (ADS)

Paglione, Timothy; Ford, Saavik; Robbins, Dennis; Mac Low, Mordecai-Mark; Agueros, Marcel A.

2016-01-01

AstroCom NYC is an undergraduate mentoring program designed to improve urban minority student access to opportunities in astrophysical research by greatly enhancing partnerships between research astronomers in New York City (City University of New York - an MSI, American Museum of Natural History, and Columbia). AstroCom NYC provides centralized, personalized mentoring as well as financial and academic support, to CUNY undergraduates throughout their studies, plus the resources and opportunities to further CUNY faculty research with students. The goal is that students' residency at AMNH helps them build a sense of belonging in the field, and readies and inspires them for graduate study. AstroCom NYC provides a rigorous Methods of Scientific Research course developed specifically to this purpose, a laptop, research and career mentors, outreach activities, scholarships and stipends, Metrocards, and regular assessment for maximum effectiveness. The goal of this support is to remove barriers to access and success. AMNH serves as the central hub for our faculty and students, who are otherwise dispersed among all five boroughs of the City. We welcomed our third and largest cohort last year, along with 13 additional students through a NASA community college initiative. We review plans for Year 4, when we expect all of our interns to compete for external summer REUs, and our growing participation and leadership within partner activities.
IAU astroEDU: an open-access platform for peer-reviewed astronomy education activities

NASA Astrophysics Data System (ADS)

Heenatigala, Thilina; Russo, Pedro; Strubbe, Linda; Gomez, Edward

2015-08-01

astroEDU is an open access platform for peer-reviewed astronomy education activities. It addresses key problems in educational repositories such as variability in quality, not maintained or updated regularly, limited content review, and more. This is achieved through a peer-review process similar to what scholarly articles are based on. Activities submitted are peer-reviewed by an educator and a professional astronomer which gives the credibility to the activities. astroEDU activities are open-access in order to make the activities accessible to educators around the world while letting them discover, review, distribute and remix the activities. The activity submission process allows authors to learn how to apply enquiry-based learning into the activity, identify the process skills required, how to develop core goals and objectives, and how to evaluate the activity to determine the outcome. astroEDU is endorsed by the International Astronomical Union meaning each activity is given an official stamp by the international organisation for professional astronomers.
MAPPING THE GAS TURBULENCE IN THE COMA CLUSTER: PREDICTIONS FOR ASTRO-H

DOE Office of Scientific and Technical Information (OSTI.GOV)

ZuHone, J. A.; Markevitch, M.; Zhuravleva, I.

2016-02-01

Astro-H will be able for the first time to map gas velocities and detect turbulence in galaxy clusters. One of the best targets for turbulence studies is the Coma cluster, due to its proximity, absence of a cool core, and lack of a central active galactic nucleus. To determine what constraints Astro-H will be able to place on the Coma velocity field, we construct simulated maps of the projected gas velocity and compute the second-order structure function, an analog of the velocity power spectrum. We vary the injection scale, dissipation scale, slope, and normalization of the turbulent power spectrum, andmore » apply measurement errors and finite sampling to the velocity field. We find that even with sparse coverage of the cluster, Astro-H will be able to measure the Mach number and the injection scale of the turbulent power spectrum—the quantities determining the energy flux down the turbulent cascade and the diffusion rate for everything that is advected by the gas (metals, cosmic rays, etc.). Astro-H will not be sensitive to the dissipation scale or the slope of the power spectrum in its inertial range, unless they are outside physically motivated intervals. We give the expected confidence intervals for the injection scale and the normalization of the power spectrum for a number of possible pointing configurations, combining the structure function and velocity dispersion data. Importantly, we also determine that measurement errors on the line shift will bias the velocity structure function upward, and show how to correct this bias.« less
Mapping the Gas Turbulence in the Coma Cluster: Predictions for Astro-H

NASA Technical Reports Server (NTRS)

ZuHone, J. A.; Markevitch, M.; Zhuravleva, I.

2016-01-01

Astro-H will be able for the first time to map gas velocities and detect turbulence in galaxy clusters. One of the best targets for turbulence studies is the Coma cluster, due to its proximity, absence of a cool core, and lack of a central active galactic nucleus. To determine what constraints Astro-H will be able to place on the Coma velocity field, we construct simulated maps of the projected gas velocity and compute the second-order structure function, an analog of the velocity power spectrum. We vary the injection scale, dissipation scale, slope, and normalization of the turbulent power spectrum, and apply measurement errors and finite sampling to the velocity field. We find that even with sparse coverage of the cluster, Astro-H will be able to measure the Mach number and the injection scale of the turbulent power spectrum-the quantities determining the energy flux down the turbulent cascade and the diffusion rate for everything that is advected by the gas (metals, cosmic rays, etc.). Astro-H will not be sensitive to the dissipation scale or the slope of the power spectrum in its inertial range, unless they are outside physically motivated intervals. We give the expected confidence intervals for the injection scale and the normalization of the power spectrum for a number of possible pointing configurations, combining the structure function and velocity dispersion data. Importantly, we also determine that measurement errors on the line shift will bias the velocity structure function upward, and show how to correct this bias.
X-ray Raman spectroscopic study of benzene at high pressure.

PubMed

Pravica, Michael; Grubor-Urosevic, Ognjen; Hu, Michael; Chow, Paul; Yulga, Brian; Liermann, Peter

2007-10-11

We have used X-ray Raman spectroscopy (XRS) to study benzene up to approximately 20 GPa in a diamond anvil cell at ambient temperature. The experiments were performed at the High-Pressure Collaborative Access Team's 16 ID-D undulator beamline at the Advanced Photon Source. Scanned monochromatic X-rays near 10 keV were used to probe the carbon X-ray edge near 284 eV via inelastic scattering. The diamond cell axis was oriented perpendicular to the X-ray beam axis to prevent carbon signal contamination from the diamonds. Beryllium gaskets confined the sample because of their high transmission throughput in this geometry. Spectral alterations with pressure indicate bonding changes that occur with pressure because of phase changes (liquid: phase I, II, III, and III') and possibly due to changes in the hybridization of the bonds. Changes in the XRS spectra were especially evident in the data taken when the sample was in phase III', which may be related to a rate process observed in earlier shock wave studies.
The soft gamma-ray detector (SGD) onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Watanabe, Shin; Tajima, Hiroyasu; Fukazawa, Yasushi; Blandford, Roger; Enoto, Teruaki; Goldwurm, Andrea; Hagino, Kouichi; Hayashi, Katsuhiro; Ichinohe, Yuto; Kataoka, Jun; Katsuta, Junichiro; Kitaguchi, Takao; Kokubun, Motohide; Laurent, Philippe; Lebrun, François; Limousin, Olivier; Madejski, Grzegorz M.; Makishima, Kazuo; Mizuno, Tsunefumi; Mori, Kunishiro; Nakamori, Takeshi; Nakano, Toshio; Nakazawa, Kazuhiro; Noda, Hirofumu; Odaka, Hirokazu; Ohno, Masanori; Ohta, Masayuki; Saito, Shinya; Sato, Goro; Sato, Rie; Takeda, Shin'ichiro; Takahashi, Hiromitsu; Takahashi, Tadayuki; Tanaka, Takaaki; Tanaka, Yasuyuki; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Yamaoka, Kazutaka; Yatsu, Yoichi; Yonetoku, Daisuke; Yuasa, Takayuki

2016-07-01

The Soft Gamma-ray Detector (SGD) is one of science instruments onboard ASTRO-H (Hitomi) and features a wide energy band of 60{600 keV with low backgrounds. SGD is an instrument with a novel concept of "Narrow field-of-view" Compton camera where Compton kinematics is utilized to reject backgrounds which are inconsistent with the field-of-view defined by the active shield. After several years of developments, the flight hardware was fabricated and subjected to subsystem tests and satellite system tests. After a successful ASTRO-H (Hitomi) launch on February 17, 2016 and a critical phase operation of satellite and SGD in-orbit commissioning, the SGD operation was moved to the nominal observation mode on March 24, 2016. The Compton cameras and BGO-APD shields of SGD worked properly as designed. On March 25, 2016, the Crab nebula observation was performed, and, the observation data was successfully obtained.

Cure-WISE: HETDEX Data Reduction with Astro-WISE

NASA Astrophysics Data System (ADS)

Snigula, J. M.; Drory, N.; Fabricius, M.; Landriau, M.; Montesano, F.; Hill, G. J.; Gebhardt, K.; Cornell, M. E.

2014-05-01

The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX, Hill et al. 2012b) is a blind spectroscopic survey to map the evolution of dark energy using Lyman-alpha emitting galaxies at redshifts 1.9< ɀ <3.5 as tracers. The survey will use an array of 75 integral field spectrographs called the Visible Integral field Replicable Unit (IFU) Spectrograph (VIRUS, Hill et al. 2012c). The 10m HET (Ramsey et al. 1998) currently receives a wide-field upgrade (Hill et al. 2012a) to accomodate the spectrographs and to provide the needed field of view. Over the projected five year run of the survey we expect to obtain approximately 170 GB of data each night. For the data reduction we developed the Cure pipeline, to automatically find and calibrate the observed spectra, subtract the sky background, and detect and classify different types of sources. Cure employs rigorous statistical methods and complete pixel-level error propagation throughout the reduction process to ensure Poisson-limited performance and meaningful significance values. To automate the reduction of the whole dataset we implemented the Cure pipeline in the Astro-WISE framework. This integration provides for HETDEX a database backend with complete dependency tracking of the various reduction steps, automated checks, and a searchable interface to the detected sources and user management. It can be used to create various web interfaces for data access and quality control. Astro-WISE allows us to reduce the data from all the IFUs in parallel on a compute cluster. This cluster allows us to reduce the observed data in quasi real time and still have excess capacity for rerunning parts of the reduction. Finally, the Astro-WISE interface will be used to provide access to reduced data products to the general community.
The Evolution of Spacelab Ultraviolet Astronomy Missions from OSS-3 through -7 to Astro-1

NASA Astrophysics Data System (ADS)

Gull, Theodore

2018-01-01

In the 1960s and 1970s, NASA was building towards a robust program in space astronomy. An evolutionary step from ground-based astronomy to space astronomy was human operation of space telescopes as astronomy in general evolved from astronomers directly at the telescope to application of computers and long distance communications to control to operate remote telescopes. Today ground-based telescopes and space observatories from cubesats to the Hubble Space Telescope and soon the James Webb Space Telescope are routinely operated remotely.In response to the Spacelab Announcement of Opportunity in the early 1980s, three ultraviolet experiments – the Hopkins Ultraviolet Telescope, the Ultraviolet Imaging Telescope and the Wisconsin Ultraviolet PhotoPolarimetry Experiment -- all instruments derived from multiple sounding rocket flights--were selected to fly as an integrated payload attached to a space shuttle. The justification for professional astronomers, both as Mission Specialists from the astronaut cadre and Payload Specialists from the instrument teams, was built to ensure key technical skills both of the science and the instruments. Bundled together as OSS-3 through -7 flights focused on Comet Halley, the experiments went through many changes and delays as a pathfinder for an anticipated series of attached astronomy payloads.By 1986, the five-flight mission had evolved into two missions, Astro-1 dedicated primarily to observe Halley’s Comet in early March 1986 and Astro-2 to fly about one year later. Due to the Challenger disaster 35 days before scheduled launch of Astro-1, the mission went through an initial cancellation and then re-scheduling once the instrument complement of Astro-1 was expanded to include Broad Band X-ray Telescope with emphasis on studying SN1987A. Ultimately Astro-1 flew in December 1990 partnered with an X-ray experiment focused on SN1987A.The nine-day mission was mostly successful despite multiple technical issues overcome by the NASA
Ground Calibration of the Astro-H (Hitomi) Soft X-Ray Spectrometer

NASA Technical Reports Server (NTRS)

Eckart, M. E.; Adams, J. S.; Boyce, K. R.; Brown, G. V.; Chiao, Meng P.; Fujimoto, R. J.; Haas, D.; Den Herder, J. W.; Ishisaki, Y.; Kelley, R. L.;

2016-01-01

The Astro-H (Hitomi) Soft X-ray Spectrometer (SXS) was a pioneering imaging x-ray spectrometer with 5 eV energy resolution at 6 keV. The instrument used a microcalorimeter array at the focus of a high-throughput soft x-ray telescope to enable high-resolution non-dispersive spectroscopy in the soft x-ray waveband (0.3-12 keV). We present the suite of ground calibration measurements acquired from 2012-2015, including characterization of the detector system, anti-coincidence detector, optical blocking filters, and filter-wheel filters. The calibration of the 36-pixel silicon thermistor microcalorimeter array includes parameterizations of the energy gain scale and line spread function for each event grade over a range of instrument operating conditions, as well as quantum efficiency measurements. The x-ray transmission of the set of five Al/polyimide thin-film optical blocking filters mounted inside the SXS dewar has been modeled based on measurements at synchrotron beamlines, including with high spectral resolution at the C, N, O, and Al K-edges. In addition, we present the x-ray transmission of the dewar gate valve and of the filters mounted on the SXS filter wheel (external to the dewar), including beryllium, polyimide, and neutral density filters.

Discovery & Interaction in Astro 101 Laboratory Experiments

NASA Astrophysics Data System (ADS)

Maloney, Frank Patrick; Maurone, Philip; DeWarf, Laurence E.

2016-01-01

The availability of low-cost, high-performance computing hardware and software has transformed the manner by which astronomical concepts can be re-discovered and explored in a laboratory that accompanies an astronomy course for arts students. We report on a strategy, begun in 1992, for allowing each student to understand fundamental scientific principles by interactively confronting astronomical and physical phenomena, through direct observation and by computer simulation. These experiments have evolved as :a) the quality and speed of the hardware has greatly increasedb) the corresponding hardware costs have decreasedc) the students have become computer and Internet literated) the importance of computationally and scientifically literate arts graduates in the workplace has increased.We present the current suite of laboratory experiments, and describe the nature, procedures, and goals in this two-semester laboratory for liberal arts majors at the Astro 101 university level.
AstroCloud, a Cyber-Infrastructure for Astronomy Research: Cloud Computing Environments

NASA Astrophysics Data System (ADS)

Li, C.; Wang, J.; Cui, C.; He, B.; Fan, D.; Yang, Y.; Chen, J.; Zhang, H.; Yu, C.; Xiao, J.; Wang, C.; Cao, Z.; Fan, Y.; Hong, Z.; Li, S.; Mi, L.; Wan, W.; Wang, J.; Yin, S.

2015-09-01

AstroCloud is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences). Based on CloudStack, an open source software, we set up the cloud computing environment for AstroCloud Project. It consists of five distributed nodes across the mainland of China. Users can use and analysis data in this cloud computing environment. Based on GlusterFS, we built a scalable cloud storage system. Each user has a private space, which can be shared among different virtual machines and desktop systems. With this environments, astronomer can access to astronomical data collected by different telescopes and data centers easily, and data producers can archive their datasets safely.
Initial Development and Pilot Study Design of Interactive Lecture Demonstrations for ASTRO 101

NASA Astrophysics Data System (ADS)

Schwortz, Andria C.; French, D. A; Gutierrez, Joseph V; Sanchez, Richard L; Slater, Timothy F.; Tatge, Coty

2014-06-01

Interactive lecture demonstrations (ILDs) have repeatedly shown to be effective tools for improving student achievement in the context of learning physics. As a first step toward systematic development of interactive lecture demonstrations in ASTRO 101, the introductory astronomy survey course, a systematic review of education research, describing educational computer simulations (ECSs) reveals that initial development requires a targeted study of how ASTRO 101 students respond to ECSs in the non-science majoring undergraduate lecture setting. In this project we have adopted the process by which ILDs were designed, pilot-tested, and successfully implemented in the context of physics teaching (Sokoloff & Thornton, 1997; Sokoloff & Thornton, 2004). We have designed the initial pilot-test set of ASTRO 101 ILD instructional materials relying heavily on ECSs. Both an instructor’s manual and a preliminary classroom-ready student workbook have been developed, and we are implementing a pilot study to explore their effectiveness in communicating scientific content, and the extent to which they might enhance students’ knowledge of and perception about astronomy and science in general. The study design uses a pre-/post-test quasi-experimental study design measuring students’ normalized gain scores, calculated as per Hake (1998) and Prather (2009), using a slightly modified version of S. Slater’s (2011) Test Of Astronomy STandards TOAST combined with other instruments. The results of this initial study will guide the iterative development of ASTRO 101 ILDs that are intended to both be effective at enhancing student achievement and easy for instructors to successfully implement.
Payload specialist Ronald Parise checks on ASTRO-2 payload

NASA Technical Reports Server (NTRS)

1995-01-01

Payload specialist Ronald A. Parise, a senior scientist in the Space Observatories Department of Computer Sciences Corporation (CSC), checks on the ASTRO-2 payload (out of frame in the cargo bay of the Space Shuttle Endeavour). Parise is on the aft flight deck of the Earth orbiting Endeavour during STS-67.
Project ASTRO: How-To Manual for Teachers and Astronomers.

ERIC Educational Resources Information Center

Richter, Jessica; Fraknoi, Andrew

Project ASTRO is an innovative program to support science education by linking teachers and students in grades 4-9 with amateur and professional astronomers with the overall goal being to increase students' interest in astronomy and science in general. This manual was designed for teachers, amateur and professional astronomers, youth group…
The AstroPAL Starter Pack: How to Create a Grad Mentoring Program That Fosters Equity and Inclusion in Your Department

NASA Astrophysics Data System (ADS)

Cabrera, Nicole

2017-01-01

The Astronomy Peer Advising Leaders program (AstroPAL) at Georgia State University is a grassroots effort initiated by one PhD student with no budget, yet has quickly become a successful program that especially impacts students of marginalized identities. AstroPAL provides guidance for incoming grad students and helps them adjust to the workload, stress, and other difficulties that can come with grad school. This talk will cover the AstroPAL goals and accomplishments, its logistical structure, and its longterm sustainability. We will discuss how the program has helped create a bridge between faculty and students as well as the positive effect it has had on our community. I will also provide tools that anyone can use to launch AstroPAL at their home institution.
Astrobites: The Astro-ph Reader's Digest For Undergraduates

NASA Astrophysics Data System (ADS)

Newton, Elisabeth R.; Kohler, S.; Gifford, D.; Plunkett, A. L.; Astrobites Team

2012-01-01

Astrobites (http://astrobites.com) is a daily blog aimed primarily at undergraduates interested in astrophysical research and written by a team of graduate students from around the country. Every day we present a journal article recently posted to astro-ph in a brief format that is accessible to anyone with a general background in the physical sciences. In addition to summarizing new work, Astrobites provides valuable context for readers not yet familiar with the astrophysical literature. Special posts offer career guidance for undergraduates (e.g. applying for an NSF graduate fellowship) and describe personal experiences (e.g. attending an astronomy summer school). We will discuss the Astrobites format, readership statistics and the results of our October reader survey (117 responses). The Astrobites blog is currently receiving 17000 on-site hits per month with an average of 600 all-time views per post. 17% of our readers are undergraduate students and 34% are graduates, while researchers and astronomy enthusiasts make up the remainder in equal parts. Out of the 60 students surveyed, 75% plan on a career in research in astrophysics. EN and DG acknowledge support from the National Science Foundation through Graduate Research Fellowships.
Swift J1658.2-4242 as observed by AstroSat LAXPC

NASA Astrophysics Data System (ADS)

Beri, Aru; Belloni, Tomaso; Vincentelli, Federico; Gandhi, Poshak; Altamirano, Diego

2018-03-01

We report on preliminary analysis of an AstroSat observation of the newly discovered X-ray transient, Swift J1658.2-4242 [J1658] (GCN #22416, #22417, #22419; ATel #11306, #11307, #11310, #11311, #11318, #11321, #11336).
AstroCloud, a Cyber-Infrastructure for Astronomy Research: Data Archiving and Quality Control

NASA Astrophysics Data System (ADS)

He, B.; Cui, C.; Fan, D.; Li, C.; Xiao, J.; Yu, C.; Wang, C.; Cao, Z.; Chen, J.; Yi, W.; Li, S.; Mi, L.; Yang, S.

2015-09-01

AstroCloud is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences)1(Cui et al. 2014). To archive the astronomical data in China, we present the implementation of the astronomical data archiving system (ADAS). Data archiving and quality control are the infrastructure for the AstroCloud. Throughout the data of the entire life cycle, data archiving system standardized data, transferring data, logging observational data, archiving ambient data, And storing these data and metadata in database. Quality control covers the whole process and all aspects of data archiving.
Space Students Visit MSFC During STS-35 Astro-1 Mission

NASA Technical Reports Server (NTRS)

1990-01-01

The primary objective of the STS-35 mission was round the clock observation of the celestial sphere in ultraviolet and X-Ray astronomy with the Astro-1 observatory which consisted of four telescopes: the Hopkins Ultraviolet Telescope (HUT); the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE); the Ultraviolet Imaging Telescope (UIT); and the Broad Band X-Ray Telescope (BBXRT). The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Teams of controllers and researchers directed on-orbit science operations, sent commands to the spacecraft, received data from experiments aboard the Space Shuttle, adjusted mission schedules to take advantage of unexpected science opportunities or unexpected results, and worked with crew members to resolve problems with their experiments. This photo is of Space classroom students in the Discovery Optics Lab at MSFC during STS-35, ASTRO-1 mission payload operations.
The Sustainable Development of Space: Astro-environmental and dynamical considerations

NASA Astrophysics Data System (ADS)

Boley, Aaron; Byers, Michael; Russell, Sara

2018-04-01

The sustainable development of space is a global (and exo-global) challenge that is not limited by borders or research disciplines. Sustainable development is "development that meets the needs of the present without compromising the ability of future generations to meet their own needs". While the development of space brings new economic and scientific possibilities, it also carries significant political, legal, and technical uncertainties. For example, the rapidly increasing accessibility of space is motivating states to unilaterally adopt legislation for the new era of space use, which may have significant unintended consequences, such as increased risks to space assets, disputes among state as well as non-state actors, and changes to unique astro-environments. Any policy or legal position must be informed by the dynamical and astrophysical realities of space use, creating complex and interwoven challenges. Here, we explore several of these potential challenges related to astro-environmentalism, space minining operations, and the associated dynamics.
The Cadmium Zinc Telluride Imager on AstroSat

NASA Astrophysics Data System (ADS)

Bhalerao, V.; Bhattacharya, D.; Vibhute, A.; Pawar, P.; Rao, A. R.; Hingar, M. K.; Khanna, Rakesh; Kutty, A. P. K.; Malkar, J. P.; Patil, M. H.; Arora, Y. K.; Sinha, S.; Priya, P.; Samuel, Essy; Sreekumar, S.; Vinod, P.; Mithun, N. P. S.; Vadawale, S. V.; Vagshette, N.; Navalgund, K. H.; Sarma, K. S.; Pandiyan, R.; Seetha, S.; Subbarao, K.

2017-06-01

The Cadmium Zinc Telluride Imager (CZTI) is a high energy, wide-field imaging instrument on AstroSat. CZTI's namesake Cadmium Zinc Telluride detectors cover an energy range from 20 keV to >200 keV, with 11% energy resolution at 60 keV. The coded aperture mask attains an angular resolution of 17^' over a 4.6° × 4.6° (FWHM) field-of-view. CZTI functions as an open detector above 100 keV, continuously sensitive to GRBs and other transients in about 30% of the sky. The pixellated detectors are sensitive to polarization above ˜ 100 keV, with exciting possibilities for polarization studies of transients and bright persistent sources. In this paper, we provide details of the complete CZTI instrument, detectors, coded aperture mask, mechanical and electronic configuration, as well as data and products.
Project ASTRO NOVA brings Standard Based Astronomy to New Jersey Schools.

NASA Astrophysics Data System (ADS)

van der Veen, W.; Vinski, J.; Gallagher, A. C.

2000-12-01

Begun in 1998, Project ASTRO NOVA is hosted by the Planetarium at Raritan Valley Community College in Somerville, New Jersey. It is part of a National Network of eleven Project ASTRO sites created by the Astronomical Society of the Pacific with financial support of the National Science Foundation (see other papers at this meeting). Our goal is to bring hands-on inquiry based astronomy into classrooms and help teachers meet the New Jersey Science Standards. New Jersey mandates the teaching of astronomy in grades K-12 and statewide assessment takes place in grades 4 and 8. Capitalizing on New Jersey's record number of amateur astronomers per capita our site has trained 75 astronomers (including 21 professional astronomers) over the last three years. Before the start of each school year a new group of astronomers is trained together with their partner teacher(s) in the use of hands-on and age-appropriate astronomy activities that support the New Jersey Science Standards. Astronomers adopt a classroom and visit the same students at least four times during the year. Currently 53 astronomers are participating during the 2000-2001 school year. The program in New Jersey targets teachers in grades 3-9. A total of 114 teachers have been training at our annual workshops and 75 of them are participating during the 2000-2001 school year. Satisfaction with the program has been high with students, teachers and astronomers. When students meet scientists as role models and experience that doing science can be a lot of fun they become more interested. At the same time teachers are re-energized and gain a better understanding of how to teach science and astronomy. Finally, astronomers have the satisfaction of making a real difference in the lives of thousands of children, gain a better understanding of the issues in K-12 education and learn new teaching strategies for use in their college classes or astronomy clubs. In general we find that students and teachers are becoming better
Matroshka AstroRad Radiation Experiment (MARE) on the Deep Space Gateway

NASA Astrophysics Data System (ADS)

Gaza, R.; Hussein, H.; Murrow, D.; Hopkins, J.; Waterman, G.; Milstein, O.; Berger, T.; Przybyla, B.; Aeckerlein, J.; Marsalek, K.; Matthiae, D.; Rutczynska, A.

2018-02-01

The Matroshka AstroRad Radiation Experiment is a science payload on Orion EM-1 flight. A research platform derived from MARE is proposed for the Deep Space Gateway. Feedback is invited on desired Deep Space Gateway design features to maximize its science potential.
Do You Always Need a Textbook to Teach Astro 101?

ERIC Educational Resources Information Center

Rudolph, Alexander L.

2013-01-01

The increasing use of interactive learning [IL] strategies in Astro 101 classrooms has led some instructors to consider the usefulness of a textbook in such classes. These strategies provide students a learning modality very different from the traditional lecture supplemented by reading a textbook and homework and raise the question of whether the…
AstroBioLab: A Mobile Biotic and Soil Analysis Laboratory

NASA Technical Reports Server (NTRS)

Bada, J. L.; Zent, A. P.; Grunthaner, F. J.; Quinn, R. C.; Navarro-Gonzalex, R.; Gonez-Silva, B.; McKay, C. P.

2003-01-01

The Jet Propulsion Laboratory, Scripps Institution of Oceanography, and NASA Ames Research Center are currently developing a mobile Astrobiology Laboratory (AstroBioLab) for a series of field campaigns using the Chilean Atacama Desert as a Martian surface analog site. The Astrobiology Science and Technology for Exploring Planets (ASTEP) program funded AstroBioLab is designed around the Mars Organic Detector (MOD) instrument and the Mars Oxidant Instrument (MOI) which provide complementary data sets. Using this suite of Mars Instrument Development Program (MIDP) and Planetary Instrument Definition and Development Program (PIDDP) derived in situ instruments, which provide state-of-the-art organic compound detection (attomolar sensitivity) and depth profiling of oxidation chemistry, we measure and correlate the interplay of organic compounds, inorganic oxidants, UV irradiation and water abundance. This mobile laboratory studies the proposition that intense UV irradiation coupled with low levels of liquid water generates metastable oxidizing species that can consume moderate amounts of seeded organic compounds. Results from the initial spring 2003 field campaign will be presented.
Scanning sky monitor (SSM) onboard AstroSat

NASA Astrophysics Data System (ADS)

Ramadevi, M. C.; Seetha, S.; Bhattacharya, Dipankar; Ravishankar, B. T.; Sitaramamurthy, N.; Meena, G.; Sharma, M. Ramakrishna; Kulkarni, Ravi; Babu, V. Chandra; Kumar; Singh, Brajpal; Jain, Anand; Yadav, Reena; Vaishali, S.; Ashoka, B. N.; Agarwal, Anil; Balaji, K.; Nagesh, G.; Kumar, Manoj; Gaan, Dhruti Ranjan; Kulshresta, Prashanth; Agarwal, Pankaj; Sebastian, Mathew; Rajarajan, A.; Radhika, D.; Nandi, Anuj; Girish, V.; Agarwal, Vivek Kumar; Kushwaha, Ankur; Iyer, Nirmal Kumar

2017-10-01

Scanning Sky Monitor (SSM) onboard AstroSat is an Xray sky monitor in the soft X-ray band designed with a large field of view to detect and locate transient X-ray sources and alert the astronomical community about interesting phenomena in the X-ray sky. SSM comprises position sensitive proportional counters with 1D coded mask for imaging. There are three detector units mounted on a platform capable of rotation which helps covering about 50% of the sky in one full rotation. This paper discusses the elaborate details of the instrument and few immediate results from the instrument after launch.

Astro-H Data Analysis, Processing and Archive

NASA Technical Reports Server (NTRS)

Angelini, Lorella; Terada, Yukikatsu; Loewenstein, Michael; Miller, Eric D.; Yamaguchi, Hiroya; Yaqoob, Tahir; Krimm, Hans; Harrus, Ilana; Takahashi, Hiromitsu; Nobukawa, Masayoshi;

2016-01-01

Astro-H (Hitomi) is an X-ray Gamma-ray mission led by Japan with international participation, launched on February 17, 2016. The payload consists of four different instruments (SXS, SXI, HXI and SGD) that operate simultaneously to cover the energy range from 0.3 keV up to 600 keV. This paper presents the analysis software and the data processing pipeline created to calibrate and analyze the Hitomi science data along with the plan for the archive and user support.These activities have been a collaborative effort shared between scientists and software engineers working in several institutes in Japan and USA.

Wide-field direct CCD observations supporting the Astro-1 Space Shuttle mission's Ultraviolet Imaging Telescope

NASA Technical Reports Server (NTRS)

Hintzen, Paul; Angione, Ron; Talbert, Freddie; Cheng, K.-P.; Smith, Eric; Stecher, Theodore P.

1993-01-01

Wide field direct CCD observations are being obtained to support and complement the vacuum-ultraviolet (VUV) images provided by Astro's Ultraviolet Imaging Telescope (UIT) during a Space Shuttle flight in December 1990. Because of the wide variety of projects addressed by UIT, the fields observed include (1) galactic supernova remnants such as the Cygnus Loop and globular clusters such as Omega Cen and M79; (2) the Magellanic Clouds, M33, M81, and other galaxies in the Local Group; and (3) rich clusters of galaxies, principally the Perseus cluster and Abell 1367. Ground-based observations have been obtained for virtually all of the Astro-1 UIT fields. The optical images allow identification of individual UV sources in each field and provide the long baseline in wavelength necessary for accurate analysis of UV-bright sources. To facilitate use of our optical images for analysis of UIT data and other projects, we plan to archive them, with the UIT images, at the National Space Science Data Center (NSSDC), where they will be universally accessible via anonymous FTP. The UIT, one of three telescopes comprising the Astro spacecraft, is a 38-cm f/9 Ritchey-Chretien telescope on which high quantum efficiency, solar-blind image tubes are used to record VUV images on photographic film. Five filters with passbands centered between 1250A and 2500A provide both VUV colors and a measurement of extinction via the 2200A dust feature. The resulting calibrated VUV pictures are 40 arcminutes in diameter at 2.5 arcseconds resolution. The capabilities of UIT, therefore, complement HST's WFPC: the latter has 40 times greater collecting area, while UIT's usable field has 170 times WFPC's field area.
The ASTRO-H SXT Performance to the Large Off-Set Angles

NASA Technical Reports Server (NTRS)

Sato, Toshiki; Iizuka, Ryo; Mori, Hideyuki; Hayashi, Takayuki; Maeda, Yoshitomo; Ishida, Manabu; Kikuchi, Naomichi; Kurashima, Sho; Nakaniwa, Nozomi; Okajima, Takashi;

2016-01-01

The X-ray astronomy satellite ASTRO-H, which is the 6th Japanese X-ray astronomy satellite and is renamed Hitomi after launch, is designed to observe celestial X-ray objects in a wide energy band from a few hundred eV to 600 keV. The Soft X-ray Telescopes (SXTs) onboard ASTRO-H play a role of collecting and imaging X-rays up to approximately 12 keV. Although the field of view of the SXT is approximately 15' (FWHM), due to the thin-foil-nested Wolter-I type optics adopted in the SXTs, X-rays out of the field of view can reach the focal plane without experiencing a normal double reflection. This component is referred to as 'stray light'. Owing to investigation of the stray light so far, 'secondary reflection' is now identified as the main component of the stray light, which is composed of X-rays reflected only by secondary reflectors. In order to cut the secondary reflections, a 'pre-collimator' is equipped on top of the SXTs. However, we cannot cut all the stray lights with the pre-collimator in some off-axis angle domain. In this study, we measure the brightness of the stray light of the SXTs at some representative off-axis angles by using the ISAS X-ray beam line. ASTRO-H is equipped with two modules of the SXT; one is for the Soft X-ray Spectrometer (SXS), an X-ray calorimeter, and the other is for the Soft X-ray Imager (SXI), an X-ray CCD camera. These SXT modules are called SXT-S and SXT-I, respectively. Of the two detector systems, the SXI has a large field of view, a square with 38' on a side. To cope with this, we have made a mosaic mapping of the stray light at a representative off-axis angle of 30' in the X-ray beam line at the Institute of Space and Astronautical Science. The effective area of the brightest secondary reflection is found of order approximately 0.1% of the on-axis effective area at the energy of 1.49 keV. The other components are not so bright (less than 5 x 10(exp -4) times smaller than the on-axis effective area). On the other hand, we

Validation of a digital mammographic unit model for an objective and highly automated clinical image quality assessment.

PubMed

Perez-Ponce, Hector; Daul, Christian; Wolf, Didier; Noel, Alain

2013-08-01

In mammography, image quality assessment has to be directly related to breast cancer indicator (e.g. microcalcifications) detectability. Recently, we proposed an X-ray source/digital detector (XRS/DD) model leading to such an assessment. This model simulates very realistic contrast-detail phantom (CDMAM) images leading to gold disc (representing microcalcifications) detectability thresholds that are very close to those of real images taken under the simulated acquisition conditions. The detection step was performed with a mathematical observer. The aim of this contribution is to include human observers into the disc detection process in real and virtual images to validate the simulation framework based on the XRS/DD model. Mathematical criteria (contrast-detail curves, image quality factor, etc.) are used to assess and to compare, from the statistical point of view, the cancer indicator detectability in real and virtual images. The quantitative results given in this paper show that the images simulated by the XRS/DD model are useful for image quality assessment in the case of all studied exposure conditions using either human or automated scoring. Also, this paper confirms that with the XRS/DD model the image quality assessment can be automated and the whole time of the procedure can be drastically reduced. Compared to standard quality assessment methods, the number of images to be acquired is divided by a factor of eight. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.
AstroCom NYC: A City Partnership for the Next Generation of Astrophysicists

NASA Astrophysics Data System (ADS)

Paglione, Timothy; Ford, K. E. Saavik; Robbins, Dennis; Mac Low, Mordecai; Agüeros, Marcel; Anchordoqui, Luis; Acquaviva, Viviana; Bellovary, Jillian; Cruz, Kelle; Liu, Charles; Maller, Ari; McKernan, Barry; Minor, Quinn; O'Dowd, Matthew; Rice, Emily; Sheffield, Allyson

2018-01-01

AstroCom NYC is an undergraduate mentoring program designed to improve urban minority student access to opportunities in astrophysical research by greatly enhancing partnerships between research astronomers in New York City (City University of New York – an MSI, American Museum of Natural History, and Columbia). AstroCom NYC also partnered this past year with the Flatiron Institute Center for Computational Astrophysics to provide new and exciting midtown opportunities for students, and foster an expanding mentor network through the city. We provide centralized, personalized mentoring as well as financial and academic support, to CUNY undergraduates throughout their studies, plus the resources and opportunities to further CUNY faculty research with students. The goal is that students’ residency in the unique research environments at AMNH and the CCA helps them build a sense of belonging in the field, and readies and inspires them for graduate study. We welcomed our fifth and largest cohort last year, and had some of our first graduates accepted to grad school and bridge programs.
Soft X-ray Focusing Telescope Aboard AstroSat: Design, Characteristics and Performance

NASA Astrophysics Data System (ADS)

Singh, K. P.; Stewart, G. C.; Westergaard, N. J.; Bhattacharayya, S.; Chandra, S.; Chitnis, V. R.; Dewangan, G. C.; Kothare, A. T.; Mirza, I. M.; Mukerjee, K.; Navalkar, V.; Shah, H.; Abbey, A. F.; Beardmore, A. P.; Kotak, S.; Kamble, N.; Vishwakarama, S.; Pathare, D. P.; Risbud, V. M.; Koyande, J. P.; Stevenson, T.; Bicknell, C.; Crawford, T.; Hansford, G.; Peters, G.; Sykes, J.; Agarwal, P.; Sebastian, M.; Rajarajan, A.; Nagesh, G.; Narendra, S.; Ramesh, M.; Rai, R.; Navalgund, K. H.; Sarma, K. S.; Pandiyan, R.; Subbarao, K.; Gupta, T.; Thakkar, N.; Singh, A. K.; Bajpai, A.

2017-06-01

The Soft X-ray focusing Telescope (SXT), India's first X-ray telescope based on the principle of grazing incidence, was launched aboard the AstroSat and made operational on October 26, 2015. X-rays in the energy band of 0.3-8.0 keV are focussed on to a cooled charge coupled device thus providing medium resolution X-ray spectroscopy of cosmic X-ray sources of various types. It is the most sensitive X-ray instrument aboard the AstroSat. In its first year of operation, SXT has been used to observe objects ranging from active stars, compact binaries, supernova remnants, active galactic nuclei and clusters of galaxies in order to study its performance and quantify its characteriztics. Here, we present an overview of its design, mechanical hardware, electronics, data modes, observational constraints, pipeline processing and its in-orbit performance based on preliminary results from its characterization during the performance verification phase.
The EBIT Calorimeter Spectrometer: a new, permanent user facility at the LLNL EBIT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Porter, F S; Beiersdorfer, P; Brown, G V

The EBIT Calorimeter Spectrometer (ECS) is currently being completed and will be installed at the EBIT facility at the Lawrence Livermore National Laboratory in October 2007. The ECS will replace the smaller XRS/EBIT microcalorimeter spectrometer that has been in almost continuous operation since 2000. The XRS/EBIT was based on a spare laboratory cryostat and an engineering model detector system from the Suzaku/XRS observatory program. The new ECS spectrometer was built to be a low maintenance, high performance implanted silicon microcalorimeter spectrometer with 4 eV resolution at 6 keV, 32 detector channels, 10 {micro}s event timing, and capable of uninterrupted acquisitionmore » sessions of over 60 hours at 50 mK. The XRS/EBIT program has been very successful, producing many results on topics such as laboratory astrophysics, atomic physics, nuclear physics, and calibration of the spectrometers for the National Ignition Facility. The ECS spectrometer will continue this work into the future with improved spectral resolution, integration times, and ease-of-use. We designed the ECS instrument with TES detectors in mind by using the same highly successful magnetic shielding as our laboratory TES cryostats. This design will lead to a future TES instrument at the LLNL EBIT. Here we discuss the legacy of the XRS/EBIT program, the performance of the new ECS spectrometer, and plans for a future TES instrument.« less
AstroDAbis: Annotations and Cross-Matches for Remote Catalogues

NASA Astrophysics Data System (ADS)

Gray, N.; Mann, R. G.; Morris, D.; Holliman, M.; Noddle, K.

2012-09-01

Astronomers are good at sharing data, but poorer at sharing knowledge. Almost all astronomical data ends up in open archives, and access to these is being simplified by the development of the global Virtual Observatory (VO). This is a great advance, but the fundamental problem remains that these archives contain only basic observational data, whereas all the astrophysical interpretation of that data — which source is a quasar, which a low-mass star, and which an image artefact — is contained in journal papers, with very little linkage back from the literature to the original data archives. It is therefore currently impossible for an astronomer to pose a query like “give me all sources in this data archive that have been identified as quasars” and this limits the effective exploitation of these archives, as the user of an archive has no direct means of taking advantage of the knowledge derived by its previous users. The AstroDAbis service aims to address this, in a prototype service enabling astronomers to record annotations and cross-identifications in the AstroDAbis service, annotating objects in other catalogues. We have deployed two interfaces to the annotations, namely one astronomy-specific one using the TAP protocol (Dowler et al. 2011), and a second exploiting generic Linked Open Data (LOD) and RDF techniques.
Expected radiation damage of reverse-type APDs for the Astro-H mission

NASA Astrophysics Data System (ADS)

Kataoka, J.; Saito, T.; Yoshino, M.; Mizoma, H.; Nakamori, T.; Yatsu, Y.; Ishikawa, Y.; Matsunaga, Y.; Tajima, H.; Kokubun, M.; Edwards, P. G.

2012-06-01

Scheduled for launch in 2014, Astro-H is the sixth Japanese X-ray astronomy satellite mission. More than 60 silicon avalanche photodiodes (Si-APDs; hereafter APDs) will be used to read out BGO scintillators, which are implemented to generate a veto signal to reduce background contamination for the hard X-ray imager (HXI) and a soft gamma-ray detector (SGD). To date, however, APDs have rarely been used in space experiments. Moreover, strict environmental tests are necessary to guarantee APD performance for missions expected to extend beyond five years. The radiation hardness of APDs, as for most semiconductors, is particularly crucial, since radiation in the space environment is severe. In this paper, we present the results of radiation tests conducted on reverse-type APDs (provided by Hamamatsu Photonics) irradiated by gamma rays (60Co) and 150 MeV protons. We show that, even under the same 100 Gy dose, high energy protons can cause displacement (bulk) damage in the depletion region and possibly change the activation energy, whereas gamma-ray irradiation is less prone to cause damage, because ionization damage dominates only the surface region. We also present quantitative guidance on how to estimate APD noise deterioration over a range of temperatures and radiation doses. As a practical example, we discuss the expected degradation of the BGO energy threshold for the generation of veto signals, following several years of Astro-H operation in Low Earth Orbit (LEO), and directly compare it to experimental results obtained using a small BGO crystal.
AstroCom NYC: A Partnership Between Astronomers at CUNY, AMNH, and Columbia University

NASA Astrophysics Data System (ADS)

Paglione, Timothy; Ford, K. S.; Robbins, D.; Mac Low, M.; Agueros, M. A.

2014-01-01

AstroCom NYC is a new program designed to improve urban minority student access to opportunities in astrophysical research by greatly enhancing partnerships between research astronomers in New York City. The partners are minority serving institutions of the City University of New York, and the astrophysics research departments of the American Museum of Natural History and Columbia. AstroCom NYC provides centralized, personalized mentoring as well as financial and academic support, to CUNY undergraduates throughout their studies, plus the resources and opportunities to further CUNY faculty research with students. The goal is that students’ residency at AMNH helps them build a sense of belonging in the field, and inspires and prepares them for graduate study. AstroCom NYC prepares students for research with a rigorous Methods of Scientific Research course developed specifically to this purpose, a laptop, a research mentor, career mentor, involvement in Columbia outreach activities, scholarships and stipends, Metrocards, and regular assessment for maximum effectiveness. Stipends in part alleviate the burdens at home typical for CUNY students so they may concentrate on their academic success. AMNH serves as the central hub for our faculty and students, who are otherwise dispersed among all five boroughs of the City. With our first cohort we experienced the expected challenges from their diverse preparedness, but also far greater than anticipated challenges in scheduling, academic advisement, and molding their expectations. We review Year 1 operations and outcomes, as well as plans for Year 2, when our current students progress to be peer mentors.
Developing Resource Guides for Astro 101 Instructors, as a Higher Education Community Collaboration from the NASA Astrophysics SEPOF

NASA Astrophysics Data System (ADS)

Schultz, Gregory R.; Fraknoi, A.; Smith, D.; Manning, J.

2012-01-01

The NASA/SMD-funded Astrophysics SEPOF (Science Education & Public Outreach Forum) has been organizing EPO "community collaborations” as part of its coordination efforts with missions and EPO programs within NASA Astrophysics. One of the community collaborations that emerged has been focusing on higher education, with a particular emphasis on introductory astronomy courses ("Astro 101"), and how NASA EPO programs and materials can help serve the needs of these courses’ instructors. One of the consequent efforts that has begun is the compiling and development of topical Resource Guides for Astro 101 instructors, with the initial subject tackled being cosmology. This is an area in basic astronomy where rapid progress is being made, older textbooks are quickly out of date, and ideas are challenging for many students, and even instructors! We have had informal conversations so far with about a dozen instructors, divided among universities, liberal-arts colleges, and 2-year community colleges. We have also gathered feedback regarding suggested cosmology resources from the EPO community served by the NASA Astrophysics Forum. And we have undertaken an independent search for Astro 101-suitable curriculum materials, from NASA and other sources, and identified a useful set of such materials, in print and on the Web. Results from this investigation will be shared, along with our project's initial Cosmology Resource Guide, and plans for follow-up guides. Feedback is solicited from Astro 101 instructors, resource developers, and EPO professionals.
In-Orbit Operation of the ASTRO-H SXS

NASA Technical Reports Server (NTRS)

Tsujimoto, Masahiro; Mitsuda, Kazuhisa; Kelley, Richard L.; den Herder, Jan-Willem A.; Akamatsu, Hiroki; Bialas, Thomas G.; Boyce, Kevin R.; Brown, Gregory V.; Chiao, Meng P.; Costantini, Elisa;

2016-01-01

We summarize all the in-orbit operations of the Soft X-ray Spectrometer (SXS) onboard the ASTRO-H (Hitomi) satellite. The satellite was launched on 2016-02- 17 and the communication with the satellite ceased on2016-03-26. The SXS was still in the commissioning phase, in which the setups were progressively changed. This article is intended to serve as a reference of the events in the orbit to properly interpret the SXS data taken during its short life time, and as a test case for planning the in-orbit operation for future micro-calorimeter missions.

In-orbit operation of the ASTRO-H SXS

NASA Astrophysics Data System (ADS)

Tsujimoto, Masahiro; Mitsuda, Kazuhisa; Kelley, Richard L.; den Herder, Jan-Willem A.; Akamatsu, Hiroki; Bialas, Thomas G.; Boyce, Kevin R.; Brown, Gregory V.; Chiao, Meng P.; Costantini, Elisa; de Vries, Cor P.; DiPirro, Michael J.; Eckart, Megan E.; Ezoe, Yuichiro; Fujimoto, Ryuichi; Haas, Daniel; Hoshino, Akio; Ishikawa, Kumi; Ishisaki, Yoshitaka; Iyomoto, Naoko; Kilbourne, Caroline A.; Kitamoto, Shunji; Koyama, Shu; Leutenegger, Maurice A.; McCammon, Dan; Mitsuishi, Ikuyuki; Murakami, Hiroshi; Murakami, Masahide; Noda, Hirofumi; Ogawa, Mina; Ota, Naomi; Paltani, Stéphane; Porter, Frederick S.; Sato, Kosuke; Sato, Yoichi; Sawada, Makoto; Seta, Hiromi; Shinozaki, Keisuke; Shirron, Peter J.; Sneiderman, Gary A.; Sugita, Hiroyuki; Szymkowiak, Andrew E.; Takei, Yoh; Tamagawa, Toru; Tashiro, Makoto S.; Terada, Yukikatsu; Yamada, Shinya; Yamasaki, Noriko Y.; Yatsu, Yoichi

2016-07-01

We summarize all the in-orbit operations of the Soft X-ray Spectrometer (SXS) onboard the ASTRO-H (Hit- omi) satellite. The satellite was launched on 2016/02/17 and the communication with the satellite ceased on 2016/03/26. The SXS was still in the commissioning phase, in which the setups were progressively changed. This article is intended to serve as a reference of the events in the orbit to properly interpret the SXS data taken during its short life time, and as a test case for planning the in-orbit operation for future micro-calorimeter missions.
Early In-orbit Performance of Scanning Sky Monitor Onboard AstroSat

NASA Astrophysics Data System (ADS)

Ramadevi, M. C.; Ravishankar, B. T.; Sitaramamurthy, N.; Meena, G.; Singh, Brajpal; Jain, Anand; Yadav, Reena; Agarwal, Anil; Babu, V. Chandra; Kumar; Kushwaha, Ankur; Vaishali, S.; Iyer, Nirmal Kumar; Nandi, Anuj; Girish, V.; Agarwal, Vivek Kumar; Seetha, S.; Bhattacharya, Dipankar; Balaji, K.; Kumar, Manoj; Kulshresta, Prashanth

2017-06-01

We report the in-orbit performance of Scanning Sky Monitor (SSM) onboard AstroSat. The SSM operates in the energy range 2.5 to 10 keV and scans the sky to detect and locate transient X-ray sources. This information of any interesting phenomenon in the X-ray sky as observed by SSM is provided to the astronomical community for follow-up observations. Following the launch of AstroSat on 28th September, 2015, SSM was commissioned on October 12th, 2015. The first power ON of the instrument was with the standard X-ray source, Crab in the field-of-view. The first orbit data revealed the basic expected performance of one of the detectors of SSM, SSM1. Following this in the subsequent orbits, the other detectors were also powered ON to find them perform in good health. Quick checks of the data from the first few orbits revealed that the instrument performed with the expected angular resolution of 12' × 2.5° and effective area in the energy range of interest. This paper discusses the instrument aspects along with few on-board results immediately after power ON.
The EBIT Calorimeter Spectrometer: A New, Permanent User Facility at the LLNL EBIT

NASA Technical Reports Server (NTRS)

Porter, S.

2007-01-01

The EBIT Calorimeter Spectrometer (ECS) has recently been completed and is currently being installed at the EBIT facility at the Lawrence Livermore National Laboratory. The ECS will replace the smaller XRS/EBIT spectrometer that has been in almost continuous operation since 2000. The XRS/EBIT was based on a spare laboratory cryostat and an engineering model detector system from the Suzaku/XRS observatory. The new ECS spectrometer was built from the ground up to be a low maintenance, high performance microcalorimeter spectrometer with 4 eV resolution at 6 keV, 32 detector channels, 10 us event timing, and capable of uninterrupted acquisition sessions of over 70 hours at 50 mK. The XRSIEBIT program has been extremely successful, producing over two-dozen refereed publications on topics such as laboratory astrophysics, atomic physics, nuclear physics, and calibration of the spectrometers for the National Ignition Facility, with many more publications in preparation. The ECS spectrometer will continue this work into the future with improved spectral resolution, integration times, and ease-of-use. We designed the ECS instrument with TES detectors in mind by using the same highly successful magnetic shielding as our laboratory TES cryostats. This design will lead to a future TES instrument at the LLNL EBIT. This proposed future instrument would include a hybrid detector system with 0.8 eV resolution in the band from 0.1-1.0 keV, 2 eV from 0.1-10 keV, and 30 eV from 0.5-100 keV, with high quantum efficiency in each band. Here we discuss the legacy of the XRS/EBIT program, the performance of the new ECS spectrometer, and plans for a future TES spectrometer.
Active Galactic Nuclei

NASA Technical Reports Server (NTRS)

Mushotzky, Richard

2004-01-01

In the last 5 years the first high quality moderate resolution spectra of AGN in the x-ray band have become available thanks to the gratings on Chandra and XMM. Next year this type of data will be extended to E > 3 keV with the launch of Astro-E2. I will summarize some of the outstanding results from these new data and what we may expect from Astro-E2.
Results from the Ultraviolet Imaging Telescope on the Astro-2 Mission

NASA Astrophysics Data System (ADS)

Stecher, T. P.; Bohlin, R. C.; Neff, S. G.; O'Connell, R. W.; Roberts, M. R.; Smith, A. M.

1995-03-01

The solar-blind UIT camera with a CsI cathode obtained 722 frames with a cumulative exposure time of 260705 seconds during the March 1995 Astro-2 mission of Space Shuttle Endeavour. Filters were used to isolate selected bandpasses in the range 1200-1800 Angstroms, over the 40 arcmin field of view. Spatial resolution on most of the images is about 3 arcsec. Calibrated data, converted to machine-readable form, are under analysis and several posters on these investigations are presented in the Astro-2 poster session at this meeting (a first look at the UIT observations of Omega Cen, M31, and the Cygnus Loop is further elaborated here). UIT imagery of 20 spiral galaxies was obtained as part of a Guest Investigator program (Wendy Freedman et al.). UV imaging suppresses the red stellar population as expected and enhances the appearance of tracers of recent star formation. Known \\hii regions in these galaxies are made apparent through the scattering of stellar ultraviolet light by interstellar dust; typically their shapes differ from those seen in \\ha. A radial color gradient investigation will be delayed until ground observations can be made as the long-wavelength camera failed on launch and only the 1520 Angstroms and 1620 Angstroms images were made. The far-UV (1520 Angstroms) features are detected well beyond the Holmberg radius. UV/visible color-magnitude diagrams will be made as they were for the data from Astro-1. Our deepest images of the Magellanic Clouds reveal a rich field of luminous clusters and stars that are being searched for UV counterparts of the known x-ray sources in the photographed areas. The observed stars in the Clouds will be used to determine the current mass function. The respective contributions of nebular and stellar UV light in reflection nebulae are will be studied as several nebulae were observed with differing geometries and will provide interesting results on the far-UV albedo and phase function of nebular dust. A dozen globular and
In-orbit performance of a helium dewar for the soft X-ray spectrometer onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Yoshida, Seiji; Miyaoka, Mikio; Kanao, Ken'ichi; Tsunematsu, Shoji; Otsuka, Kiyomi; Hoshika, Shunji; Narasaki, Katsuhiro; Mitsuda, Kazuhisa; Yamasaki, Noriko; Takei, Yoh; Fujimoto, Ryuichi; Ezoe, Yuichiro; Sato, Yoichi; Okamoto, Atsushi; Noda, Hirofumi; DiPirro, Michael; Shirron, Peter

2018-04-01

ASTRO-H was an X-ray astronomy satellite that the Japan Aerospace Exploration Agency (JAXA) developed to study the evolution of the universe and physical phenomena yet to be discovered. The primary scientific instrument of ASTRO-H was the Soft X-ray Spectrometer (SXS). Its detectors were to be cooled to 50 m K using a complex cryogenic system with a multistage adiabatic demagnetization refrigerator (ADR) developed by the National Aeronautics and Space Administration (NASA), and a cryogenic system developed by Sumitomo Heavy Industries, Ltd. (SHI). SHI's cryogenic system was required to cool the ADR's heatsink to 1.3 K or less in orbit for three years or longer. To meet these requirements, SHI developed a hybrid cryogenic system consisting of a liquid helium tank, a 4 K Joule-Thomson cooler, and two two-stage Stirling coolers. ASTRO-H was launched from Tanegashima Space Center on February 17, 2016. The initial operation of the SXS cryogenic system in orbit was completed successfully. The cooling performance was as expected and could have exceeded the lifetime requirement of three years. This paper describes results of ground tests, results of top-off filling of superfluid liquid helium just before launch, and cooling performance in orbit.
ASTRO 101 Labs and the Invasion of the Cognitive Scientists

NASA Astrophysics Data System (ADS)

Slater, Stephanie J.

2015-04-01

Since the mid 1800's there has been widespread agreement that we should be about the business of engaging students in the practices of scientific research in order to best teach the methods and practices of science. There has been significantly less agreement on precisely how to teach science by mimicking scientific inquiry in a way that can be empirically supported, even with our ``top students.'' Engaging ``ASTRO 101 students'' in scientific inquiry is a task that has left our astronomy education research community more than a little stymied, to the extent that it is difficult to find non-major science students practicing anything other than confirmation exercises in college labs. Researchers at the CAPER Center for Astronomy & Physics Education Research have struggled with this problem as well, until in our frustration we had to ask: ``Can research tell us anything about how to get students to do research?'' This talk presents an overview of the cognitive science that we've brought to bear in the ASTRO 101 laboratory setting for non-science majoring undergraduates and future teachers, along with the results of early studies that suggest that a ``backwards faded scaffolding'' approach to instruction in Intro Labs can successfully support large numbers of students in enhancing their understanding of the nature of scientific inquiry. Supported by NSF DUE 1312562.
Astro Academy: Principia--A Suite of Physical Science Demonstrations Conducted Aboard the ISS

ERIC Educational Resources Information Center

McMurray, Andy

2016-01-01

Astro Academy: Principia is an education programme developed by the UK National Space Academy for the UK Space Agency (UKSA) and the European Space Agency (ESA). The Academy designed, constructed, flight-qualified and developed experimental procedures for a suite of physics and chemistry demonstration experiments that were conducted by ESA…

Automated Structural Optimization System (ASTROS). Volume 2. User’s Manual

DTIC Science & Technology

1988-04-07

preparation and on the use of advanced features that permit the user to modify the standard execution of ASTROS. f^Q^S*. ) I I J...software in considera- ble detail to direct the procedure to perform these alternative functions. The mechanisms by which these more advanced features are...grossly modify the existing capabilities of the system. These more advanced topics are treated in the Programmer’s and Application Manuals which
MO-E-BRF-01: Research Opportunities in Technology for Innovation in Radiation Oncology (Highlight of ASTRO NCI 2013 Workshop)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hahn, S; Jaffray, D; Chetty, I

Radiotherapy is one of the most effective treatments for solid tumors, in large part due to significant technological advances associated with, for instance, the ability to target tumors to very high levels of accuracy (within millimeters). Technological advances have played a central role in the success of radiation therapy as an oncologic treatment option for patients. ASTRO, AAPM and NCI sponsored a workshop “Technology for Innovation in Radiation Oncology” at the NCI campus in Bethesda, MD on June 13–14, 2013. The purpose of this workshop was to bring together expert clinicians and scientists to discuss the role of disruptive technologiesmore » in radiation oncology, in particular with regard to how they are being developed and translated to clinical practice in the face of current and future challenges and opportunities. The technologies discussed encompassed imaging and delivery aspects, along with methods to enable/facilitate application of them in the clinic. Measures for assessment of the performance of these technologies, such as techniques to validate quantitative imaging, were reviewed. Novel delivery technologies, incorporating efficient and safe delivery mechanisms enabled by development of tools for process automation and the associated field of oncology informatics formed one of the central themes of the workshop. The discussion on disruptive technologies was grounded in the need for evidence of efficacy. Scientists in the areas of technology assessment and bioinformatics provided expert views on different approaches toward evaluation of technology efficacy. Clinicians well versed in clinical trials incorporating disruptive technologies (e.g. SBRT for early stage lung cancer) discussed the important role of these technologies in significantly improving local tumor control and survival for these cohorts of patients. Recommendations summary focused on the opportunities associated with translating the technologies into the clinic and assessing
ASTRO 850: Teaching Teachers about Exoplanets

NASA Astrophysics Data System (ADS)

Barringer, Daniel; Palma, Christopher

2017-01-01

The Earth and Space Science Partnership (ESSP) is a collaboration among Penn State scientists, science educators and seven school districts across Pennsylvania. Penn State also offers through its fully online World Campus the opportunity for In-Service science teachers to earn an M.Ed. degree in Earth Science, and we currently offer a required online astronomy course for that program. We have previously presented descriptions of how have incorporated research-based pedagogical practices into ESSP-sponsored workshops for in-service teachers (Palma et al. 2013), a pilot section of introductory astronomy for non-science majors (Palma et al. 2014), and into the design of an online elective course on exoplanets for the M.Ed. in Earth Science (Barringer and Palma, 2016). Here, we present the finished version of that exoplanet course, ASTRO 850. We gratefully acknowledge support from the NSF MSP program award DUE#0962792.
Re-excision rates after breast conserving surgery following the 2014 SSO-ASTRO guidelines.

PubMed

Heelan Gladden, Alicia A; Sams, Sharon; Gleisner, Ana; Finlayson, Christina; Kounalakis, Nicole; Hosokawa, Patrick; Brown, Regina; Chong, Tae; Mathes, David; Murphy, Colleen

2017-12-01

In 2014, SSO-ASTRO published guidelines which recommended "no ink on tumor" as adequate margins for patients undergoing breast conservation for invasive breast cancer. In 2016, new SSO-ASTRO-ASCO guidelines recommended 2 mm margins for DCIS. We evaluated whether these guidelines affected re-excision rates at our institution. Patients treated with breast conservation surgery from January 1, 2010-March 1, 2016 were identified. Re-excision rates, tumor characteristics, and presence of residual disease were recorded. The 2016 guidelines were retrospectively applied to the same cohort and expected re-excision rates calculated. Re-excision rates did not significantly decline before and after 2014 guideline adoption (11.9% before, 10.9% after; p = 0.65) or when the 2016 guidelines were retrospectively applied (8.4%; p = 0.10). The 2014 and 2016 guidelines had minimal impact on our re-excision rates, as most re-excisions were done for DCIS and 2016 guidelines supported our prior institutional practices of 2 mm margins for these patients. Copyright © 2017 Elsevier Inc. All rights reserved.
AstroSat /LAXPC Observation of Cygnus X-1 in the Hard State

DOE Office of Scientific and Technical Information (OSTI.GOV)

Misra, Ranjeev; Pahari, Mayukh; Yadav, J S

2017-02-01

We report the first analysis of data from AstroSat /LAXPC observations of Cygnus X-1 in 2016 January. LAXPC spectra reveals that the source was in the canonical hard state, represented by a prominent thermal Comptonization component having a photon index of ∼1.8 and high temperature of kT{sub e} > 60 keV along with weak reflection and possible disk emission. The power spectrum can be characterized by two broad lorentzian functions centered at ∼0.4 and ∼3 Hz. The rms of the low-frequency component decreases from ∼15% at around 4 keV to ∼10% at around 50 keV, while that of the high-frequencymore » one varies less rapidly from ∼13.5% to ∼11.5% in the same energy range. The time lag between the hard (20–40 keV) and soft (5–10 keV) bands varies in a step-like manner being nearly constant at ∼50 milliseconds from 0.3 to 0.9 Hz, decreasing to ∼8 milliseconds from 2 to 5 Hz and finally dropping to ∼2 milliseconds for higher frequencies. The time lags increase with energy for both the low and high-frequency components. The event mode LAXPC data allows for flux resolved spectral analysis on a timescale of 1 s, which clearly shows that the photon index increased from ∼1.72 to ∼1.80 as the flux increased by nearly a factor of two. We discuss the results in the framework of the fluctuation propagation model.« less
Current Perspectives in High Energy Astrophysics

NASA Technical Reports Server (NTRS)

Ormes, Jonathan F. (Editor)

1996-01-01

High energy astrophysics is a space-age discipline that has taken a quantum leap forward in the 1990s. The observables are photons and particles that are unable to penetrate the atmosphere and can only be observed from space or very high altitude balloons. The lectures presented as chapters of this book are based on the results from the Compton Gamma-Ray Observatory (CGRO) and Advanced Satellite for Cosmology and Astrophysics (ASCA) missions to which the Laboratory for High Energy Astrophysics at NASA's Goddard Space Flight Center made significant hardware contributions. These missions study emissions from very hot plasmas, nuclear processes, and high energy particle interactions in space. Results to be discussed include gamma-ray beaming from active galactic nuclei (AGN), gamma-ray emission from pulsars, radioactive elements in the interstellar medium, X-ray emission from clusters of galaxies, and the progress being made to unravel the gamma-ray burst mystery. The recently launched X-ray Timing Explorer (XTE) and prospects for upcoming Astro-E and Advanced X-ray Astronomy Satellite (AXAF) missions are also discussed.
Astro 101 Students' Perceptions of Science: Results from the "Thinking about Science Survey Instrument"

ERIC Educational Resources Information Center

Wallace, Colin S.; Prather, Edward E.; Mendelsohn, Benjamin M.

2013-01-01

What are the underlying worldviews and beliefs about the role of science in society held by students enrolled in a college-level, general education, introductory astronomy course (Astro 101)--and are those beliefs affected by active engagement instruction shown to significantly increase students' conceptual knowledge and reasoning abilities…
Astro Data Science: The Next Generation

NASA Astrophysics Data System (ADS)

Mentzel, Chris

2018-01-01

Astronomers have been at the forefront of data-driven discovery since before the days of Kepler. Using data in the scientific inquiry into the workings of the the universe is the lifeblood of the field. This said, data science is considered a new thing, and researchers from every discipline are rushing to learn data science techniques, train themselves on data science tools, and even leaving academia to become data scientists. It is undeniable that our ability to harness new computational and statistical methods to make sense of today’s unprecedented size, complexity, and fast streaming data is helping scientists make new discoveries. The question now is how to ensure that researchers can employ these tools and use them appropriately. This talk will cover the state of data science as it relates to scientific research and the role astronomers play in its development, use, and training the next generation of astro-data scientists.
American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) Practice Guideline for the Performance of High-Dose-Rate Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erickson, Beth A.; Demanes, D. Jeffrey; Ibbott, Geoffrey S.

2011-03-01

High-Dose-Rate (HDR) brachytherapy is a safe and efficacious treatment option for patients with a variety of different malignancies. Careful adherence to established standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and American Society for Therapeutic Radiation Oncology (ASTRO) has produced a practice guideline for HDR brachytherapy. The guideline defines the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrists. Review of the leading indications for HDR brachytherapy in the management of gynecologic, thoracic, gastrointestinal,more » breast, urologic, head and neck, and soft tissue tumors is presented. Logistics with respect to the brachytherapy implant procedures and attention to radiation safety procedures and documentation are presented. Adherence to these practice guidelines can be part of ensuring quality and safety in a successful HDR brachytherapy program.« less
Far-ultraviolet astronomy on the Astro-1 space shuttle mission

NASA Technical Reports Server (NTRS)

Davidsen, Arthur F.

1993-01-01

The Astro-1 mission obtained observations related to a wide variety of current problems in astronomy during a 9-day flight of the space shuttle Columbia. Early results from one of the instruments, the Hopkins Ultraviolet Telescope, are reviewed here. Among these are new insights concerning the origin of the ultraviolet light from the old stellar population in elliptical galaxies, new evidence for a hot, gaseous corona surrounding the Milky Way, improved views of the physical conditions in active galactic nuclei, and a measurement of the ionization state of the local interstellar medium.
AstroImageJ: Image Processing and Photometric Extraction for Ultra-precise Astronomical Light Curves

NASA Astrophysics Data System (ADS)

Collins, Karen A.; Kielkopf, John F.; Stassun, Keivan G.; Hessman, Frederic V.

2017-02-01

ImageJ is a graphical user interface (GUI) driven, public domain, Java-based, software package for general image processing traditionally used mainly in life sciences fields. The image processing capabilities of ImageJ are useful and extendable to other scientific fields. Here we present AstroImageJ (AIJ), which provides an astronomy specific image display environment and tools for astronomy specific image calibration and data reduction. Although AIJ maintains the general purpose image processing capabilities of ImageJ, AIJ is streamlined for time-series differential photometry, light curve detrending and fitting, and light curve plotting, especially for applications requiring ultra-precise light curves (e.g., exoplanet transits). AIJ reads and writes standard Flexible Image Transport System (FITS) files, as well as other common image formats, provides FITS header viewing and editing, and is World Coordinate System aware, including an automated interface to the astrometry.net web portal for plate solving images. AIJ provides research grade image calibration and analysis tools with a GUI driven approach, and easily installed cross-platform compatibility. It enables new users, even at the level of undergraduate student, high school student, or amateur astronomer, to quickly start processing, modeling, and plotting astronomical image data with one tightly integrated software package.
AstroCloud, a Cyber-Infrastructure for Astronomy Research: Overview

NASA Astrophysics Data System (ADS)

Cui, C.; Yu, C.; Xiao, J.; He, B.; Li, C.; Fan, D.; Wang, C.; Hong, Z.; Li, S.; Mi, L.; Wan, W.; Cao, Z.; Wang, J.; Yin, S.; Fan, Y.; Wang, J.

2015-09-01

AstroCloud is a cyber-Infrastructure for Astronomy Research initiated by Chinese Virtual Observatory (China-VO) under funding support from NDRC (National Development and Reform commission) and CAS (Chinese Academy of Sciences). Tasks such as proposal submission, proposal peer-review, data archiving, data quality control, data release and open access, Cloud based data processing and analyzing, will be all supported on the platform. It will act as a full lifecycle management system for astronomical data and telescopes. Achievements from international Virtual Observatories and Cloud Computing are adopted heavily. In this paper, backgrounds of the project, key features of the system, and latest progresses are introduced.
The Hitomi (ASTRO-H) Soft X-ray Telescope (SXT): current status of calibration

NASA Astrophysics Data System (ADS)

Maeda, Yoshitomo; Kikuchi, Naomichi; Kurashima, Sho; Ishida, Manabu; Iizuka, Ryo; Hayashi, Takayuki; Okajima, Takashi; Matsumoto, Hironori; Mitsuishi, Ikuyuki; Saji, Shigetaka; Sato, Toshiki; Tachibana, Sasagu; Mori, Hideyuki; Christensen, Finn; Brejnholt, Nicolai; Nitta, Kiyofumi; Uruga, Tomoya

2017-08-01

We report the atomic scattering factor in the 11.2-15.4 keV for the ASTRO-H Soft X-ray Telescope (SXT)9 obtained in the ground based measurements. The large effective area of the SXT covers above 10 keV. In fact, the flight data show the spectra of the celestical objects in the hard X-ray band. In order to model the area, the reflectivity measurements in the 11.2-15.4 keV band with the energy pitch of 0.4 - 0.7 eV were made in the synchrotron beamline Spring-8 BL01B1. We obtained atomic scattering factors f1 and f2 by the curve fitting to the reflectivities of our witness sample. The edges associated with the gold' s L-I, II, and III transitions are identified, of which the depths are found to be roughly 60% shallower than those expected from the Henke's atomic scattering factor.
Development of signal processing system of avalanche photo diode for space observations by Astro-H

NASA Astrophysics Data System (ADS)

Ohno, M.; Goto, K.; Hanabata, Y.; Takahashi, H.; Fukazawa, Y.; Yoshino, M.; Saito, T.; Nakamori, T.; Kataoka, J.; Sasano, M.; Torii, S.; Uchiyama, H.; Nakazawa, K.; Watanabe, S.; Kokubun, M.; Ohta, M.; Sato, T.; Takahashi, T.; Tajima, H.

2013-01-01

Astro-H is the sixth Japanese X-ray space observatory which will be launched in 2014. Two of onboard instruments of Astro-H, Hard X-ray Imager and Soft Gamma-ray Detector are surrounded by many number of large Bismuth Germanate (Bi4Ge3O12; BGO) scintillators. Optimum readout system of scintillation lights from these BGOs are essential to reduce the background signals and achieve high performance for main detectors because most of gamma-rays from out of field-of-view of main detectors or radio-isotopes produced inside them due to activation can be eliminated by anti-coincidence technique using BGO signals. We apply Avalanche Photo Diode (APD) for light sensor of these BGO detectors since their compactness and high quantum efficiency make it easy to design such large number of BGO detector system. For signal processing from APDs, digital filter and other trigger logics on the Field-Programmable Gate Array (FPGA) is used instead of discrete analog circuits due to limitation of circuit implementation area on spacecraft. For efficient observations, we have to achieve as low threshold of anti-coincidence signal as possible by utilizing the digital filtering. In addition, such anti-coincident signals should be sent to the main detector within 5 μs to make it in time to veto the A-D conversion. Considering this requirement and constraint from logic size of FPGA, we adopt two types of filter, 8 delay taps filter with only 2 bit precision coefficient and 16 delay taps filter with 8 bit precision coefficient. The data after former simple filter provides anti-coincidence signal quickly in orbit, and the latter filter is used for detail analysis after the data is down-linked.
Ultra-Flexible Thermal Bus for Use in the Astro-H Adiabatic Demagnetization Refrigerator

NASA Technical Reports Server (NTRS)

Kimball, Mark O.; Shirron, Peter J.

2015-01-01

The adiabatic demagnetization refrigerator (ADR) developed for the Astro-H Soft-X-ray Spectrometer (SXS) is a multi-stage solid-state cooler. It is capable of holding the SXS detector array at 0.050 K for greater than 24 hours with a recycle time of less than one hour. This quick recycle time relies upon high-conductivity thermal straps to couple the individual stages to a pair of heat switches without imposing a lateral load on the paramagnetic salt pills. To accomplish this we construct thermal straps using a technique of diffusion bonding together the ends of high-purity copper straps leaving the length between as individual foils. A thermal bus created this way has a thermal conductivity comparable to a solid strap of the equivalent thickness but with much-increased flexibility. The technique for selecting the base material, machining, cleaning, forming into final shape, and finally bonding together individual foils will be discussed along with examples of complete straps in various geometries.
The integration of astro-geodetic data observed with ACSYS to the local geoid models Istanbul-Turkey

NASA Astrophysics Data System (ADS)

Halicioglu, Kerem; Ozludemir, M. Tevfik; Deniz, Rasim; Ozener, Haluk; Albayrak, Muge; Ulug, Rasit; Basoglu, Burak

2017-04-01

Astro-geodetic deflections of the vertical components provide accurate and valuable information of Earth's gravity filed. Conventional methods require considerable effort and time whereas new methods, namely digital zenith camera systems (DZCS), have been designed to eliminate drawbacks of the conventional methods, such as observer dependent errors, long observation times, and to improve the observation accuracy. The observation principle is based on capturing star images near zenithal direction to determine astronomical coordinates of the station point with the integration of CCD, telescope, tiltmeters, and GNSS devices. In Turkey a new DZCS have been designed and tested on control network located in Istanbul, of which the geoid height differences were known with the accuracy of ±3.5 cm. Astro-geodetic Camera System (ACSYS) was used to determine the deflections of the vertical components with an accuracy of ±0.1 - 0.3 arc seconds, and results were compared with geoid height differences using astronomical levelling procedure. The results have also been compared with the ones calculated from global geopotential models. In this study the recent results of the first digital zenith camera system of Turkey are presented and the future studies are introduced such as the current developments of the system including hardware and software upgrades as well as the new observation strategy of the ACSYS. We also discuss the contribution and integration of the astro-geodetic deflections of the vertical components to the geoid determination studies in the light of information of current ongoing projects being operated in Turkey.
An Investigation on the Use of Different Centroiding Algorithms and Star Catalogs in Astro-Geodetic Observations

NASA Astrophysics Data System (ADS)

Basoglu, Burak; Halicioglu, Kerem; Albayrak, Muge; Ulug, Rasit; Tevfik Ozludemir, M.; Deniz, Rasim

2017-04-01

In the last decade, the importance of high-precise geoid determination at local or national level has been pointed out by Turkish National Geodesy Commission. The Commission has also put objective of modernization of national height system of Turkey to the agenda. Meanwhile several projects have been realized in recent years. In Istanbul city, a GNSS/Levelling geoid was defined in 2005 for the metropolitan area of the city with an accuracy of ±3.5cm. In order to achieve a better accuracy in this area, "Local Geoid Determination with Integration of GNSS/Levelling and Astro-Geodetic Data" project has been conducted in Istanbul Technical University and Bogazici University KOERI since January 2016. The project is funded by The Scientific and Technological Research Council of Turkey. With the scope of the project, modernization studies of Digital Zenith Camera System are being carried on in terms of hardware components and software development. Accentuated subjects are the star catalogues, and centroiding algorithm used to identify the stars on the zenithal star field. During the test observations of Digital Zenith Camera System performed between 2013-2016, final results were calculated using the PSF method for star centroiding, and the second USNO CCD Astrograph Catalogue (UCAC2) for the reference star positions. This study aims to investigate the position accuracy of the star images by comparing different centroiding algorithms and available star catalogs used in astro-geodetic observations conducted with the digital zenith camera system.
Clustering analysis of line indices for LAMOST spectra with AstroStat

NASA Astrophysics Data System (ADS)

Chen, Shu-Xin; Sun, Wei-Min; Yan, Qi

2018-06-01

The application of data mining in astronomical surveys, such as the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) survey, provides an effective approach to automatically analyze a large amount of complex survey data. Unsupervised clustering could help astronomers find the associations and outliers in a big data set. In this paper, we employ the k-means method to perform clustering for the line index of LAMOST spectra with the powerful software AstroStat. Implementing the line index approach for analyzing astronomical spectra is an effective way to extract spectral features for low resolution spectra, which can represent the main spectral characteristics of stars. A total of 144 340 line indices for A type stars is analyzed through calculating their intra and inter distances between pairs of stars. For intra distance, we use the definition of Mahalanobis distance to explore the degree of clustering for each class, while for outlier detection, we define a local outlier factor for each spectrum. AstroStat furnishes a set of visualization tools for illustrating the analysis results. Checking the spectra detected as outliers, we find that most of them are problematic data and only a few correspond to rare astronomical objects. We show two examples of these outliers, a spectrum with abnormal continuumand a spectrum with emission lines. Our work demonstrates that line index clustering is a good method for examining data quality and identifying rare objects.
Discovering Astronomy: An Astro 101 e-book

NASA Astrophysics Data System (ADS)

Shawl, Stephen J.; Byrd, Gene; Deustua, Susana E.; LoPresto, Michael C.

2016-01-01

Discovering Astronomy, now available in its 6th edition as an eText, has many advantages and features for your students. We have partnered with etextink.com and WebAssign.net to produce an affordable set of cost-saving options for your students. Also available is the Discovering Astronomy Activity Manual, which provides students with an active-learning experience.Our etext is device independent and thus accessible through any web browser. Americans with Disabilities Act compatibility provides access for all students. Hotlinks to outside sites provide further information for interested students. Lecture demonstration videos of important concepts, made specifically for this new edition, are embedded within the text as appropriate. Students can highlight text, take notes, and bookmark locations within the text. Important terms are linked to the glossary. Search capabilities allow students to easily find what they want.Instructors can interact with their students directly through the etext once the class roster has been provided. For example, instructors can embed assignments into their students' etext and add their own notes and updates, which are immediately visible to their students.Updates can be quickly made by us as new findings become available. For example, updates from New Horizons were added at the time of the closest approach to Pluto, and an update on the recent announcement of current water on Mars was added the day of the announcement.We will present results of our own experience with college and high school students' use of Discovering Astronomy in online courses.Details of the book, a sample chapter, and other information are available at discoveringastronomy.weebly.com.
The Quantitative Reasoning for College Science (QuaRCS) Assessment in non-Astro 101 Courses

NASA Astrophysics Data System (ADS)

Kirkman, Thomas W.; Jensen, Ellen

2016-06-01

The innumeracy of American students and adults is a much lamented educational problem. The quantitative reasoning skills of college students may be particularly addressed and improved in "general education" science courses like Astro 101. Demonstrating improvement requires a standardized instrument. Among the non-proprietary instruments the Quantitative Literacy and Reasoning Assessment[1] (QRLA) and the Quantitative Reasoning for College Science (QuaRCS) Assessment[2] stand out.Follette et al. developed the QuaRCS in the context of Astro 101 at University of Arizona. We report on QuaRCS results in different contexts: pre-med physics and pre-nursing microbiology at a liberal arts college. We report on the mismatch between students' contemporaneous report of a question's difficulty and the actual probability of success. We report correlations between QuaRCS and other assessments of overall student performance in the class. We report differences in attitude towards mathematics in these two different but health-related student populations .[1] QLRA, Gaze et al., 2014, DOI: http://dx.doi.org/10.5038/1936-4660.7.2.4[2] QuaRCS, Follette, et al., 2015, DOI: http://dx.doi.org/10.5038/1936-4660.8.2.2

Autonomous star sensor ASTRO APS: flight experience on Alphasat

NASA Astrophysics Data System (ADS)

Schmidt, U.; Fiksel, T.; Kwiatkowski, A.; Steinbach, I.; Pradarutti, B.; Michel, K.; Benzi, E.

2015-06-01

Jena-Optronik GmbH, located in Jena/Germany, has profound experience in designing and manufacturing star trackers since the early 80s. Today the company has a worldwide leading position in supplying geo-stationary and Earth observation satellites with robust and reliable star tracker systems. In the first decade of the new century Jena-Optronik received a development contract (17317/2003/F/WE) from the European Space Agency to establish the technologically challenging elements for which advanced star tracker technologies as CMOS Active Pixel Sensors were being introduced or were considered strategic. This activity was performed in the frame of the Alphabus large platform pre-development lead by ESA and the industrial Joint Project Team consisting of Astrium (now Airbus Defence and Space), Thales Alenia Space and CNES (Centre national d'études spatiales). The new autonomous star tracker, ASTRO APS (Active Pixel Sensor), extends the Jena-Optronik A stro-series CCD-based star tracker products taken the full benefit of the CMOS APS technology. ASTRO APS is a fully autonomous compact star tracker carrying either the space-qualified radiation hard STAR1000 or the HAS2 APS detectors. The star tracker is one of four Technology Demonstration Payloads (TDP6) carried by Alphasat as hosted payload in the frame of a successful Private Public Partnership between ESA and Inmarsat who owns and operates the satellite as part of its geo-stationary communication satellites fleet. TDP6 supports also directly TDP1, a Laser Communication Terminal, for fine pointing tasks. Alphasat was flawlessly brought in orbit at the end of July 2013 by a European Ariane 5 launcher. Only a few hours after launch the star tracker received its switch ON command and acquired nominally within 6 s the inertial 3-axes attitude. In the following days of the early in-orbit operations of Alphasat the TDP6 unit tracked reliably all the spacecraft maneuvers including the 0.1 and 0.2°/s spin stabilization for
High-resolution x-ray spectroscopy with the EBIT Calorimeter Spectrometer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Porter, F. Scott; Adams, Joseph S.; Kelley, Richard L.

The EBIT Calorimeter Spectrometer (ECS) is a production-class 36 pixel x-ray calorimeter spectrometer that has been continuously operating at the Electron Beam Ion Trap (EBIT) facility at Lawrence Livermore National Laboratory for almost 2 years. The ECS was designed to be a long-lifetime, turn-key spectrometer that couples high performance with ease of operation and minimal operator intervention. To this end, a variant of the Suzaku/XRS spaceflight detector system has been coupled to a low-maintenance cryogenic system consisting of a long-lifetime liquid He cryostat, and a closed cycle, {sup 3}He pre-cooled adiabatic demagnetization refrigerator. The ECS operates for almost 3 weeksmore » between cryogenic servicing and the ADR operates at 0.05 K for more than 60 hours between automatic recycles under software control. Half of the ECS semiconductor detector array is populated with mid-band pixels that have a resolution of 4.5 eV FWHM, a bandpass from 0.05-12 keV, and a quantum efficiency of 95% at 6 keV. The other half of the array has thick HgTe absorbers that have a bandpass from 0.3 to over 100 keV, an energy resolution of 33 eV FWHM, and a quantum efficiency of 32% at 60 keV. In addition, the ECS uses a real-time, autonomous, data collection and analysis system developed for the Suzaku/XRS instrument and implemented in off-the-shelf hardware for the ECS. Here we will discuss the performance of the ECS instrument and its implementation as a turnkey cryogenic detector system.« less
The astro-geodetic use of CCD for gravity field refinement

NASA Astrophysics Data System (ADS)

Gerstbach, G.

1996-07-01

The paper starts with a review of geoid projects, where vertical deflections are more effective than gravimetry. In alpine regions the economy of astrogeoids is at least 10 times higher, but many countries do not make use of this fact - presumably because the measurements are not fully automated up to now. Based upon the experiences of astrometry of high satellites and own tests the author analyses the use of CCD for astro-geodetic measurements. Automation and speeding up will be possible in a few years, the latter depending on the observation scheme. Sensor characteristics, cooling and reading out of the devices should be harmonized. Using line sensors in small prism astrolabes, the CCD accuracy will reach the visual one (±0.2″) within 5-10 years. Astrogeoids can be combined ideally with geological data, because vertical variation of rock densities does not cause systematic effects (contrary to gravimetry). So a geoid of ±5 cm accuracy (achieved in Austria and other alpine countries by 5-10 points per 1000 km 2) can be improved to ±2 cm without additional observations and border effects.
In-Flight Performance of the Soft X-Ray Spectrometer Detector System on ASTRO-H

NASA Technical Reports Server (NTRS)

Porter, Frederick S.; Boyce, Kevin R.; Chiao, Meng P.; Eckart, Megan E.; Fujimoto, Ryuichi; Ishisaki, Yoshitaka; Kelley, Richard L.; Kilbourne, Carolina A.; Leutenegger, Maurice A.; McCammon, Dan;

2016-01-01

The SXS instrument was launched aboard the Astro-H observatory on February 17, 2016. The SXS spectrometer is based on a high sensitivity x-ray calorimeter detector system that has been successfully deployed in many ground and sub-orbital spectrometers. The instrument was to provide essential diagnostics for nearly every class of x-ray emitting objects from the atmosphere of Jupiter to the outskirts of galaxy clusters, without degradation for spatially extended objects. The SXS detector system consisted of a 36-pixel cryogenic microcalorimeter array operated at a heat sink temperature of 50 mK. In pre-flight testing, the detector system demonstrated a resolving power of better than 1300 at 6 keV with a simultaneous band-pass from below 0.3 keV to above 12 keV with a timing precision better than 100 microsecond. In addition, a solid-state anti-coincidence detector was placed directly behind the detector array for background suppression. The detector error budget included the measured interference from the SXS cooling system and the spacecraft. Additional margin for on-orbit gain-stability, and on-orbit spacecraft interference were also included predicting an on-orbit performance that meets or exceeds the 7 eV FWHM at 6 keV requirement. The actual on-orbit spectral resolution was better than 5 eV FWHM at 6 keV, easily satisfying the instrument requirement. Here we discuss the actual on-orbit performance of the SXS detector system and compare this to performance in pre-flight testing and the on-orbit predictions. We will also discuss the on-orbit gain stability, additional on-orbit interference, and measurements of the on-orbit background.

In-flight performance of the soft x-ray spectrometer detector system on Astro-H

NASA Astrophysics Data System (ADS)

Porter, Frederick S.; Boyce, Kevin R.; Chiao, Meng P.; Eckart, Megan E.; Fujimoto, Ryuichi; Ishisaki, Yoshitaka; Kilbourne, Caroline Anne; Leutenegger, Maurice A.; McCammon, Daniel; Mitsuda, Kazuhisa; Sato, Kosuke; Seta, Hiromi; Sawada, Makoto; Sneiderman, Gary A.; Szymkowiak, Andrew E.; Takei, Yoh; Tashiro, Makoto S.; Tsujimoto, Masahiro; Watanabe, Tomomi; Yamada, Shinya

2018-01-01

The soft x-ray spectrometer (SXS) instrument was launched aboard the Astro-H (Hitomi) observatory on February 17, 2016. The SXS is based on a high-sensitivity x-ray calorimeter detector system that has been successfully deployed in many ground and suborbital spectrometers. The instrument was to provide essential diagnostics for nearly every class of x-ray emitting objects from the atmosphere of Jupiter to the outskirts of galaxy clusters, without degradation for spatially extended objects. The SXS detector system consisted of a 36-pixel cryogenic microcalorimeter array operated at a heat sink temperature of 50 mK. In preflight testing, the detector system demonstrated a resolving power of better than 1300 at 6 keV with a simultaneous bandpass from below 0.3 keV to above 12 keV with a timing precision better than 100 μs. In addition, a solid-state anticoincidence detector was placed directly behind the detector array for background suppression. The detector error budget included the measured interference from the SXS cooling system and the spacecraft. Additional margin for on-orbit gain stability and on-orbit spacecraft interference were also included predicting an on-orbit performance that meets or exceeds the 7-eV FWHM at 6-keV requirement. The actual on-orbit spectral resolution was better than 5 eV FWHM at 6 keV, easily satisfying the instrument requirement. Here, we discuss the actual on-orbit performance of the SXS detector system and compare this to performance in preflight testing and the on-orbit predictions. We will also discuss the on-orbit gain stability, additional on-orbit interference, and measurements of the on-orbit background.
Creating Interactive Teaching Methods for ASTRO 101 That Really Work

NASA Astrophysics Data System (ADS)

Prather, E. E.; Adams, J. P.; Bailey, J. M.; Huggins, D.; Jones, L. V.; Slater, T. F.

2004-05-01

Acknowledging that lecture-based teaching methods are insufficient at promoting significant conceptual gains for students in the introductory astronomy course for non-science majors (ASTRO 101) is only the first step. But then, what can you do besides lecture? The Conceptual Astronomy and Physics Education Research (CAPER) Team at the University of Arizona has been developing and conducting research on the effectiveness of learner-centered instructional materials that put students in an active role in the classroom. With the support of an NSF CCLI (9952232) and NSF Geosciences Education (9907755) awards, we have designed and field-tested a set of innovative instructional materials called Lecture Tutorials. These Lecture Tutorial activities are intended for use with collaborative student learning groups and are designed specifically to be easily integrated into existing conventional lecture-based courses. As such, these instructional materials directly address the needs of heavily loaded teaching faculty in that they offer effective, learner-centered, classroom-ready activities that do not require any outside equipment/staffing or a drastic course revision for implementation. Each 15-minute Lecture-Tutorial poses a carefully crafted sequence of conceptually challenging, Socratic-dialogue driven questions, along with graphs and data tables, all designed to encourage students to reason critically about conceptually challenging and commonly taught topics in astronomy. The materials are based on research into student beliefs and reasoning difficulties and make use of a conceptual change instructional framework that promotes the intellectual engagement of students. Our research into the effectiveness of the Lecture Tutorials illustrates that traditional lectures alone make unsatisfactory gains on student understanding; however, supplementing traditional instruction with the lecture tutorials helps students make impressive conceptual gains over traditional instruction. In
From Picas to Pixels: An Astro 101 e-book

NASA Astrophysics Data System (ADS)

Shawl, Stephen J.; Byrd, Gene G.; Deustua, Susana E.; LoPresto, Michael C.

2015-01-01

What to do when a publisher discontinues publishing a textbook? That was the dilemma we were presented with. Given that we know we have a high quality product that can contribute to student understanding of science in general and astronomy in particular, and that significant efforts had already been expended on the project, we decided to self-publish, even knowing that the challenges, and the gamble in terms of time and personal expense, were great.Self publication provides an opportunity to produce an updated edition at great cost savings to students---something faculty often say is an important consideration in their choice of a book.We present the end result: a completed publication in various e-book formats and with links to the Discovering Astronomy Concept Videos made for the book. The Discovering Astronomy Activities Manual will again be available. Details of the book, a sample chapter, and other information are available at discoveringastronomy@weebly.com.
From Picas to Pixels: An Astro 101 e-Book

NASA Astrophysics Data System (ADS)

Shawl, S.; Byrd, G.; Deustua, S.; LoPresto, M.

2015-11-01

What happens when a publisher discontinues publishing a textbook? That was the dilemma we were presented. Given that we know we have a high quality product that can contribute to student understanding of science in general and astronomy in particular, and that significant efforts had already been expended on the project, we decided to self-publish, even knowing that the challenges, and the gamble in terms of time and personal expense, were great. Self publication provides an opportunity to produce an updated edition at great cost savings to students— something faculty often say is an important consideration in their choice of a book. We discuss the many significant challenges, the greatest of which is marketing. We present the end result: a completed publication in various e-book formats and with links to the Discovering Astronomy Concept Videos made for the book (Figure 1). Details of the book, a sample chapter, and other information are available online.
The State-of-the-art HST Astro-photometric Analysis of the Core of ω Centauri. II. Differential-reddening Map

NASA Astrophysics Data System (ADS)

Bellini, A.; Anderson, J.; van der Marel, R. P.; King, I. R.; Piotto, G.; Bedin, L. R.

2017-06-01

We take advantage of the exquisite quality of the Hubble Space Telescope astro-photometric catalog of the core of ωCen presented in the first paper of this series to derive a high-resolution, high-precision, high-accuracy differential-reddening map of the field. The map has a spatial resolution of 2 × 2 arcsec2 over a total field of view of about 4.‧3 × 4.‧3. The differential reddening itself is estimated via an iterative procedure using five distinct color-magnitude diagrams, which provided consistent results to within the 0.1% level. Assuming an average reddening value E(B - V) = 0.12, the differential reddening within the cluster’s core can vary by up to ±10%, with a typical standard deviation of about 4%. Our differential-reddening map is made available to the astronomical community in the form of a multi-extension FITS file. This differential-reddening map is essential for a detailed understanding of the multiple stellar populations of ωCen, as presented in the next paper in this series. Moreover, it provides unique insight into the level of small spatial-scale extinction variations in the Galactic foreground. Based on archival observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.
SSM on AstroSat detects neutron star X-ray transient, Aql_X-1 in its outburst

NASA Astrophysics Data System (ADS)

Ramadevi, M. C.; Ravishankar, B. T.; Sarwade, Abhilash R.; Vaishali, S.; Hasan, Mohammed; Agarwal, Vivek Kumar; Baby, Blessy Elizabeth; Bhattacharya, Dipankar; Seetha, S.; Agarwal, Anil

2017-06-01

We report on the X-ray outburst of the neutron star X-ray source Aql X-1 as observed by SSM onboard AstroSat. Flux reported by SSM on its first observation of the source during this outburst on 01 June 2017 at 08:55 UT is about 820 milliCrab (2.24 +/- 0.02 photons/s-cm^2).
X-ray Raman scattering for structural investigation of silica/silicate minerals

NASA Astrophysics Data System (ADS)

Fukui, H.; Kanzaki, M.; Hiraoka, N.; Cai, Y. Q.

2009-03-01

We have performed X-ray Raman scattering (XRS) measurements on the oxygen K and silicon L absorption edges of four silica minerals: α-quartz, α-cristobalite, coesite, and stishovite. We have also calculated the partial electron densities of states (DOSs) and compared these with the XRS spectra. This study demonstrates that the short-range structure around the atom of interest strongly influences the XRS spectral features. Importantly, the oxygen K-edge XRS spectra are found to reflect the p-orbital DOS while the silicon L-edge spectra reflect the s- and d-orbital DOSs, even when a product of a momentum transfer and a mean radius of a electron orbit (1 s for oxygen and 2 p for silicon), Qr, is close to or larger than unity. Building on this, calculations of the partial DOSs for other silica phases are presented, including ultra-high-pressure phases, which provide a good reference for further XRS study of silica and silicate minerals. XRS measurements should be performed on not only either of oxygen or silicon but also on many kinds of constituent elements to reveal the structural change of glasses/melts of silicates under extreme conditions.
Development status of the mechanical cryocoolers for the Soft X-ray Spectrometer on board Astro-H

NASA Astrophysics Data System (ADS)

Sato, Yoichi; Sawada, Kenichiro; Shinozaki, Keisuke; Sugita, Hiroyuki; Nishibori, Toshiyuki; Sato, Ryota; Mitsuda, Kazuhisa; Yamasaki, Noriko Y.; Takei, Yoh; Goto, Ken; Nakagawa, Takao; Fujimoto, Ryuichi; Kikuchi, Kenichi; Murakami, Masahide; Tsunematsu, Shoji; Ootsuka, Kiyomi; Kanao, Kenichi; Narasaki, Katsuhiro

2014-11-01

Astro-H is the Japanese X-ray astronomy satellite to be launched in 2015. The Soft X-ray Spectrometer (SXS) on board Astro-H is a high energy resolution spectrometer utilizing an X-ray micro-calorimeter array, which is operated at 50 mK by the ADR with the 30 liter superfluid liquid helium. The mechanical cryocoolers, 4 K-class Joule Thomson (JT) cooler and 20 K-class double-staged Stirling (2ST) cooler, are key components of the SXS cooling system to extend the lifetime of LHe cryogen beyond 3 years as required. Higher reliability was therefore investigated with higher cooling capability based on the heritage of existing cryocoolers. As the task of assessing further reliability dealt with the pipe-choking phenomena by contaminant solidification of the on-orbit SMILES JT cryocooler, outgassing from materials and component parts used in the cryocoolers was measured quantitatively to verify the suppression of carbon dioxide gas by their storage process and predict the total accumulated carbon dioxide for long-term operation. A continuous running test to verify lifetime using the engineering model (EM) of the 4 K-JT cooler is underway, having operated for a total of 720 days as of June 2013 and showing no remarkable change in cooling performance. During the current development phase, prototype models (PM) of the cryocoolers were installed to the test SXS dewar (EM) to verify the overall cooling performance from room temperature to 50 mK. During the EM dewar test, the requirement to reduce the transmitted vibration from the 2ST cooler compressor was recognized as mitigating the thermal instability of the SXS microcalorimeter at 50 mK.
Target and (Astro-)WISE technologies Data federations and its applications

NASA Astrophysics Data System (ADS)

Valentijn, E. A.; Begeman, K.; Belikov, A.; Boxhoorn, D. R.; Brinchmann, J.; McFarland, J.; Holties, H.; Kuijken, K. H.; Verdoes Kleijn, G.; Vriend, W.-J.; Williams, O. R.; Roerdink, J. B. T. M.; Schomaker, L. R. B.; Swertz, M. A.; Tsyganov, A.; van Dijk, G. J. W.

2017-06-01

After its first implementation in 2003 the Astro-WISE technology has been rolled out in several European countries and is used for the production of the KiDS survey data. In the multi-disciplinary Target initiative this technology, nicknamed WISE technology, has been further applied to a large number of projects. Here, we highlight the data handling of other astronomical applications, such as VLT-MUSE and LOFAR, together with some non-astronomical applications such as the medical projects Lifelines and GLIMPS; the MONK handwritten text recognition system; and business applications, by amongst others, the Target Holding. We describe some of the most important lessons learned and describe the application of the data-centric WISE type of approach to the Science Ground Segment of the Euclid satellite.
Dynamics of Galaxy Clusters and Expectations from Astro-H

NASA Technical Reports Server (NTRS)

Markevitch, Maxim

2012-01-01

Galaxy clusters span a range of dynamical states, from violent mergers -- the most energetic events in the Universe -- to systems near hydrostatic equilibrium that allow us to map their dark matter distribution using X-ray observations of the intracluster gas. Accurate knowledge of the cluster physics, and in particular, the physics of the hot intracluster gas, is required to realize the full potential of clusters as cosmological probes. So far, we have been studying the cluster dynamics indirectly, deducing merger geometries, cluster masses, etc., using X-ray brightness and gas temperature mapping. For the first time, the calorimeter onboard Astro-H will provide direct measurements of line-of-sight velocities and turbulent broadening in the intracluster gas, testing many of our key assumptions about clusters. This talk will summarize expectations for cluster dynamic studies with this new instrument.
Fibercore AstroGain fiber: multichannel erbium doped fibers for optical space communications

NASA Astrophysics Data System (ADS)

Hill, Mark; Gray, Rebecca; Hankey, Judith; Gillooly, Andy

2014-03-01

Fibercore have developed AstroGainTM fiber optimized for multichannel amplifiers used in optical satellite communications and control. The fiber has been designed to take full advantage of the photo-annealing effect that results from pumping in the 980nm region. The proprietary trivalent structure of the core matrix allows optimum recovery following radiation damage to the fiber, whilst also providing a market leading Erbium Doped Fiber Amplifier (EDFA) efficiency. Direct measurements have been taken of amplifier efficiency in a multichannel assembly, which show an effective photo-annealing recovery of up to 100% of the radiation induced attenuation through excitation of point defects.
A simulation of the instrument pointing system for the Astro-1 mission

NASA Technical Reports Server (NTRS)

Whorton, M.; West, M.; Rakoczy, J.

1991-01-01

NASA has recently completed a shuttle-borne stellar ultraviolet astronomy mission known as Astro-1. A three axis instrument pointing system (IPS) was employed to accurately point the science instruments. In order to analyze the pointing control system and verify pointing performance, a simulation of the IPS was developed using the multibody dynamics software TREETOPS. The TREETOPS IPS simulation is capable of accurately modeling the multibody IPS system undergoing large angle, nonlinear motion. The simulation is documented and example cases are presented demonstrating disturbance rejection, fine pointing operations, and multiple target pointing and slewing of the IPS.
Reflectivity Around the Gold M-Edges of X-ray Reflector of the Soft X-Ray Telescope Onboard ASTRO-H

NASA Technical Reports Server (NTRS)

Kurashimaa, Sho; Furuzawa, Akihiro; Sato, Toshiki; Kikuchia, Naomichi; Nakaniwaa, Nozomi; Maeda, Yoshitomo; Ishida, Manabu; Izuka, Ryo; Okajima, Takashi; Mori, Hideyuki;

2016-01-01

The X-ray astronomy satellite ASTRO-H are equipped with two equivalent soft X-ray telescopes (SXT-I and SXT-S) which cover the energy band 0.3-12 keV. The X-ray reflectors of the SXTs are coated with a gold monolayer by means of the replication technique. A series of gold M absorption edges in the 2-4 keV band causes complex structures in the energy response of the SXTs. In the same band, there are astrophysically important emission lines from Si, Ar and S. Since the SXS has unprecedentedly high spectral resolution, we have measured the reflectivity around the gold M-edges in an extremely fine energy pitch at the synchrotron radiation facility KEK PF BL11-B, with the 2 eV pitch in 2100 eV to 4100 eV band that covers the entire series of the absorption edges (M-I through M-V) at grazing incident angles to the reflectors of 0.5, 0.8, 1.0, 1.2, 1.4 degree, and with a finer pitch of 0.25 eV in the 2200 eV to 2350 eV band where the two deepest M-IV and M-V edges are included. In the resultant reflectivity curves, we have clearly identified the fine structures associated with all the M-edges. Using these data, we calculated atomic scattering factor f1 as a function of X-ray energy, with which we have built the mirror response function which can be applied to the Suzaku spectra. As a result, we have found that discrepancy of the spectral model to the Suzaku data of 4U1630-472 (a black hole transient) and the Crab nebula around the M-edges are significantly reduced from those with the official Suzaku response.

The Saccharomyces cerevisiae Mre11-Rad50-Xrs2 complex promotes trinucleotide repeat expansions independently of homologous recombination.

PubMed

Ye, Yanfang; Kirkham-McCarthy, Lucy; Lahue, Robert S

2016-07-01

Trinucleotide repeats (TNRs) are tandem arrays of three nucleotides that can expand in length to cause at least 17 inherited human diseases. Somatic expansions in patients can occur in differentiated tissues where DNA replication is limited and cannot be a primary source of somatic mutation. Instead, mouse models of TNR diseases have shown that both inherited and somatic expansions can be suppressed by the loss of certain DNA repair factors. It is generally believed that these repair factors cause misprocessing of TNRs, leading to expansions. Here we extend this idea to show that the Mre11-Rad50-Xrs2 (MRX) complex of Saccharomyces cerevisiae is a causative factor in expansions of short TNRs. Mutations that eliminate MRX subunits led to significant suppression of expansions whereas mutations that inactivate Rad51 had only a minor effect. Coupled with previous evidence, this suggests that MRX drives expansions of short TNRs through a process distinct from homologous recombination. The nuclease function of Mre11 was dispensable for expansions, suggesting that expansions do not occur by Mre11-dependent nucleolytic processing of the TNR. Epistasis between MRX and post-replication repair (PRR) was tested. PRR protects against expansions, so a rad5 mutant gave a high expansion rate. In contrast, the mre11 rad5 double mutant gave a suppressed expansion rate, indistinguishable from the mre11 single mutant. This suggests that MRX creates a TNR substrate for PRR. Protein acetylation was also tested as a mechanism regulating MRX activity in expansions. Six acetylation sites were identified in Rad50. Mutation of all six lysine residues to arginine gave partial bypass of a sin3 HDAC mutant, suggesting that Rad50 acetylation is functionally important for Sin3-mediated expansions. Overall we conclude that yeast MRX helps drive expansions of short TNRs by a mechanism distinct from its role in homologous recombination and independent of the nuclease function of Mre11. Copyright �
Large underground, liquid based detectors for astro-particle physics in Europe: scientific case and prospects

NASA Astrophysics Data System (ADS)

Autiero, D.; Äystö, J.; Badertscher, A.; Bezrukov, L.; Bouchez, J.; Bueno, A.; Busto, J.; Campagne, J.-E.; Cavata, Ch; Chaussard, L.; de Bellefon, A.; Déclais, Y.; Dumarchez, J.; Ebert, J.; Enqvist, T.; Ereditato, A.; von Feilitzsch, F.; Fileviez Perez, P.; Göger-Neff, M.; Gninenko, S.; Gruber, W.; Hagner, C.; Hess, M.; Hochmuth, K. A.; Kisiel, J.; Knecht, L.; Kreslo, I.; Kudryavtsev, V. A.; Kuusiniemi, P.; Lachenmaier, T.; Laffranchi, M.; Lefievre, B.; Lightfoot, P. K.; Lindner, M.; Maalampi, J.; Maltoni, M.; Marchionni, A.; Marrodán Undagoitia, T.; Marteau, J.; Meregaglia, A.; Messina, M.; Mezzetto, M.; Mirizzi, A.; Mosca, L.; Moser, U.; Müller, A.; Natterer, G.; Oberauer, L.; Otiougova, P.; Patzak, T.; Peltoniemi, J.; Potzel, W.; Pistillo, C.; Raffelt, G. G.; Rondio, E.; Roos, M.; Rossi, B.; Rubbia, A.; Savvinov, N.; Schwetz, T.; Sobczyk, J.; Spooner, N. J. C.; Stefan, D.; Tonazzo, A.; Trzaska, W.; Ulbricht, J.; Volpe, C.; Winter, J.; Wurm, M.; Zalewska, A.; Zimmermann, R.

2007-11-01

This document reports on a series of experimental and theoretical studies conducted to assess the astro-particle physics potential of three future large scale particle detectors proposed in Europe as next generation underground observatories. The proposed apparatuses employ three different and, to some extent, complementary detection techniques: GLACIER (liquid argon TPC), LENA (liquid scintillator) and MEMPHYS (water Cherenkov), based on the use of large mass of liquids as active detection media. The results of these studies are presented along with a critical discussion of the performance attainable by the three proposed approaches coupled to existing or planned underground laboratories, in relation to open and outstanding physics issues such as the search for matter instability, the detection of astrophysical neutrinos and geo-neutrinos and to the possible use of these detectors in future high intensity neutrino beams.
The Impact of an Authentic Science Experience on STEM Identity: A Preliminary Analysis of YouthAstroNet and MicroObservatory Telescope Network Participant Data

NASA Astrophysics Data System (ADS)

Dussault, Mary E.; Wright, Erika A.; Sadler, Philip; Sonnert, Gerhard; ITEAMS II Team

2018-01-01

Encouraging students to pursue careers in science, technology, engineering, and mathematics (STEM) is a high priority for national K-12 education improvement initiatives in the United States. Many educators have claimed that a promising strategy for nurturing early student interest in STEM is to engage them in authentic inquiry experiences. “Authentic” refers to investigations in which the questions are of genuine interest and importance to students, and the inquiry more closely resembles the way real science is done. Science education researchers and practitioners at the Harvard-Smithsonian Center for Astrophysics have put this theory into action with the development of YouthAstroNet, a nationwide online learning community of middle-school aged students, educators, and STEM professionals that features the MicroObservatory Robotic Telescope Network, professional image analysis software, and complementary curricula for use in a variety of learning settings. This preliminary study examines factors that influence YouthAstroNet participants' Science Affinity, STEM Identity, and STEM Career Interest, using the matched pre/post survey results of 261 participants as the data source. The pre/post surveys included some 40 items measuring affinity, identity, knowledge, and career interest. In addition, the post intervention instrument included a number of items in which students reported the instructional strategies they experienced as part of the program. A simple analysis of pre-post changes in affinity and interest revealed very little significant change, and for those items where a small pre-post effect was observed, the average change was most often negative. However, after accounting for students' different program treatment experiences and for their prior attitudes and interests, a predictor of significant student gains in Affinity, STEM Identity, Computer/Math Identity, and STEM Career Interest could be identified. This was the degree to which students reported

The Astro-H Soft X-Ray Mirror

NASA Technical Reports Server (NTRS)

Robinson, David; Okajima, Takashi; Serlemitsos, Peter; Soong, Yang

2012-01-01

The Astro-H is led by the Japanese Space Agency (JAXA) in collaboration with many other institutions including the NASA Goddard Space Flight Center. Goddard's contributions include two soft X-ray telescopes (SXTs). The telescopes have an effective area of 562 square cm at 1 keV and 425 square cm at 6 keV with an image quality requirement of 1.7 arc-minutes half power diameter (HPD). The engineering model has demonstrated 1.1 arc-minutes HPD error. The design of the SXT is based on the successful Suzaku mission mirrors with some enhancements to improve the image quality. Two major enhancements are bonding the X-ray mirror foils to alignment bars instead of allowing the mirrors to float, and fabricating alignment bars with grooves within 5 microns of accuracy. An engineering model SXT was recently built and subjected to several tests including vibration, thermal, and X-ray performance in a beamline. Several lessons were learned during this testing that will be incorporated in the flight design. Test results and optical performance are discussed, along with a description of the design of the SXT.
Teaching Your First Astro 101 Course: What They Don't Tell You

NASA Astrophysics Data System (ADS)

Bruning, D.

2014-07-01

Designing your Astro 101 course should not be about what topics you can omit but should be a thoughtful process that regards your fundamental teaching goals and which topics and skills promote those goals. Establishing goals and assessments that lead to measurable student outcomes enable one to more constructively design a learning experience for students. Just as any good novel has multiple story lines that weave throughout the book, your course has several narratives that wind through different topics and help to tie goals together. Sharing this underlying organizational structure of your course with students helps them to connect ideas and be more successful.
Atomic Scattering Factor of the ASTRO-H (Hitomi) SXT Reflector Around the Gold's L Edges

NASA Technical Reports Server (NTRS)

Kikuchi, Naomichi; Kurashima, Sho; Ishida, Manabu; Iizuka, Ryo; Maeda, Yoshitomo; Hayashi, Takayuki; Okajima, Takashi; Matsumoto, Hironori; Mitsubishi, Ikuyuki; Saji, Shigetaka

2016-01-01

The atomic scattering factor in the energy range of 11.2 - 15.4 keV for the ASTRO-H Soft X-ray Telescope (SXT) is reported. The large effective area of the SXT makes use of photon spectra above 10 keV viable, unlike most other X-ray satellites with total-reflection mirror optics. Presence of gold's L-edges in the energy band is a major issue, as it complicates the function of the effective area. In order to model the area, the reflectivity measurements in the 11.2 - 15.4 keV band with the energy pitch of 0.4 - 0.7 eV were made in the synchrotron beam-line Spring-8 BL01B1. We obtained atomic scattering factors f1 and f2 by the curve fitting to the reflectivities of our witness sample. The edges associated with the L-I, II, and III transitions are identified, of which the depths are found to be roughly 60 shallower than those expected from the Henkes atomic scattering factor.
On-Orbit Operation of the Adiabatic Demagnetization Refrigerator on the Astro-H/Hitomi Soft X-ray Spectrometer Instrument

NASA Technical Reports Server (NTRS)

Shirron, Peter; Kimball, Mark; James, Bryan; Muench, Theodore; Canavan, Edgar; DiPirro, Michael; Bialas, Thomas; Sneiderman, Gary; Boyce, Kevin; Kilbourne, Caroline;

2016-01-01

The Soft X-ray Spectrometer instrument on the Astro-H observatory contains a 6x6 array of x-ray microcalorimeters, which is cooled to 50 mK by an adiabatic demagnetization refrigerator (ADR). The ADR consists of three stages in order to provide stable detector cooling using either a 1.2 K superfluid helium bath or a 4.5 K Joule-Thomson (JT) cryocooler as its heat sink. When liquid helium is present, two of the ADRs stages are used to single-shot cool the detectors while rejecting heat to the helium. After the helium is depleted, all three stages are used to cool both the helium tank (to about 1.5 K) and the detectors (to 50 mK) using the JT cryocooler as its heat sink. The Astro-H observatory, renamed Hitomi after its successful launch in February 2016, carried approximately 36 liters of helium into orbit. On day 5, the helium had cooled sufficiently (1.4 K) to allow operation of the ADR. This paper describes the design, operation and on-orbit performance of the ADR.

iss042e292508

NASA Image and Video Library

2015-03-01

ISS042E292508 (03/01/2015) --- US astronaut Barry "Butch" Wilmore passes a cable to US astronaut Terry Virts during a spacewalk to install a new port for commercial spacecraft to dock to the International Space Station in the near future. Terry twitted this image on March 1, 2015 and remarked "Out on the P3 truss. #AstroButch handing me his cable to install on the new antenna. #spacewalk."
The Stocker AstroScience Center at Florida International University

NASA Astrophysics Data System (ADS)

Webb, James R.

2014-01-01

The new Stocker AstroScience Center located on the MMC campus at Florida International University in Miami Florida represents a unique facility for STEM education that arose from a combination of private, State and university funding. The building, completed in the fall of 2013, contains some unique spaces designed not only to educate, but also to inspire students interested in science and space exploration. The observatory consists of a 4-story building (3 floors) with a 24” ACE automated telescope in an Ash dome, and an observing platform above surrounding buildings. Some of the unique features of the observatory include an entrance/exhibition hall with a 6-ft glass tile floor mural linking the Florida climate to space travel, a state-of-the art telescope control that looks like a starship bridge, and displays such as “Music from the universe”. The observatory will also be the focus of our extensive public outreach program that is entering its 20 year.
ASTRO-1: a 1.8m unobscured space observatory for next generation UV/visible astrophysics and exoplanet exploration

NASA Astrophysics Data System (ADS)

Matthews, Gary W.; Egerman, Robert; Morse, Jon A.; Wilkes, Belinda

2016-07-01

The Hubble Space Telescope has been a scientific marvel that has provided unimaginable imagery and scientific discovery. Its exquisite UV/Visible imaging performance is unmatched from the ground. In NASA's future planning, the earliest possible successor mission would be in the 3030s, well beyond the expected lifetime of Hubble. The ASTRO-1 space telescope is a 1.8m off-axis (unobscured) observatory that looks to fill this critical void with Hubble-like performance to continue the scientific quest while also providing the possibility for exoplanet research with a coronagraphic instrument and/or a free flying starshade. BoldlyGo Institute seeks to reach beyond NASA funding to leverage the high public interest in space research and exploration, and the search for life beyond Earth.
Development and verification of signal processing system of avalanche photo diode for the active shields onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Ohno, M.; Kawano, T.; Edahiro, I.; Shirakawa, H.; Ohashi, N.; Okada, C.; Habata, S.; Katsuta, J.; Tanaka, Y.; Takahashi, H.; Mizuno, T.; Fukazawa, Y.; Murakami, H.; Kobayashi, S.; Miyake, K.; Ono, K.; Kato, Y.; Furuta, Y.; Murota, Y.; Okuda, K.; Wada, Y.; Nakazawa, K.; Mimura, T.; Kataoka, J.; Ichinohe, Y.; Uchida, Y.; Katsuragawa, M.; Yoneda, H.; Sato, G.; Sato, R.; Kawaharada, M.; Harayama, A.; Odaka, H.; Hayashi, K.; Ohta, M.; Watanabe, S.; Kokubun, M.; Takahashi, T.; Takeda, S.; Kinoshita, M.; Yamaoka, K.; Tajima, H.; Yatsu, Y.; Uchiyama, H.; Saito, S.; Yuasa, T.; Makishima, K.; ASTRO-H HXI/SGD Team

2016-09-01

The hard X-ray Imager and Soft Gamma-ray Detector onboard ASTRO-H demonstrate high sensitivity to hard X-ray (5-80 keV) and soft gamma-rays (60-600 keV), respectively. To reduce the background, both instruments are actively shielded by large, thick Bismuth Germanate scintillators. We have developed the signal processing system of the avalanche photodiode in the BGO active shields and have demonstrated its effectiveness after assembly in the flight model of the HXI/SGD sensor and after integration into the satellite. The energy threshold achieved is about 150 keV and anti-coincidence efficiency for cosmic-ray events is almost 100%. Installed in the BGO active shield, the developed signal processing system successfully reduces the room background level of the main detector.
The AstroBiology Explorer (ABE) MIDEX Mission: Using Infrared Spectroscopy to Identify Organic Molecules in Space

NASA Technical Reports Server (NTRS)

Sandford, S. A.

2002-01-01

The AstroBiology Explorer (ABE) mission is one of four selected for Phase A Concept Study in NASA's current call for MIDEX class missions. ABE is a cooled space telescope equipped with spectrographs covering the 2.5-20 micron spectral range. The ABE mission is devoted to the detection and identification of organic and related molecular species in space. ABE is currently under study at NASA's Ames Research Center in collaboration with Ball Aerospace.
The Hard X-ray Imager (HXI) for the ASTRO-H mission

NASA Astrophysics Data System (ADS)

Kokubun, Motohide; Nakazawa, Kazuhiro; Enoto, Teruaki; Fukazawa, Yasushi; Kataoka, Jun; Kawaharada, Madoka; Laurent, Philippe; Lebrun, François; Limousin, Olivier; Makishima, Kazuo; Mizuno, Tsunefumi; Mori, Kunishiro; Nakamori, Takeshi; Odaka, Hirokazu; Ohno, Masanori; Ohta, Masayuki; Sato, Goro; Sato, Rie; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takahashi, Tadayuki; Tanaka, Takaaki; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Watanabe, Shin; Yatsu, Yoichi; Yuasa, Takayuki

2012-09-01

The Hard X-ray Imager (HXI) is one of the four detectors on board the ASTRO-H mission (6th Japanese X-ray satellite), which is scheduled to be launched in 2014. Using the hybrid structure composed of double-sided silicon strip detectors and a cadmium telluride double-sided strip detector, both with a high spatial resolution of 250 μm. Combined with the hard X-ray telescope (HXT), it consists a hard X-ray imaging spectroscopic instrument covering the energy range from 5 to 80 keV with an effective area of <300 cm2 in total at 30 keV. An energy resolution of 1-2 keV (FWHM) and lower threshold of 5 keV are both achieved with using a low noise front-end ASICs. In addition, the thick BGO active shields surrounding the main detector package is a heritage of the successful performance of the Hard X-ray Detector on board the Suzaku satellite. This feature enables the instrument to achieve an extremely good reduction of background caused by cosmic-ray particles, cosmic X-ray background, and in-orbit radiation activation. In this paper, we present the detector concept, design, latest results of the detector development, and the current status of the hardware.
AstroSat/LAXPC Detection of Millisecond Phenomena in 4U 1728-34

NASA Astrophysics Data System (ADS)

Verdhan Chauhan, Jai; Yadav, J. S.; Misra, Ranjeev; Agrawal, P. C.; Antia, H. M.; Pahari, Mayukh; Sridhar, Navin; Dedhia, Dhiraj; Katoch, Tilak; Madhwani, P.; Manchanda, R. K.; Paul, B.; Shah, Parag

2017-05-01

The low-mass X-ray binary 4U 1728-24 was observed with AstroSat/LAXPC on 2016 March 8th. Data from a randomly chosen orbit of over 3 ks was analyzed for detection of rapid intensity variations. We found that the source intensity was nearly steady but, toward the end of the observation, a typical Type-1 burst was detected. Dynamical power spectrum of the data in the 3-20 keV band, reveals the presence of a kHz Quasi-Periodic Oscillation (QPO) for which the frequency drifted from ˜815 Hz at the beginning of the observation to about 850 Hz just before the burst. The QPO is also detected in the 10-20 keV band, which was not obtainable by earlier RXTE observations of this source. Even for such a short observation with a drifting QPO frequency, the time lag between the 5-10 and 10-20 keV bands can be constrained to be less than 100 microseconds. The Type-1 burst that lasted for about 20 s had a typical profile. During the first four seconds, dynamic power spectra reveal a burst oscillation for which the frequency increased from ˜361.5 to ˜363.5 Hz. This is consistent with the earlier results obtained with RXTE/PCA, showing the same spin frequency of the neutron star. The present results demonstrate the capability of the LAXPC instrument for detecting millisecond variability even from short observations. After RXTE ceased operation, LAXPC on AstroSat is the only instrument at present with the capability of detecting kHz QPOs and other kinds of rapid variations from 3 keV to 20 keV and possibly at higher energies as well.
American Society for Radiation Oncology (ASTRO) 2012 Workforce Study: The Radiation Oncologists' and Residents' Perspectives

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pohar, Surjeet, E-mail: spohar@iuhealth.org; Fung, Claire Y.; Hopkins, Shane

Purpose: The American Society for Radiation Oncology (ASTRO) conducted the 2012 Radiation Oncology Workforce Survey to obtain an up-to-date picture of the workforce, assess its needs and concerns, and identify quality and safety improvement opportunities. The results pertaining to radiation oncologists (ROs) and residents (RORs) are presented here. Methods: The ASTRO Workforce Subcommittee, in collaboration with allied radiation oncology professional societies, conducted a survey study in early 2012. An online survey questionnaire was sent to all segments of the radiation oncology workforce. Respondents who were actively working were included in the analysis. This manuscript describes the data for ROs andmore » RORs. Results: A total of 3618 ROs and 568 RORs were surveyed. The response rate for both groups was 29%, with 1047 RO and 165 ROR responses. Among ROs, the 2 most common racial groups were white (80%) and Asian (15%), and the male-to-female ratio was 2.85 (74% male). The median age of ROs was 51. ROs averaged 253.4 new patient consults in a year and 22.9 on-treatment patients. More than 86% of ROs reported being satisfied or very satisfied overall with their career. Close to half of ROs reported having burnout feelings. There was a trend toward more frequent burnout feelings with increasing numbers of new patient consults. ROs' top concerns were related to documentation, reimbursement, and patients' health insurance coverage. Ninety-five percent of ROs felt confident when implementing new technology. Fifty-one percent of ROs thought that the supply of ROs was balanced with demand, and 33% perceived an oversupply. Conclusions: This study provides a current snapshot of the 2012 radiation oncology physician workforce. There was a predominance of whites and men. Job satisfaction level was high. However a substantial fraction of ROs reported burnout feelings. Perceptions about supply and demand balance were mixed. ROs top concerns reflect areas of attention
Spectral and timing properties of atoll source 4U 1705-44: LAXPC/AstroSat results

NASA Astrophysics Data System (ADS)

Agrawal, V. K.; Nandi, Anuj; Girish, V.; Ramadevi, M. C.

2018-07-01

In this paper, we present the first results of spectral and timing properties of the atoll source 4U 1705-44 using ˜100 ks data obtained with the Large Area X-ray Proportional Counter (LAXPC) onboard AstroSat. The source was in the high soft state during our observations and traced out a banana track in the hardness intensity diagram (HID). We study the evolution of the power density spectra (PDS) and the energy spectra along the HID. PDS show the presence of a broad Lorentzian feature (peaked noise or PN) centred at 1-13 Hz and very low-frequency noise (VLFN). The energy spectra can be described by the sum of a thermal Comptonized component, a power-law and a broad iron line. The hard tail seen in the energy spectra is variable and contributes 4-30 per cent of the total flux. The iron line seen in this source is broad (FWHM ˜ 2 keV) and strong (EW ˜ 369-512 eV). Relativistic smearing in the accretion disc cannot explain the origin of this feature on its own and another mechanism is required, such as broadening by the Comptonization process in the external part of the `Comptonized corona'. A subtle and systematic evolution of the spectral parameters (optical depth, electron temperature etc.) is seen as the source moves along the HID. We study the correlation between the frequency of the PN and the spectral parameters. The PN frequency seems to be correlated with the strength of the corona. We discuss the implication of these results.
The State-of-the-art HST Astro-photometric Analysis of the Core of ω Centauri. I. The Catalog

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bellini, A.; Anderson, J.; Van der Marel, R. P.

We have constructed the most comprehensive catalog of photometry and proper motions ever assembled for a globular cluster (GC). The core of ω Cen has been imaged over 650 times through WFC3's UVIS and IR channels for the purpose of detector calibration. There exist from 4 to over 60 exposures through each of 26 filters stretching continuously from F225W in the UV to F160W in the infrared. Furthermore, the 11 yr baseline between these data and a 2002 ACS survey has allowed us to more than double the proper-motion accuracy and triple the number of well-measured stars compared to ourmore » previous groundbreaking effort. This totally unprecedented complete spectral coverage of over 470,000 stars within the cluster’s core, from the tip of the red giant branch down to the white dwarfs, provides the best astro-photometric observational database yet to understand the multiple-population phenomenon in any GC. In this first paper of the series, we describe in detail the data-reduction processes and deliver the astro-photometric catalog to the astronomical community.« less
Beyond Astro 101: A First Report on Applying Interactive Education Techniques to an Astronphysics Class for Majors

NASA Astrophysics Data System (ADS)

Perrin, Marshall D.; Ghez, A. M.

2009-05-01

Learner-centered interactive instruction methods now have a proven track record in improving learning in "Astro 101" courses for non-majors, but have rarely been applied to higher-level astronomy courses. Can we hope for similar gains in classes aimed at astrophysics majors, or is the subject matter too fundamentally different for those techniques to apply? We present here an initial report on an updated calculus-based Introduction to Astrophysics class at UCLA that suggests such techniques can indeed result in increased learning for major students. We augmented the traditional blackboard-derivation lectures and challenging weekly problem sets by adding online questions on pre-reading assignments (''just-in-time teaching'') and frequent multiple-choice questions in class ("Think-Pair-Share''). We describe our approach, and present examples of the new Think-Pair-Share questions developed for this more sophisticated material. Our informal observations after one term are that with this approach, students are more engaged and alert, and score higher on exams than typical in previous years. This is anecdotal evidence, not hard data yet, and there is clearly a vast amount of work to be done in this area. But our first impressions strongly encourage us that interactive methods should be able improve the astrophysics major just as they have improved Astro 101.
STS-35 MS Hoffman operates ASTRO-1 MPC on OV-102's aft flight deck

NASA Image and Video Library

1990-12-10

STS035-12-015 (2-11 Dec 1990) --- Astronaut Jeffrey A. Hoffman, STS 35 mission specialist, uses a manual pointing controller (MPC) for the Astro-1 mission's Instrument Pointing System (IPS). By using the MPC, Hoffman and other crewmembers on Columbia's aft flight deck, were able to command the IPS, located in the cargo bay, to record astronomical data. Hoffman is serving the "Blue" shift which complemented the currently sleeping "Red" shift of crewmembers as the mission collected scientific data on a 24-hour basis. The scene was photographed with a 35mm camera.
Cryogenic Technology: Ongoing Developments for the Next Decade

NASA Technical Reports Server (NTRS)

DiPirro, Michael

2004-01-01

To obtain optimum sensitivity a submillimeter space observatory will require low temperature mirrors (approx. 3K) and very low temperature detectors (< or approx. 0.1 K). Both of these temperatures have been achieved by space cryogenic systems, but neither for a 10 year duration. Past systems used superfluid helium to provide direct cooling in the 1 to 2 K range (IRAS, COBE, IRTS, ISO) or as an upper stage for an adiabatic demagnetization refrigerator to achieve temperatures down to 0.06 K (Astro-E/XRS). Boiloff vapor may be used to cool an otherwise warm telescope as in the Space InfraRed Telescope Facility (SIRTF). In SIRTF a 0.85 m telescope is cooled to 5.5 K by absorbing about 6 mW in the cold vapor. This residual heat is due to both radiation from a helium vapor cooled outer shield at about 20 K and from conduction through a structure mounting the cold telescope and instruments to the warm spacecraft. The boil off rate required to cool the telescope results in a 2.6 to 5 year lifetime, depending on whether other parasitic heat sources such as thermoacoustic oscillations are also present. A helium dewar results in a very heavy system to achieve 2 to 5 year lifetimes. For example it takes roughly 400 kg for XRS to achieve 0.06 K for two year life with a 250 K boundary temperature, and approx. 300 kg (including thermal shielding) for SIRTF to achieve 1.3 K for 5 year life with a 35 K boundary temperature. To go to longer duration and to lower the weight, active cooling methods are required combined with more aggressive passive cooling techniques. It is possible, with some development, to provide cooling for detectors to 0.05 K and telescopes and instruments to < 4 K for a 10 year mission with a 100 kg system including power sources, structural support, and vacuum enclosures for critical portions of the instruments.
Lessons Learned through the Development and Publication of AstroImageJ

NASA Astrophysics Data System (ADS)

Collins, Karen

2018-01-01

As lead author of the scientific image processing software package AstroImageJ (AIJ), I will discuss the reasoning behind why we decided to release AIJ to the public, and the lessons we learned related to the development, publication, distribution, and support of AIJ. I will also summarize the AIJ code language selection, code documentation and testing approaches, code distribution, update, and support facilities used, and the code citation and licensing decisions. Since AIJ was initially developed as part of my graduate research and was my first scientific open source software publication, many of my experiences and difficulties encountered may parallel those of others new to scientific software publication. Finally, I will discuss the benefits and disadvantages of releasing scientific software that I now recognize after having AIJ in the public domain for more than five years.
Simulating Shock Triggered Star Formation with AstroBEAR2.0

NASA Astrophysics Data System (ADS)

Li, Shule; Frank, Adam; Blackman, Eric

2013-07-01

Star formation can be triggered by the compression from shocks running over stable clouds. Triggered star formation is a favored explanation for the traces of SLRI's in our solar system. Previous research has shown that when parameters such as shock speed are within a certain range, the gravitational collapse of otherwise stable, dense cloud cores is possible. However, these studies usually focus on the precursors of star formation, and the conditions for the triggering. We use AstroBEAR2.0 code to simulate the collapse and subsequent evolution of a stable Bonnor-Ebert cloud by an incoming shock. Through our simulations, we show that interesting physics happens when the newly formed star interacts with the cloud residue and the post-shock flow. We identify these interactions as controlled by the initial conditions of the triggering and study the flow pattern as well as the evolution of important physics quantities such as accretion rate and angular momentum.
Design, implementation, and performance of the Astro-H SXS calorimeter array and anticoincidence detector

NASA Astrophysics Data System (ADS)

Kilbourne, Caroline A.; Adams, Joseph S.; Brekosky, Regis P.; Chervenak, James A.; Chiao, Meng P.; Eckart, Megan E.; Figueroa-Feliciano, Enectali; Galeazzi, Masimilliano; Grein, Christoph; Jhabvala, Christine A.; Kelly, Daniel; Leutenegger, Maurice A.; McCammon, Dan; Scott Porter, F.; Szymkowiak, Andrew E.; Watanabe, Tomomi; Zhao, Jun

2018-01-01

The calorimeter array of the JAXA Astro-H (renamed Hitomi) soft x-ray spectrometer (SXS) was designed to provide unprecedented spectral resolution of spatially extended cosmic x-ray sources and of all cosmic x-ray sources in the Fe-K band around 6 keV, enabling essential plasma diagnostics. The SXS had a square array of 36 x-ray calorimeters at the focal plane. These calorimeters consisted of ion-implanted silicon thermistors and HgTe thermalizing x-ray absorbers. These devices demonstrated a resolution of better than 4.5 eV at 6 keV when operated at a heat-sink temperature of 50 mK. We will discuss the basic physical parameters of this array, including the array layout, thermal conductance of the link to the heat sink, resistance function, absorber details, and means of attaching the absorber to the thermistor-bearing element. We will also present the thermal characterization of the whole array, including thermal conductance and crosstalk measurements and the results of pulsing the frame temperature via alpha particles, heat pulses, and the environmental background. A silicon ionization detector was located behind the calorimeter array and served to reject events due to cosmic rays. We will briefly describe this anticoincidence detector and its performance.

AstroCom NYC: A Partnership to Support Underrepresented Minorities in Astronomy and Astrophysics Research and Education

NASA Astrophysics Data System (ADS)

Ford, K. E. Saavik; Paglione, Timothy; Robbins, Dennis; Mac Low, Mordecai-Mark; Agueros, Marcel A.

2015-01-01

AstroCom NYC is an NSF-funded partnership between astronomers at The City University of New York (CUNY), The American Museum of Natural History (AMNH) and Columbia University, designed to increase recruitment and retention of underrepresented minorities in astronomy and astrophysics. I will discuss the major program elements, including: recruitment, student selection, a 'Methods of Scientific Research' (MSR) course, summer research experience and ongoing structured mentoring. I will also discuss how the programs are integrated into each institution and present progress updates from our first two years.
Planning and Scheduling of Payloads of AstroSat During Initial and Normal Phase Observations

NASA Astrophysics Data System (ADS)

Pandiyan, R.; Subbarao, S. V.; Nagamani, T.; Rao, Chaitra; Rao, N. Hari Prasad; Joglekar, Harish; Kumar, Naresh; Dumpa, Surya Ratna Prakash; Chauhan, Anshu; Dakshayani, B. P.

2017-06-01

On 28th September 2015, India launched its first astronomical space observatory AstroSat, successfully. AstroSat carried five astronomy payloads, namely, (i) Cadmium Zinc Telluride Imager (CZTI), (ii) Large Area X-ray Proportional Counter (LAXPC), (iii) Soft X-ray Telescope (SXT), (iv) Ultra Violet Imaging Telescope (UVIT) and (v) Scanning Sky Monitor (SSM) and therefore, has the capability to observe celestial objects in multi-wavelength. Four of the payloads are co-aligned along the positive roll axis of the spacecraft and the remaining one is placed along the positive yaw axis direction. All the payloads are sensitive to bright objects and specifically, require avoiding bright Sun within a safe zone of their bore axes in orbit. Further, there are other operational constraints both from spacecraft side and payloads side which are to be strictly enforced during operations. Even on-orbit spacecraft manoeuvres are constrained to about two of the axes in order to avoid bright Sun within this safe zone and a special constrained manoeuvre is exercised during manoeuvres. The planning and scheduling of the payloads during the Performance Verification (PV) phase was carried out in semi-autonomous/manual mode and a complete automation is exercised for normal phase/Guaranteed Time Observation (GuTO) operations. The process is found to be labour intensive and several operational software tools, encompassing spacecraft sub-systems, on-orbit, domain and environmental constraints, were built-in and interacted with the scheduling tool for appropriate decision-making and science scheduling. The procedural details of the complex scheduling of a multi-wavelength astronomy space observatory and their working in PV phase and in normal/GuTO phases are presented in this paper.
Reflectivity around the gold L-edges of x-ray reflector of the soft x-ray telescope onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Maeda, Yoshitomo; Kikuchi, Naomichi; Kurashima, Sho; Ishida, Manabu; Iizuka, Ryo; Hayashi, Takayuki; Okajima, Takashi; Matsumoto, Hironori; Mitsuishi, Ikuyuki; Saji, Shigetaka; Sato, Toshiki; Tachibana, Sasagu; Mori, Hideyuki; Christensen, Finn; Brejnholt, Nicolai; Nitta, Kiyofumi; Uruga, Tomoya

2016-07-01

We report the atomic scattering factor in the 11.2{15.4 keV for the ASTRO-H Soft X-ray Telescope (SXT)9 obtained in the ground based measurements. The large effective area of the SXT covers above 10 keV. In fact, the flight data show the spectra of the celestical objects in the hard X-ray band. In order to model the area, the reflectivity measurements in the 11.2{15.4 keV band with the energy pitch of 0.4 { 0.7 eV were made in the synchrotron beamline Spring-8 BL01B1. We obtained atomic scattering factors f1 and f2 by the curve fitting to the reflectivities of our witness sample. The edges associated with the gold's L-I, II, and III transitions are identified, of which the depths are found to be roughly 60% shallower than those expected from the Henke's atomic scattering factor.
Reflectivity Around the Gold L-Edges of X-Ray Reflector of the Soft X-Ray Telescope Onboard ASTRO-H

NASA Technical Reports Server (NTRS)

Maeda, Yoshitomo; Kikuchi, Naomichi; Kurashima, Sho; Ishida, Manabu; Iizuka, Ryo; Hayashi, Takayuki; Okajima, Takashi; Matsumoto, Hironori; Mitsuishi, Ikuyuki; Saji, Shigetaka;

2016-01-01

We report the atomic scattering factor in the 11.215.4 keV for the ASTRO-H Soft X-ray Telescope (SXT) obtained in the ground based measurements. The large effective area of the SXT covers above 10 keV. In fact, the flight data show the spectra of the celestical objects in the hard X-ray band. In order to model the area, the reflectivity measurements in the 11.2-15.4 keV band with the energy pitch of 0.4-0.7 eV were made in the synchrotron beamline Spring-8 BL01B1. We obtained atomic scattering factors f1 and f2 by the curve fitting to the reflectivities of our witness sample. The edges associated with the golds L-I, II, and III transitions are identified, of which the depths are found to be roughly 60 percent shallower than those expected from the Henke's atomic scattering factor.

The State-of-the-art HST Astro-photometric Analysis of the Core of ω Centauri. I. The Catalog

NASA Astrophysics Data System (ADS)

Bellini, A.; Anderson, J.; Bedin, L. R.; King, I. R.; van der Marel, R. P.; Piotto, G.; Cool, A.

2017-06-01

We have constructed the most comprehensive catalog of photometry and proper motions ever assembled for a globular cluster (GC). The core of ωCen has been imaged over 650 times through WFC3's UVIS and IR channels for the purpose of detector calibration. There exist from 4 to over 60 exposures through each of 26 filters stretching continuously from F225W in the UV to F160W in the infrared. Furthermore, the 11 yr baseline between these data and a 2002 ACS survey has allowed us to more than double the proper-motion accuracy and triple the number of well-measured stars compared to our previous groundbreaking effort. This totally unprecedented complete spectral coverage of over 470,000 stars within the cluster's core, from the tip of the red giant branch down to the white dwarfs, provides the best astro-photometric observational database yet to understand the multiple-population phenomenon in any GC. In this first paper of the series, we describe in detail the data-reduction processes and deliver the astro-photometric catalog to the astronomical community. Based on archival observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555.
Clinical Implications of Oscillatory Lung Function during Methacholine Bronchoprovocation Testing of Preschool Children

PubMed Central

Choi, Sun Hee; Sheen, Youn Ho; Kim, Mi Ae; Baek, Ji Hyeon; Baek, Hey Sung; Lee, Seung Jin; Yoon, Jung Won; Rha, Yeong Ho

2017-01-01

Objective To investigate the repeatability and safety of measuring impulse oscillation system (IOS) parameters and the point of wheezing during bronchoprovocation testing of preschool children. Methods Two sets of methacholine challenge were conducted in 36 asthma children. The test was discontinued if there was a significant change in reactance (Xrs5) and resistance (Rrs5) at 5 Hz (Condition 1) or respiratory distress due to airway obstruction (Condition 2). The repeatability of PC80_Xrs5, PC30_Rrs5, and wheezing (PCw) was assessed. The changes in Z-scores and SD-indexes from prebaseline (before testing) to postbaseline (after bronchodilator) were determined. Results For PC30_Rrs5, PC80_Xrs5, and PCw for subjects, PC80_Xrs5 showed the highest repeatability. Fifteen of 70 tests met Condition 2. The changes from pre- and postbaseline values varied significantly for Rrs5 and Xrs5. Excluding subjects with Z-scores higher than 2SD, we were able to detect 97.1% of bronchial hyperresponsiveness during methacholine challenge based on the change in Rrs5 or Xrs5. A change in IOS parameters was associated with wheezing at all frequencies. Conclusion Xrs5 and Rrs5 have repeatability comparable with FEV1, and Xrs5 is more reliable than Rrs5. Clinicians can safely perform a challenge test by measuring the changes in Rrs5, Xrs5, and Z-scores from the prebaseline values. PMID:28740854
The Role of Astro-Geodetic in Precise Guidance of Long Tunnels

NASA Astrophysics Data System (ADS)

Mirghasempour, M.; Jafari, A. Y.

2015-12-01

One of prime aspects of surveying projects is guidance of paths of a long tunnel from different directions and finally ending all paths in a specific place. This kind of underground surveying, because of particular condition, has some different points in relation to the ground surveying, including Improper geometry in underground transverse, low precise measurement in direction and length due to condition such as refraction, distinct gravity between underground point and corresponding point on the ground (both value and direction of gravity) and etc. To solve this problems, astro-geodetic that is part of geodesy science, can help surveying engineers. In this article, the role of astronomy is defined in two subjects: 1- Azimuth determination of directions from entrance and exit nets of tunnel and also calibration of gyro-theodolite to use them in Underground transvers: By astronomical methods, azimuth of directions can be determine with an accuracy of 0.5 arcsecond, whereas, nowadays, no gyroscope can measure the azimuth in this accuracy; For instance, accuracy of the most precise gyroscope (Gyromat 5000) is 1.2 cm over a distance of one kilometre (2.4 arcsecond). Furthermore, the calibration methods that will be mention in this article, have significance effects on underground transverse. 2- Height relation between entrance point and exit point is problematic and time consuming; For example, in a 3 km long tunnel ( in Arak- Khoram Abad freeway), to relate entrance point to exit point, it is necessary to perform levelling about 90 km. Other example of this boring and time consuming levelling is in Kerman tunnel. This tunnel is 36 km length, but to transfer the entrance point height to exit point, 150 km levelling is needed. According to this paper, The solution for this difficulty is application of astro-geodetic and determination of vertical deflection by digital zenith camera system TZK2-D. These two elements make possible to define geoid profile in terms of
STS-35 Astronomy Laboratory 1 (ASTRO-1) in OV-102's payload bay at KSC

NASA Image and Video Library

1990-05-07

S90-36708 (7 May 1990) --- STS-35 Astronomy Laboratory 1 (ASTRO-1) view shows its telescopes, instrument pointing system (IPS), and support equipment installed in Columbia's, Orbiter Vehicle (OV) 102's, payload bay (PLB) at the Kennedy Space Center (KSC) Orbiter Processing Facility (OPF). In the foreground is the Spacelab Pallet System (SPS) igloo. The stowed IPS with its three ultraviolet telescopes appears in the center of the picture. In the background, the Broad Band X Ray Telescope (BBXRT) two axis pointing system (TAPS) is barely visible. View provided by KSC with alternate number KSC-90PC-423.
The Hard X-ray Imager (HXI) for the ASTRO-H Mission

NASA Astrophysics Data System (ADS)

Sato, Goro; Kokubun, Motohide; Nakazawa, Kazuhiro; Enoto, Teruaki; Fukazawa, Yasushi; Harayama, Atsushi; Hayashi, Katsuhiro; Kataoka, Jun; Katsuta, Junichiro; Kawaharada, Madoka; Laurent, Philippe; Lebrun, François; Limousin, Olivier; Makishima, Kazuo; Mizuno, Tsunefumi; Mori, Kunishiro; Nakamori, Takeshi; Noda, Hirofumi; Odaka, Hirokazu; Ohno, Masanori; Ohta, Masayuki; Saito, Shinya; Sato, Rie; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takahashi, Tadayuki; Takeda, Shinichiro; Terada, Yukikatsu; Uchiyama, Hideki; Uchiyama, Yasunobu; Watanabe, Shin; Yamaoka, Kazutaka; Yatsu, Yoichi; Yuasa, Takayuki

2014-07-01

The 6th Japanese X-ray satellite, ASTRO-H, is scheduled for launch in 2015. The hard X-ray focusing imaging system will observe astronomical objects with the sensitivity for detecting point sources with a brightness of 1/100,000 times fainter than the Crab nebula at > 10 keV. The Hard X-ray Imager (HXI) is a focal plane detector 12 m below the hard X-ray telescope (HXT) covering the energy range from 5 to 80 keV. The HXI is composed of a stacked Si/CdTe semiconductor detector module and surrounding BGO scintillators. The latter work as active shields for efficient reduction of background events caused by cosmic-ray particles, cosmic X-ray background, and in-orbit radiation activation. In this paper, we describe the detector system, and present current status of flight model development, and performance of HXI using an engineering model of HXI.
NASA's Astro-Venture Engages Exceptional Students in Earth System Science Using Inquiry

NASA Astrophysics Data System (ADS)

Oguinn, C.

2003-12-01

Astro-Venture is an educational, interactive, multimedia Web environment highlighting NASA careers and astrobiology research in the areas of Astronomy, Geology, Biology and Atmospheric Sciences. Students in grades 5-8 role-play NASA careers, as they search for and design a planet with the necessary characteristics for human habitation. Astro-Venture uses online multimedia activities and off-line inquiry explorations to engage students in guided inquiry aligned with the 5 E inquiry model. This model has proven to be effective with exceptional students. Students are presented with the intellectual confrontation of how to design a planet and star system that would be able to meet their biological survival needs. This provides a purpose for the online and off-line explorations used throughout the site. Students first explore "what" conditions are necessary to support human habitability by engaging in multimedia training modules, which allow them to change astronomical, atmospheric, geological and biological aspects of the Earth and our star system and to view the effects of these changes on Earth. By focusing on Earth, students draw on their prior knowledge, which helps them to connect their new knowledge to their existing schema. Cause and effect relationships of Earth provide a concrete model from which students can observe patterns and generalize abstract results to an imagined planet. From these observations, students draw conclusions about what aspects allowed Earth to remain habitable. Once students have generalized needed conditions of "what" we need for a habitable planet, they conduct further research in off-line, standards-based classroom activities that also follow the inquiry model and help students to understand "why" we need these conditions. These lessons focus on standards-based concepts such as states of matter and the structure and movement of the Earth's interior. These lessons follow the inquiry structure commonly referred to as the five E's as
CAPER Team Innovations in Teaching and Learning in ASTRO 101

NASA Astrophysics Data System (ADS)

Slater, Timothy F.; Prather, E. E.; Bailey, J. M.; Bardar, E.; Brissenden, G.; Dokter, E. F.; Hudgins, D.; Keller, J.

2006-12-01

The Conceptual Astronomy and Physics Education Research (CAPER) Team, based at the University of Arizona but drawing on the collective expertise of astronomy educators around the world, is conducting scholarly research and developing instructional strategies in an effort to support high-quality astronomy teaching. One avenue of research is focused on creating and validating conceptual inventories that instructors can use to measure the effectiveness of their instructional interventions. We have recently completed new inventories in the topic areas of (1) light and spectra; (2) stars and stellar formation; and (3) planetary atmospheres and the greenhouse effect. In addition, we are using results from research on students’ naive beliefs and reasoning difficulties to development instructional strategies that promote a learner centered classroom. Our research into the effectiveness of two such curriculum projects (Lecture-Tutorials for Introductory Astronomy and Ranking Tasks for Introductory Astronomy) show that these curriculum result in statistically significant gains in student understanding across a broad range of topics, much greater than lecture alone. A third avenue of research centers on improving how ASTRO 101 is taught on a national level. Informed by our continual evaluation and fine tuning of different forms of collaborative group learning and peer instruction teaching strategies, we have developed a multi-day series of workshops that are designed to help faculty better implement innovative teaching strategies that promote a learner-centered teaching environment in the ASTO 101 large lecture course. The workshops are being assessed and iteratively improved through formative evaluation approaches aimed at determining to what extent they have a positive impact on classroom practice.
Study of X-ray transients with Scanning Sky Monitor (SSM) onboard AstroSat

NASA Astrophysics Data System (ADS)

Ramadevi, M. C.; Ravishankar, B. T.; Sarwade, Abhilash R.; Vaishali, S.; Iyer, Nirmal Kumar; Nandi, Anuj; Girish, V.; Agarwal, Vivek Kumar; Baby, Blessy Elizabeth; Hasan, Mohammed; Seetha, S.; Bhattacharya, Dipankar

2018-02-01

Scanning Sky Monitor (SSM) onboard AstroSat is an X-ray sky monitor in the energy range 2.5-10 keV. SSM scans the sky for X-ray transient sources in this energy range of interest. If an X-ray transient source is detected in outburst by SSM, the information will be provided to the astronomical community for follow-up observations to do a detailed study of the source in various other bands. SSM instrument, since its power-ON in orbit, has observed a number of X-ray sources. This paper discusses observations of few X-ray transients by SSM. The flux reported by SSM for few sources during its Performance Verification phase (PV phase) is studied and the results are discussed.
STS-35 ASTRO-1 telescopes documented in OV-102's payload bay (PLB)

NASA Image and Video Library

1990-12-10

STS035-13-008 (2-10 Dec. 1990) --- The various components of the Astro-1 payload are seen backdropped against the blue and white Earth in this 35mm scene photographed through Columbia's aft flight deck windows. Parts of the Hopkins Ultraviolet Telescope (HUT), Ultraviolet Imaging Telescope (UIT) and the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE) are visible on the Spacelab Pallet in the foreground. The Broad Band X-Ray Telescope (BBXRT) is behind this pallet and is not visible in this scene. The smaller cylinder in the foreground is the "Igloo," which is a pressurized container housing the Command and Data Management System, which interfaces with the in-cabin controllers to control the Instrument Pointing System (IPS) and the telescopes.
Useful marker of oscillatory lung function in methacholine challenge test-comparison of reactance and resistance with dose-response slope.

PubMed

Yoon, Jung Won; Shin, Youn Ho; Jee, Hye Mi; Chang, Sun Jung; Baek, Ji Hyeon; Choi, Sun Hee; Kim, Hyeong Yun; Han, Man Yong

2014-06-01

There are few studies focusing on the comparison of resistance (Rrs) and reactance (Xrs) in impulse oscillometry system (IOS) in the bronchial challenge test using dose-response slope (DRS), a quantitative index of bronchial hyperresponsiveness. We conducted a case-control study of 144 asthmatic and 218 non-asthmatic children to compare the diagnostic accuracy of two-point linear DRS for FEV1 , Rrs5 , and Xrs5 (DRS_FEV1 , DRS_Rrs5 , and DRS_Xrs5 ) and assessed various diagnostic cut-off points of provocation concentrations (PC) using receiver operating characteristic (ROC) curves. DRS_FEV1 had a stronger correlation with DRS_Xrs5 (r = 0.739, P < 0.001) than with DRS_Rrs5 (r = 0.652, P < 0.001) and the area under the ROC curves of DRS_Xrs5 (0.737) was similar to that of DRS_FEV1 (0.732) and higher than that of DRS_Rrs5 (0.668). The area under the ROC curves in order of greater value was as follows: absolute change of Xrs5 (Abs_Xrs5 ) (0.759) > percent change of FEV1 (Pch_FEV1 ) (0.735) > Pch_Xrs5 (0.727) > Abs_Rrs5 (0.690) > Pch_Rrs5 (0.630). PC78 _Xrs5 and PC0.17 _Xrs5 of IOS showed considerably good sensitivity and specificity comparable to those of PC20 _FEV1 by spirometry. Additional 18 (13%) children who showed normal spirometric measures were identified as asthmatics with the use of IOS. The utility of the DRS_Xrs5 to differentiate asthmatics from controls was comparable to that of the DRS_FEV1 and better than that of the DRS_Rrs5 . In addition, IOS could detect additional asthmatic patients who did not show positive responses in spirometry. © 2013 Wiley Periodicals, Inc.
Efficient parallelization for AMR MHD multiphysics calculations; implementation in AstroBEAR

NASA Astrophysics Data System (ADS)

Carroll-Nellenback, Jonathan J.; Shroyer, Brandon; Frank, Adam; Ding, Chen

2013-03-01

Current adaptive mesh refinement (AMR) simulations require algorithms that are highly parallelized and manage memory efficiently. As compute engines grow larger, AMR simulations will require algorithms that achieve new levels of efficient parallelization and memory management. We have attempted to employ new techniques to achieve both of these goals. Patch or grid based AMR often employs ghost cells to decouple the hyperbolic advances of each grid on a given refinement level. This decoupling allows each grid to be advanced independently. In AstroBEAR we utilize this independence by threading the grid advances on each level with preference going to the finer level grids. This allows for global load balancing instead of level by level load balancing and allows for greater parallelization across both physical space and AMR level. Threading of level advances can also improve performance by interleaving communication with computation, especially in deep simulations with many levels of refinement. While we see improvements of up to 30% on deep simulations run on a few cores, the speedup is typically more modest (5-20%) for larger scale simulations. To improve memory management we have employed a distributed tree algorithm that requires processors to only store and communicate local sections of the AMR tree structure with neighboring processors. Using this distributed approach we are able to get reasonable scaling efficiency (>80%) out to 12288 cores and up to 8 levels of AMR - independent of the use of threading.
The Effect of Lung Stretch during Sleep on Airway Mechanics in Overweight and Obese Asthma

PubMed Central

Campana, L.M.; Malhotra, A.; Suki, B.; Hess, L.; Israel, E.; Smales, E.; DeYoung, P.; Owens, R.L.

2012-01-01

Both obesity and sleep reduce lung volume and limit deep breaths, possibly contributing to asthma. We hypothesize that increasing lung volume dynamically during sleep would reduce airway resistance in asthma. Asthma (n=10) and control (n=10) subjects were studied during sleep at baseline and with increased lung volume via bi-level positive airway pressure (BPAP). Using forced oscillations, respiratory system resistance (Rrs) and reactance (Xrs) were measured during sleep and Rrs was partitioned to upper and lower airway resistance (Rup, Rlow) using an epiglottic pressure catheter. Rrs and Rup increased with sleep (p<0.01) and Xrs was decreased in REM (p=0.02) as compared to wake. Rrs, Rup, and Rlow, were larger (p<0.01) and Xrs was decreased (p<0.02) in asthma. On BPAP, Rrs and Rup were decreased (p<0.001) and Xrs increased (p<0.01), but Rlow was unchanged. High Rup was observed in asthma, which reduced with BPAP. We conclude that the upper airway is a major component of Rrs and larger lung volume changes may be required to alter Rlow. PMID:23041446
Learning by Teaching: Implementation of a Multimedia Project in Astro 101

NASA Astrophysics Data System (ADS)

Perrodin, D.; Lommen, A.

2011-09-01

Astro 101 students have deep-seated pre-conceptions regarding such topics as the cause of moon phases or the seasons. Beyond exploring the topics in a learner-centered fashion, the "learning by teaching" philosophy enables students to truly master concepts. In order to make students teach the cause of moon phases, we created a multimedia project where groups of students taught other students and filmed the session. They were to produce a 10-minute final movie highlighting their teaching techniques and showing students in the process of learning the concepts. This "experiment" turned out to be a great success for a few reasons. First, students gained experience explaining conceptually-challenging topics, making them learn the material better. Additionally, they learned to apply learner-centered techniques, most likely learning to teach for the first time. Finally, this project provided the students a connection between the classroom and the rest of the college, making them responsible for applying and sharing their knowledge with their peers.
First Peek of ASTRO-H Soft X-Ray Telescope (SXT) In-Orbit Performance

NASA Technical Reports Server (NTRS)

Okajima, Takashi; Soong, Yang; Serlemitsos, Peter J.; Mori, Hideyuki; Olsen, Lawrence; Robinson, David; Koenecke, Richard; Chang, William; Hahne, David; Iisuka, Ryo;

2016-01-01

ASTRO-H (Hitomi) is a Japanese X-ray astrophysics satellite just launched in February, 2016, from Tanegashima, Japan by a JAXA's H-IIA launch vehicle. It has two Soft X-ray Telescopes (SXTs), among other instruments, that were developed by the NASA Goddard Space Flight Center in collaboration with ISAS/JAXA and Nagoya University. One is for an X-ray micro-calorimeter instrument (Soft X-ray Spectrometer, SXS) and the other for an X-ray CCD camera (Soft X-ray Imager, SXI), both covering the X-ray energy band up to 15 keV. The two SXTs were fully characterized at the 30-m X-ray beam line at ISAS/JAXA. The combined SXT+SXS system effective area is about 250 and 300 cm(exp 2) at 1 and 6 keV, respectively, although observations were performed with the gate valve at the dewar entrance closed, which blocks most of low energy X-rays and some of high energy ones. The angular resolution for SXS is 1.2 arcmin (Half Power Diameter, HPD). The combined SXT+SXI system effective area is about 370 and 350 cm (exp 2) at 1 and 6 keV, respectively. The angular resolution for SXI is 1.3 arcmin (HPD). The both SXTs have a field of view of about 16 arcmin (FWHM of their vignetting functions).The SXT+SXS field of view is limited to 3 x 3 arcmin by the SXS array size. In-flight data available to the SXT team was limited at the time of this conference and a point-like source data is not available for the SXT+SXS. Although due to lack of attitude information we were unable to reconstruct a point spread function of SXT+SXI, according to RXJ1856.5-3754 data, the SXT seems to be working as expected in terms of imaging capability. As for the overall effective area response for both SXT+SXS and SXT+SXI, consistent spectral model fitting parameters with the previous measurements were obtained for Crab and G21.5-0.9 data. On the other hand, their 2-10 keV fluxes differ by about 20% at this point. Calibration work is still under progress. The SXT is the latest version of the aluminum foil X

ASTRO-H CdTe detectors proton irradiation at PIF

NASA Astrophysics Data System (ADS)

Limousin, O.; Renaud, D.; Horeau, B.; Dubos, S.; Laurent, P.; Lebrun, F.; Chipaux, R.; Boatella Polo, C.; Marcinkowski, R.; Kawaharada, M.; Watanabe, S.; Ohta, M.; Sato, G.; Takahashi, T.

2015-07-01

ASTRO-H will be operated in a Low Earth Orbit with a 31° inclination at 550 km altitude, thus passing daily through the South Atlantic Anomaly radiation belt, a specially harsh environment where the detectors are suffering the effect of the interaction with trapped high energy protons. As CdTe detector performance might be affected by the irradiation, we investigate the effect of the accumulated proton fluence on their spectral response. To do so, we have characterized and irradiated representative samples of SGD and HXI detector under different conditions. The detectors in question, from ACRORAD, are single-pixels having a size of 2 mm by 2 mm and 750 μm thick. The Schottky contact is either made of an Indium or Aluminum for SGD and HXI respectively. We ran the irradiation test campaign at the Proton Irradiation Facility (PIF) at PSI, and ESA approved equipment to evaluate the radiation hardness of flight hardware. We simulated the proton flux expected on the sensors over the entire mission, and secondary neutrons flux due to primary proton interactions into the surrounding BGO active shielding. We eventually characterized the detector response evolution, emphasizing each detector spectral response as well as its stability by studying the so-called Polarization effect. The latter is provoking a spectral response degradation against time as a charge accumulation process occurs in Schottky type CdTe sensors. In this paper, we report on the test campaigns at PIF and will show up our experimental setup. We will pursue describing the irradiation conditions associated with our GEANT 4 predictions and finally, we report the main results of our campaigns concluding that the proton effect does not severely affect the CdTe response neither the detector stability while the secondary neutrons might be more active to reduce the performance on the long run.
A Multi-Institution Study on the Effectiveness of ClassAction to Promote Student Understanding in Astro 101

NASA Astrophysics Data System (ADS)

Lee, Kevin M.; French, R. S.; Hands, D. R.; Loranz, D. R.; Martino, D.; Rudolph, A. L.; Wysong, J.; Young, T. S.; Prather, E. E.; CATS

2010-01-01

ClassAction is a computer database of materials designed to enhance the conceptual understanding and reasoning abilities of Astro 101 students by promoting interactive engagement and providing rapid feedback. The main focus is dynamic conceptual questions largely based upon graphics that can be projected in the classroom. Instructors have the capability to select, order, and recast these questions into alternate permutations based on their own preferences and student responses. Instructors may also provide feedback through extensive resources including outlines, graphics, and simulations. The Light and Spectroscopy Concept Inventory (LSCI) is a multiple-choice assessment instrument which focuses on the electromagnetic spectrum, Doppler shift, Wien's Law, Stefan-Boltzmann Law, and Kirchhoff's Laws. Illustrative examples of how these concepts are targeted by the questions and resources of the ClassAction module are shown. ClassAction materials covering light and spectra concepts were utilized in multiple classrooms at 6 different institutions and the LSCI was delivered as a pretest and posttest to measure the gains in student understanding. A comparison of the gains achieved in these classes will be made against the national LSCI data. We will report on our investigation into correlations between gain and the extent of ClassAction usage. ClassAction materials are publicly available at http://astro.unl.edu. We would like to thank the NSF for funding under Grant Nos. 0404988 and 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS) Program.

STS-35 Astronomy Laboratory 1 (ASTRO-1) in OV-102's payload bay at KSC

NASA Image and Video Library

1990-03-20

STS-35 Astronomy Laboratory 1 (ASTRO-1) is installed in Columbia's, Orbiter Vehicle (OV) 102's, payload bay (PLB) at the Kennedy Space Center (KSC) Orbiter Processing Facility (OPF). On the left, in the aft PLB is the Broad Band X Ray Telescope (BBXRT) mounted on the two axis pointing system (TAPS). In the center, the three ultraviolet telescopes - Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE), the Hopkins Ultraviolet Telescope (HUT), and the Ultraviolet Imaging Telescope (UIT) - are mounted on the instrument pointing system (IPS) and are in stowed position. At the far right is the Spacelab Pallet System (SPS) igloo. View provided by KSC with alternate number KSSC-90PC-421.
The Capabilities of the Graphical Observation Scheduling System (GROSS) as Used by the Astro-2 Spacelab Mission

NASA Technical Reports Server (NTRS)

Phillips, Shaun

1996-01-01

The Graphical Observation Scheduling System (GROSS) and its functionality and editing capabilities are reported on. The GROSS system was developed as a replacement for a suite of existing programs and associated processes with the aim of: providing a software tool that combines the functionality of several of the existing programs, and provides a Graphical User Interface (GUI) that gives greater data visibility and editing capabilities. It is considered that the improved editing capability provided by this approach enhanced the efficiency of the second astronomical Spacelab mission's (ASTRO-2) mission planning.
STS-35 ASTRO-1 telescopes documented in OV-102's payload bay (PLB)

NASA Image and Video Library

1990-12-10

STS035-604-058 (2-10 Dec 1990) --- The various components of the Astro-1 payload are seen backdropped against the blue and white Earth in this scene photographed through Columbia's aft flight deck windows. Parts of the Hopkins Ultraviolet Telescope (HUT), Ultraviolet Imaging Telescope (UIT) and the Wisconsin Ultraviolet Photopolarimetry Experiment (WUPPE) are visible on the Spacelab pallet in the foreground. The Broad Band X-ray Telescope (BBXRT) is behind this pallet and is not visible in this scene. The smaller cylinder in the foreground is the "Igloo," which is a pressurized container housing the Command and Data Management System, which interfaces with the in-cabin controllers to control the Instrument Pointing System (IPS) and the telescopes. The photograph was made with a handheld Rolleiflex camera aimed through Columbia's aft flight deck windows.
Solar X-Ray Irradiance Observations from the NOAA GOES Spacecraft: Accuracy vs Continuity

NASA Astrophysics Data System (ADS)

Viereck, R. A.; Machol, J. L.

2017-12-01

For 45 years, the solar X-Ray Sensors (XRS) on the GOES weather satellites have been making real-time measurements of the disk-integrated solar x-ray irradiance. These data have been remarkably consistent and contiguous and are the backbone of modern solar flare classification. When GOES 8 was launched in 1994, it observed 30% higher x-ray flux values compared to the earlier GOES. But no obvious cause of this offset was ever determined. For the sake of continuity, NOAA decided to adjust the GOES 8 data to match the old. We have been adjusting the XRS data on every GOES since (GOES 8-15). GOES 16 was launched in November of 2016 with a new XRS. This will be the first XRS that will have been fully calibrated with a primary calibration source so the values that it produces are presumed to be the most accurate yet. These new data show that our adjustment of the GOES 8 through 15 XRS data is not correct and that the true solar X-ray values are 30% higher than what has been reported for the last 45 years. In this presentation, we will show how the XRS sensors are characterized how the raw data are transformed into the science units that are presented to the public. We will present a plan on how to accurately present these new XRS values while maintaining continuity with the long record of XRS data.
Status and Future of GOES X-Ray Sensor Observations

NASA Astrophysics Data System (ADS)

Viereck, R.; Biesecker, D.

2008-05-01

The GOES X-Ray Sensor (XRS) has provided x-ray irradiance measurements in the 0.05 to 0.8 nm spectral band for nearly 30 years. These observations define the magnitude of x-ray flares. There are three issues that should be brought to the attention of the scientific community. First, today's XRS data have multiplicative factors of 0.7 and 0.85 that have been applied to the data to make recent (since GOES 8) observations match the earlier ones. We now believe that these factors are not correct and should be removed. There are implications on the magnitudes of flares and the historic record. The second issue is the current state of the XRS sensors. Two concurrent satellites, GOES 11 and GOES 12, now have failed XRS systems and the GOES 13 XRS (soon to be deployed) is only partially functioning leaving a serious vulnerability in the near future. The third issue is the future of these observations. From the beginning, the XRS detectors have been gas ionization cells which have proven to be very robust and stable. The future GOES R+ XRS instruments will be changing to solid state silicon diode detectors. The possible implications of this new detector technology should be considered as well. Details of these three issues will be presented and the implications discussed. Alternatives for the multiplicative factor and the failed XRS's will be presented.
Interaction between P2X and nicotinic acetylcholine receptors in glutamate nerve terminals of the rat hippocampus.

PubMed

Rodrigues, Ricardo J; Almeida, Teresa; de Mendonça, Alexandre; Cunha, Rodrigo A

2006-01-01

Nicotinic acetylcholine receptors (nAChRs [constituted by pentameric association of alpha2-10 and beta2-4 subunits]) and P2X receptors (P2XRs [activated by ATP and constituted by multimeric association of P2X1-7 subunits]) are both ionotropic receptors permeable to cations, which have in common the disparity between the wealth of data showing their presence in the brain and little evidence of their participation in mediating synaptic transmission. This has led to the proposal that both nAChRs and P2XRs might primarily modulate rather than directly mediate synaptic transmission, which is in accordance with the predominant presynaptic localization of both receptor subtypes (Role and Berg, 1996; Cunha and Ribeiro, 2000). Interestingly, both functional neurochemical (Allgaier et al., 1995; Salgado et al., 2000; Diáz-Hernández et al., 2002) and electrophysiological studies (Barajas-Lopez et al., 1998; Searl et al., 1998; Zhou and Calligan, 1998; Khakh et al., 2000) indicated a close interaction between nAChRs and P2XRs, which is paralleled by a co-release of ATPand ACh from central terminals (e.g., Richardson and Brown, 1987). Because glutamate release in the hippocampus is controlled by both nAChRs (e.g., McGehee et al., 1995) and P2XRs (Khakh et al., 2003; Rodrigues et al., 2005), we investigated if there was a functional interaction between these two presynaptic ionotropic receptors in the control of glutamate release in the rat hippocampus.
Mechanical design of a 3-stage ADR for the Astro-H mission

NASA Astrophysics Data System (ADS)

James, Bryan L.; Martinez, Raul M.; Shirron, Peter; Tuttle, Jim; Francis, John J.; San Sebastian, Marcelino; Wegel, Donald C.; Galassi, Nicholas M.; McGuinness, Daniel S.; Puckett, David; Flom, Yury

2012-04-01

The X-ray micro-calorimeter array in the Soft X-ray Spectrometer (SXS) instrument on Astro-H will be cooled by a 3-stage adiabatic demagnetization refrigerator (ADR). The ADR consists of two mechanically independent assemblies. When integrated with a mounting structure and the detector assembly, they form a self-contained unit that will be inserted into the top end of a liquid helium tank. The unique configuration requires many components and sub-assemblies to be thermally isolated from their structural mount. Normally in an ADR this is limited to suspending cold salt pills within their (much warmer) magnets, but in the case of SXS, it also involves one ADR stage being supported by, but thermally isolated from, the helium tank. This paper will describe the complex thermal and mechanical design of the SXS ADR, and summarize vibration and mechanical properties tests that have been performed to validate the design.
Performance of ASTRO-H Hard X-Ray Telescope (HXT)

NASA Technical Reports Server (NTRS)

Awaki, Hisamitsu; Kunieda, Hideyo; Ishida, Manabu; Matsumoto, Hironori; Furuzawa, Akihiro; Haba, Yohsito; Hayashi, Takayuki; Iizuka, Ryo; Ishibashi, Kazunori; Itoh, Masayuki;

2016-01-01

The Japanese X-ray Astronomy Satellite, Hitomi (ASTRO-H) carries hard X-ray imaging system, covering the energy band from 5 keV to 80 keV. The hard X-ray imaging system consists of two hard X-ray telescopes (HXT) and two hard X-ray imagers (HXI). The HXT employs tightly-nested, conically-approximated thin foil Wolter-I optics. The mirror surfaces of HXT were coated with PtC depth-graded multilayers. We carried out ground calibrations of HXTs at the synchrotron radiation facility SPring-8 BL20B2 in Japan, and found that total effective area of two HXTs was about 350 sq cm at 30 keV, and the half power diameter of HXT was about 1.9. After the launch of Hitomi, Hitomi observed several targets during the initial functional verification of the onboard instruments. The Hitomi software and calibration team (SCT) provided the Hitomis data of G21.5-0.9, a pulsar wind nebula, to the hardware team for the purpose of the instrument calibration. Through the analysis of the in-flight data, we have confirmed that the X-ray performance of HXTs in orbit was consistent with that estimated by the ground calibrations.

The Design, Implementation, and Performance of the Astro-H SXS Calorimeter Array and Anti-Coincidence Detector

NASA Technical Reports Server (NTRS)

Kilbourne, Caroline A.; Adams, Joseph S.; Brekosky, Regis P.; Chiao, Meng P.; Chervenak, James A.; Eckart, Megan E.; Figueroa-Feliciano, Enectali; Galeazzi, Masimilliano; Grein, Christoph; Jhabvala, Christine A.;

2016-01-01

The calorimeter array of the JAXA Astro-H (renamed Hitomi) Soft X-ray Spectrometer (SXS) was designed to provide unprecedented spectral resolution of spatially extended cosmic x-ray sources and of all cosmic x-ray sources in the Fe-K band around 6 keV, enabling essential plasma diagnostics. The SXS has a square array of 36 microcalorimeters at the focal plane. These calorimeters consist of ion-implanted silicon thermistors and HgTe thermalizing x-ray absorbers. These devices have demonstrated a resolution of better than 4.5 eV at 6 keV when operated at a heat-sink temperature of 50 mK. We will discuss the basic physical parameters of this array, including the array layout, thermal conductance of the link to the heat sink, resistance function, absorber details, and means of attaching the absorber to the thermistor-bearing element. We will also present the thermal characterization of the whole array, including thermal conductance and crosstalk measurements and the results of pulsing the frame temperature via alpha particles, heat pulses, and the environmental background. A silicon ionization detector is located behind the calorimeter array and serves to reject events due to cosmic rays. We will briefly describe this anti-coincidence detector and its performance.

Phase-resolved X-ray polarimetry of the Crab pulsar with the AstroSat CZT Imager

NASA Astrophysics Data System (ADS)

Vadawale, S. V.; Chattopadhyay, T.; Mithun, N. P. S.; Rao, A. R.; Bhattacharya, D.; Vibhute, A.; Bhalerao, V. B.; Dewangan, G. C.; Misra, R.; Paul, B.; Basu, A.; Joshi, B. C.; Sreekumar, S.; Samuel, E.; Priya, P.; Vinod, P.; Seetha, S.

2018-01-01

The Crab pulsar is a typical example of a young, rapidly spinning, strongly magnetized neutron star that generates broadband electromagnetic radiation by accelerating charged particles to near light speeds in its magnetosphere1. Details of this emission process so far remain poorly understood. Measurement of polarization in X-rays, particularly as a function of pulse phase, is thought to be a key element necessary to unravel the mystery of pulsar radiation2-4. Such measurements are extremely difficult, however: to date, Crab is the only pulsar to have been detected in polarized X-rays5-8 and the measurements have not been sensitive enough to adequately reveal the variation of polarization characteristics across the pulse7. Here, we present the most sensitive measurement to date of polarized hard X-ray emission from the Crab pulsar and nebula in the 100-380 keV band, using the Cadmium-Zinc-Telluride Imager9 instrument on-board the Indian astronomy satellite AstroSat10. We confirm with high significance the earlier indication6,7 of a strongly polarized off-pulse emission. However, we also find a variation in polarization properties within the off-pulse region. In addition, our data hint at a swing of the polarization angle across the pulse peaks. This behaviour cannot be fully explained by the existing theoretical models of high-energy emission from pulsars.
Ultra High Energy Cosmic Rays: Strangelets?

NASA Astrophysics Data System (ADS)

Xu, Ren-Xin; Wu, Fei

2003-06-01

The conjecture that ultra-high-energy cosmic rays (UHECRs) are actually strangelets is discussed. Besides the reason that strangelets can do as cosmic rays beyond the Greisen-Zatsepin-Kuzmin-cutoff, another argument to support the conjecture is addressed by the study of formation of TeV-scale microscopic black holes when UHECRs bombarding bare strange stars. It is proposed that the exotic quark surface of a bare strange star could be an effective astro-laboratory in the investigations of the extra dimensions and of the detection of ultra-high-energy neutrino fluxes. The flux of neutrinos (and other point-like particles) with energy larger than 2.3×1020 eV could be expected to be smaller than 10-26 cm-2 s-1 if there are two extra spatial dimensions.
Performance of the Fourier transform spectrometer (FTS) for FIS onboard ASTRO-F

NASA Astrophysics Data System (ADS)

Murakami, Noriko; Kawada, Mitsunobu; Takahashi, Hidenori; Ozawa, Keita; Imamura, Tetsuo; Shibai, Hiroshi; Nakagawa, Takao

2004-10-01

We have developed the imaging Fourier Transform Spectrometer (FTS) for the FIS (Far-Infrared Surveyor) onboard the ASTRO-F satellite. A Martin-Puplett interferometer is adopted to achieve high optical efficiency in a wide wavelength range. The total optical efficiency of this spectrometer is achieved 40-80% of the ideal value which is 25% of the incident flux. The wavelength range of 50-200μm is covered with two kinds of detector; the monolithic Ge:Ga photoconductor array for short wavelength (50-110μm) and the stressed Ge:Ga photoconductor array for long wavelength (110-200μm). The spectral resolution expected from the maximum optical path difference is 0.18cm-1. In order to evaluate the spectral resolution of the FTS, we measured absorption lines of H2O in atmosphere using the optics of the FTS with a bolometer at the room temperature. The measured line widths are consistent with the expected instrumental resolution of 0.18 cm-1. Some spectral measurements at the cryogenic temperature were carried out by using cold blackbody sources whose temperatures are controlled in a range from 20 to 50 K. The derived spectra considering with the spectral response of the system are consistent with expected ones. Spectroscopic observations with the FTS will provide a lot of astronomical information; SED of galaxies detected in the all sky survey and the physical diagnostics of the interstellar matter by using the excited atomic or molecular lines.
Noninvasive Synchrotron-Based X-ray Raman Scattering Discriminates Carbonaceous Compounds in Ancient and Historical Materials [ In situ synchrotron-based X-Ray Raman scattering discriminates carbonaceous compounds in ancient and historical materials

DOE PAGES

Gueriau, Pierre; Rueff, Jean -Pascal; Bernard, Sylvain; ...

2017-09-13

Carbon compounds are ubiquitous and occur in a diversity of chemical forms in many systems including ancient and historic materials ranging from cultural heritage to paleontology. Determining their speciation cannot only provide unique information on their origin but may also elucidate degradation processes. Synchrotron-based X-ray absorption near-edge structure (XANES) spectroscopy at the carbon K-edge (280–350 eV) is a very powerful method to probe carbon speciation. However, the short penetration depth of soft X-rays imposes stringent constraints on sample type, preparation, and analytical environment. A hard X-ray probe such as X-ray Raman scattering (XRS) can overcome many of these difficulties. Heremore » we report the use of XRS at ~6 keV incident energy to collect carbon K-edge XANES data and probe the speciation of organic carbon in several specimens relevant to cultural heritage and natural history. This methodology enables the measurement to be done in a nondestructive way, in air, and provides information that is not compromised by surface contamination by ensuring that the dominant signal contribution is from the bulk of the probed material. Using the backscattering geometry at large photon momentum transfer maximizes the XRS signal at the given X-ray energy and enhances nondipole contributions compared to conventional XANES, thereby augmenting the speciation sensitivity. The capabilities and limitations of the technique are discussed. As a result, we show that despite its small cross section, for a range of systems the XRS method can provide satisfactory signals at realistic experimental conditions. XRS constitutes a powerful complement to FT-IR, Raman, and conventional XANES spectroscopy, overcoming some of the limitations of these techniques.« less
Performance Testing of the Astro-H Flight Model 3-Stage ADR

NASA Technical Reports Server (NTRS)

Shirron, Peter J.; Kimball, Mark Oliver; DiPirro, Michael; Bialas, Tom G.

2014-01-01

The Soft X-ray Spectrometer (SXS) is one of four instruments that will be flown on the Japanese Astro-H satellite, planned for launch in late 2015early 2016. The SXS will perform imaging spectroscopy in the soft x-ray band using a 6x6 array of silicon micro calorimeters operated at 50 mK, cooled by an adiabatic demagnetization refrigerator (ADR). NASAGSFC is providing the detector array and ADR, and Sumitomo Heavy Industries, Inc. is providing the remainder of the cryogenic system (superfluid helium dewar (1.3 K), Stirling cryocoolers and a 4.5 K Joule-Thomson (JT) cryocooler). The ADR is unique in that it is designed to use both the liquid helium and the JT cryocooler as it heat sink. The flight detector and ADR assembly have successfully undergone vibration and performance testing at GSFC, and have now undergone initial performance testing with the flight dewar at Sumitomo Heavy Industries, Inc. in Japan. This presentation summarizes the performance of the flight ADR in both cryogen-based and cryogen-free operating modes.
Performance Testing of the Astro-H Flight Model 3-stage ADR

NASA Astrophysics Data System (ADS)

Shirron, Peter J.; Kimball, Mark O.; DiPirro, Michael J.; Bialas, Thomas G.

The Soft X-ray Spectrometer (SXS) is one of four instruments that will be flown on the Japanese Astro-H satellite, planned for launch in late 2015/early 2016. The SXS will perform imaging spectroscopy in the soft x-ray band using a 6x6 array of silicon microcalorimeters operated at 50 mK, cooled by an adiabatic demagnetization refrigerator (ADR). NASA/GSFC is providing the detector array and ADR, and Sumitomo Heavy Industries, Inc. is providing the remainder of the cryogenic system (superfluid helium dewar (<1.3 K), Stirling cryocoolers and a 4.5 K Joule-Thomson (JT) cryocooler). The ADR is unique in that it is designed to use both the liquid helium and the JT cryocooler as it heat sink. The flight detector and ADR assembly have successfully undergone vibration and performance testing at GSFC, and have now undergone initial performance testing with the flight dewar at Sumitomo Heavy Industries, Inc. in Japan. This paper summaries the performance of the flight ADR in both cryogen-based and cryogen-free operating modes.
An x ray scatter approach for non-destructive chemical analysis of low atomic numbered elements

NASA Technical Reports Server (NTRS)

Ross, H. Richard

1993-01-01

A non-destructive x-ray scatter (XRS) approach has been developed, along with a rapid atomic scatter algorithm for the detection and analysis of low atomic-numbered elements in solids, powders, and liquids. The present method of energy dispersive x-ray fluorescence spectroscopy (EDXRF) makes the analysis of light elements (i.e., less than sodium; less than 11) extremely difficult. Detection and measurement become progressively worse as atomic numbers become smaller, due to a competing process called 'Auger Emission', which reduces fluorescent intensity, coupled with the high mass absorption coefficients exhibited by low energy x-rays, the detection and determination of low atomic-numbered elements by x-ray spectrometry is limited. However, an indirect approach based on the intensity ratio of Compton and Rayleigh scattered has been used to define light element components in alloys, plastics and other materials. This XRS technique provides qualitative and quantitative information about the overall constituents of a variety of samples.
Validation of 64Cu-ATSM damaging DNA via high-LET Auger electron emission.

PubMed

McMillan, Dayton D; Maeda, Junko; Bell, Justin J; Genet, Matthew D; Phoonswadi, Garrett; Mann, Kelly A; Kraft, Susan L; Kitamura, Hisashi; Fujimori, Akira; Yoshii, Yukie; Furukawa, Takako; Fujibayashi, Yasuhisa; Kato, Takamitsu A

2015-09-01

Radioactive copper (II) (diacetyl-bis N4-methylthiosemicarbazone) (Cu-ATSM) isotopes were originally developed for the imaging of hypoxia in tumors. Because the decay of a (64)Cu atom is emitting not only positrons but also Auger electrons, this radionuclide has great potential as a theranostic agent. However, the success of (64)Cu-ATSM internal radiation therapy would depend on the contribution of Auger electrons to tumor cell killing. Therefore, we designed a cell culture system to define the contributions to cell death from Auger electrons to support or refute our hypothesis that the majority of cell death from (64)Cu-ATSM is a result of high-LET Auger electrons and not positrons or other low-LET radiation. Chinese hamster ovary (CHO) wild type and DNA repair-deficient xrs5 cells were exposed to (64)Cu-ATSM during hypoxic conditions. Surviving fractions were compared with those surviving gamma-radiation, low-LET hadron radiation, and high-LET heavy ion exposure. The ratio of the D(10) values (doses required to achieve 10% cell survival) between CHO wild type and xrs5 cells suggested that (64)Cu-ATSM toxicity is similar to that of high-LET Carbon ion radiation (70 keV/μm). γH2AX foci assays confirmed DNA double-strand breaks and cluster damage by high-LET Auger electrons from (64)Cu decay, and complex types of chromosomal aberrations typical of high-LET radiation were observed after (64)Cu-ATSM exposure. The majority of cell death was caused by high-LET radiation. This work provides strong evidence that (64)Cu-ATSM damages DNA via high-LET Auger electrons, supporting further study and consideration of (64)Cu-ATSM as a cancer treatment modality for hypoxic tumors. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.
Validation of 64Cu-ATSM damaging DNA via high-LET Auger electron emission

PubMed Central

McMillan, Dayton D.; Maeda, Junko; Bell, Justin J.; Genet, Matthew D.; Phoonswadi, Garrett; Mann, Kelly A.; Kraft, Susan L.; Kitamura, Hisashi; Fujimori, Akira; Yoshii, Yukie; Furukawa, Takako; Fujibayashi, Yasuhisa; Kato, Takamitsu A.

2015-01-01

Radioactive copper (II) (diacetyl-bis N4-methylthiosemicarbazone) (Cu-ATSM) isotopes were originally developed for the imaging of hypoxia in tumors. Because the decay of a 64Cu atom is emitting not only positrons but also Auger electrons, this radionuclide has great potential as a theranostic agent. However, the success of 64Cu-ATSM internal radiation therapy would depend on the contribution of Auger electrons to tumor cell killing. Therefore, we designed a cell culture system to define the contributions to cell death from Auger electrons to support or refute our hypothesis that the majority of cell death from 64Cu-ATSM is a result of high-LET Auger electrons and not positrons or other low-LET radiation. Chinese hamster ovary (CHO) wild type and DNA repair–deficient xrs5 cells were exposed to 64Cu-ATSM during hypoxic conditions. Surviving fractions were compared with those surviving gamma-radiation, low-LET hadron radiation, and high-LET heavy ion exposure. The ratio of the D10 values (doses required to achieve 10% cell survival) between CHO wild type and xrs5 cells suggested that 64Cu-ATSM toxicity is similar to that of high-LET Carbon ion radiation (70 keV/μm). γH2AX foci assays confirmed DNA double-strand breaks and cluster damage by high-LET Auger electrons from 64Cu decay, and complex types of chromosomal aberrations typical of high-LET radiation were observed after 64Cu-ATSM exposure. The majority of cell death was caused by high-LET radiation. This work provides strong evidence that 64Cu-ATSM damages DNA via high-LET Auger electrons, supporting further study and consideration of 64Cu-ATSM as a cancer treatment modality for hypoxic tumors. PMID:26251463
The AstroVR Collaboratory, an On-line Multi-User Environment for Research in Astrophysics

NASA Astrophysics Data System (ADS)

van Buren, D.; Curtis, P.; Nichols, D. A.; Brundage, M.

We describe our experiment with an on-line collaborative environment where users share the execution of programs and communicate via audio, video, and typed text. Collaborative environments represent the next step in computer-mediated conferencing, combining powerful compute engines, data persistence, shared applications, and teleconferencing tools. As proof of concept, we have implemented a shared image analysis tool, allowing geographically distinct users to analyze FITS images together. We anticipate that \\htmllink{AstroVR}{http://astrovr.ipac.caltech.edu:8888} and similar systems will become an important part of collaborative work in the next decade, including with applications in remote observing, spacecraft operations, on-line meetings, as well as and day-to-day research activities. The technology is generic and promises to find uses in business, medicine, government, and education.
Enhancing ASTRO101 Student Engagement Using Student-Created ScienceSKETCHES

NASA Astrophysics Data System (ADS)

Slater, Timothy F.; Slater, Stephanie

2016-01-01

As astronomy teaching faculty are changing their teaching strategies from those less desirable approaches that allow students to passively listen to professor-centered, information-lectures to more desirable, active-student engagement classrooms characterized by active learning, ASTRO 101 professors are looking for more ways to help students learn to participate in authentic scientific practices. This is consistent with notion advocated by the NRC that students should practice scientific thinking, scientific discourse, and scientific practices while learning science. Noticing that much informal scientific discussion is mediated by sketches—such as those occasionally lively discussions held after hours during scientific conferences—scholars at the CAPER Center for Astronomy & Physics Education Research have been piloting a series of active learning tasks where students are challenged to create scientific drawings to illustrate their understanding of astronomical phenomena or structures. Known informally as ScienceSKETCHES, examples of these tasks challenge students to illustrate: the spectral curve differences between high and low mass stars; the differences among galaxy shapes; the distribution of stars for the Andromeda Galaxy in terms of luminosity versus temperature; old and young planetary surfaces; or the relationships between distances and speeds of orbiting objects. Although our initial testing has focused on predominately on paper and pencil tasks, with the occasional cell phone picture of a ScienceSKETCH being texted to the professor, the electronic-based teaching world is nearly ready to support these sorts of drawing tasks. Already, the ability to complete and submit scientific sketches is becoming commonplace across electronic learning platforms, including shared white-boarding in many desktop videoconferencing systems, and handheld device learning systems for interactive classrooms, like those from Learning Catalytics, among many others. Our

Graeco-Roman Astro-Architecture: The Temples of Pompeii

NASA Astrophysics Data System (ADS)

Tiede, Vance R.

2014-01-01

Roman architect Marcus Vetruvius Pollio (ca. 75-15 BC) wrote, “[O]ne who professes himself as an architect should be…acquainted with astronomy and the theory of the heavens…. From astronomy we find the east, west, south, and north, as well as the theory of the heavens, the Equinox, Solstice and courses of the Stars.” (De Architectura Libri Decem I:i:3,10). In order to investigate the role of astronomy in temple orientation, the author conducted a preliminary GIS DEM/Satellite Imaging survey of 11 temples at Pompeii, Italy (N 40d 45', E 14d 29'). The GIS survey measured the true azimuth and horizon altitude of each temple’s major axis and was field checked by a Ground Truth survey with theodolite and GPS, 5-18 April 2013. The resulting 3D vector data was analyzed with Program STONEHENGE (Hawkins 1983, 328) to identify the local skyline declinations aligned with the temple major axes. Analysis suggests that the major axes of the temples of Apollo, Jupiter and Venus are equally as likely to have been oriented to Pompeii’s urban grid, itself oriented NW-SE on Mt. Vesuvius’ slope and hydraulic gradient to optimize urban sewer/street drainage (cf. Hodge 1992). However, the remaining nine temples appear to be oriented to astronomical targets on the local horizon associated with Graeco-Roman calendrics and mythology. TEMPLE/ DATE/ MAJOR AXIS ASTRO-TARGET (Skyline Declination in degrees) Public Lares/AD 50/ Cross-Quarter 7 Nov/3 Feb Sun Set, Last Gleam (-16.5) Vespsian/ AD 69-79/ Cross-Quarter 7 Nov/3 Feb Sun Set, LG (-16.2) Fortuna Augusta/ AD 1/ Winter Solstice Sun Set, LG (-22.9) Aesculapius/ 100 BC/ Perseus Rise (β Persei-Algol = +33.0) & Midsummer Moon Major Stand Still Set, LG (-28.1) Isis/ 100 BC/ Midwinter Moon Major Stand Still Rise, Tangent (+28.5) & Equinox Sun Set, Tangent (-0.3) Jupiter/ 150 BC/ Θ Scorpionis-Sargas Rise (-38.0) Apollo/ 550 (rebuilt 70 BC)/ α Columbae-Phact Rise (-37.1) Venus/ 150 BC (rebuilt 70 BC)/ α Columbae-Phact Rise (-37
Classes Azur Astro Espace International Hands-on Space Experience

NASA Astrophysics Data System (ADS)

Jung, P.

2002-01-01

Created in 1994 in the wake of the closure of the Space Camp of Patrick Baudry in Cannes, Classes Azur Astro Espace (AAE) provide a world's unique combination of space and astronomy courses, as given by active and retired professionals of two of the best space and astronomical facilities extant: Alcatel Space in Cannes and Observatoire de la Côte d'Azur (OCA) in Nice, Grasse and Caussols. Fifteen space modules, of 30 to 60 minutes each, have been established, giving simple and clear explanations on launchers, satellites, their applications, their development, together with an historical background. Basic experiments are included, such as an unique small catapult to explain gravity, or more classical water rockets. The basic AAE sojourn extends over 3 days: one day for space (including a visit of Alcatel Space, the biggest satellite manufacturer outside the US and Russia), one day for astronomy (including a visit of the biggest observatory in Europe) and one day à-la-carte (Côte d'Azur offers much, such as the Oceanographic Museum in Monaco). More and more groups are adding a fourth day, with a visit to the nice old village of Perinaldo in Italy, where famous astronomer Cassini was born. Lycée de Cachan, near Paris, even takes 12-day sojourns every year. The public has been extremely wide, from age 5 to 70, from students to enthusiasts. Coming initially all over from France, participants now include since 2001 German and Italian pupils and teachers. In 2001 also, ESA came in the shape of a Space Camp. ISU's Master of Space Studies participates to a shortened version of AAE every even-year. Up to the end of 2001, 62 classes with 2,025 participants from 20 countries had thus come to enjoy space education on Côte d'Azur. Such success is due in no small part to the very attractive price and flexibility of these activities, notably thanks to the support of ESA, CNES, Rectorat d'Académie de Nice, Conseil Général des Alpes-Maritimes, Ville de Cannes, AAAF, TDF
Teaching ASTRO 101 Students the Art of Scientific Argumentation

NASA Astrophysics Data System (ADS)

Schleigh, Sharon P.; Slater, Stephanie; Slater, Timothy F.

2016-01-01

Going beyond asking students to simply memorize facts about the universe, a longstanding challenge in teaching astronomy centers on successfully teaching students about the nature of science. As introductory astronomy survey courses, known widely as ASTRO 101, can sometimes be the last science course non-science majoring undergraduates take, many faculty hope to emphasize the scientific enterprise as a broad field in inquiry making valuable contributions to civilization as a whole, rather than as an isolated study of objects far from Earth. Scholars have long proposed that an understanding of the nature of science as a human endeavor requires explicit instruction. In other words, students successfully learning the facts of astronomy does not in any way ensure that students will learn anything about the nature of how astronomy is done. In a purposeful effort to improve students' understanding about the practices and discourse of astronomy, scholars working with the CAPER Center for Astronomy & Physics Education research are developing a suite of carefully designed instructional sequences—called Scientific Argumentation—focused on teaching students the differences between data and evidence, how to communicate and defend evidence-based conclusions, and how to be informed skeptics of scientific claims. Early results show students moving from naïve understandings of scientific practices to more informed understandings as well as demonstrating enhanced value for science in general as an worthwhile human endeavor with far reaching benefits.
Thermodynamic Analysis of the 3-Stage ADR for the Astro-H Soft X-Ray Spectrometer Instrument

NASA Technical Reports Server (NTRS)

Shirron, Peter; Kimball, Mark; DiPirro, Michael; Bialas, Tom; Sneiderman, Gary; Porter, Scott; Kelley, Richard

2015-01-01

The Soft X-ray Spectrometer (SXS) instrument on Astro-H will use a 3-stage ADR to cool the microcalorimeter array to 50 mK. In the primary operating mode, two stages of the ADR cool the detectors using superfluid helium at 1.20 K as the heat sink. In the secondary mode, which is activated when the liquid helium is depleted, two of the stages continuously cool the (empty) helium tank using a 4.5 K Joule-Thomson cooler as the heat sink, and the third stage cools the detectors. In the design phase, a high-fidelity model of the ADR was developed in order to predict both the cooling capacity and heat rejection rates in both operating modes. The primary sources of heat flow are from the salt pills, hysteresis heat from the magnets and magnetic shields, and power dissipated by the heat switches. The flight instrument dewar, ADR, detectors and electronics were integrated in mid-2014 and have since undergone extensive performance testing, in part to validate the performance model. This paper will present the thermodynamic performance of the ADR, including cooling capacity, heat rejection to the heat sinks, and various measures of efficiency.
High energy neutrinos from astrophysical accelerators of cosmic ray nuclei

NASA Astrophysics Data System (ADS)

Anchordoqui, Luis A.; Hooper, Dan; Sarkar, Subir; Taylor, Andrew M.

2008-02-01

Ongoing experimental efforts to detect cosmic sources of high energy neutrinos are guided by the expectation that astrophysical accelerators of cosmic ray protons would also generate neutrinos through interactions with ambient matter and/or photons. However, there will be a reduction in the predicted neutrino flux if cosmic ray sources accelerate not only protons but also significant numbers of heavier nuclei, as is indicated by recent air shower data. We consider plausible extragalactic sources such as active galactic nuclei, gamma ray bursts and starburst galaxies and demand consistency with the observed cosmic ray composition and energy spectrum at Earth after allowing for propagation through intergalactic radiation fields. This allows us to calculate the expected neutrino fluxes from the sources, normalized to the observed cosmic ray spectrum. We find that the likely signals are still within reach of next generation neutrino telescopes such as IceCube.PACS95.85.Ry98.70.Rz98.54.Cm98.54.EpReferencesFor a review, see:F.HalzenD.HooperRep. Prog. Phys.6520021025A.AchterbergIceCube CollaborationPhys. Rev. Lett.972006221101A.AchterbergIceCube CollaborationAstropart. Phys.262006282arXiv:astro-ph/0611063arXiv:astro-ph/0702265V.NiessANTARES CollaborationAIP Conf. Proc.8672006217I.KravchenkoPhys. Rev. D732006082002S.W.BarwickANITA CollaborationPhys. Rev. Lett.962006171101V.Van ElewyckPierre Auger CollaborationAIP Conf. Proc.8092006187For a survey of possible sources and event rates in km3 detectors see e.g.,W.BednarekG.F.BurgioT.MontaruliNew Astron. Rev.4920051M.D.KistlerJ.F.BeacomPhys. Rev. D742006063007A. Kappes, J. Hinton, C. Stegmann, F.A. Aharonian, arXiv:astro-ph/0607286.A.LevinsonE.WaxmanPhys. Rev. Lett.872001171101C.DistefanoD.GuettaE.WaxmanA.LevinsonAstrophys. J.5752002378F.A.AharonianL.A.AnchordoquiD.KhangulyanT.MontaruliJ. Phys. Conf. Ser.392006408J.Alvarez-MunizF.HalzenAstrophys. J.5762002L33F.VissaniAstropart. Phys.262006310F
Examining the Angular Resolution of the Astro-H's Soft X-Ray Telescopes

NASA Technical Reports Server (NTRS)

Sato, Toshiki; Iizuka, Ryo; Ishida, Manabu; Kikuchi, Naomichi; Maeda, Yoshitomo; Kurashima, Sho; Nakaniwa, Nozomi; Tomikawa, Kazuki; Hayashi, Takayuki; Mori, Hideyuki;

2016-01-01

The international x-ray observatory ASTRO-H was renamed Hitomi after launch. It covers a wide energy range from a few hundred eV to 600 keV. It is equipped with two soft x-ray telescopes (SXTs: SXT-I and SXT-S) for imaging the soft x-ray sky up to 12 keV, which focus an image onto the respective focal-plane detectors: CCD camera (SXI) and a calorimeter (SXS). The SXTs are fabricated in a quadrant unit. The angular resolution in half-power diameter (HPD) of each quadrant of the SXTs ranges between 1.1 and 1.4 arc min at 4.51 keV. It was also found that one quadrant has an energy dependence on the HPD. We examine the angular resolution with spot scan measurements. In order to understand the cause of imaging capability deterioration and to reflect it to the future telescope development, we carried out spot scan measurements, in which we illuminate all over the aperture of each quadrant with a square beam 8 mm on a side. Based on the scan results, we made maps of image blurring and a focus position. The former and the latter reflect figure error and positioning error, respectively, of the foils that are within the incident 8 mm x 8 mm beam. As a result, we estimated those errors in a quadrant to be approx. 0.9 to 1.0 and approx. 0.6 to 0.9 arc min, respectively. We found that the larger the positioning error in a quadrant is, the larger its HPD is. The HPD map, which manifests the local image blurring, is very similar from quadrant to quadrant, but the map of the focus position is different from location to location in each telescope. It is also found that the difference in local performance causes energy dependence of the HPD.

Development of a Silicon Drift Detector Array: An X-Ray Fluorescence Spectrometer for Remote Surface Mapping

NASA Technical Reports Server (NTRS)

Gaskin, Jessica A.; Carini, Gabriella A.; Wei, Chen; Elsner, Ronald F.; Kramer, Georgiana; De Geronimo, Gianluigi; Keister, Jeffrey W.; Zheng, Li; Ramsey, Brian D.; Rehak, Pavel;

2009-01-01

Over the past three years NASA Marshall Space Flight Center has been collaborating with Brookhaven National Laboratory to develop a modular Silicon Drift Detector (SDD) X-Ray Spectrometer (XRS) intended for fine surface mapping of the light elements of the moon. The value of fluorescence spectrometry for surface element mapping is underlined by the fact that the technique has recently been employed by three lunar orbiter missions; Kaguya, Chandrayaan-1, and Chang e. The SDD-XRS instrument we have been developing can operate at a low energy threshold (i.e. is capable of detecting Carbon), comparable energy resolution to Kaguya (<150 eV at 5.9 keV) and an order of magnitude lower power requirement, making much higher sensitivities possible. Furthermore, the intrinsic radiation resistance of the SDD makes it useful even in radiation-harsh environments such as that of Jupiter and its surrounding moons.

The Soft X-ray Imager (SXI) for the ASTRO-H Mission

NASA Astrophysics Data System (ADS)

Tanaka, Takaaki; Tsunemi, Hiroshi; Hayashida, Kiyoshi; Tsuru, Takeshi G.; Dotani, Tadayasu; Nakajima, Hiroshi; Anabuki, Naohisa; Nagino, Ryo; Uchida, Hiroyuki; Nobukawa, Masayoshi; Ozaki, Masanobu; Natsukari, Chikara; Tomida, Hiroshi; Ueda, Shutaro; Kimura, Masashi; Hiraga, Junko S.; Kohmura, Takayoshi; Murakami, Hiroshi; Mori, Koji; Yamauchi, Makoto; Hatsukade, Isamu; Nishioka, Yusuke; Bamba, Aya; Doty, John P.

2015-09-01

The Soft X-ray Imager (SXI) is an X-ray CCD camera onboard the ASTRO-H X-ray observatory. The CCD chip used is a P-channel back-illuminated type, and has a 200-µm thick depletion layer, with which the SXI covers the energy range between 0.4 keV and 12 keV. Its imaging area has a size of 31 mm x 31 mm. We arrange four of the CCD chips in a 2 by 2 grid so that we can cover a large field-of-view of 38' x 38'. We cool the CCDs to -120 °C with a single-stage Stirling cooler. As was done for the CCD camera of the Suzaku satellite, XIS, artificial charges are injected to selected rows in order to recover charge transfer inefficiency due to radiation damage caused by in-orbit cosmic rays. We completed fabrication of flight models of the SXI and installed them into the satellite. We verified the performance of the SXI in a series of satellite tests. On-ground calibrations were also carried out and detailed studies are ongoing.
Catholic University Co-Operative Agreement

NASA Technical Reports Server (NTRS)

Werntz, Carl; Starr, Richard

1998-01-01

R. Starr is the leader of the science team for the X-Ray Spectrometer (XRS) which will fly on-board the SSTI Clark satellite. This XRS will fly small room-temperature, solid-state detectors that have never been flown in space before. In addition to testing this new technology, this instrument is designed to detect X-rays from solar flares and gamma-ray bursts in the energy region from about 1 keV to 100 keV. The XRS has been through environmental testing and has been integrated to the spacecraft. The Clark spacecraft is scheduled to be launched in August 1998 and the XRS will collect data in orbit continuously for the next three years.
In-flight performance of pulse-processing system of the ASTRO-H/Hitomi soft x-ray spectrometer

NASA Astrophysics Data System (ADS)

Ishisaki, Yoshitaka; Yamada, Shinya; Seta, Hiromi; Tashiro, Makoto S.; Takeda, Sawako; Terada, Yukikatsu; Kato, Yuka; Tsujimoto, Masahiro; Koyama, Shu; Mitsuda, Kazuhisa; Sawada, Makoto; Boyce, Kevin R.; Chiao, Meng P.; Watanabe, Tomomi; Leutenegger, Maurice A.; Eckart, Megan E.; Porter, Frederick Scott; Kilbourne, Caroline Anne

2018-01-01

We summarize results of the initial in-orbit performance of the pulse shape processor (PSP) of the soft x-ray spectrometer instrument onboard ASTRO-H (Hitomi). Event formats, kind of telemetry, and the pulse-processing parameters are described, and the parameter settings in orbit are listed. The PSP was powered-on 2 days after launch, and the event threshold was lowered in orbit. The PSP worked fine in orbit, and there was neither memory error nor SpaceWire communication error until the break-up of spacecraft. Time assignment, electrical crosstalk, and the event screening criteria are studied. It is confirmed that the event processing rate at 100% central processing unit load is ˜200 c / s / array, compliant with the requirement on the PSP.
The X-ray Spectrometer - A cryogenic instrument on the Advanced X-ray Astrophysics Facility

NASA Technical Reports Server (NTRS)

Breon, Susan R.; Hopkins, Richard A.; Nieczkoski, Stephen J.

1991-01-01

The X-ray Spectrometer (XRS) is an instrument on the Advanced X-ray Astrophysics Facility (AXAF), the third of NASA's Great Observatories scheduled for launch in 1998. The XRS detectors have a resolution of approximately 10 eV over the range 0.3 - 10 keV. To achieve this resolution, the detectors are maintained at or below 0.1 Kelvin using an adiabatic demagnetization refrigerator inside a superfluid helium dewar. In addition, split-Stirling-cycle mechanical coolers are used to extend the anticipated on-orbit helium lifetime to a minimum of 4 years. This paper describes the challenges of developing this hybrid cryogenic system and presents an overview of the current design of the system.
Vibration Isolation System for Cryocoolers of Soft X-Ray Spectrometer (SXS) Onboard ASTRO-H (Hitomi)

NASA Technical Reports Server (NTRS)

Takei, Yoh; Yasuda, Susumu; Ishimura, Kosei; Iwata, Naoko; Okamoto, Atsushi; Sato, Yoichi; Ogawa, Mina; Sawada, Makoto; Kawano, Taro; Obara, Shingo;

2016-01-01

Soft X-ray Spectrometer (SXS) onboard ASTRO-H (named Hitomi after launch) is a micro-calorimeter-type spectrometer, installed in a dewar to be cooled at 50 mK. The energy resolution of the SXS engineering model suffered from micro-vibration from cryocoolers mounted on the dewar. This is mitigated for the flight model by introducing vibration isolation systems between the cryocoolers and the dewar. The detector performance of the flight model was verified before launch of the spacecraft in both ambient condition and thermal-vac condition, showing no detectable degradation in energy resolution. The in-orbit performance was also consistent with that on ground, indicating that the cryocoolers were not damaged by launch environment. The design and performance of the vibration isolation system along with the mechanism of how the micro-vibration could degrade the cryogenic detector is shown.

[Intragenic mitotic recombination induced by ultraviolet and gamma rays in radiosensitive mutants of Saccharomyces cerevisiae yeasts].

PubMed

Zakharov, I A; Kasinova, G V; Koval'tsova, S V

1983-01-01

The effect of UV- and gamma-irradiation on the survival and intragenic mitotic recombination (gene conversion) of 5 radiosensitive mutants was studied in comparison with the wild type. The level of spontaneous conversion was similar for RAD, rad2 and rad15, mutations xrs2 and xrs4 increasing and rad54 significantly decreasing it. The frequency of conversion induced by UV-light was greater in rad2, rad15 and xrs2 mutants and lower in xrs4, as compared to RAD. Gamma-irradiation caused induction of gene conversion with an equal frequency in RAD, rad2, rad15. Xrs2 and xrs4 mutations slightly decreased gamma-induced conversion. In rad54 mutant, UV-and gamma-induced conversion was practically absent. In the wild type yeast, a diploid strain is more resistant than a haploid, whereas in rad54 a diploid strain has the same or an increased sensitivity, as compared to a haploid strain (the "inverse ploidy effect"). This effect and also the block of induced mitotic recombination caused by rad54 indicate the presence in the yeast Saccharomyces cerevisiae of repair pathways of UV- and gamma-induced damages acting in diploid cells and realised by recombination. The data obtained as a result of many years' investigation of genetic effects in radiosensitive mutants of yeast are summarised and considered.
Performance of the EBIT calorimeter spectrometer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Porter, Frederick Scott; Gygax, John; Kelley, Richard L.

The EBIT calorimeter spectrometer (ECS) is a new high-resolution, broadband x-ray spectrometer that has recently been installed at the Electron Beam Ion Trap Facility (EBIT) at the Lawrence Livermore National Laboratory. The ECS is an entirely new production class spectrometer that replaces the XRS/EBIT spectrometer that has been operating at EBIT since 2000. The ECS utilizes a 32-pixel x-ray calorimeter array from the XRS instrument on the Suzaku x-ray observatory. Eighteen of the pixels are optimized for the 0.1-10 keV band and yield 4.5 eV full width at half maximum energy resolution and 95% quantum efficiency at 6 keV. Inmore » addition, the ECS includes 14 detector pixels that are optimized for the high-energy band with a bandpass from 0.5 to over 100 keV with 34 eV resolution and 32% quantum efficiency at 60 keV. The ECS detector array is operated at 50 mK using a five stage cryogenic system that is entirely automated. The instrument takes data continuously for over 65 h with a 2.5 h recycle time. The ECS is a nondispersive, broadband, highly efficient spectrometer that is one of the prime instruments at the EBIT facility. The instrument is used for studies of absolute cross sections, charge exchange recombination, and x-ray emission from nonequilibrium plasmas, among other measurements in our laboratory astrophysics program.« less
Identifying Organic Molecules in Space: The AstroBiology Explorer (ABE) Mission Concept

NASA Technical Reports Server (NTRS)

Ennico, Kimberly; Sandford, S.; Allamandola, L.; Bregman, J.; Cohen, M.; Cruikshank, D.; Dumas, C.; Greene, T.; Hudgins, D.; Kwok, S.

2004-01-01

The AstroBiology Explorer (ABE) mission concept consists of a modest dedicated space observatory having a 60 cm class primary mirror cooled to T less than 50 K equipped with medium resolution cross-dispersed spectrometers having cooled large format near- and mid-infrared detector arrays. Such a system would be capable of addressing outstanding problems in Astrochemistry and Astrophysics that are particularly relevant to Astrobiology and addressable via astronomical observation. The mission's observaticxiai program woiild make fundamental scieztific: prngress in establishing the nature, distribution, formation and evolution of organic and other molecular materials in the following extra-terrestrial environments: 1) The Outflow of Dying Stars; 2) The Diffuse Interstellar Medium (DISM); 3) Dense Molecular Clouds, Star Formation Regions, and Young Stellar/Planetary Systems; 4) Planets, Satellites, and Small Bodies within the Solar System; and 5) The Interstellar Media of Other Galaxies ABE could make fundamental progress in all of these area by conducting a 1 to 2 year mission to obtain a coordinated set of infrared spectroscopic observations over the 2.5 - 20 micron spectral range at a spectral resolution of R greater than 2500 of about 1500 galaxies, stars, planetary nebulae, young stellar objects, and solar system objects.
Deconvolving instrumental and intrinsic broadening in core-shell x-ray spectroscopies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fister, T. T.; Seidler, G. T.; Rehr, J. J.

2007-05-01

Intrinsic and experimental mechanisms frequently lead to broadening of spectral features in core-shell spectroscopies. For example, intrinsic broadening occurs in x-ray absorption spectroscopy (XAS) measurements of heavy elements where the core-hole lifetime is very short. On the other hand, nonresonant x-ray Raman scattering (XRS) and other energy loss measurements are more limited by instrumental resolution. Here, we demonstrate that the Richardson-Lucy (RL) iterative algorithm provides a robust method for deconvolving instrumental and intrinsic resolutions from typical XAS and XRS data. For the K-edge XAS of Ag, we find nearly complete removal of {approx}9.3 eV full width at half maximum broadeningmore » from the combined effects of the short core-hole lifetime and instrumental resolution. We are also able to remove nearly all instrumental broadening in an XRS measurement of diamond, with the resulting improved spectrum comparing favorably with prior soft x-ray XAS measurements. We present a practical methodology for implementing the RL algorithm in these problems, emphasizing the importance of testing for stability of the deconvolution process against noise amplification, perturbations in the initial spectra, and uncertainties in the core-hole lifetime.« less
Measuring the Heat Load on the Flight ASTRO-H Soft Xray Spectrometer Dewar

NASA Technical Reports Server (NTRS)

DiPirro, M.; Shirron, P.; Yoshida, S.; Kanao, K.; Tsunematsu, S.; Fujimoto, R.; Sneiderman, G.; Kimball, M.; Ezoe, Y.; Ishikawa, K.;

2015-01-01

The Soft Xray Spectrometer (SXS) instrument on-board the ASTRO-H X-ray mission is based on microcalorimeters operating at 50 mK. Low temperature is achieved by use of an adiabatic demagnetization refrigerator (ADR) cyclically operating up to a heat sink at either 1.2 K or 4.5 K. The 1.2 K heat sink is provided by a 40 liter superfluid helium dewar. The parasitic heat to the helium from supports, plumbing, wires, and radiation, and the cyclic heat dumped by the ADR operation determine the liquid helium lifetime. To measure this lifetime we have used various techniques to rapidly achieve thermal equilibrium and then measure the boil-off rate of the helium. We have measured a parasitic heat of 650 microwatts and a cyclic heat of 100 microwatts for a total of 750 microwatts. This closely matches the predicted heat load. Starting with a fill level at launch of more than 33 liters results in a lifetime of greater than 4 years for the liquid helium. The techniques and accuracy for this measurement will be explained in this paper.

Progress Toward a Compact 0.05 K Magnet Refrigerator Operating from 10 K

NASA Technical Reports Server (NTRS)

Canavan, Edgar; Shirron, Peter; DiPirro, Micheal; Tuttle, James; Jackson, Michael; King, Todd; Numazawa, Takenori

2003-01-01

Much of the most interesting information regarding our universe is hidden in the sub-millimeter, infrared, and x-rays bands of the spectrum, to which our atmosphere is largely opaque. Thus, missions exploring these bands are a very important part of NASA s Space Science program. Coincidentally, the most sensitive detectors in these spectral regions operate at extremely low temperatures, typically 0.05 - 0.10 K. Generally these temperatures will be achieved using magnetic refrigerators, also know as Adiabatic Demagnetization Refrigerators, or ADRs. Current ADRs, such as the one used in the XRS-II instrument on the Astro-E2 satellite, use a single-stage to cool detectors from 1.3 K to 0.06 K. The ADR is designed so that it can absorb the heat on the detector stage for at least 24 hours before it must stop, warm up to the helium bath temperature (1.3 K), and dump the accumulated heat. Future detector arrays will be much larger and will have higher heat dissipation. Furthermore, future missions will use mechanical cryocoolers to provide upper stage cooling, but they can only reach 4 - 10 K. Trying to scale heavy (-15 kg) single stage ADRs up to the higher heat loads and higher heat rejection temperatures required leads to unacceptably large systems. The GSFC Cryogenics Branch has developed the Continuous ADR (CADR) to solve this problem. The CADR consists of a series of ADR stages that sequentially pass heat from the load up to the high temperature heat sink. The stage connected to the load remains at a constant temperature. The continuous stage effectively decouples detector operation from ADR operation, allowing the ADR stages to be cycled much more rapidly. Rapid cycling leads to higher cooling power density. The cascading, multistage arrangement allows the magnetic refrigerant of each stage to be optimized for its own temperature swing. In the past year, we have made good progress toward a 0.05 to 10K system. A four-stage system that operates from 4.2 K was
Porous plug phase separator and superfluid film flow suppression system for the soft x-ray spectrometer onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Ezoe, Yuichiro; Ishikawa, Kumi; Mitsuishi, Ikuyuki; Ohashi, Takaya; Mitsuda, Kazuhisa; Fujimoto, Ryuichi; Murakami, Masahide; Kanao, Kenichi; Yoshida, Seiji; Tsunematsu, Shoji; DiPirro, Michael; Shirron, Peter

2016-07-01

Suppression of super fluid helium flow is critical for the Soft X-ray Spectrometer onboard ASTRO-H (Hitomi). In nominal operation, a small helium gas flow of 30 μg/s must be safely vented and a super fluid film flow must be sufficiently small <2 μg/s. To achieve a life time of the liquid helium, a porous plug phase separator and a film flow suppression system composed of an orifice, a heat exchanger, and knife edge devices are employed. In this paper, design, on-ground testing results and in-orbit performance of the porous plug and the film flow suppression system are described.
Cryogen free cooling of ASTRO-H SXS Helium Dewar from 300 K to 4 K

NASA Astrophysics Data System (ADS)

Kanao, Ken'ichi; Yoshida, Seiji; Miyaoka, Mikio; Tsunematsu, Shoji; Otsuka, Kiyomi; Hoshika, Shunji; Narasaki, Katsuhiro; Mitsuda, Kazuhisa; Yamasaki, Noriko; Takei, Yoh; Fujimoto, Ryuji; Sato, Yoichi; Okamoto, Atsushi; Noda, Hirofumi; DiPirro, Michel J.; Shirron, Peter J.

2017-12-01

Soft X-ray Spectrometer instrument (SXS) is one of the primary scientific instruments of ASTRO-H. SXS has a cold detector that is cooled to 50 mK by using a multi-stage Adiabatic Demagnetization Refrigerator (ADR). SXS Dewar containing ADR provides 1.3 K heat sink by using liquid helium in nominal operation. After liquid helium is dried up, 4 K heat sink is provided by using mechanical coolers. Both nominal operation and cryogen free operation were successfully demonstrated. This paper describes the test result of cryogen free operation and cool-down performance from room temperature by using only mechanical coolers without liquid helium. The coolers on the Dewar cooled down cold mass from around 300 K to 4 K with 260 W electric power in 40 days. Cold mass is 35 kg in 4 K area including the helium tank, ADR and detector assembly.

From truck to optical fibre: the coming-of-age of eVLBI

NASA Astrophysics Data System (ADS)

Szomoru, A.; Biggs, A.; Garrett, M.; van Langevelde, H. J.; Olnon, F.; Paragi, Z.; Parsley, S.; Pogrebenko, S.; Reynolds, C.

Spurred by the advent of disk-based recording systems and the nearly explosive increase of internet bandwidth, eVLBI (Parsley et al. te{parsley}) has undergone a remarkable development over the past two years. From ftp-based transfers of small amounts of astronomical data, through near real-time correlation (disk-buffered at the correlator), it has culminated this spring in the first three telescope real-time correlation at JIVE (Onsala, Westerbork and Jodrell Bank). In this paper we will give a review of this development and the current state of affairs. We will also address the current limitations and the way we may improve both bandwidth and reliability and finally we will discuss the opportunities a true high-bandwidth real-time VLBI correlator will provide. (astro-ph/0412686)
e-Infrastructures for Astronomy: An Integrated View

NASA Astrophysics Data System (ADS)

Pasian, F.; Longo, G.

2010-12-01

As for other disciplines, the capability of performing “Big Science” in astrophysics requires the availability of large facilities. In the field of ICT, computational resources (e.g. HPC) are important, but are far from being enough for the community: as a matter of fact, the whole set of e-infrastructures (network, computing nodes, data repositories, applications) need to work in an interoperable way. This implies the development of common (or at least compatible) user interfaces to computing resources, transparent access to observations and numerical simulations through the Virtual Observatory, integrated data processing pipelines, data mining and semantic web applications. Achieving this interoperability goal is a must to build a real “Knowledge Infrastructure” in the astrophysical domain. Also, the emergence of new professional profiles (e.g. the “astro-informatician”) is necessary to allow defining and implementing properly this conceptual schema.
A Mechanism of Intracellular P2X Receptor Activation*

PubMed Central

Sivaramakrishnan, Venketesh; Fountain, Samuel J.

2012-01-01

P2X receptors (P2XRs) are ATP-activated calcium-permeable ligand-gated ion channels traditionally viewed as sensors of extracellular ATP during diverse physiological processes including pain, inflammation, and taste. However, in addition to a cell surface residency P2XRs also populate the membranes of intracellular compartments, including mammalian lysosomes, phagosomes, and the contractile vacuole (CV) of the amoeba Dictyostelium. The function of intracellular P2XRs is unclear and represents a major gap in our understanding of ATP signaling. Here, we exploit the genetic versatility of Dictyostelium to investigate the effects of physiological concentrations of ATP on calcium signaling in isolated CVs. Within the CV, an acidic calcium store, P2XRs are orientated to sense luminal ATP. Application of ATP to isolated vacuoles leads to luminal translocation of ATP and release of calcium. Mechanisms of luminal ATP translocation and ATP-evoked calcium release share common pharmacology, suggesting that they are linked processes. The ability of ATP to mobilize stored calcium is reduced in vacuoles isolated from P2XAR knock-out amoeba and ablated in cells devoid of P2XRs. Pharmacological inhibition of luminal ATP translocation or depletion of CV calcium attenuates CV function in vivo, manifesting as a loss of regulatory cell volume decrease following osmotic swelling. We propose that intracellular P2XRs regulate vacuole activity by acting as calcium release channels, activated by translocation of ATP into the vacuole lumen. PMID:22736763
Thermodynamic Performance of the 3-Stage ADR for the Astro-H Soft X-Ray Spectrometer Instrument

NASA Technical Reports Server (NTRS)

Shirron, Peter J.; Kimball, Mark O.; James, Bryan L.; Muench, Theodore; DiPirro, Michael J.; Bialas, Thomas G.; Sneiderman, Gary A.; Porter, Frederick S.; Kelley, Richard L.

2015-01-01

The Soft X-ray Spectrometer (SXS) instrument[1] on Astro-H[2] will use a 3-stage ADR[3] to cool the microcalorimeter array to 50 mK. In the primary operating mode, two stages of the ADR cool the detectors using superfluid helium at =1.20 K as the heat sink[4]. In the secondary mode, which is activated when the liquid helium is depleted, the ADR uses a 4.5 K Joule-Thomson cooler as its heat sink. In this mode, all three stages operate together to continuously cool the (empty) helium tank and singleshot cool the detectors. The flight instrument - dewar, ADR, detectors and electronics - were integrated in 2014 and have since undergone extensive performance testing. This paper presents a thermodynamic analysis of the ADR's operation, including cooling capacity, heat rejection to the heat sinks, and various measures of efficiency.
Laboratory simulation of charge exchange-produced X-ray emission from comets.

PubMed

Beiersdorfer, P; Boyce, K R; Brown, G V; Chen, H; Kahn, S M; Kelley, R L; May, M; Olson, R E; Porter, F S; Stahle, C K; Tillotson, W A

2003-06-06

In laboratory experiments using the engineering spare microcalorimeter detector from the ASTRO-E satellite mission, we recorded the x-ray emission of highly charged ions of carbon, nitrogen, and oxygen, which simulates charge exchange reactions between heavy ions in the solar wind and neutral gases in cometary comae. The spectra are complex and do not readily match predictions. We developed a charge exchange emission model that successfully reproduces the soft x-ray spectrum of comet Linear C/1999 S4, observed with the Chandra X-ray Observatory.
Showing Some Chemistry

NASA Image and Video Library

2015-04-16

During NASA MESSENGER four-year orbital mission, the spacecraft X-Ray Spectrometer XRS instrument mapped out the chemical composition of Mercury and discovered striking regions of chemical diversity. These maps of magnesium/silicon (left) and aluminium/silicon (right) use red colors to indicate high values and blue colors for low values. In the maps shown here, the Caloris basin can be identified as a region with low Mg/Si and high Ca/Si on the upper left of each map. An extensive region with high Mg/Si is also clearly visible in the maps but is not correlated with any visible impact basin. Instrument: X-Ray Spectrometer (XRS) and Mercury Dual Imaging System (MDIS) Left Image: Map of Mg/Si Right Image: Map of Al/Si http://photojournal.jpl.nasa.gov/catalog/PIA19417
Inspiring a future generation of Astronomer and Astrophysicists during the 48th and 49th annual Astro-Science Workshop

NASA Astrophysics Data System (ADS)

Martynowycz, Michael; Ratliff, G.; Gyuk, G.; Hammergren, M.

2014-01-01

Aging of the technological workforce and declining STEM interest among teens gives impetus to a more exciting, hands-on approach to science education. As one of the longest running astronomy & astrophysics programs for high school students in the country, the Adler Planetarium’s Astro-Science Workshop (ASW) has continually evolved to best serve the out-of-school time needs of science-interested teens in the region. More than a decade ago, ASW underwent a major shift in underlying philosophy from a traditional lecture-oriented program to one focused on hands-on, student led inquiry in which students design, build, and conduct their own experiments. This strategy capitalizes on the natural inclinations of curious youth, and has found a strong synergy with the emerging “maker” movement. Over the past two years, a very successful effort has been made to retain students following ASW as volunteers in the Adler’s Far Horizons high-altitude ballooning group. The necessity to continually inspire and spark interests in science futures in our youth has been ongoing; this intense program serves this niche while giving students experiences they will keep with them for their entire lives. Here, we share our successes, failures, and future perspectives on astronomy education and the mission of widening the future pipeline of young scientists in the nation.
Recovering Residual Xenon Propellant for an Ion Propulsion System

NASA Technical Reports Server (NTRS)

Ganapathi, Gani; Skakkottai, P.; wu, Jiunn Jeng

2006-01-01

Future nuclear-powered Ion-Propulsion- System-propelled spacecraft such as Jupiter Icy Moon Orbiter (JIMO) will carry more than 10,000 kg of xenon propellant. Typically, a small percentage of this propellant cannot be used towards the end of the mission because of the pressure drop requirements for maintaining flow. For large missions such as JIMO, this could easily translate to over 250 kg of unusable xenon. A proposed system, the Xenon Recovery System (XRS), for recovering almost all of the xenon remaining in the tank, would include a cryopump in the form of a condenser/evaporator that would be alternatively cooled by a radiator, then heated electrically. When the pressure of the xenon in the tank falls below 0.7 MPa (100 psia), the previously isolated XRS will be brought online and the gas from the tank would enter the cryopump that is initially cooled to a temperature below saturation temperature of xenon. This causes xenon liquefaction and further cryopumping from the tank till the cryopump is full of liquid xenon. At this point, the cryopump is heated electrically by small heaters (70 to 80 W) to evaporate the liquid that is collected as high-pressure gas (<7 MPa; 1,000 psia) in an intermediate accumulator. Check valves between the tank and the XRS prevent the reverse flow of xenon during the heating cycle. The accumulator serves as the high-pressure source of xenon gas to the Xenon Feed System (XFS) downstream of the XRS. This cycle is repeated till almost all the xenon is recovered. Currently, this system is being baselined for JIMO.
Calibration of the Large Area X-Ray Proportional Counter (LAXPC) Instrument on board AstroSat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Antia, H. M.; Yadav, J. S.; Chauhan, Jai Verdhan

We present the calibration and background model for the Large Area X-ray Proportional Counter (LAXPC) detectors on board AstroSat . The LAXPC instrument has three nominally identical detectors to achieve a large collecting area. These detectors are independent of each other, and in the event analysis mode they record the arrival time and energy of each photon that is detected. The detectors have a time resolution of 10 μ s and a dead-time of about 42 μ s. This makes LAXPC ideal for timing studies. The energy resolution and peak channel-to-energy mapping were obtained from calibration on the ground usingmore » radioactive sources coupled with GEANT4 simulations of the detectors. The response matrix was further refined from observations of the Crab after launch. At around 20 keV the energy resolution of the detectors is 10%–15%, while the combined effective area of the three detectors is about 6000 cm{sup 2}.« less
Vibration isolation system for cryocoolers of soft x-ray spectrometer on-board ASTRO-H (Hitomi)

NASA Astrophysics Data System (ADS)

Takei, Yoh; Yasuda, Susumu; Ishimura, Kosei; Iwata, Naoko; Okamoto, Atsushi; Sato, Yoichi; Ogawa, Mina; Sawada, Makoto; Kawano, Taro; Obara, Shingo; Natsukari, Chikara; Wada, Atsushi; Yamada, Shinya; Fujimoto, Ryuichi; Kokubun, Motohide; Yamasaki, Noriko Y.; Sugita, Hiroyuki; Minesugi, Kenji; Nakamura, Yasuo; Mitsuda, Kazuhisa; Takahashi, Tadayuki; Yoshida, Seiji; Tsunematsu, Shoji; Kanao, Kenichi; Narasaki, Katsuhiro; Otsuka, Kiyomi; Scott Porter, F.; Kilbourne, Caroline A.; Chiao, Meng P.; Eckart, Megan E.; Sneiderman, Gary A.; Pontius, James T.; McCammon, Dan; Wilke, Paul; Basile, John

2018-01-01

The soft x-ray spectrometer (SXS) onboard ASTRO-H (named Hitomi after launch) is a microcalorimeter-type spectrometer, installed in a dewar to be cooled at 50 mK. The energy resolution of the SXS engineering model suffered from microvibration from cryocoolers mounted on the dewar. This is mitigated for the flight model (FM) by introducing vibration isolation systems between the cryocoolers and the dewar. The detector performance of the FM was verified before launch of the spacecraft in both ambient condition and thermal-vacuum condition, showing no detectable degradation in energy resolution. The in-orbit detector spectral performance and cryocooler cooling performance were also consistent with that on ground, indicating that the cryocoolers were not damaged by launch environment. The design and performance of the vibration isolation system along with the mechanism of how the microvibration could degrade the cryogenic detector is shown. Lessons learned from the development to mitigate unexpected issues are also described.
High energy transients: The millisecond domain

NASA Astrophysics Data System (ADS)

Rao, A. R.

2018-02-01

The search for high energy transients in the millisecond domain has come to the focus in recent times due to the detection of gravitational wave events and the identification of fast radio bursts as cosmological sources. Here we highlight the sensitivity limitations in the currently operating hard X-ray telescopes and give some details of the search for millisecond events in the AstroSat CZT Imager data.
Identifying Organic Molecules in Space: The AstroBiology Explorer (ABE) Mission Concept

NASA Technical Reports Server (NTRS)

Ennico, K. A.; Sandford, S. A.; Allamandola, L.; Bregman, J.; Cohen, M.; Cruikshank, D.; Dumas, C.; Greene, T.; Hudgins, D.; Kwok, S.

2004-01-01

The AstroBiology Explorer (ABE) mission concept consists of a dedicated space observatory having a 60 cm class primary mirror cooled to T < 50 K equipped with medium resolution cross-dispersed spectrometers having cooled large format near- and mid-infrared detector arrays. Such a system would be capable of addressing outstanding problems in Astrochemistry and Astrophysics that are particularly relevant to Astrobiology and addressable via astronomical observation. The mission s observational program would make fundamental scientific progress in establishing the nature, distribution, formation and evolution of organic and other molecular materials in the following extra-terrestrial environments: 1) The Outflow of Dying Stars, 2) The Diffuse Interstellar Medium, 3) Dense Molecular Clouds, Star Formation Regions, and Young StellarPlanetary Systems, 4) Planets, Satellites, and Small Bodies within the Solar System, and 5 ) The Interstellar Media of Other Galaxies. ABE could make fundamental progress in all of these areas by conducting a 1 to 2 year mission to obtain a coordinated set of infrared spectroscopic observations over the 2.5-20 micron spectral range at a spectral resolution of R > 2000 of about 1500 objects including galaxies, stars, planetary nebulae, young stellar objects, and solar system objects. Keywords: Astrobiology, infrared, Explorers, interstellar organics, telescope, spectrometer, space, infrared detectors
Magnesium Diboride Current Leads

NASA Technical Reports Server (NTRS)

Panek, John

2010-01-01

A recently discovered superconductor, magnesium diboride (MgB2), can be used to fabricate conducting leads used in cryogenic applications. Dis covered to be superconducting in 2001, MgB2 has the advantage of remaining superconducting at higher temperatures than the previously used material, NbTi. The purpose of these leads is to provide 2 A of electricity to motors located in a 1.3 K environment. The providing environment is a relatively warm 17 K. Requirements for these leads are to survive temperature fluctuations in the 5 K and 11 K heat sinks, and not conduct excessive heat into the 1.3 K environment. Test data showed that each lead in the assembly could conduct 5 A at 4 K, which, when scaled to 17 K, still provided more than the required 2 A. The lead assembly consists of 12 steelclad MgB2 wires, a tensioned Kevlar support, a thermal heat sink interface at 4 K, and base plates. The wires are soldered to heavy copper leads at the 17 K end, and to thin copper-clad NbTi leads at the 1.3 K end. The leads were designed, fabricated, and tested at the Forschungszentrum Karlsruhe - Institut foer Technische Physik before inclusion in Goddard's XRS (X-Ray Spectrometer) instrument onboard the Astro-E2 spacecraft. A key factor is that MgB2 remains superconducting up to 30 K, which means that it does not introduce joule heating as a resistive wire would. Because the required temperature ranges are 1.3-17 K, this provides a large margin of safety. Previous designs lost superconductivity at around 8 K. The disadvantage to MgB2 is that it is a brittle ceramic, and making thin wires from it is challenging. The solution was to encase the leads in thin steel tubes for strength. Previous designs were so brittle as to risk instrument survival. MgB2 leads can be used in any cryogenic application where small currents need to be conducted at below 30 K. Because previous designs would superconduct only at up to 8 K, this new design would be ideal for the 8-30 K range.
Structural insight of the charge-ordering phenomena in manganites

NASA Astrophysics Data System (ADS)

Garcia, Joaquin

2005-03-01

Recent experiments using x-ray absorption spectroscopy (XAS) and x-ray resonant scattering (XRS) techniques show that the conventional description of the so-called charge ordering phases of manganites in terms of Mn^3+/Mn^4+ ionic ordering is far from reality. I present here the XRS study of the low temperature phase of Nd0.5Sr0.5MnO3 manganite. Strong resonances are observed in the energy dependent spectra of (300), (030) and (05/20) reflections. Their azimuthal and polarization dependencies are well explained by the anisotropy of the local geometrical structure. Two different Mn sites were found. One of them is surrounded by a tetragonal distorted oxygen octahedron, whereas the other site has a nearly regular octahedral environment. The charge separation between the intermediate valence states is less than 0.2 e-. The analysis performed resolves some of the apparent contradictions with previous XRS and XAS experiments in manganites. These results joined to those recently obtained on the Verwey transition in magnetite indicate that the electronic states in transition-metal oxides need to be described in terms of band states instead of localized ones. Colaborators: G. Sub'ias, J. Blasco, M. G. Proietti, M. S'anchez and J. Herrero-Martin
The High-Resolution X-Ray Microcalorimeter Spectrometer, SXS, on Astro-H

NASA Technical Reports Server (NTRS)

Mitsuda, Kazuhisa; Kelley, Richard L.; Boyce, Kevin R.; Brown, Gregory V.; Costantini, Elisa; DiPirro, Michael J.; Ezoe, Yuichiro; Fujimoto, Ryuichi; Gendreau, Keith C.; denHerder, Jan-Willem;

2012-01-01

The science and an overview of the Soft X-ray Spectrometer onboard the STRO-H mission are presented. The SXS consists of X-ray focusing mirrors and a microcalorimeter array and is developed by international collaboration lead by JAXA and NASA with European participation. The detector is a 6 x 6 format microcalorimeter array operated at a cryogenic temperature of 50 mK and covers a 3' x 3' field of view of the X-ray telescope of 5.6 m focal length. We expect an energy resolution better than 7 eV (FWHM, requirement) with a goal of 4 eV. The effective area of the instrument will be 225 square centimeters at 7 keV; by a factor of about two larger than that of the X-ray microcalorimeter on board Suzaku. One of the main scientific objectives of the SXS is to investigate turbulent and/or macroscopic motions of hot gas in clusters of galaxies.

Performance of the Three-Stage ADR that Provides Cooling of the Soft X-Ray Spectrometer Aboard Astro-H

NASA Technical Reports Server (NTRS)

Kimball, Mark 0.; Shirron, Peter J.

2011-01-01

The requirements levied upon the cooling system for the soft X-ray spectrometer (SXS) aboard the Astro-H satellite are demanding: Provide an operating temperature of 0.050 degrees Kelvin for a minimum of 24 hours, recycle in less than 2 hours (less than 1 hour in some cases), produce a dipole moment of less than 10 amperes per square meter at the detector location, and do all this with a mass less than 15 kilograms. This is further complicated by the availability of both a 1.3 degrees Kelvin helium bath and a 4.5 degrees Kelvin JT (Joule-Thomson) cooler to recycle the refrigerator. Here we detail the performance of the adiabatic demagnetization refrigerator (ADR) built specifically for SXS that is capable of meeting, and often significantly exceeding, the requirements placed upon it.
MIT-CSR XIS Project

NASA Technical Reports Server (NTRS)

1998-01-01

This report outlines the proposers' progress toward MIT's contribution to the X-Ray Imaging Spectrometer (XIS) experiment on the Japanese ASTRO-E mission. The report discusses electrical system design, mechanical system design, and ground support equipment.
Thermodynamic performance of the 3-stage ADR for the Astro-H Soft-X-ray Spectrometer instrument

NASA Astrophysics Data System (ADS)

Shirron, Peter J.; Kimball, Mark O.; James, Bryan L.; Muench, Theodore; DiPirro, Michael J.; Bialas, Thomas G.; Sneiderman, Gary A.; Porter, Frederick S.; Kelley, Richard L.

2016-03-01

The Soft X-ray Spectrometer (SXS) instrument (Mitsuda et al., 2010) [1] on Astro-H (Takahashi et al., 2010) [2] will use a 3-stage ADR (Shirron et al., 2012) to cool the microcalorimeter array to 50 mK. In the primary operating mode, two stages of the ADR cool the detectors using superfluid helium at ⩽1.20 K as the heat sink (Fujimoto et al., 2010). In the secondary mode, which is activated when the liquid helium is depleted, the ADR uses a 4.5 K Joule-Thomson cooler as its heat sink. In this mode, all three stages operate together to continuously cool the (empty) helium tank and single-shot cool the detectors. The flight instrument - dewar, ADR, detectors and electronics - were integrated in 2014 and have since undergone extensive performance testing. This paper presents a thermodynamic analysis of the ADR's operation, including cooling capacity, heat rejection to the heat sinks, and various measures of efficiency.
Timing of Biochemical Failure and Distant Metastasis for Low, Intermediate, and High Risk Prostate Cancer after Radiotherapy

PubMed Central

Morgan, Peter B.; Hanlon, Alexandra L.; Horwitz, Eric M.; Buyyounouski, Mark K.; Uzzo, Robert G.; Pollack, Alan

2007-01-01

Condensed Abstract The timing of biochemical failure and distant metastasis after radiotherapy for low, intermediate and high-risk prostate cancer was determined. The patterns of failure suggest that the majority of early failures were due to subclinical micrometastases present at diagnosis, whereas a late wave of metastasis at 10–12 years in every risk group was consistent with tumor spread from local persistence of disease. Background The relationship of prostate cancer risk group stratification and the timing of biochemical failure (BF) and distant metastasis (DM) is not well defined. We sought to differentiate early failures due to subclinical micrometastasis at presentation from late failures due to local persistence. Methods A total of 1833 men with clinically localized prostate cancer treated with 3D-conformal radiotherapy with or without short-term androgen deprivation were retrospectively analyzed. The interval hazard rates of DM and BF, using ASTRO and Phoenix (Nadir+2) definitions, were determined for men with low, intermediate, and high risk disease. Results Median follow-up was 67 months. Multivariate analysis showed that increasing risk group was independently associated with higher ASTRO BF (P<.0001) and Nadir+2 BF (P<.0001). The preponderance (87%) of ASTRO BF occurred ≤4 years after RT, while Nadir+2 BF was more evenly spread over years 1–12, with 43% at >4 years. The hazard of Nadir+2 BF persisted in years 8–12 in all risk groups. The interval hazard function for DM appeared to be biphasic (early and late peaks) for intermediate and high risk patients, but no distinct early wave was evident for low risk patients. Conclusions ASTRO BF underestimates late BF due to backdating. Local persistence of disease is suggested by delayed Nadir+2 BF and subsequent late DM in every risk group. The paucity of early DM among those with low risk tumors supports the hypothesis that occult micrometastases contributed to the early wave. PMID:17520705
Molecular dissection of purinergic P2X receptor channels.

PubMed

Stojilkovic, Stanko S; Tomic, Melanija; He, Mu-Lan; Yan, Zonghe; Koshimizu, Taka-Aki; Zemkova, Hana

2005-06-01

The P2X receptors (P2XRs) are a family of ATP-gated channels expressed in the plasma membrane of numerous excitable and nonexcitable cells and play important roles in control of cellular functions, such as neurotransmission, hormone secretion, transcriptional regulation, and protein synthesis. P2XRs are homomeric or heteromeric proteins, formed by assembly of at least three of seven subunits named P2X(1)-P2X(7). All subunits possess intracellular N- and C-termini, two transmembrane domains, and a relatively large extracellular ligand-binding loop. ATP binds to still an unidentified extracellular domain, leading to a sequence of conformational transitions between closed, open, and desensitized states. Removal of extracellular ATP leads to deactivation and resensitization of receptors. Activated P2XRs generate inward currents caused by Na(+) and Ca(2+) influx through the pore of channels, and thus mediate membrane depolarization and facilitation of voltage-gated calcium entry in excitable cells. No crystal structures are available for P2XRs and these receptors have no obvious similarity to other ion channels or ATP binding proteins, which limits the progress in understanding the relationship between molecular structure and conformational transitions of receptor in the presence of agonist and after its washout. We summarize here the alternative approaches in studies on molecular properties of P2XRs, including heteromerization, chimerization, mutagenesis, and biochemical studies.

KARP-1 works as a heterodimer with Ku70, but the function of KARP-1 cannot perfectly replace that of Ku80 in DSB repair

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koike, Manabu, E-mail: m_koike@nirs.go.jp; Yutoku, Yasutomo; Graduate School of Science, Chiba University, Yayoicho, Inage-ku, Chiba 263-8522

2011-10-01

Ku, the heterodimer of Ku70 and Ku80, plays an essential role in the DNA double-strand break (DSB) repair pathway, i.e., non-homologous end-joining (NHEJ). Two isoforms of Ku80 encoded by the same genes, namely, Ku80 and KARP-1 are expressed and function in primate cells, but not in rodent cells. Ku80 works as a heterodimer with Ku70. However, it is not yet clear whether KARP-1 forms a heterodimer with Ku70 and works as a heterodimer. Although KARP-1 appears to work in NHEJ, its physiological role remains unclear. In this study, we established and characterized EGFP-KARP-1-expressing xrs-6 cell lines, EGFP-KARP-1/xrs-6. We found thatmore » nuclear localization signal (NLS) of KARP-1 is localized in the C-terminal region. Our data showed that KARP-1 localizes within the nucleus in NLS-dependent and NLS-independent manner and forms a heterodimer with Ku70, and stabilizes Ku70. On the other hand, EGFP-KARP-1 could not perfectly complement the radiosensitivity and DSB repair activity of Ku80-deficient xrs-6 cells. Furthermore, KARP-1 could not accumulate at DSBs faster than Ku80, although EGFP-KARP-1 accumulates at DSBs. Our data demonstrate that the function of KARP-1 could not perfectly replace that of Ku80 in DSB repair, although KARP-1 has some biochemical properties, which resemble those of Ku80, and works as a heterodimer with Ku70. On the other hand, the number of EGFP-KARP-1-expressing xrs-6 cells showing pan-nuclear {gamma}-H2AX staining significantly increases following X-irradiation, suggesting that KARP-1 may have a novel role in DSB response.« less
The U.S. Spectrum X Gamma Coordination Facility

NASA Astrophysics Data System (ADS)

Forman, William R.

1999-08-01

Spectrum-X-Gamma (SXG) provides for US participation in a first-class international x-ray mission. Despite launch delays, SXG will provide unique scientific opportunities due to its capability for all-sky monitoring, polarimetry, high resolution spectroscopy, and broad wavelength range-from the ultraviolet (TAUVEX and FUVITA), through the x-ray (SODART and JET-X), to the hard x-ray (MART), and gamma-ray burst detectors. Before describing our completed work, we review the unique properties of SXG and provide some examples of the scientific importance of SXG in the Chandra, XMM, and ASTRO-E era.
The U.S. Spectrum X Gamma Coordination Facility

NASA Technical Reports Server (NTRS)

Forman, William R.

1999-01-01

Spectrum-X-Gamma (SXG) provides for US participation in a first-class international x-ray mission. Despite launch delays, SXG will provide unique scientific opportunities due to its capability for all-sky monitoring, polarimetry, high resolution spectroscopy, and broad wavelength range-from the ultraviolet (TAUVEX and FUVITA), through the x-ray (SODART and JET-X), to the hard x-ray (MART), and gamma-ray burst detectors. Before describing our completed work, we review the unique properties of SXG and provide some examples of the scientific importance of SXG in the Chandra, XMM, and ASTRO-E era.
Flight qualified solid argon cooler for the BBXRT instrument. [Broad Band X Ray Telescope for ASTRO-1 payload

NASA Technical Reports Server (NTRS)

Cygnarowicz, Thomas A.; Schein, Michael E.; Lindauer, David A.; Scarlotti, Roger; Pederson, Robert

1990-01-01

A solid argon cooler (SAC) for attached Shuttle payloads has been developed and qualified to meet the need for low cost cooling of flight instruments to the temperature range of 60-120 K. The SACs have been designed and tested with the intent of flying them up to five times. Two coolers, as part of the Broad Band X-ray Telescope (BBXRT) instrument on the ASTRO-1 payload, are awaiting launch on Space Shuttle mission STS-35. This paper describes the design, testing and performance of the SAC and its vacuum maintenance system (VMS), used to maintain the argon as a solid during launch delays of up to 5 days. BBXRT cryogen system design features used to satisfy Shuttle safety requirements are discussed, along with SAC ground servicing equipment (GSE) and procedures used to fill, freeze and subcool the argon.
Development and calibration of fine collimators for the ASTRO-H Soft Gamma-ray Detector

NASA Astrophysics Data System (ADS)

Mizuno, T.; Kimura, D.; Fukazawa, Y.; Furui, S.; Goto, K.; Hayashi, T.; Kawabata, K. S.; Kawano, T.; Kitamura, Y.; Shirakawa, H.; Tanabe, T.; Makishima, K.; Nakajima, K.; Nakazawa, K.; Fukuyama, T.; Ichinohe, Y.; Ishimura, K.; Ohta, M.; Sato, T.; Takahashi, T.; Uchida, Y.; Watanabe, S.; Ishibashi, K.; Sakanobe, K.; Matsumoto, H.; Miyazawa, T.; Mori, H.; Sakai, M.; Tajima, H.

2014-07-01

The Soft Gamma-ray Detector (SGD) is a Si/CdTe Compton telescope surrounded by a thick BGO active shield and is scheduled to be onboard the ASTRO-H satellite when it is launched in 2015. The SGD covers the energy range from 40 to 600 keV with high sensitivity, which allows us to study nonthermal phenomena in the universe. The SGD uses a Compton camera with the narrow field-of-view (FOV) concept to reduce the non-Xray background (NXB) and improve the sensitivity. Since the SGD is essentially a nonimaging instrument, it also has to cope with the cosmic X-ray background (CXB) within the FOV. The SGD adopts passive shields called "fine collimators" (FCs) to restrict the FOV to <= 0.6° for low-energy photons (<= 100 keV), which reduces contamination from CXB to less than what is expected due to NXB. Although the FC concept was already adopted by the Hard X-ray Detector onboard Suzaku, FCs for the SGD are about four times larger in size and are technically more difficult to operate. We developed FCs for the SGD and confirmed that the prototypes function as required by subjecting them to an X-ray test and environmental tests, such as vibration tests. We also developed an autocollimator system, which uses visible light to determine the transmittance and the optical axis, and calibrated it against data from the X-ray test. The acceptance tests of flight models started in December 2013: five out of six FCs were deemed acceptable, and one more unit is currently being produced. The activation properties were studied based on a proton-beam test and the results were used to estimate the in-orbit NXB.
Determining respiratory system resistance and reactance by impulse oscillometry in obese individuals

PubMed Central

de Albuquerque, Cláudio Gonçalves; de Andrade, Flávio Maciel Dias; Rocha, Marcus Aurélio de Almeida; de Oliveira, Alina Farias França; Ladosky, Waldemar; Victor, Edgar Guimarães; Rizzo, José Ângelo

2015-01-01

Objective: To evaluate peripheral respiratory system resistance and reactance (Rrs and Xrs, respectively) in obese individuals. Methods: We recruited 99 individuals, dividing them into four groups by body mass index (BMI): < 30.0 kg/m2 (control, n = 31); 30.0-39.9 kg/m2 (obesity, n = 13); 40.0-49.9 kg/m2 (severe obesity, n = 28); and ≥ 50.0 kg/m2 (morbid obesity, n = 13). Using impulse oscillometry, we measured total Rrs, central Rrs, and Xrs. Peripheral Rrs was calculated as the difference between total Rrs and central Rrs. All subjects also underwent spirometry. Results: Of the 99 individuals recruited, 14 were excluded because they failed to perform forced expiratory maneuvers correctly during spirometry. The individuals in the severe obesity and morbid obesity groups showed higher peripheral Rrs and lower Xrs in comparison with those in the two other groups. Conclusions: Having a BMI ≥ 40 kg/m2 was associated with a significant increase in peripheral Rrs and with a decrease in Xrs. PMID:26578133
WE-E-204-01: ASTRO Based Journals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klein, E.

Research papers authored by Medical Physicists address a large spectrum of oncologic, imaging, or basic research problems; exploit a wide range of physical and engineering methodologies; and often describe the efforts of a multidisciplinary research team. Given dozens of competing journals accepting medical physics articles, it may not be clear to an individual author which journal is the best venue for disseminating their work to the scientific community. Relevant factors usually include the Journal’s audience and scientific impact, but also such factors as perceived acceptance rate, interest in their topic, and quality of service. The purpose of this symposium ismore » to provide the medical physics community with an overview of scope, review processes, and article guidelines for the following journals: Radiology, Medical Physics, International Journal of Radiation Biology and Physics, Journal of Applied Clinical Medical Physics, and Practical Radiation Oncology. Senior members of the editorial board for each journal will provide details as to the journals review process, for example: single blind versus double blind reviews; open access policies, the hierarchy of the review process in terms of editorial board structure; the reality of acceptance, in terms of acceptance rate; and the types of research the journal prefers to publish. Other journals will be discussed as well. The goal is to provide for authors guidance before they begin to write their papers, not only for proper formatting, but also that the readership is appropriate for the particular paper, hopefully increasing the quality and impact of the paper and the likelihood of publication. Learning Objectives: To review each Journal’s submission and review process Guidance as to how to increase quality, impact and chances of acceptance To help decipher which journal is appropriate for a given work A. Karellas, Research collaboration with Koning, Corporation.« less
Thermal design of the hard x-ray imager and the soft gamma-ray detector onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Noda, Hirofumi; Nakazawa, Kazuhiro; Makishima, Kazuo; Iwata, Naoko; Ogawa, Hiroyuki; Ohta, Masayuki; Sato, Goro; Kawaharada, Madoka; Watanabe, Shin; Kokubun, Motohide; Takahashi, Tadayuki; Ohno, Masanori; Fukazawa, Yasushi; Tajima, Hiroyasu; Uchiyama, Hideki; Ito, Shuji; Fukuzawa, Keita

2014-07-01

The Hard X-ray Imager and the Soft Gamma-ray Detector, onboard the 6th Japanese X-ray satellite ASTRO-H, aim at unprecedentedly-sensitive observations in the 5-80 keV and 40-600 keV bands, respectively. Because their main sensors are composed of a number of semi-conductor devices, which need to be operated in a temperature of -20 to -15°C, heat generated in the sensors must be efficiently transported outwards by thermal conduction. For this purpose, we performed thermal design, with the following three steps. First, we additionally included thermally-conductive parts, copper poles and graphite sheets. Second, constructing a thermal mathematical model of the sensors, we estimated temperature distributions in thermal equilibria. Since the model had rather large uncertainties in contact thermal conductions, an accurate thermal dummy was constructed as our final step. Vacuum measurement with the dummy successfully reduced the conductance uncertainties. With these steps, we confirmed that our thermal design of the main sensors satisfies the temperature requirement.
A Three-Year Program of Micro- and Nano-System Technology Development for X-Ray Astronomy

NASA Technical Reports Server (NTRS)

Canizares, Claude R.

1997-01-01

For many years the work at MIT aimed at the development of new concepts and technologies for space experiments in high-energy astrophysics, but not explicitly supported by flight programs, has been supported. This work has yielded new devices and techniques for X-ray astronomy, primarily low-noise, deep-depletion charge-coupled devices (CCDS) for spectrally-resolved X-ray imaging, and high-performance transmission gratings for high-resolution X-ray spectroscopy. Among the most significant recent achievements have been the development by G. Ricker and associates of the X-ray CCD camera flying on ASCA, and currently in development for AXAF and Astro-E, and the development by C. Canizares and associates of thick, 200 nm-period transmission gratings employing the phenomenon of phase shifting for high-resolution X-ray spectroscopy up to energies of 8- 1 0 keV that is essential for the operation of the AXAF High Energy Transmission Grating Spectrometer (HETGS). Through the current SR&T grant, the latter technology is now being extended successfully to the fabrication of 100 nm-period transmission gratings, which have twice the dispersion of the AXAF gratings. We note that, among other outcomes, the modest investments of past SR&T Grants at MIT resulted in the development of the key technologies for fully one-half of the scientific instrumentation on AXAF. In addition, NASA flight programs that have benefited from previous SR&T support at MIT include the SAS 3 X-ray Observatory, which carried the first rotation modulation collimator, the Focal Plane Crystal Spectrometer (FPCS) on the Einstein Observatory, the CCD cameras on ASCA and planned for Astro-E, the High Energy Transient Experiment (HETE), the Solar EUV Monitor on the Solar and Heliospheric Observatory (SOHO), the Medium Energy Neutral Atom imager (MENA) on the Image for Magnetopause-to-aurora Global Exploration (IMAGE) mission, and the recently-approved Two Wide-Angle Imaging Neutral-atom Spectrometers (TWINS
Radiative return capabilities of a high-energy, high-luminosity e + e - collider

DOE PAGES

Karliner, Marek; Low, Matthew; Rosner, Jonathan L.; ...

2015-08-14

An electron-positron collider operating at a center-of-mass energy E CM can collect events at all lower energies through initial-state radiation (ISR or radiative return). We explore the capabilities for radiative return studies by a proposed high-luminosity collider at E CM = 250 or 90 GeV, to fill in gaps left by lower-energy colliders such as PEP, PETRA, TRISTAN, and LEP. These capabilities are compared with those of the lower-energy e +e - colliders as well as hadron colliders such as the Tevatron and the CERN Large Hadron Collider (LHC). Some examples of accessible questions in dark photon searches and heavymore » flavor spectroscopy are given.« less
Operating Modes and Cooling Capabilities of the Flight ADR for the SXS Instrument on Astro-H

NASA Technical Reports Server (NTRS)

Shirron, Peter; Kimball, Mark; DiPirro, Michael

2015-01-01

The microcalorimeter array on the Soft X-ray Spectrometer instrument on Astro-H requires cooling to 50 mK, which will be accomplished by a 3-stage adiabatic demagnetization refrigerator (ADR). The ADR is surrounded by a cryogenic system consisting of a superfluid helium tank, a 4.5 K Joule-Thomson (JT) cryocooler, and additional 2-stage Stirling cryocoolers that pre-cool the JT cooler and radiation shields within the cryostat. The unique ADR design allows the instrument to meet all of its science requirements using either the stored cryogen or the JT cryocooler as its heat sink, giving the instrument an unusual degree of tolerance for component failures or degradation in the cryogenic system. The flight detector assembly, ADR and dewar were integrated in early 2014, and have since been extensively characterized and calibrated. At present, the four instruments are being integrated with the spacecraft in preparation for an early 2016 launch. This presentation summarizes the operation and performance of the ADR in all of its operating modes.
The Design, Implementation, and Performance of the Astro-H SXS Aperture Assembly and Blocking Filters

NASA Technical Reports Server (NTRS)

Kilbourne, C. A.; Adams, J. S.; Arsenovic, P.; Ayers, T.; Chiao, M. P.; DiPirro, M. J.; Eckart, M. E.; Fujimoto, R.; Kazeva, J. D.; Kelley, R. L.;

2016-01-01

The calorimeter array of the JAXA Astro-H (renamed Hitomi) Soft X-ray Spectrometer (SXS) was designed to provide unprecedented spectral resolution of spatially extended cosmic x-ray sources and of all cosmic x-ray sources in the Fe-K band around 6 keV. The properties that make the SXS a powerful x-ray spectrometer also make it sensitive to the entire electromagnetic band. If characterized as a bolometer, it would have a noise equivalent power (NEP) of < 4x10(exp -18) W/(Hz)0.5. Thus it was imperative to shield the detector from thermal radiation from the instrument and optical and UV photons from the sky. Additionally, it was necessary to shield the coldest stages of the instrument from the thermal radiation emanating from the warmer stages. These needs are addressed by a series of five thin-film radiation blocking filters that block long-wavelength radiation while minimizing x-ray attenuation. The SXS aperture assembly is a system of barriers, baffles, filter carriers, and filter mounts that supports the filters and inhibits their potential contamination. The three warmer filters also were equipped with thermometers and heaters for decontamination.

Teaching Advanced Data Analysis Tools to High School Astronomy Students

NASA Astrophysics Data System (ADS)

Black, David V.; Herring, Julie; Hintz, Eric G.

2015-01-01

A major barrier to becoming an astronomer is learning how to analyze astronomical data, such as using photometry to compare the brightness of stars. Most fledgling astronomers learn observation, data reduction, and analysis skills through an upper division college class. If the same skills could be taught in an introductory high school astronomy class, then more students would have an opportunity to do authentic science earlier, with implications for how many choose to become astronomers. Several software tools have been developed that can analyze astronomical data ranging from fairly straightforward (AstroImageJ and DS9) to very complex (IRAF and DAOphot). During the summer of 2014, a study was undertaken at Brigham Young University through a Research Experience for Teachers (RET) program to evaluate the effectiveness and ease-of-use of these four software packages. Standard tasks tested included creating a false-color IR image using WISE data in DS9, Adobe Photoshop, and The Gimp; a multi-aperture analyses of variable stars over time using AstroImageJ; creating Spectral Energy Distributions (SEDs) of stars using photometry at multiple wavelengths in AstroImageJ and DS9; and color-magnitude and hydrogen alpha index diagrams for open star clusters using IRAF and DAOphot. Tutorials were then written and combined with screen captures to teach high school astronomy students at Walden School of Liberal Arts in Provo, UT how to perform these same tasks. They analyzed image data using the four software packages, imported it into Microsoft Excel, and created charts using images from BYU's 36-inch telescope at their West Mountain Observatory. The students' attempts to complete these tasks were observed, mentoring was provided, and the students then reported on their experience through a self-reflection essay and concept test. Results indicate that high school astronomy students can successfully complete professional-level astronomy data analyses when given detailed
Onboard data-processing architecture of the soft X-ray imager (SXI) on NeXT satellite

NASA Astrophysics Data System (ADS)

Ozaki, Masanobu; Dotani, Tadayasu; Tsunemi, Hiroshi; Hayashida, Kiyoshi; Tsuru, Takeshi G.

2004-09-01

NeXT is the X-ray satellite proposed for the next Japanese space science mission. While the satellite total mass and the launching vehicle are similar to the prior satellite Astro-E2, the sensitivity is much improved; it requires all the components to be lighter and faster than previous architecture. This paper shows the data processing architecture of the X-ray CCD camera system SXI (Soft X-ray Imager), which is the top half of the WXI (Wide-band X-ray Imager) of the sensitivity in 0.2-80keV. The system is basically a variation of Astro-E2 XIS, but event extraction speed is much faster than it to fulfill the requirements coming from the large effective area and fast exposure period. At the same time, data transfer lines between components are redesigned in order to reduce the number and mass of the wire harnesses that limit the flexibility of the component distribution.
Venus Measurements by the MESSENGER Gamma-Ray and X-Ray Spectrometers

NASA Astrophysics Data System (ADS)

Rhodes, E. A.; Starr, R. D.; Goldsten, J. O.; Schlemm, C. E.; Boynton, W. V.

2007-12-01

The Gamma-Ray Spectrometer (GRS), which is a part of the Gamma-Ray and Neutron Spectrometer Instrument, and the X-Ray Spectrometer (XRS) on the MESSENGER spacecraft made calibration measurements during the Venus flyby on June 5, 2007. The purpose of these instruments is to determine elemental abundances on the surface of Mercury. The GRS measures gamma-rays emitted from element interactions with cosmic rays impinging on the surface, while the XRS measures X-ray emissions induced on the surface by the incident solar flux. The GRS sensor is a high-resolution high-purity Ge detector cooled by a Stirling cryocooler, surrounded by a borated-plastic anticoincidence shield. The GRS is sensitive to gamma-rays up to ~10 MeV and can identify most major elements, sampling down to depths of about ten centimeters. Only the shield was powered on for this flyby in order to conserve cooler lifetime. Gamma-rays were observed coming from Venus as well as from the spacecraft. Although the Venus gamma-rays originate from its thick atmosphere rather than its surface, the GRS data from this encounter will provide useful calibration data from a source of known composition. In particular, the data will be useful for determining GRS sensitivity and pointing options for the Mercury flybys, the first of which will be in January 2008. The X-ray spectrum of a planetary surface is dominated by a combination of the fluorescence and scattered solar X-rays. The most prominent fluorescent lines are the Kα lines from the major elements Mg, Al, Si, S, Ca, Ti, and Fe (1-10 keV). The sampling depth is less than 100 u m. The XRS is similar in design to experiments flown on Apollo 15 and 16 and the NEAR-Shoemaker mission. Three large-area gas-proportional counters view the planet, and a small Si-PIN detector mounted on the spacecraft sunshade monitors the Sun. The energy resolution of the gas proportional counters (~850 eV at 5.9 keV) is sufficient to resolve the X-ray lines above 2 keV, but Al and Mg
"ASTRO 101" Course Materials 2.0: Next Generation Lecture Tutorials and Beyond

NASA Astrophysics Data System (ADS)

Slater, Stephanie; Grazier, Kevin

2015-01-01

Early efforts to create course materials were often local in scale and were based on "gut instinct," and classroom experience and observation. While subsequent efforts were often based on those same instincts and observations of classrooms, they also incorporated the results of many years of education research. These "second generation" course materials, such as lecture tutorials, relied heavily on research indicating that instructors need to actively engage students in the learning process. While imperfect, these curricular innovations, have provided evidence that research-based materials can be constructed, can easily be disseminated to a broad audience, and can provide measureable improvement in student learning across many settings. In order to improve upon this prior work, next generation materials must build upon the strengths of these innovations while engineering in findings from education research, cognitive science, and instructor feedback. A next wave of materials, including a set of next generation lecture tutorials, have been constructed with attention to the body of research on student motivation, and cognitive load; and they are responsive to our body of knowledge on learning difficulties related to specific content in the domain. From instructor feedback, these materials have been constructed to have broader coverage of the materials typically taught in an ASTRO 101 course, to take less class time, and to be more affordable for students. This next generation of lecture tutorials may serve as a template of the ways in which course materials can be reengineered to respond to current instructor and student needs.
A special report of current state of the medical physicist workforce — results of the 2012 ASTRO Comprehensive Workforce Study

PubMed Central

Arnone, Anna; Sillanpaa, Jussi K; Yu, Yan; Mills, Michael D.

2015-01-01

The medical physics profession is undergoing significant changes. Starting in 2014, candidates registering for certification exams by the American Board of Radiology must have completed a CAMPEP‐accredited residency. This requirement, along with tightened state regulations, uncertainty in future reimbursement, and a stronger emphasis on board certification, have raised questions concerning the state of the medical physics workforce and its ability to adapt to changing requirements. In 2012, ASTRO conducted a workforce study of the comprehensive field of radiation oncology. This article reviews the findings of the medical physics section of the study, including age and gender distribution, educational background, workload, and primary work setting. We also report on job satisfaction, the perceived supply and demand of medical physicists, and the medical physicists' main concerns pertaining to patient safety and quality assurance. PACS number: 87.90 PMID:26103483
Intelligent error correction method applied on an active pixel sensor based star tracker

NASA Astrophysics Data System (ADS)

Schmidt, Uwe

2005-10-01

Star trackers are opto-electronic sensors used on-board of satellites for the autonomous inertial attitude determination. During the last years star trackers became more and more important in the field of the attitude and orbit control system (AOCS) sensors. High performance star trackers are based up today on charge coupled device (CCD) optical camera heads. The active pixel sensor (APS) technology, introduced in the early 90-ties, allows now the beneficial replacement of CCD detectors by APS detectors with respect to performance, reliability, power, mass and cost. The company's heritage in star tracker design started in the early 80-ties with the launch of the worldwide first fully autonomous star tracker system ASTRO1 to the Russian MIR space station. Jena-Optronik recently developed an active pixel sensor based autonomous star tracker "ASTRO APS" as successor of the CCD based star tracker product series ASTRO1, ASTRO5, ASTRO10 and ASTRO15. Key features of the APS detector technology are, a true xy-address random access, the multiple windowing read out and the on-chip signal processing including the analogue to digital conversion. These features can be used for robust star tracking at high slew rates and under worse conditions like stray light and solar flare induced single event upsets. A special algorithm have been developed to manage the typical APS detector error contributors like fixed pattern noise (FPN), dark signal non-uniformity (DSNU) and white spots. The algorithm works fully autonomous and adapts to e.g. increasing DSNU and up-coming white spots automatically without ground maintenance or re-calibration. In contrast to conventional correction methods the described algorithm does not need calibration data memory like full image sized calibration data sets. The application of the presented algorithm managing the typical APS detector error contributors is a key element for the design of star trackers for long term satellite applications like
The Quantitative Reasoning for College Science (QuaRCS) Assessment in non-Astro 101 Courses II

NASA Astrophysics Data System (ADS)

Kirkman, Thomas W.; Jensen, Ellen

2017-06-01

The Quantitative Reasoning for College Science (QuaRCS) Assessment[1] aims to measure the pre-algebra mathematical skills that are often part of "general education" science courses like Astro 101. In four majors STEM classes, we report comparisons between QuaRCS metrics, ACT math, GPAO, and the course grade. In three of four classes QuaRCS QR score and ACT math were statistically significantly correlated (with r˜.6), however in the fourth course —a senior-level microbiology course— there was no statistically significantly correlation (in fact, r<0). In all courses —even in courses with seemingly little quantitative content— course grade was statistically significantly correlated to GPAO and QR. A QuaRCS metric aiming to report the students belief in the importance of math in science was seen to grow with the course level. Pre/post QuaRCS testing in Physics courses showed fractional sigma gains in QR, self-estimated math fluency and math importance, but not all of those increases were statistically significant. Using a QuaRCS map relating the questions to skill areas, we found graph reading, percentages, and proportional reasoning to be the most misunderstood skills in all four courses.[1] QuaRCS, Follette, et al.,2015, DOI: http://dx.doi.org/10.5038/1936-4660.8.2.2
The Effect of Interactive Instruction in the Astro 101 Classroom: Report on a National Study

NASA Astrophysics Data System (ADS)

Rudolph, Alexander L.; Prather, E. E.; Brissenden, G.; Consiglio, D.; Schlingman, W. M.; Gonzaga, V.; Collaboration of Astronomy Teaching Scholars CATS

2011-01-01

We have conducted a national research study designed to determine the effect of interactive learning strategies on students' conceptual learning in general education astronomy courses (Astro 101). Nearly 4000 students at 31 institutions, (4-year and 2-year) around the country participated in the study. Our results show dramatic improvement in student learning with increased use of interactive learning strategies independent of institution type or class size, and after controlling for individual student characteristics. In addition, we find that the positive effects of interactive learning strategies apply equally to men and women, across ethnicities, for students with all levels of prior mathematical preparation and physical science course experience, independent of GPA, and regardless of primary language. These results powerfully illustrate that all categories of students can benefit from the effective implementation of interactive learning strategies. This material is based upon work supported by the National Science Foundation under Award No. 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS) Program, and Award No. 0847170, a PAARE grant funding the California-Arizona Minority Partnership for Astronomy Research and Education (CAMPARE). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

Yeast MRX deletions have short chronological life span and more triacylglycerols.

PubMed

Kanagavijayan, Dhanabalan; Rajasekharan, Ram; Srinivasan, Malathi

2016-02-01

Saccharomyces cerevisiae is an excellent model organism for lipid research. Here, we have used yeast haploid RAdiation Damage (RAD) deletion strains to study life span and lipid storage patterns. RAD genes are mainly involved in DNA repair mechanism and hence, their deletions have resulted in shorter life span. Viable RAD mutants were screened for non-polar lipid content, and some of the mutants showed significantly high amounts of triacylglycerol (TAG) and steryl ester, besides short chronological life span. Among these, RAD50, MRE11 and XRS2 form a complex, MRX that is involved in homologous recombination that showed an increase in the amount of TAG. Microarray data of single MRX deletions revealed that besides DNA damage signature genes, lipid metabolism genes are also differentially expressed. Lipid biosynthetic genes (LPP1, SLC1) were upregulated and lipid hydrolytic gene (TGL3) was downregulated. We observed that rad50Δ, mre11Δ, xrs2Δ and mrxΔ strains have high number of lipid droplets (LDs) with fragmented mitochondria. These mutants have a short chronological life span compared to wild type. Aged wild-type cells also accumulated TAG with LDs of ∼2.0 μm in diameter. These results suggest that TAG accumulation and big size LDs could be possible markers for premature or normal aging. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
LICA AstroCalc, a software to analyze the impact of artificial light: Extracting parameters from the spectra of street and indoor lamps

NASA Astrophysics Data System (ADS)

Ayuga, Carlos Eugenio Tapia; Zamorano, Jaime

2018-07-01

The night sky spectra of light-polluted areas is the result of the artificial light scattered back from the atmosphere and the reemission of the light after reflections in painted surfaces. This emission comes mainly from street and decorative lamps. We have built an extensive database of lamps spectra covering from UV to near IR and the software needed to analyze them. We describe the LICA-AstroCalc free software that is a user friendly GUI tool to extract information from our database spectra or any other user provided spectrum. The software also includes the complete color database of paints from NCS comprising 1950 types. This helps to evaluate how different colors modify the reflected spectra from different lamps. All spectroscopic measurements have been validated with recommendations from CIELAB and ISO from NCS database.
Response localization of the pharmacological agents histamine and salbutamol along the respiratory system by forced oscillations in asthmatic subjects.

PubMed

Wouters, E F; Polko, A H; Visser, B F

1989-01-01

The bronchodilating effect of 1 mg and 0.4 mg salbutamol on the impedance of the respiratory system was studied in 25 asthmatic subjects after histamine-induced bronchoconstriction. Histamine caused an increase of respiratory resistance (Rrs) at lower frequencies and a frequency dependence of Rrs. Respiratory reactance (Xrs) decreased at all frequencies after histamine challenge. These changes can be explained by peripheral airway obstruction. Impedance measurements performed 5 min after inhalation of 1 mg and 0.4 mg salbutamol showed a decrease of Rrs values at lower frequencies, a disappearance of the frequency dependence of Rrs, and a significant increase of Xrs values. No significant differences in absolute changes of Rrs and Xrs are observed between the salbutamol regimens. These changes after inhalation of salbutamol can be explained by supposing a predominant action on the peripheral airways.
Performance verification and system integration tests of the pulse shape processor for the soft x-ray spectrometer onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Takeda, Sawako; Tashiro, Makoto S.; Ishisaki, Yoshitaka; Tsujimoto, Masahiro; Seta, Hiromi; Shimoda, Yuya; Yamaguchi, Sunao; Uehara, Sho; Terada, Yukikatsu; Fujimoto, Ryuichi; Mitsuda, Kazuhisa

2014-07-01

The soft X-ray spectrometer (SXS) aboard ASTRO-H is equipped with dedicated digital signal processing units called pulse shape processors (PSPs). The X-ray microcalorimeter system SXS has 36 sensor pixels, which are operated at 50 mK to measure heat input of X-ray photons and realize an energy resolution of 7 eV FWHM in the range 0.3-12.0 keV. Front-end signal processing electronics are used to filter and amplify the electrical pulse output from the sensor and for analog-to-digital conversion. The digitized pulses from the 36 pixels are multiplexed and are sent to the PSP over low-voltage differential signaling lines. Each of two identical PSP units consists of an FPGA board, which assists the hardware logic, and two CPU boards, which assist the onboard software. The FPGA board triggers at every pixel event and stores the triggering information as a pulse waveform in the installed memory. The CPU boards read the event data to evaluate pulse heights by an optimal filtering algorithm. The evaluated X-ray photon data (including the pixel ID, energy, and arrival time information) are transferred to the satellite data recorder along with event quality information. The PSP units have been developed and tested with the engineering model (EM) and the flight model. Utilizing the EM PSP, we successfully verified the entire hardware system and the basic software design of the PSPs, including their communication capability and signal processing performance. In this paper, we show the key metrics of the EM test, such as accuracy and synchronicity of sampling clocks, event grading capability, and resultant energy resolution.
Proton radiation damage experiment on P-Channel CCD for an X-ray CCD camera onboard the ASTRO-H satellite

NASA Astrophysics Data System (ADS)

Mori, Koji; Nishioka, Yusuke; Ohura, Satoshi; Koura, Yoshiaki; Yamauchi, Makoto; Nakajima, Hiroshi; Ueda, Shutaro; Kan, Hiroaki; Anabuki, Naohisa; Nagino, Ryo; Hayashida, Kiyoshi; Tsunemi, Hiroshi; Kohmura, Takayoshi; Ikeda, Shoma; Murakami, Hiroshi; Ozaki, Masanobu; Dotani, Tadayasu; Maeda, Yukie; Sagara, Kenshi

2013-12-01

We report on a proton radiation damage experiment on P-channel CCD newly developed for an X-ray CCD camera onboard the ASTRO-H satellite. The device was exposed up to 109 protons cm-2 at 6.7 MeV. The charge transfer inefficiency (CTI) was measured as a function of radiation dose. In comparison with the CTI currently measured in the CCD camera onboard the Suzaku satellite for 6 years, we confirmed that the new type of P-channel CCD is radiation tolerant enough for space use. We also confirmed that a charge-injection technique and lowering the operating temperature efficiently work to reduce the CTI for our device. A comparison with other P-channel CCD experiments is also discussed. We performed a proton radiation damage experiment on a new P-channel CCD. The device was exposed up to 109 protons cm-2 at 6.7 MeV. We confirmed that it is radiation tolerant enough for space use. We confirmed that a charge-injection technique reduces the CTI. We confirmed that lowering the operating temperature also reduces the CTI.
@Astro_Wheels Tweetup

NASA Image and Video Library

2011-03-16

Astronaut Doug Wheelock discusses his experiences while living on the International Space Station during a tweetup at NASA Headquarters in Washington, Wednesday, March 16, 2011. Wheelock, who has accumulated a total of 178 days in space, assumed command of the International Space Station and the Expedition 25 crew. During Expedition 25, there were more than 120 microgravity experiments in human research; biology and biotechnology; physical and materials sciences; technology development; and Earth and space sciences. Wheelock also responded to an emergency shutdown of half of the station's external cooling system and supported three unplanned spacewalks to replace the faulty pump module that caused the shutdown. His efforts restored the station's critical cooling system to full function. The mission duration was 163 days. Photo Credit: (NASA/Paul E. Alers)
High efficiency GaP power conversion for Betavoltaic applications

NASA Astrophysics Data System (ADS)

Sims, Paul E.; Dinetta, Louis C.; Barnett, Allen M.

1994-09-01

AstroPower is developing a gallium phosphide (GaP) based energy converter optimized for radio luminescent light-based power supplies. A 'two-step' or 'indirect' process is used where a phosphor is excited by radioactive decay products to produce light that is then converted to electricity by a photovoltaic energy converter. This indirect conversion of beta-radiation to electrical energy can be realized by applying recent developments in tritium based radio luminescent (RL) light sources in combination with the high conversion efficiencies that can be achieved under low illumination with low leakage, gallium phosphide based devices. This tritium to light approach is inherently safer than battery designs that incorporate high activity radionuclides because the beta particles emitted by tritium are of low average energy and are easily stopped by a thin layer of glass. GaP layers were grown by liquid phase epitaxy and p/n junction devices were fabricated and characterized for low light intensity power conversion. AstroPower has demonstrated the feasibility of the GaP based energy converter with the following key results: 23.54 percent conversion efficiency under 968 muW/sq cm 440 nm blue light, 14.59 percent conversion efficiency for 2.85 muW/sq cm 440 nm blue light, and fabrication of working 5 V array. We have also determined that at least 20 muW/sq cm optical power is available for betavoltaic power systems. Successful developments of this device is an enabling technology for low volume, safe, high voltage, milliwatt power supplies with service lifetimes in excess of 12 years.
High efficiency GaP power conversion for Betavoltaic applications

NASA Technical Reports Server (NTRS)

Sims, Paul E.; Dinetta, Louis C.; Barnett, Allen M.

1994-01-01

AstroPower is developing a gallium phosphide (GaP) based energy converter optimized for radio luminescent light-based power supplies. A 'two-step' or 'indirect' process is used where a phosphor is excited by radioactive decay products to produce light that is then converted to electricity by a photovoltaic energy converter. This indirect conversion of beta-radiation to electrical energy can be realized by applying recent developments in tritium based radio luminescent (RL) light sources in combination with the high conversion efficiencies that can be achieved under low illumination with low leakage, gallium phosphide based devices. This tritium to light approach is inherently safer than battery designs that incorporate high activity radionuclides because the beta particles emitted by tritium are of low average energy and are easily stopped by a thin layer of glass. GaP layers were grown by liquid phase epitaxy and p/n junction devices were fabricated and characterized for low light intensity power conversion. AstroPower has demonstrated the feasibility of the GaP based energy converter with the following key results: 23.54 percent conversion efficiency under 968 muW/sq cm 440 nm blue light, 14.59 percent conversion efficiency for 2.85 muW/sq cm 440 nm blue light, and fabrication of working 5 V array. We have also determined that at least 20 muW/sq cm optical power is available for betavoltaic power systems. Successful developments of this device is an enabling technology for low volume, safe, high voltage, milliwatt power supplies with service lifetimes in excess of 12 years.
The Robotic Hugo E. Schwarz Telescope | CTIO

Science.gov Websites

Program PIA Program GO-FAAR Program Other Opportunities Tourism Visits to Tololo Astro tourism in Chile Tourism in Chile Information for travelers Visit Tololo Media Relations News Press Release Publications of a new electronic drive system for the mount, and the second, dedicate to re-design the dome
@Astro_Wheels Tweetup

NASA Image and Video Library

2011-03-16

A tweetuup participant videotapes with her iPhone and tweets as astronaut Doug Wheelock discusses his experiences while living on the International Space Station during a tweetup at NASA Headquarters in Washington, Wednesday, March 16, 2011. Wheelock, who has accumulated a total of 178 days in space, assumed command of the International Space Station and the Expedition 25 crew. During Expedition 25, there were more than 120 microgravity experiments in human research; biology and biotechnology; physical and materials sciences; technology development; and Earth and space sciences. Wheelock also responded to an emergency shutdown of half of the station's external cooling system and supported three unplanned spacewalks to replace the faulty pump module that caused the shutdown. His efforts restored the station's critical cooling system to full function. The mission duration was 163 days. Photo Credit: (NASA/Paul E. Alers)
Operating Modes and Cooling Capabilities of the 3-Stage ADR Developed for the Soft-X-ray Spectrometer Instrument on Astro-H

PubMed Central

Shirron, Peter J; Kimball, Mark O; James, Bryan L; Muench, Theo; DiPirro, Michael J; Letmate, Richard V; Sampson, Michael A; Bialas, Tom G; Sneiderman, Gary A; Porter, Frederick S; Kelley, Richard L

2017-01-01

A 3-stage adiabatic demagnetization refrigerator (ADR)[1] is used on the Soft X-ray Spectrometer instrument[2] on Astro-H[3] to cool a 6×6 array of x-ray microcalorimeters to 50 mK. The ADR is supported by a cryogenic system[4] consisting of a superfluid helium tank, a 4.5 K Joule-Thomson (JT) cryocooler, and additional 2-stage Stirling cryocoolers that pre-cool the JT cooler and cool radiation shields within the cryostat. The ADR is configured so that it can use either the liquid helium or the JT cryocooler as its heat sink, giving the instrument an unusual degree of tolerance for component failures or degradation in the cryogenic system. The flight detector assembly, ADR and dewar were integrated into the flight dewar in early 2014, and have since been extensively characterized and calibrated. This paper summarizes the operation and performance of the ADR in all of its operating modes. PMID:28111478
Operating Modes and Cooling Capabilities of the 3-Stage ADR Developed for the Soft-X-ray Spectrometer Instrument on Astro-H.

PubMed

Shirron, Peter J; Kimball, Mark O; James, Bryan L; Muench, Theo; DiPirro, Michael J; Letmate, Richard V; Sampson, Michael A; Bialas, Tom G; Sneiderman, Gary A; Porter, Frederick S; Kelley, Richard L

2016-03-01

A 3-stage adiabatic demagnetization refrigerator (ADR)[1] is used on the Soft X-ray Spectrometer instrument[2] on Astro-H[3] to cool a 6×6 array of x-ray microcalorimeters to 50 mK. The ADR is supported by a cryogenic system[4] consisting of a superfluid helium tank, a 4.5 K Joule-Thomson (JT) cryocooler, and additional 2-stage Stirling cryocoolers that pre-cool the JT cooler and cool radiation shields within the cryostat. The ADR is configured so that it can use either the liquid helium or the JT cryocooler as its heat sink, giving the instrument an unusual degree of tolerance for component failures or degradation in the cryogenic system. The flight detector assembly, ADR and dewar were integrated into the flight dewar in early 2014, and have since been extensively characterized and calibrated. This paper summarizes the operation and performance of the ADR in all of its operating modes.
Operating Modes and Cooling Capabilities of the 3-Stage ADR Developed for the Soft-X-Ray Spectrometer Instrument on Astro-H

NASA Technical Reports Server (NTRS)

Shirron, Peter J.; Kimball, Mark O.; James, Bryan L.; Muench, Theo; DiPirro, Michael J.; Letmate, Richard V.; Sampson, Michael A.; Bialas, Tom G.; Sneiderman, Gary A.; Porter, Frederick S.;

2015-01-01

A 3-stage adiabatic demagnetization refrigerator (ADR) is used on the Soft X-ray Spectrometer instrument on Astro-H to cool a 6x6 array of x-ray microcalorimeters to 50 mK. The ADR is supported by a cryogenic system consisting of a superfluid helium tank, a 4.5 K Joule-Thomson (JT) cryocooler, and additional 2-stage Stirling cryocoolers that pre-cool the JT cooler and cool radiation shields within the cryostat. The ADR is configured so that it can use either the liquid helium or the JT cryocooler as its heat sink, giving the instrument an unusual degree of tolerance for component failures or degradation in the cryogenic system. The flight detector assembly, ADR and dewar were integrated into the flight dewar in early 2014, and have since been extensively characterized and calibrated. This paper summarizes the operation and performance of the ADR in all of its operating modes

Lab Astro and the Origins of the Chemical Elements

NASA Astrophysics Data System (ADS)

Lawler, James E.

2010-03-01

Interpretation of the spectra of metal-poor Galactic halo stars is dependent on AMO laboratory data [1,2]. Metal-poor Galactic halo stars were born when the Milky Way was young and they provide a record of the chemical evolution of the Galaxy. Elements heavier than iron are produced via r(apid)-process and s(low)-process n(eutron)-capture mechanisms. The s-process mechanism, which occurs in certain AGB stars, is relatively well understood. The explosive r-process is not well understood. The r-process n-capture mechanism was dominant early in the Galaxy's history [3]. New large aperture telescopes make it possible to record high-resolution spectra with high signal-to-noise ratios on a growing number of metal-poor stars. In addition to mapping the chemical evolution of the Galaxy, these studies are yielding an increasingly well-defined r-process elemental abundance pattern which constrains models of r-process nucleosynthesis [1]. The next phase of this ongoing research will address challenges in modeling stellar photospheres. Peculiar trends in abundances of specific Fe-group elements as a function of stellar age or metallicity may be due to limitations in traditional one dimensional (1d) local thermodynamic equilibrium (LTE) models of stellar photospheres or may be due to poorly understood nucleosynthesis [4]. Efforts are now underway to test the Saha or ionization equilibrium in a variety of stellar atmospheres for several Fe-group elements using the best available spectroscopic data for selected transitions. More comprehensive spectroscopic data of improved accuracy and accurate collisional data, especially for inelastic collisions of H atoms with metal atoms and ions, will be needed to fully develop 3d/non-LTE models of photospheres [e.g. 5]. [4pt] [1] C. Sneden, J. E. Lawler, J. J. Cowan, I. I. Ivans, and E. A. Den Hartog, Astrophys. J. Suppl. Ser. 182, 80-96 (2009). [0pt] [2] J. E. Lawler, C. Sneden, J. J. Cowan, I. I. Ivans, and E. A. Den Hartog, Astrophys. J
American Society for Radiation Oncology (ASTRO) Survey of Radiation Biology Educators in U.S. and Canadian Radiation Oncology Residency Programs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosenstein, Barry S., E-mail: barry.rosenstein@mssm.ed; Department of Radiation Oncology, New York University School of Medicine, New York, NY; Held, Kathryn D.

2009-11-01

Purpose: To obtain, in a survey-based study, detailed information on the faculty currently responsible for teaching radiation biology courses to radiation oncology residents in the United States and Canada. Methods and Materials: In March-December 2007 a survey questionnaire was sent to faculty having primary responsibility for teaching radiation biology to residents in 93 radiation oncology residency programs in the United States and Canada. Results: The responses to this survey document the aging of the faculty who have primary responsibility for teaching radiation biology to radiation oncology residents. The survey found a dramatic decline with time in the percentage of educatorsmore » whose graduate training was in radiation biology. A significant number of the educators responsible for teaching radiation biology were not fully acquainted with the radiation sciences, either through training or practical application. In addition, many were unfamiliar with some of the organizations setting policies and requirements for resident education. Freely available tools, such as the American Society for Radiation Oncology (ASTRO) Radiation and Cancer Biology Practice Examination and Study Guides, were widely used by residents and educators. Consolidation of resident courses or use of a national radiation biology review course was viewed as unlikely by most programs. Conclusions: A high priority should be given to the development of comprehensive teaching tools to assist those individuals who have responsibility for teaching radiation biology courses but who do not have an extensive background in critical areas of radiobiology related to radiation oncology. These findings also suggest a need for new graduate programs in radiobiology.« less
The Design, Implementation, and Performance of the Astro-H SXS Aperture Assembly and Blocking Filters

NASA Technical Reports Server (NTRS)

Kilbourne, Caroline A.; Adams, Joseph S.; Arsenovic, Petar; Ayers, Travis; Chiao, Meng P.; DiPirro, Michael J.; Eckart, Megan E.; Fujimoto, Ryuichi; Kazeva, John D.; Kelley, Richard L.;

2016-01-01

The calorimeter array of the JAXA Astro-H (renamed Hitomi) Soft X-ray Spectrometer (SXS) was designed to provide unprecedented spectral resolution of spatially extended cosmic x-ray sources and of all cosmic x-ray sources in the Fe-K band around 6 keV, enabling essential plasma diagnostics. The properties that make the SXS array a powerful x-ray spectrometer also make it sensitive to photons from the entire electromagnetic band, and particles as well. If characterized as a bolometer, it would have a noise equivalent power (NEP) of less than 4x10(exp -18) W/(Hz)0.5(exp 0.5). Thus it was imperative to shield the detector from thermal radiation from the instrument and optical and UV photons from the sky. Additionally, it was necessary to shield the coldest stages of the instrument from the thermal radiation emanating from the warmer stages. Both of these needs are addressed by a series of five thin-film radiation-blocking filters, anchored to the nested temperature stages, that block long-wavelength radiation while minimizing x-ray attenuation. The aperture assembly is a system of barriers, baffles, filter carriers, and filter mounts that supports the filters and inhibits their potential contamination. The three outer filters also have been equipped with thermometers and heaters for decontamination. We present the requirements, design, implementation, and performance of the SXS aperture assembly and blocking filters.

A New Observation of the Quiet Sun Soft X-ray (0.5-5 keV) Spectrum

NASA Astrophysics Data System (ADS)

Caspi, A.; Woods, T. N.; Stone, J.

2012-12-01

The solar corona is the brightest source of X-rays in the solar system, and the X-ray emission is highly variable with solar activity. While this is particularly true during solar flares, when emission can be enhanced by many orders of magnitude up to gamma-ray energies, even the so-called "quiet Sun" is bright in soft X-rays (SXRs), as the ~1-2 MK ambient plasma of the corona emits significant thermal bremsstrahlung up to ~5 keV. However, the actual solar SXR (0.5-5 keV) spectrum is not well known, particularly during quiet periods, as, with few exceptions, this energy range has not been systematically studied in many years. Previous observations include ultra-high-resolution but very narrow-band spectra from crystral spectrometers (e.g. Yohkoh/BCS), or integrated broadband irradiances from photometers (e.g. GOES/XRS, TIMED/XPS, etc.) that lack detailed spectral information. In recent years, broadband measurements with fair energy resolution (~0.5-0.7 keV FWHM) were made by SphinX on CORONAS-Photon and XRS on MESSENGER, although they did not extend below ~1 keV. We present observations of the quiet Sun SXR emission obtained using a new SXR spectrometer flown on the third SDO/EVE underflight calibration rocket (NASA 36.286). The commercial off-the-shelf Amptek X123 silicon drift detector, with an 8-micron Be window and custom aperture, measured the solar SXR emission from ~0.5 to >10 keV with ~0.15 keV FWHM resolution (though, due to hardware limitations, with only ~0.12 keV binning) and 2-sec cadence over ~5 minutes on 23 June 2012. Despite the rising solar cycle, activity on 23 June 2012 was abnormally low, with no visible active regions and GOES XRS emission near 2010 levels; we measured no solar counts above ~4 keV during the observation period. We compare our X123 measurements with spectra and broadband irradiances from other instruments, including the SphinX observations during the deep solar minimum of 2009, and with upper limits of >3 keV quiet Sun emission
A New Observation of the Quiet Sun Soft X-ray (0.5-5 keV) Spectrum

NASA Astrophysics Data System (ADS)

Caspi, Amir; Woods, Thomas N.; Stone, Jordan

2013-03-01

The solar corona is the brightest source of X-rays in the solar system, and the X-ray emission is highly variable with solar activity. While this is particularly true during solar flares, when emission can be enhanced by many orders of magnitude up to gamma-ray energies, even the so-called "quiet Sun" is bright in soft X-rays (SXRs), as the 1-2 MK ambient plasma of the corona emits significant thermal bremsstrahlung up to 5 keV. However, the actual solar SXR (0.5-5 keV) spectrum is not well known, particularly during quiet periods, as, with few exceptions, this energy range has not been systematically studied in many years. Previous observations include ultra-high-resolution but very narrow-band spectra from crystral spectrometers (e.g. Yohkoh/BCS), or integrated broadband irradiances from photometers (e.g. GOES/XRS, TIMED/XPS, etc.) that lack detailed spectral information. In recent years, broadband measurements with fair energy resolution ( 0.5-0.7 keV FWHM) were made by SphinX on CORONAS-Photon and XRS on MESSENGER, although they did not extend below 1 keV. We present observations of the quiet Sun SXR emission obtained using a new SXR spectrometer flown on the third SDO/EVE underflight calibration rocket (NASA 36.286). The commercial off-the-shelf Amptek X123 silicon drift detector, with an 8-micron Be window and custom aperture, measured the solar SXR emission from 0.5 to >10 keV with 0.15 keV FWHM resolution (though, due to hardware limitations, with only 0.12 keV binning) and 2-sec cadence over 5 minutes on 23 June 2012. Despite the rising solar cycle, activity on 23 June 2012 was abnormally low, with no visible active regions and GOES XRS emission near 2010 levels; we measured no solar counts above 4 keV during the observation period. We compare our X123 measurements with spectra and broadband irradiances from other instruments, including the SphinX observations during the deep solar minimum of 2009, and with upper limits of >3 keV quiet Sun emission
Extensive Broadband X-Ray Monitoring During the Formation of a Giant Radio Jet Base in Cyg X-3 with AstroSat

NASA Astrophysics Data System (ADS)

Pahari, Mayukh; Yadav, J. S.; Verdhan Chauhan, Jai; Rawat, Divya; Misra, Ranjeev; Agrawal, P. C.; Chandra, Sunil; Bagri, Kalyani; Jain, Pankaj; Manchanda, R. K.; Chitnis, Varsha; Bhattacharyya, Sudip

2018-01-01

We present X-ray spectral and timing behavior of Cyg X-3 as observed by AstroSat during the onset of a giant radio flare on 2017 April 1–2. Within a timescale of a few hours, the source shows a transition from the hypersoft state (HPS) to a more luminous state (we termed as the very high state), which coincides with the time of the steep rise in radio flux density by an order of magnitude. Modeling the Soft X-ray Telescope (SXT) and Large Area X-ray Proportional Counter (LAXPC) spectra jointly in 0.5–70.0 keV, we found that the first few hours of the observation is dominated by the HPS with no significant counts above 17 keV. Later, an additional flat power-law component suddenly appeared in the spectra that extends to very high energies with the power-law photon index of {1.49}-0.03+0.04. Such a flat power-law component has never been reported from Cyg X-3. Interestingly the fitted power-law model in 25–70 keV, when extrapolated to the radio frequency, predicts the radio flux density to be consistent with the trend measured from the RATAN-600 telescope at 11.2 GHz. This provides direct evidence of the synchrotron origin of flat X-ray power-law component and the most extensive monitoring of the broadband X-ray behavior at the moment of decoupling the giant radio jet base from the compact object in Cyg X-3. Using SXT and LAXPC observations, we determine the giant flare ejection time as MJD 57845.34 ± 0.08 when 11.2 GHz radio flux density increases from ∼100 to ∼478 mJy.
Fracture characteristics of balloon films

NASA Technical Reports Server (NTRS)

Portanova, Marc A.

1989-01-01

An attempt was made to determine the failure modes of high altitude scientific balloons through an investigation of the fracture characteristics of the thin polyethylene films. Two films were the subject of the evaluation, Winzen Int.'s Stratafilm SF-85 and Raven Industries' Astro-E. Research began with an investigation of the film's cold brittleness point and it's effect on the ultimate strength and elasticity of the polyethylene film. A series of preliminary investigations were conducted to develop an understanding of the material characteristics. The primary focus of this investigation was on the notch sensitivity of the films. Simple stress strain tests were also conducted to enable analysis employing fracture toughness parameters. Studies were conducted on both film types at 23 C (room temperature), -60 C, -90 C, and -120 C.

Detection of High Velocity Absorption Components in the He I Lines of Eta Carinae near the Time of Periastron

NASA Technical Reports Server (NTRS)

Richardson, Noel D.; St-Jean, Lucas; Gull, Theodore R.; Madura, Thomas; Hillier, D. John; Teodoro, Mairan; Moffat, Anthony; Corcoran, Michael; Damineli, Augusto

2014-01-01

We have obtained a total of 58 high spectral resolution (R90,000) spectra of the massive binary star eta Carinae since 2012 in an effort to continue our orbital and long-term echelle monitoring of this extreme binary (Richardson et al. 2010, AJ, 139, 1534) with the CHIRON spectrograph on the CTIO 1.5 m telescope (Tokovinin et al. 2013, PASP, 125, 1336) in the 45507500A region. We have increased our monitoring efforts and observation frequency as the periastron event of 2014 has approached. We note that there were multiple epochs this year where we observe unusual absorption components in the P Cygni troughs of the He I triplet lines. In particular, we note high velocity absorption components related to the following epochs for the following lines: He I 4713: HJD 2456754- 2456795 (velocity -450 to -560 kms) He I 5876: HJD 2456791- 2456819 (velocity -690 to -800 kms) He I 7065: HJD 2456791- 2456810 (velocity -665 to -730 kms) Figures: Note that red indicates a high-velocity component noted above. He I 4713: http:www.astro.umontreal.carichardson4713.png He I 5876: http:www.astro.umontreal.carichardson5876.png He I 7065: http:www.astro.umontreal.carichardson7065.png These absorptions are likely related to the wind-wind collision region and bow shock, as suggested by the high-velocity absorption observed by Groh et al. (2010, AA, 519, 9) in the He I 10830 Atransition. In these cases, we suspect that we look along an arm of the shock cone and that we will see a fast absorption change from the other collision region shortly after periastron. We suspect that this is related to the multiple-components of the He II 4686 line that was noted by Walter (ATel6334), and is confirmed in our data. Further, high spectral resolution data are highly encouraged,especially for resolving powers greater than 50,000.These observations were obtained with the CTIO 1.5 m telescope, operated by the SMARTS Consortium, and were obtained through both SMARTS and NOAO programs 2012A-0216,2012B-0194
Point Spread Function of ASTRO-H Soft X-Ray Telescope (SXT)

NASA Technical Reports Server (NTRS)

Hayashi, Takayuki; Sato, Toshiki; Kikuchi, Naomichi; Iizuka, Ryo; Maeda, Yoshitomo; Ishida, Manabu; Kurashima, Sho; Nakaniwa, Nozomi; Okajima, Takashi; Mori, Hideyuki;

2016-01-01

ASTRO-H (Hitomi) satellite equips two Soft X-ray Telescopes (SXTs), one of which (SXT-S) is coupled to Soft-X-ray Spectrometer (SXS) while the other (SXT-I) is coupled to Soft X-ray Imager (SXI). Although SXTs are lightweight of approximately 42 kgmodule1 and have large on-axis effective area (EA) of approximately 450 cm(exp 2) at 4.5 keV module(sub 1) by themselves, their angular resolutions are moderate approximately 1.2 arcmin in half power diameter. The amount of contamination into the SXS FOV (3.05 times 3.05 arcmin(exp 2) from nearby sources was measured in the ground-based calibration at the beamline in Institute of Space and Astronautical Science. The contamination at 4.5 keV were measured with sources distant from the SXS center by one width of the FOV in perpendicular and diagonal directions, that is, 3 and 4.5 arcmin-off, respectively. The average EA of the contamination in the four directions with the 3 and 4.5 arcmin-off were measured to be 2 and 0.6% of the on-axis EA of 412 cm (exp) for the SXS FOV, respectively. The contamination from a source distant by two FOV widths in a diagonal direction, that is, 8.6 arcmin-off was measured to be 0.1% of the on-axis at 4.5 keV. The contamination amounts were also measured at 1.5 keV and 8.0 keV which indicated that the ratio of the contamination EA to that of on-axis hardly depended on the source energy. The off-axis SXT-I images from 4.5 to 27 arcmin were acquired at intervals of -4.5 arcmin for the SXI FOV of 38 times 38 arcmin(exp 2). The image shrinked as the off-axis angle increased. Above 13.5 arcmin of off-angle, a stray appeared around the image center in the off-axis direction. As for the on-axis image, a ring-shaped stray appeared at the edge of SXI of approximately 18 arcmin distant from the image center.

Spacelab

NASA Image and Video Library

1990-12-05

This image shows a part of the Cygnus loop supernova remnant, taken by the Ultraviolet Imaging Telescope (UIT) on the Astro Observatory during the Astro-1 mission (STS-35) on December 5, 1990. Pictured is a portion of the huge Cygnus loop, an array of interstellar gas clouds that have been blasted by a 900,000 mile per hour shock wave from a prehistoric stellar explosion, which occurred about 20,000 years ago, known as supernova. With ultraviolet and x-rays, astronomers can see emissions from extremely hot gases, intense magnetic fields, and other high-energy phenomena that more faintly appear in visible and infrared light or in radio waves that are crucial to deepening the understanding of the universe. The Astro Observatory was designed to explore the universe by observing and measuring the ultraviolet radiation from celestial objects. Three instruments make up the Astro Observatory: The Hopkins Ultraviolet Telescope (HUT), the Ultraviolet Imaging Telescope (UIT), and the Wisconsin Ultraviolet Photo-Polarimetry Experiment (WUPPE). The Marshall Space Flight Center had managment responsibilities for the Astro-1 mission. The Astro-1 Observatory was launched aboard the Space Shuttle Orbiter Columbia (STS-35) on December 2, 1990.
Applications of ANSYS/Multiphysics at NASA/Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

Loughlin, Jim

2007-01-01

This viewgraph presentation reviews some of the uses that the ANSYS/Multiphysics system is used for at the NASA Goddard Space Flight Center. Some of the uses of the ANSYS system is used for is MEMS Structural Analysis of Micro-mirror Array for the James Web Space Telescope (JWST), Micro-shutter Array for JWST, MEMS FP Tunable Filter, AstroE2 Micro-calorimeter. Various views of these projects are shown in this presentation.
Cosmology, Clusters and Calorimeters

NASA Technical Reports Server (NTRS)

Figueroa-Feliciano, Enectali

2005-01-01

I will review the current state of Cosmology with Clusters and discuss the application of microcalorimeter arrays to this field. With the launch of Astro-E2 this summer and a slew of new missions being developed, microcalorimeters are the next big thing in x-ray astronomy. I will cover the basics and not-so-basic concepts of microcalorimeter designs and look at the future to see where this technology will go.
Open high-level data formats and software for gamma-ray astronomy

NASA Astrophysics Data System (ADS)

Deil, Christoph; Boisson, Catherine; Kosack, Karl; Perkins, Jeremy; King, Johannes; Eger, Peter; Mayer, Michael; Wood, Matthew; Zabalza, Victor; Knödlseder, Jürgen; Hassan, Tarek; Mohrmann, Lars; Ziegler, Alexander; Khelifi, Bruno; Dorner, Daniela; Maier, Gernot; Pedaletti, Giovanna; Rosado, Jaime; Contreras, José Luis; Lefaucheur, Julien; Brügge, Kai; Servillat, Mathieu; Terrier, Régis; Walter, Roland; Lombardi, Saverio

2017-01-01

In gamma-ray astronomy, a variety of data formats and proprietary software have been traditionally used, often developed for one specific mission or experiment. Especially for ground-based imaging atmospheric Cherenkov telescopes (IACTs), data and software are mostly private to the collaborations operating the telescopes. However, there is a general movement in science towards the use of open data and software. In addition, the next-generation IACT instrument, the Cherenkov Telescope Array (CTA), will be operated as an open observatory. We have created a Github organisation at https://github.com/open-gamma-ray-astro where we are developing high-level data format specifications. A public mailing list was set up at https://lists.nasa.gov/mailman/listinfo/open-gamma-ray-astro and a first face-to-face meeting on the IACT high-level data model and formats took place in April 2016 in Meudon (France). This open multi-mission effort will help to accelerate the development of open data formats and open-source software for gamma-ray astronomy, leading to synergies in the development of analysis codes and eventually better scientific results (reproducible, multi-mission). This write-up presents this effort for the first time, explaining the motivation and context, the available resources and process we use, as well as the status and planned next steps for the data format specifications. We hope that it will stimulate feedback and future contributions from the gamma-ray astronomy community.
Annual Report Number 3, 1986.

DTIC Science & Technology

1986-01-01

REPORT 1986 as DISTPJUtIoN STATE’Tr A Agpprovod for public reI~laeC D is riL u ti o ’ Uni e L h i DIRECTORATE SJUN 109 OF D MANAGEMENT SCIENCES AFLC/XRS...21 2. Incorporate Aircraft Availability Into D041 . 22 3. Weapon System Phase In/Out And The Aircraft Availability Procurement Model (AAPM...Capabilities .. ......... 43 2. Evaluation Of CONUS Cargo Movement Requirements ........ ................. 4 3. Material Management Manpower Standars . 4.....44 V
E-Cigarettes and "Dripping" Among High-School Youth.

PubMed

Krishnan-Sarin, Suchitra; Morean, Meghan; Kong, Grace; Bold, Krysten W; Camenga, Deepa R; Cavallo, Dana A; Simon, Patricia; Wu, Ran

2017-03-01

Electronic cigarettes (e-cigarettes) electrically heat and vaporize e-liquids to produce inhalable vapors. These devices are being used to inhale vapors produced by dripping e-liquids directly onto heated atomizers. The current study conducts the first evaluation of the prevalence rates and reasons for using e-cigarettes for dripping among high school students. In the spring of 2015, students from 8 Connecticut high schools ( n = 7045) completed anonymous surveys that examined tobacco use behaviors and perceptions. We assessed prevalence rates of ever using e-cigarettes for dripping, reasons for dripping, and predictors of dripping behaviors among those who reported ever use of e-cigarettes. Among 1080 ever e-cigarette users, 26.1% of students reported ever using e-cigarettes for dripping. Reasons for dripping included produced thicker clouds of vapor (63.5%), made flavors taste better (38.7%), produced a stronger throat hit (27.7%), curiosity (21.6%), and other (7.5%). Logistic regression analyses indicated that male adolescents (odds ratio [OR] = 1.64), whites (OR = 1.46), and those who had tried multiple tobacco products (OR = 1.34) and had greater past-month e-cigarette use frequency (OR = 1.07) were more likely to use dripping ( P s < .05). These findings indicate that a substantial portion (∼1 in 4) of high school adolescents who had ever used e-cigarettes also report using the device for dripping. Future efforts must examine the progression and toxicity of the use of e-cigarettes for dripping among youth and educate them about the potential dangers of these behaviors. Copyright © 2017 by the American Academy of Pediatrics.
Design, implementation, and performance of the Astro-H soft x-ray spectrometer aperture assembly and blocking filters

NASA Astrophysics Data System (ADS)

Kilbourne, Caroline A.; Adams, Joseph S.; Arsenovic, Petar; Ayers, Travis; Chiao, Meng P.; DiPirro, Michael J.; Eckart, Megan E.; Fujimoto, Ryuichi; Kazeva, John D.; Kripps, Kari L.; Lairson, Bruce M.; Leutenegger, Maurice A.; Lopez, Heidi C.; McCammon, Dan; McGuinness, Daniel S.; Mitsuda, Kazuhisa; Moseley, Samuel J.; Porter, F. Scott; Schweiss, Andrea N.; Takei, Yoh; Thorpe, Rosemary Schmidt; Watanabe, Tomomi; Yamasaki, Noriko Y.; Yoshida, Seiji

2018-01-01

The calorimeter array of the JAXA Astro-H (renamed Hitomi) soft x-ray spectrometer (SXS) was designed to provide unprecedented spectral resolution of spatially extended cosmic x-ray sources and of all cosmic x-ray sources in the Fe-K band around 6 keV. The properties that made the SXS array a powerful x-ray spectrometer also made it sensitive to photons from the entire electromagnetic band as well as particles. If characterized as a bolometer, it would have had a noise equivalent power of <4 × 10 ? 18 W / (Hz)0.5. Thus, it was imperative to shield the detector from thermal radiation from the instrument and optical and UV photons from the sky. In addition, it was necessary to shield the coldest stages of the instrument from the thermal radiation emanating from the warmer stages. These needs were addressed by a series of five thin-film radiation-blocking filters, anchored to the nested temperature stages, that blocked long-wavelength radiation while minimizing x-ray attenuation. The aperture assembly was a system of barriers, baffles, filter carriers, and filter mounts that supported the filters and inhibited their potential contamination. The three outer filters also had been equipped with thermometers and heaters for decontamination. We present the requirements, design, implementation, and performance of the SXS aperture assembly and blocking filters.
Spin and chirality effects in antler-topology processes at high energy $$\\varvec{e^+e^-}$$ e + e - colliders

DOE PAGES

Choi, S. Y.; Christensen, N. D.; Salmon, D.; ...

2015-10-01

We perform a model-independent investigation of spin and chirality correlation effects in the antler-topology processes e+e−→P+P−→(ℓ+D0)(ℓ−D¯0) at high-energy e+e− colliders with polarized beams. Generally the production process e+e−→P+P− can occur not only through the s-channel exchange of vector bosons, V0 , including the neutral Standard Model (SM) gauge bosons, γ and Z, but also through the s- and t-channel exchanges of new neutral states, S0 and T0 , and the u-channel exchange of new doubly charged states, U−− . The general set of (non-chiral) three-point couplings of the new particles and leptons allowed in a renormalizable quantum field theory ismore » considered. The general spin and chirality analysis is based on the threshold behavior of the excitation curves for P+P− pair production in e+e− collisions with longitudinal- and transverse-polarized beams, the angular distributions in the production process and also the production-decay angular correlations. In the first step, we present the observables in the helicity formalism. Subsequently, we show how a set of observables can be designed for determining the spins and chiral structures of the new particles without any model assumptions. Finally, taking into account a typical set of approximately chiral invariant scenarios, we demonstrate how the spin and chirality effects can be probed experimentally at a high-energy e+e− collider.« less
The Functions of BRCA2 in Homologous Recombinational Repair

DTIC Science & Technology

2004-07-01

chromatography with hydroxyapatite , Q-Sepharose, heparin affinity and MonoQ column (Fig. 4.). We have been able to obtain about 10 mg of the purified Rad51...and DNA- PKcs (the XR -1, xrs5/6, and V3 cell lines, respectively) are highly sensitive to IR in G1 and early S phases, compared to the wild-type, but
Operating modes and cooling capabilities of the 3-stage ADR developed for the Soft-X-ray Spectrometer instrument on Astro-H

NASA Astrophysics Data System (ADS)

Shirron, Peter J.; Kimball, Mark O.; James, Bryan L.; Muench, Theodore; DiPirro, Michael J.; Letmate, Richard V.; Sampson, Michael A.; Bialas, Tom G.; Sneiderman, Gary A.; Porter, Frederick S.; Kelley, Richard L.

2016-03-01

A 3-stage adiabatic demagnetization refrigerator (ADR) (Shirron et al., 2012) is used on the Soft X-ray Spectrometer instrument (Mitsuda et al., 2010) on Astro-H (Takahashi et al., 2010) [3] to cool a 6 × 6 array of X-ray microcalorimeters to 50 mK. The ADR is supported by a cryogenic system (Fujimoto et al., 2010) consisting of a superfluid helium tank, a 4.5 K Joule-Thomson (JT) cryocooler, and additional 2-stage Stirling cryocoolers that pre-cool the JT cooler and cool radiation shields within the cryostat. The ADR is configured so that it can use either the liquid helium or the JT cryocooler as its heat sink, giving the instrument an unusual degree of tolerance for component failures or degradation in the cryogenic system. The flight detector assembly, ADR and dewar were integrated into the flight dewar in early 2014, and have since been extensively characterized and calibrated. This paper summarizes the operation and performance of the ADR in all of its operating modes.
STS-Astro: Astronomy in focus of science, technology and society and analysis about the International Year of Astronomy 2009-Brazil

NASA Astrophysics Data System (ADS)

Ferreira, Orlando Rodrigues; Voelzke, Marcos Rincon

2012-10-01

This paper focuses on Science, Technology and Society around Astronomy an approach which authors call STS-Astro. It is considered that Astronomy is beyond the limits of Science itself, since it forwards to profound reflections on the own existence, predicated on the philosophical foundation of the Universe which is based on the anthropic principle. Subsequently, it discuss about the International Year of Astronomy 2009 in Brazil and their results. In 2003, Brazil, Italy and France sent a petition to the United Nations Educational, Scientific and Cultural Organization-UNESCO to consider 2009 as the International Year of Astronomy, on the occasion of 400 years of the first telescopic observations made in 1609 by Galileo Galilei (1568-1742). The International Year of Astronomy 2009 involved more than 148 countries and 815 million people, causing an unprecedented integration in the History between areas scientific, technological and humanities. Brazil had an outstanding performance, but even after a few years, numerous data in the country are still subject to studies and analyzes. The positive impacts on various sectors of the society have become permanent and aggregate actions in many institutions as schools, Universities, Observatories, Planetariums, Science Museums and the Astronomy Club, among others.
A Broadband X-Ray Imaging Spectroscopy with High-Angular Resolution: the FORCE Mission

NASA Technical Reports Server (NTRS)

Mori, Koji; Tsuru, Takeshi Go; Nakazawac, Kazuhiro; Ueda, Yoshihiro; Okajima, Takashi; Murakami, Hiroshi; Awaki, Hisamitsu; Matsumoto, Hironori; Fukazawai, Yasushi; Tsunemi, Hiroshi;

2016-01-01

We are proposing FORCE (Focusing On Relativistic universe and Cosmic Evolution) as a future Japan-lead X-ray observatory to be launched in the mid 2020s. Hitomi (ASTRO-H) possesses a suite of sensitive instruments enabling the highest energy-resolution spectroscopy in soft X-ray band, a broadband X-ray imaging spectroscopy in soft and hard X-ray bands, and further high energy coverage up to soft gamma-ray band. FORCE is the direct successor to the broadband X-ray imaging spectroscopy aspect of Hitomi (ASTRO-H) with significantly higher angular resolution. The current design of FORCE defines energy band pass of 1-80 keV with angular resolution of <15" in half-power diameter, achieving a 10 times higher sensitivity above 10 keV compared to any previous missions with simultaneous soft X-ray coverage. Our primary scientific objective is to trace the cosmic formation history by searching for "missing black holes" in various mass-scales: "buried supermassive black holes (SMBHs)" (> 10(exp 4) Stellar Mass) residing in the center of galaxies in a cosmological distance, "intermediate-mass black holes" (10(exp 2)-(10(exp 4) Stellar Mass) acting as the possible seeds from which SMBHs grow, and "orphan stellar-mass black holes" (< 10(exp 2) Stellar Mass) without companion in our Galaxy. In addition to these missing BHs, hunting for the nature of relativistic particles at various astrophysical shocks is also in our scope, utilizing the broadband X-ray coverage with high angular-resolution. FORCE are going to open a new era in these fields. The satellite is proposed to be launched with the Epsilon vehicle that is a Japanese current solid-fuel rocket. FORCE carries three identical pairs of Super-mirror and wide-band X-ray detector. The focal length is currently planned to be 10 m. The silicon mirror with multi-layer coating is our primary choice to achieve lightweight, good angular optics. The detector is a descendant of hard X-ray imager onboard Hitomi (ASTRO-H) replacing its

A broadband x-ray imaging spectroscopy with high-angular resolution: the FORCE mission

NASA Astrophysics Data System (ADS)

Mori, Koji; Tsuru, Takeshi Go; Nakazawa, Kazuhiro; Ueda, Yoshihiro; Okajima, Takashi; Murakami, Hiroshi; Awaki, Hisamitsu; Matsumoto, Hironori; Fukazawa, Yasushi; Tsunemi, Hiroshi; Takahashi, Tadayuki; Zhang, William W.

2016-07-01

We are proposing FORCE (Focusing On Relativistic universe and Cosmic Evolution) as a future Japan-lead Xray observatory to be launched in the mid 2020s. Hitomi (ASTRO-H) possesses a suite of sensitive instruments enabling the highest energy-resolution spectroscopy in soft X-ray band, a broadband X-ray imaging spectroscopy in soft and hard X-ray bands, and further high energy coverage up to soft gamma-ray band. FORCE is the direct successor to the broadband X-ray imaging spectroscopy aspect of Hitomi (ASTRO-H) with significantly higher angular resolution. The current design of FORCE defines energy band pass of 1-80 keV with angular resolution of < 15 in half-power diameter, achieving a 10 times higher sensitivity above 10 keV compared to any previous missions with simultaneous soft X-ray coverage. Our primary scientific objective is to trace the cosmic formation history by searching for "missing black holes" in various mass-scales: "buried supermassive black holes (SMBHs)" (> 104 M⊙) residing in the center of galaxies in a cosmological distance, "intermediate-mass black holes" (102-104 M⊙) acting as the possible seeds from which SMBHs grow, and "orphan stellar-mass black holes" (< 102 M⊙) without companion in our Galaxy. In addition to these missing BHs, hunting for the nature of relativistic particles at various astrophysical shocks is also in our scope, utilizing the broadband X-ray coverage with high angular-resolution. FORCE are going to open a new era in these fields. The satellite is proposed to be launched with the Epsilon vehicle that is a Japanese current solid-fuel rocket. FORCE carries three identical pairs of Super-mirror and wide-band X-ray detector. The focal length is currently planned to be 10 m. The silicon mirror with multi-layer coating is our primary choice to achieve lightweight, good angular optics. The detector is a descendant of hard X-ray imager onboard Hitomi (ASTRO-H) replacing its silicon strip detector with SOI-CMOS silicon pixel
Microcalorimeter X-ray Detectors for Solar Physics

NASA Astrophysics Data System (ADS)

Deiker, S.; Boerner, P.; Martinez-Galarce, D.; Metcalf, T.; Rausch, A.; Shing, L.; Stern, R.; Irwin, K.; William, D.; Reintsema, C.; Ullom, J.; Cabrera, B.; Lehman, S.; Brink, P.

2005-05-01

Cryogenic X-ray microcalorimeters provide high spectral resolution over a large bandwidth. They have achieved < 3 eV resolution at 5.9 keV, and can produce this performance simultaneously from 0.25 to 10 keV. Although they operate at low (< 0.1 K) temperatures, such temperature are now easily produced. Microcalorimeters cooled by adiabatic demagnetization refrigerators have already flown on sounding rocket flights to study the soft X-ray background of the interstellar medium, and will soon be launched on the ASTRO-E II satellite. Microcalorimeters based on superconducting transition edge sensors are multiplexable and may be fabricated using standard photolithographic techniques. This makes large arrays of microcalorimeters feasible. Each pixel of such an array detects the arrival time of each photon to within < 0.01 ms. Such an instrument would offer simultaneous spatial, temporal and energy resolution, bringing a wealth of new information about solar processes. Current design and performance of microcalorimeters will be presented. Future improvements required to optimize microcalorimeters for solar physics applications will also be discussed.
Electrochemical method of controlling thiolate coverage on a conductive substrate such as gold

NASA Technical Reports Server (NTRS)

Porter, Marc D. (Inventor); Weisshaar, Duane E. (Inventor)

1998-01-01

An electrochemical method for forming a partial monomolecular layer of a predetermined extent of coverage of a thiolate of the formula, XRS--, therein R can be a linear or branched chain hydrocarbon or an aromatic or the like and X can be any compatible end group, e.g., OH, COOH, CH.sub.3 or the like, upon a substrate such as gold, which involves applying in an electrochemical system a constant voltage preselected to yield the desired predetermined extent of coverage.
Electrochemical method of controlling thiolate coverage on a conductive substrate such as gold

DOEpatents

Porter, Marc D.; Weisshaar, Duane E.

1998-10-27

An electrochemical method for forming a partial monomolecular layer of a predetermined extent of coverage of a thiolate of the formula, XRS--, therein R can be a linear or branched chain hydrocarbon or an aromatic or the like and X can be any compatible end group, e.g., OH, COOH, CH.sub.3 or the like, upon a substrate such as gold, which involves applying in an electrochemical system a constant voltage preselected to yield the desired predetermined extent of coverage.
Electrochemical method of controlling thiolate coverage on a conductive substrate such as gold

DOEpatents

Porter, Marc D.; Weisshaar, Duane E.

1997-06-03

An electrochemical method for forming a partial monomolecular layer of a predetermined extent of coverage of a thiolate of the formula, XRS.sup.-, wherein R can be a linear or branched chain hydrocarbon or an aromatic or the like and X can be any compatible end group, e.g., OH, COOH, CH.sub.3 or the like, upon a substrate such as gold, which involves applying in an electrochemical system a constant voltage preselected to yield the desired predetermined extent of coverage.
XDGMM: eXtreme Deconvolution Gaussian Mixture Modeling

NASA Astrophysics Data System (ADS)

Holoien, Thomas W.-S.; Marshall, Philip J.; Wechsler, Risa H.

2017-08-01

XDGMM uses Gaussian mixtures to do density estimation of noisy, heterogenous, and incomplete data using extreme deconvolution (XD) algorithms which is compatible with the scikit-learn machine learning methods. It implements both the astroML and Bovy et al. (2011) algorithms, and extends the BaseEstimator class from scikit-learn so that cross-validation methods work. It allows the user to produce a conditioned model if values of some parameters are known.

OPTIMIZATION OF A TWO-STAGE ADR FOR THE SOFT X-RAY SPECTROMETER (SXS) INSTRUMENT ON THE ASTRO-H MISSION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shirron, P. J.; Kimball, M. O.; Wegel, D. C.

2010-04-09

NASA/Goddard Space Flight Center has begun developing the Soft X-ray Spectrometer (SXS) instrument that will be flown on the Japanese Astro-H mission. The SXS's 36-pixel detector array will be cooled to 50 mK using a two-stage adiabatic demagnetization refrigerator (ADR). A complicating factor for its design is that the ADR will be integrated into a superfluid helium dewar at 1.3 K that will be coupled to a 1.8 K Joule-Thomson (JT) stage through a heat switch. When liquid helium is present, the coupling will be weak, and the JT stage will act primarily as a shield to reduce parasitic heatmore » loads. When the liquid is depleted, the heat switch will couple more strongly so that the ADR can continue to operate using the JT stage as its heat sink. A two-stage ADR is the most mass efficient option and it has the operational flexibility to work well with a stored cryogen and a cryocooler. The stages are operated independently, and this opens up a very large parameter space for optimizing the design. This paper discusses the optimization process and most relevant trades considered in the design of the SXS ADR, and its expected performance.« less
Science Instruments for the Advanced X-Ray Astrophysics Facility (AXAF)

NASA Technical Reports Server (NTRS)

Winkler, Carl E.; Cumings, Nesbitt P.; Randolph, Joseph L.; Talley, Drayton H.

1993-01-01

The AXAF program has undergone major changes since the Announcement of Opportunity was extended by NASA Headquarters in 1983. The Science Instruments (SI's) for AXAF have also experienced several design changes since they were competitively selected in 1985. Moreover, two separate complementary missions are now being baselined for AXAF; one is designated AXAF-I for imaging and will include the high precision Wolter type I optics, and the other is called AXAF-S for spectroscopy. The resulting less-costly AXAF will still be superior to any previous x-ray observatories. Both missions continue to be managed. AXAF-I contains two focal plane SI's, the High Resolution Camera (HRC), and the AXAF Charge-Coupled Device (CCD) imaging spectrometer (ACIS), as well as the High-Energy Transmission Grating Spectrometer (HETGS) and the Low-Energy Transmission Grating Spectrometer (LETGS). Optics/Cryogenics Division (BECD). AXAF-S features only one focal plane SI, the X-Ray Spectrometer (XRS). The grazing incidence mirrors for this mission are mainly to provide a large collecting area and to concentrate these x-ray photons onto the XRS detector. Precise focusing, although preferred, is of secondary importance. Nested conical foil mirrors are currently baselined; however, replicated imaging optics are being evaluated for collecting efficiency and cost. AXAF-S is scheduled to be launched in late 1999. It has been designated as an MSFC in-house project. In addition to overall management, MSFC is fully responsible for the design, development, integration, and test of the complete AXAF-S observatory, including the XRS which will be furnished by the Goddard Space Flight Center (GSFC). Together, AXAF-I and AXAF-S constitute the third of NASA's series of Great Observatories, joining the Hubble space telescope (HST) and the Gamma-Ray Observatory (GRO) which are already operational. The develop- ment, launch, and operation of the Space InfraRed Telescope Facility (SIRTF) will follow later to
High-Fat Diet Changes Hippocampal Apolipoprotein E (ApoE) in a Genotype- and Carbohydrate-Dependent Manner in Mice.

PubMed

Lane-Donovan, Courtney; Herz, Joachim

2016-01-01

Alzheimer's disease is a currently incurable neurodegenerative disease affecting millions of individuals worldwide. Risk factors for Alzheimer's disease include genetic risk factors, such as possession of ε4 allele of apolipoprotein E (ApoE4) over the risk-neutral ApoE3 allele, and lifestyle risk factors, such as diet and exercise. The intersection of these two sources of disease risk is not well understood. We investigated the impact of diet on ApoE levels by feeding wildtype, ApoE3, and ApoE4 targeted replacement (TR) mice with chow, high-fat, or ketogenic (high-fat, very-low-carbohydrate) diets. We found that high-fat diet affected both plasma and hippocampal levels of ApoE in an isoform-dependent manner, with high-fat diet causing a surprising reduction of hippocampal ApoE levels in ApoE3 TR mice. Conversely, the ketogenic diet had no effect on hippocampal ApoE. Our findings suggest that the use of dietary interventions to slow the progression AD should take ApoE genotype into consideration.
High-Fat Diet Changes Hippocampal Apolipoprotein E (ApoE) in a Genotype- and Carbohydrate-Dependent Manner in Mice

PubMed Central

Lane-Donovan, Courtney; Herz, Joachim

2016-01-01

Alzheimer’s disease is a currently incurable neurodegenerative disease affecting millions of individuals worldwide. Risk factors for Alzheimer’s disease include genetic risk factors, such as possession of ε4 allele of apolipoprotein E (ApoE4) over the risk-neutral ApoE3 allele, and lifestyle risk factors, such as diet and exercise. The intersection of these two sources of disease risk is not well understood. We investigated the impact of diet on ApoE levels by feeding wildtype, ApoE3, and ApoE4 targeted replacement (TR) mice with chow, high-fat, or ketogenic (high-fat, very-low-carbohydrate) diets. We found that high-fat diet affected both plasma and hippocampal levels of ApoE in an isoform-dependent manner, with high-fat diet causing a surprising reduction of hippocampal ApoE levels in ApoE3 TR mice. Conversely, the ketogenic diet had no effect on hippocampal ApoE. Our findings suggest that the use of dietary interventions to slow the progression AD should take ApoE genotype into consideration. PMID:26828652
TH-E-19A-01: Quality and Safety in Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ford, E; Ezzell, G; Miller, B

2014-06-15

Clinical radiotherapy data clearly demonstrate the link between the quality and safety of radiation treatments and the outcome for patients. The medical physicist plays an essential role in this process. To ensure the highest quality treatments, the medical physicist must understand and employ modern quality improvement techniques. This extends well beyond the duties traditionally associated with prescriptive QA measures. This session will review the current best practices for improving quality and safety in radiation therapy. General elements of quality management will be reviewed including: what makes a good quality management structure, the use of prospective risk analysis such as FMEA,more » and the use of incident learning. All of these practices are recommended in society-level documents and are incorporated into the new Practice Accreditation program developed by ASTRO. To be effective, however, these techniques must be practical in a resource-limited environment. This session will therefore focus on practical tools such as the newly-released radiation oncology incident learning system, RO-ILS, supported by AAPM and ASTRO. With these general constructs in mind, a case study will be presented of quality management in an SBRT service. An example FMEA risk assessment will be presented along with incident learning examples including root cause analysis. As the physicist's role as “quality officer” continues to evolve it will be essential to understand and employ the most effective techniques for quality improvement. This session will provide a concrete overview of the fundamentals in quality and safety. Learning Objectives: Recognize the essential elements of a good quality management system in radiotherapy. Understand the value of incident learning and the AAPM/ASTRO ROILS incident learning system. Appreciate failure mode and effects analysis as a risk assessment tool and its use in resource-limited environments. Understand the fundamental principles of
Future of ePix detectors for high repetition rate FELs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blaj, G., E-mail: blaj@slac.stanford.edu; Caragiulo, P.; Carini, G.

2016-07-27

Free-electron lasers (FELs) made the imaging of atoms and molecules in motion possible, opening new science opportunities with high brilliance, ultra-short x-ray laser pulses at up to 120 Hz. Some new or upgraded FEL facilities will operate at greatly increased pulse rates (kHz to MHz), presenting additional requirements on detection. We will present the ePix platform for x-ray detectors and the current status of the ePix detectors: ePix100 for low noise applications, ePix10k for high dynamic range applications, and ePixS for spectroscopic applications. Then we will introduce the plans to match the ePix detectors with the requirements of currently plannedmore » high repetition rate FELs (mainly readout speed and energy range).« less
High eIF4E, VEGF, and Microvessel Density in Stage I to III Breast Cancer

PubMed Central

Byrnes, Kerry; White, Stephen; Chu, Quyen; Meschonat, Carol; Yu, Herbert; Johnson, Lester W.; DeBenedetti, Arrigo; Abreo, Fleurette; Turnage, Richard H.; McDonald, John C.; Li, Benjamin D.

2006-01-01

Objective: In a prospective trial, to determine if eIF4E overexpression in breast cancer specimens is correlated with VEGF elevation, increased tumor microvessel density (MVD) counts, and a worse clinical outcome irrespective of nodal status. Summary and Background Data: In vitro, the overexpression of eukaryotic initiation factor 4E (eIF4E) up-regulates the translation of mRNAs with long 5′-untranslated regions (5′-UTRs). One such gene product is the vascular endothelial growth factor (VEGF). Methods: A total of 114 stage I to III breast cancer patients were prospectively accrued and followed with a standardized clinical surveillance protocol. Cancer specimens were quantified for eIF4E, VEGF, and MVD. Outcome endpoints were cancer recurrence and cancer-related death. Results: eIF4E overexpression was found in all cancer specimens (mean ± SD, 12.5 ± 7.6-fold). Increasing eIF4E overexpression correlated with increasing VEGF elevation (r = 0.24, P = 0.01, Spearman's coefficient), and increasing MVD counts (r = 0.35, P < 0.0002). Patients whose tumor had high eIF4E overexpression had shorter disease-free survival (P = 0.004, log-rank test) and higher cancer-related deaths (P = 0.002) than patients whose tumors had low eIF4E overexpression. Patients with high eIF4E had a hazard ratio for cancer recurrence and cancer-related death of 1.8 and 2.1 times that of patients with low eIF4E (respectively, P = 0.009 and P = 0.002, Cox proportional hazard model). Conclusions: In breast cancer patients, increasing eIF4E overexpression in the cancer specimens correlates with higher VEGF levels and MVD counts. Patients whose tumors had high eIF4E overexpression had a worse clinical outcome, independent of nodal status. Thus, eIF4E overexpression in breast cancer appears to predict increased tumor vascularity and perhaps cancer dissemination by hematogenous means. PMID:16633004
Heteromeric assembly of P2X subunits

PubMed Central

Saul, Anika; Hausmann, Ralf; Kless, Achim; Nicke, Annette

2013-01-01

Transcripts and/or proteins of P2X receptor (P2XR) subunits have been found in virtually all mammalian tissues. Generally more than one of the seven known P2X subunits have been identified in a given cell type. Six of the seven cloned P2X subunits can efficiently form functional homotrimeric ion channels in recombinant expression systems. This is in contrast to other ligand-gated ion channel families, such as the Cys-loop or glutamate receptors, where homomeric assemblies seem to represent the exception rather than the rule. P2XR mediated responses recorded from native tissues rarely match exactly the biophysical and pharmacological properties of heterologously expressed homomeric P2XRs. Heterotrimerization of P2X subunits is likely to account for this observed diversity. While the existence of heterotrimeric P2X2/3Rs and their role in physiological processes is well established, the composition of most other P2XR heteromers and/or the interplay between distinct trimeric receptor complexes in native tissues is not clear. After a description of P2XR assembly and the structure of the intersubunit ATP-binding site, this review summarizes the distribution of P2XR subunits in selected mammalian cell types and the biochemically and/or functionally characterized heteromeric P2XRs that have been observed upon heterologous co-expression of P2XR subunits. We further provide examples where the postulated heteromeric P2XRs have been suggested to occur in native tissues and an overview of the currently available pharmacological tools that have been used to discriminate between homo- and heteromeric P2XRs. PMID:24391538
Spin and chirality effects in antler-topology processes at high energy $${e^+e^-}$$ colliders

DOE PAGES

Choi, S. Y.; Christensen, N. D.; Salmon, D.; ...

2015-10-01

We perform a model-independent investigation of spin and chirality correlation effects in the antler-topology processes e +e -→P +P -→(ℓ+D0)(ℓ-D¯0) at high-energy e +e - colliders with polarized beams. Generally the production process e +e -→P +P - can occur not only through the s-channel exchange of vector bosons, V0 , including the neutral Standard Model (SM) gauge bosons, γ and Z, but also through the s- and t-channel exchanges of new neutral states, S0 and T0 , and the u-channel exchange of new doubly charged states, U-- . The general set of (non-chiral) three-point couplings of the new particlesmore » and leptons allowed in a renormalizable quantum field theory is considered. The general spin and chirality analysis is based on the threshold behavior of the excitation curves for P +P - pair production in e +e - collisions with longitudinal- and transverse-polarized beams, the angular distributions in the production process and also the production-decay angular correlations. In the first step, we present the observables in the helicity formalism. Subsequently, we show how a set of observables can be designed for determining the spins and chiral structures of the new particles without any model assumptions. Finally, taking into account a typical set of approximately chiral invariant scenarios, we demonstrate how the spin and chirality effects can be probed experimentally at a high-energy e +e - collider.« less
Spin and chirality effects in antler-topology processes at high energy $${e^+e^-}$$ colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, S. Y.; Christensen, N. D.; Salmon, D.

We perform a model-independent investigation of spin and chirality correlation effects in the antler-topology processes e +e -→P +P -→(ℓ+D0)(ℓ-D¯0) at high-energy e +e - colliders with polarized beams. Generally the production process e +e -→P +P - can occur not only through the s-channel exchange of vector bosons, V0 , including the neutral Standard Model (SM) gauge bosons, γ and Z, but also through the s- and t-channel exchanges of new neutral states, S0 and T0 , and the u-channel exchange of new doubly charged states, U-- . The general set of (non-chiral) three-point couplings of the new particlesmore » and leptons allowed in a renormalizable quantum field theory is considered. The general spin and chirality analysis is based on the threshold behavior of the excitation curves for P +P - pair production in e +e - collisions with longitudinal- and transverse-polarized beams, the angular distributions in the production process and also the production-decay angular correlations. In the first step, we present the observables in the helicity formalism. Subsequently, we show how a set of observables can be designed for determining the spins and chiral structures of the new particles without any model assumptions. Finally, taking into account a typical set of approximately chiral invariant scenarios, we demonstrate how the spin and chirality effects can be probed experimentally at a high-energy e +e - collider.« less
Electrochemical method of controlling thiolate coverage on a conductive substrate such as gold

DOEpatents

Porter, M.D.; Weisshaar, D.E.

1998-10-27

An electrochemical method is described for forming a partial monomolecular layer of a predetermined extent of coverage of a thiolate of the formula, XRS-, therein R can be a linear or branched chain hydrocarbon or an aromatic or the like and X can be any compatible end group, e.g., OH, COOH, CH{sub 3} or the like, upon a substrate such as gold, which involves applying in an electrochemical system a constant voltage preselected to yield the desired predetermined extent of coverage. 13 figs.
Science fiction and the history of the astro-department of Carl Zeiss Jena (German Title: Science Fiction und die Geschichte der Astroabteilung von Carl Zeiss Jena)

NASA Astrophysics Data System (ADS)

Beck, Hans G.

This contribution uses the literary form of science fiction in retrospect, in order to display the initial conditions given in the run-up of the founding of the astro-department of the Zeiss factory. Written minutes (supposedly found during restoration works in the people's house in Jena) introduce the participants of a sort of founding party of the main actors Ernst Abbe, Otto Schott, Siegfried Czapski, Hans Harting, Albert König, Franz Meyer and Walter Villiger. Their contributions to the discussion yield a market analysis, based on the past development of the technology of astronomical instruments, the international competitors' state of the art, and the assessment of the future development in astronomy and especially of astrophysics. The contribution presents a piece of modern history of the year 1987; it was presented as a talk on May 13 of the same year, when Rolf Riekher celebrated his 65th birthday.
eXtended CASA Line Analysis Software Suite (XCLASS)

NASA Astrophysics Data System (ADS)

Möller, T.; Endres, C.; Schilke, P.

2017-02-01

The eXtended CASA Line Analysis Software Suite (XCLASS) is a toolbox for the Common Astronomy Software Applications package (CASA) containing new functions for modeling interferometric and single dish data. Among the tools is the myXCLASS program which calculates synthetic spectra by solving the radiative transfer equation for an isothermal object in one dimension, whereas the finite source size and dust attenuation are considered as well. Molecular data required by the myXCLASS program are taken from an embedded SQLite3 database containing entries from the Cologne Database for Molecular Spectroscopy (CDMS) and JPL using the Virtual Atomic and Molecular Data Center (VAMDC) portal. Additionally, the toolbox provides an interface for the model optimizer package Modeling and Analysis Generic Interface for eXternal numerical codes (MAGIX), which helps to find the best description of observational data using myXCLASS (or another external model program), that is, finding the parameter set that most closely reproduces the data. http://www.astro.uni-koeln.de/projects/schilke/myXCLASSInterface A copy of the code is available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/598/A7
The Si/CdTe semiconductor camera of the ASTRO-H Hard X-ray Imager (HXI)

NASA Astrophysics Data System (ADS)

Sato, Goro; Hagino, Kouichi; Watanabe, Shin; Genba, Kei; Harayama, Atsushi; Kanematsu, Hironori; Kataoka, Jun; Katsuragawa, Miho; Kawaharada, Madoka; Kobayashi, Shogo; Kokubun, Motohide; Kuroda, Yoshikatsu; Makishima, Kazuo; Masukawa, Kazunori; Mimura, Taketo; Miyake, Katsuma; Murakami, Hiroaki; Nakano, Toshio; Nakazawa, Kazuhiro; Noda, Hirofumi; Odaka, Hirokazu; Onishi, Mitsunobu; Saito, Shinya; Sato, Rie; Sato, Tamotsu; Tajima, Hiroyasu; Takahashi, Hiromitsu; Takahashi, Tadayuki; Takeda, Shin`ichiro; Yuasa, Takayuki

2016-09-01

The Hard X-ray Imager (HXI) is one of the instruments onboard the ASTRO-H mission [1-4] to be launched in early 2016. The HXI is the focal plane detector of the hard X-ray reflecting telescope that covers an energy range from 5 to 80 keV. It will execute observations of astronomical objects with a sensitivity for point sources as faint as 1/100,000 of the Crab nebula at > 10 keV. The HXI camera - the imaging part of the HXI - is realized by a hybrid semiconductor detector system that consists of silicon (Si) and cadmium telluride (CdTe) semiconductor detectors. Here, we present the final design of the HXI camera and report on the development of the flight model. The camera is composed of four layers of Double-sided Silicon Strip Detectors (DSSDs) and one layer of CdTe Double-sided Strip Detector (CdTe-DSD), each with an imaging area of 32 mm×32 mm. The strip pitch of the Si and CdTe sensors is 250 μm, and the signals from all 1280 strips are processed by 40 Application Specified Integrated Circuits (ASICs) developed for the HXI. The five layers of sensors are vertically stacked with a 4 mm spacing to increase the detection efficiency. The thickness of the sensors is 0.5 mm for the Si, and 0.75 mm for the CdTe. In this configuration, soft X-ray photons will be absorbed in the Si part, while hard X-ray photons will go through the Si part and will be detected in the CdTe part. The design of the sensor trays, peripheral circuits, power connections, and readout schemes are also described. The flight models of the HXI camera have been manufactured, tested and installed in the HXI instrument and then on the satellite.
Modeling the spectral response for the soft X-ray imager onboard the ASTRO-H satellite

NASA Astrophysics Data System (ADS)

Inoue, Shota; Hayashida, Kiyoshi; Katada, Shuhei; Nakajima, Hiroshi; Nagino, Ryo; Anabuki, Naohisa; Tsunemi, Hiroshi; Tsuru, Takeshi Go; Tanaka, Takaaki; Uchida, Hiroyuki; Nobukawa, Masayoshi; Nobukawa, Kumiko Kawabata; Washino, Ryosaku; Mori, Koji; Isoda, Eri; Sakata, Miho; Kohmura, Takayoshi; Tamasawa, Koki; Tanno, Shoma; Yoshino, Yuma; Konno, Takahiro; Ueda, Shutaro; ASTRO-H/SXI Team

2016-09-01

The ASTRO-H satellite is the 6th Japanese X-ray astronomical observatory to be launched in early 2016. The satellite carries four kinds of detectors, and one of them is an X-ray CCD camera, the soft X-ray imager (SXI), installed on the focal plane of an X-ray telescope. The SXI contains four CCD chips, each with an imaging area of 31 mm × 31 mm , arrayed in mosaic, covering the field-of-view of 38‧ ×38‧ , the widest ever flown in orbit. The CCDs are a P-channel back-illuminated (BI) type with a depletion layer thickness of 200 μ m . We operate the CCDs in a photon counting mode in which the position and energy of each photon are measured in the energy band of 0.4-12 keV. To evaluate the X-ray spectra obtained with the SXI, an accurate calibration of its response function is essential. For this purpose, we performed calibration experiments at Kyoto and Photon Factory of KEK, each with different X-ray sources with various X-ray energies. We fit the obtained spectra with 5 components; primary peak, secondary peak, constant tail, Si escape and Si fluorescence, and then model their energy dependence using physics-based or empirical formulae. Since this is the first adoption of P-channel BI-type CCDs on an X-ray astronomical satellite, we need to take special care on the constant tail component which is originated in partial charge collection. It is found that we need to assume a trapping layer at the incident surface of the CCD and implement it in the response model. In addition, the Si fluorescence component of the SXI response is significantly weak, compared with those of front-illuminated type CCDs.
DOE Office of Scientific and Technical Information (OSTI.GOV)

De Geronimo, G.; Fried, J.; Rehak, P.

We present an application-specific integrated circuit (ASIC) for high-resolution x-ray spectrometers (XRS). The ASIC reads out signals from pixelated silicon drift detectors (SDDs). The pixel does not have an integrated field effect transistor (FET); rather, readout is accomplished by wire-bonding the anodes to the inputs of the ASIC. The ASIC dissipates 32 mW, and offers 16 channels of low-noise charge amplification, high-order shaping with baseline stabilization, discrimination, a novel pile-up rejector, and peak detection with an analog memory. The readout is sparse and based on custom low-power tristatable low-voltage differential signaling (LPT-LVDS). A unit of 64 SDD pixels, read outmore » by four ASICs, covers an area of 12.8 cm{sup 2} and dissipates with the sensor biased about 15 mW/cm{sup 2}. As a tile-based system, the 64-pixel units cover a large detection area. Our preliminary measurements at -44 C show a FWHM of 145 eV at the 5.9 keV peak of a {sup 55}Fe source, and less than 80 eV on a test-pulse line at 200 eV.« less
The evaluation of the Hitomi (Astro-H)/SXS spare beryllium window in 3.8-30 keV

NASA Astrophysics Data System (ADS)

Hoshino, Akio; Yoshida, Yuki; Kitamoto, Shunji; Fujimoto, Ryuichi; Yamasaki, Noriko Y.; Ina, Toshiaki; Uruga, Tomoya; Eckart, Megan; Leutenegger, Maurice

2017-08-01

During the Hitomi (Astro-H) commissioning observations the SXS dewar gate valve (GV) remained closed to protect the instrument from initial spacecraft outgassing. As a result, the optical path of the observations included the Be window installed on the GV. Both x-ray fluorescence (XRF) analysis and x-ray transmission measurements were performed in June 2016 on the flight-spare Be window which is the same lot as the flight material at SPring-8 in Japan. The beamline operating range is 3.8 - 30 keV. We used a beam spot size of 1 mm × 0.2 mm to measure two positions on the Be window, at the center of the window and at one position 6.5 mm off-center. We used simultaneous transmission measurements of standard materials for energy calibration. The transmission data clearly showed Fe and Ni K-edges, plus a marginal detection of the Mn K-edge. We found that our transmission data was best fit using the following component Be: 261.86+/-0.01μm, Cr: 3nm (fixed), Mn: 3.81+/-0.05nm, Fe: 10.83+/-0.05nm, Ni: 16.48+/-0.03nm, Cu: 5nm (fixed). The transmission is reduced 1% at the Fe K-edge. The amount of contaminated materials are comparable to the values of the value provided by the vender. The surface transmission is strained with σ = 0.11% of the unbiased standard deviation calculated variation in the residuals between the measured value and the model.
STS-67 crew insignia

NASA Technical Reports Server (NTRS)

1995-01-01

Observation and remote exploration of the Universe in the ultraviolet wavelengths of light are the focus of the STS-67/ASTRO-2 mission, as depicted in the crew patch designed by the crew members. The insignia shows the ASTRO-2 telescopes in the Space Shuttle Endeavour's payload bay, orbiting high above Earth's atmosphere. The three sets of rays, diverging from the telescope on the patch atop the Instrument Pointing System (IPS), correspond to the three ASTRO-2 telescopes - the Hopkins Ultraviolet Telescope (HUT), The Ultraviolet Imaging Telescope (UIT), and the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE). The telescopes are coaligned to simultaneously view the same astronomical object, as shown by the convergence of rays on the NASA symbol. This symbol also represents the excellence of the union of the NASA teams and the universality's in the exploration of the universe through astronomy. The celestial targets of ASTRO-2 include the observation of planets, stars and gala
Impulse oscillometry at preschool age is a strong predictor of lung function by flow-volume spirometry in adolescence.

PubMed

Lauhkonen, Eero; Riikonen, Riikka; Törmänen, Sari; Koponen, Petri; Nuolivirta, Kirsi; Helminen, Merja; Toikka, Jyri; Korppi, Matti

2018-05-01

The transition from early childhood wheezing to persistent asthma is linked to lung function impairment over time. Little is known how the methods used to study lung function at different ages correlate longitudinally. Sixty-four children with a history of hospitalization for bronchiolitis before 6 months of age were prospectively studied with impulse oscillometry (IOS) at the mean age of 6.3 years and these preschool IOS results were compared with flow-volume spirometry (FVS) measurements at mean age of 11.4 years. The baseline respiratory system resistance at 5 Hz (Rrs5) showed a modest statistically significant correlation with all baseline FVS parameters except FVC. The post-bronchodilator (post-BD) Rrs5 showed a modest statistically significant correlation with post-BD FEV 1 and FEV 1 /FVC. The bronchodilator-induced decrease in Rrs5 showed a modest statistically significant correlation with the percent increase in FEV 1 . Baseline and post-BD respiratory reactance at 5 Hz (Xrs5) showed a modest statistically significant correlation with baseline and post-BD FVS parameters except post-BD FEV 1 /FVC, respectively, and post-BD Xrs5 showed a strong correlation with post-BD FVC (ρ = 0.61) and post-BD FEV 1 (ρ = 0.59). In adjusted linear regression, preschool Xrs5 remained as a statistically significant independent predictor of FVS parameters in adolescence; the one-unit decrease in the Z-score of preschool post-BD Xrs5 predicted 9.6% lower post-BD FEV 1 , 9.3% lower post-BD FVC, and 9.7% lower post-BD MEF 50 when expressed as %-predicted parameters. Persistent post-BD small airway impairment in children with a history of bronchiolitis detected with IOS at preschool age predicted FVS results measured in early adolescence. © 2018 Wiley Periodicals, Inc.
Astro-WISE: Chaining to the Universe

NASA Astrophysics Data System (ADS)

Valentijn, E. A.; McFarland, J. P.; Snigula, J.; Begeman, K. G.; Boxhoorn, D. R.; Rengelink, R.; Helmich, E.; Heraudeau, P.; Verdoes Kleijn, G.; Vermeij, R.; Vriend, W.-J.; Tempelaar, M. J.; Deul, E.; Kuijken, K.; Capaccioli, M.; Silvotti, R.; Bender, R.; Neeser, M.; Saglia, R.; Bertin, E.; Mellier, Y.

2007-10-01

The recent explosion of recorded digital data and its processed derivatives threatens to overwhelm researchers when analysing their experimental data or looking up data items in archives and file systems. While current hardware developments allow the acquisition, processing and storage of hundreds of terabytes of data at the cost of a modern sports car, the software systems to handle these data are lagging behind. This problem is very general and is well recognized by various scientific communities; several large projects have been initiated, e.g., DATAGRID/EGEE {http://www.eu-egee.org/} federates compute and storage power over the high-energy physical community, while the international astronomical community is building an Internet geared Virtual Observatory {http://www.euro-vo.org/pub/} (Padovani 2006) connecting archival data. These large projects either focus on a specific distribution aspect or aim to connect many sub-communities and have a relatively long trajectory for setting standards and a common layer. Here, we report first light of a very different solution (Valentijn & Kuijken 2004) to the problem initiated by a smaller astronomical IT community. It provides an abstract scientific information layer which integrates distributed scientific analysis with distributed processing and federated archiving and publishing. By designing new abstractions and mixing in old ones, a Science Information System with fully scalable cornerstones has been achieved, transforming data systems into knowledge systems. This break-through is facilitated by the full end-to-end linking of all dependent data items, which allows full backward chaining from the observer/researcher to the experiment. Key is the notion that information is intrinsic in nature and thus is the data acquired by a scientific experiment. The new abstraction is that software systems guide the user to that intrinsic information by forcing full backward and forward chaining in the data modelling.

The crystalline revolution :ISO's finding opens a new research field, "astro-mineralogy"

NASA Astrophysics Data System (ADS)

2000-02-01

Silicate minerals were known to be a main component of dust in space, but detecting them in a crystallised state has been a surprise. It allows the identification of precise silicates in astronomical objects, which will open "a totally new field in astronomy: astro-mineralogy. This is the crystalline revolution", said the author, Dutch astronomer Rens Waters of Amsterdam university. "It's really fantastic, this possibility of identifying the silicates. Before ISO everybody thought that all silicates in space were amorphous, without a well-ordered internal structure; that means you cannot differentiate among the many different silicates existing. Now we can try to identify them and track their presence in different regions. A whole new research field is starting", said Rens Waters, who brought to the press conference samples of several terrestrial crystalline silicates: olivine and pyroxene, the most common silicates on Earth. Crystals give key clues about the physical conditions and evolutionary history of crystal-bearing objects. The precise mechanisms for crystal-making are now being researched now very actively in the laboratories, although some working-hypotheses are already being used. For instance, crystals can be made by heating the material to temperatures above 1 300 degrees Centigrade and then cooling it down slowly. Those found so far by ISO are at -170 degrees Centigrade, both in stellar envelopes and in protoplanetary discs. In the case of the old stars -red giant stars, where crystals are found to account for as much as 20% of all the surrounding dust, astronomers think that that the high temperatures near the star triggered the crystallisation of the silicates. In the protoplanetary discs some experts postulate that electric shocks - like lightning flashes - heated the dust, which cooled afterwards. "The crystals detected by ISO in these discs have a size of about a thousandth of a millimetre. They collide with each other, forming bigger and bigger
Camões e a cosmogonia

NASA Astrophysics Data System (ADS)

Costa, J. M.

2003-08-01

Os Lusíadas, escrito por Luis de Camões em 1572, é um poema épico renascentista e a visão Cosmogônica do autor é apresentada, principalmente, no último canto do poema, quando Tétis mostra ao Gama a Máquina do Mundo. A Cosmogonia de Camões neste poema reflete uma visão de uma época de transição, que ainda não incorporou os elementos da revolução Copernicana. É uma visão Grego- Ptolomaica e também medieval. O poeta guia-se pela tradução e notas feita por Pedro Nunes, inventor do Nonio, do Tratado da Esfera "De Sphaera" do Astrônomo Inglês John Holywood, mais conhecido pelo nome latinizado de Johannes Sacrobosco. Outra provável fonte de Camões, de acordo com Luciano Antonio Pereira da Silva em Astronomia de os Lusíadas, é o "Theoricae novae Planetarum" (1460) do astrólogo Alemão Jorge Purbáquio (1423 - 1461). A Astronomia de Os Lusíadas representa a ciência do tempo de Camões. Camões nunca emprega a palavra constelação e seu catálogo é bastante completo. A Máquina do Mundo tem a Terra no centro. Em redor, em círculos concêntricos, a lua (Diana), Mercúrio, Vênus, o Sol (Febo), Marte, Júpiter e Saturno. Envolvendo estes astros tem o firmamento seguido pelo "Céu Áqueo" ou cristalino, depois o 1o Móbil, esfera que arrasta todas as outras consigo. Este trabalho, multidisciplinar, serve tanto para ensinar aos alunos da Física como das Ciências Humanas, a concepção de mundo do renascimento de uma forma belamente poética em versos decassílabos Este trabalho também ajuda na apreciação do maior clássico da língua portuguesa e mostra como as Ciências e as artes, em geral, estão correlacionadas e refletem a visão de mundo da época em que foi produzida.
Activation and Regulation of Purinergic P2X Receptor Channels

PubMed Central

Coddou, Claudio; Yan, Zonghe; Obsil, Tomas; Huidobro-Toro, J. Pablo

2011-01-01

Mammalian ATP-gated nonselective cation channels (P2XRs) can be composed of seven possible subunits, denoted P2X1 to P2X7. Each subunit contains a large ectodomain, two transmembrane domains, and intracellular N and C termini. Functional P2XRs are organized as homomeric and heteromeric trimers. This review focuses on the binding sites involved in the activation (orthosteric) and regulation (allosteric) of P2XRs. The ectodomains contain three ATP binding sites, presumably located between neighboring subunits and formed by highly conserved residues. The detection and coordination of three ATP phosphate residues by positively charged amino acids are likely to play a dominant role in determining agonist potency, whereas an AsnPheArg motif may contribute to binding by coordinating the adenine ring. Nonconserved ectodomain histidines provide the binding sites for trace metals, divalent cations, and protons. The transmembrane domains account not only for the formation of the channel pore but also for the binding of ivermectin (a specific P2X4R allosteric regulator) and alcohols. The N- and C- domains provide the structures that determine the kinetics of receptor desensitization and/or pore dilation and are critical for the regulation of receptor functions by intracellular messengers, kinases, reactive oxygen species and mercury. The recent publication of the crystal structure of the zebrafish P2X4.1R in a closed state provides a major advance in the understanding of this family of receptor channels. We will discuss data obtained from numerous site-directed mutagenesis experiments accumulated during the last 15 years with reference to the crystal structure, allowing a structural interpretation of the molecular basis of orthosteric and allosteric ligand actions. PMID:21737531
The immediate effects of a single autogenic drainage session on ventilatory mechanics in adult subjects with cystic fibrosis

PubMed Central

Wallaert, Elliot; Perez, Thierry; Prevotat, Anne; Reychler, Gregory; Le Rouzic, Olivier

2018-01-01

Introduction The aim of this study was to gain insight into the physiological changes occurring in subjects with cystic fibrosis (CF) after autogenic drainage (AD). Changes in respiratory system resistance (Rrs), reactance (Xrs), and spirometry were analyzed in adult CF subjects after a single AD physiotherapy session. Methods This prospective observational study was conducted during the annual check-up of adult CF subjects in stable condition. Spirometry and Rrs and Xrs measurements using the forced oscillations technique at 5, 11, and 19 hertz (Hz) were performed before and 30 min after a 20-min AD session. Control CF subjects were tested at baseline and 50 min without AD. Results are expressed as mean ± standard deviation or median [interquartile range]. Results Thirty subjects were included in the physiotherapy group (age 29 [25–34] years, forced expiratory volume in 1 s (FEV1) 40.3 [30.1–57.9]% predicted) and 11 in the control group (age 31 [28.5–36.5] years, FEV1 43.6 [31.1–51.9] % predicted). No significant changes in any parameter were observed in the control group. AD modestly but significantly increased the forced vital capacity (FVC) and FEV1 (p<0.001). Inspiratory resistance was also significantly improved by AD: Rrs5 from 5.74±2.39 to 5.24±2.17 cmH2O/L/s, p<0.05; Rrs11 from 4.83±1.98 to 4.32±1.7 cmH2O/L/s, p = 0.003; and Rrs19 from 4.18 [3.46–5.07] to 3.86 [2.76–4.98] cmH2O/L/s, p<0.001. In contrast, AD had no significant effects on frequency dependence of resistance (Rrs5–Rrs19) or expiratory resistance. Inspiratory Xrs5, but not ΔXrs5 (expiratory—inspiratory Xrs), was improved by AD (p<0.05). Moderate correlations were detected between the improvement in FEV1 and FVC and inspiratory resistance (r = 0.53, p = 0.005 and r = 0.44, p = 0.02, respectively). Conclusion A single session of AD improved inspiratory airway resistance, except in the distal airways. The forced oscillations technique provides a new tool for understanding the
Design of a 3-Stage ADR for the Soft X-Ray Spectrometer Instrument on the Astro-H Mission

NASA Technical Reports Server (NTRS)

Shirron, Peter J.; Kimball, Mark O.; Wegel, Donald C.; Canavan, Edgar R.; DiPirro, Michael J.

2011-01-01

The Japanese Astro-H mission will include the Soft X-ray Spectrometer (SXS) instrument, whose 36-pixel detector array of ultra-sensitive x-ray microcalorimeters requires cooling to 50 mK. This will be accomplished using a 3-stage adiabatic demagnetization refrigerator (ADR). The design is dictated by the need to operate with full redundancy with both a superfluid helium dewar at 1.3 K or below, and with a 4.5 K Joule-Thomson (JT) cooler. The ADR is configured as a 2-stage unit that is located in a well in the helium tank, and a third stage that is mounted to the top of the helium tank. The third stage is directly connected through two heat switches to the JT cooler and the helium tank, and manages heat flow between the two. When liquid helium is present, the 2-stage ADR operates in a single-shot manner using the superfluid helium as a heat sink. The third stage may be used independently to reduce the time-average heat load on the liquid to extend its lifetime. When the liquid is depleted, the 2nd and 3rd stages operate as a continuous ADR to maintain the helium tank at as low a temperature as possible - expected to be 1.2 K - and the 1st stage cools from that temperature as a single-stage, single-shot ADR. The ADR s design and operating modes are discussed, along with test results of the prototype 3-stage ADR.
VizieR Online Data Catalog: UY UMa and EF Boo compiled time of minima (Yu+, 2017)

NASA Astrophysics Data System (ADS)

Yu, Y.-X.; Zhang, X.-D.; Hu, K.; Xiang, F.-Y.

2017-11-01

In order to construct the (O-C) diagram to analyze the period change of UY UMa, we have performed a careful search for all available times of light minima. A total of 76 times of light minima were collected and listed in Table 2. >From the literatures and two well-known databases (i.e., the O-C gateway (http://var.astro.cz/ocgate) and the Lichtenknecker database of the BAV (http://www.bav-astro.de/LkDB/index.php)), we have collected a total of 75 available times of light minima for EF Boo, which are summarized in Table 3. (3 data files).
Modelling and Analysis Capabilities for Lightweight Masts

DTIC Science & Technology

2001-02-01

manufactured by Astro Aerospace Corporation in Carpinteria, California for NASA’s Johnson Space Center in Houston. The mast structure was a 750 mm...step iii. Design Parameters • Design variables Moduli: E11, E22, E33, G12, G23, G13, ᝼, ជ, ᝽ Strengths: FXT, FXC , FYT, FYC, FZT, FZC, FXY
E-cigarette puffing patterns associated with high and low nicotine e-liquid strength: effects on toxicant and carcinogen exposure.

PubMed

Cox, Sharon; Kośmider, Leon; McRobbie, Hayden; Goniewicz, Maciej; Kimber, Catherine; Doig, Mira; Dawkins, Lynne

2016-09-20

Contrary to intuition, use of lower strength nicotine e-liquids might not offer reduced health risk if compensatory puffing behaviour occurs. Compensatory puffing (e.g. more frequent, longer puffs) or user behaviour (increasing the wattage) can lead to higher temperatures at which glycerine and propylene glycol (solvents used in e-liquids) undergo decomposition to carbonyl compounds, including the carcinogens formaldehyde and acetaldehyde. This study aims to document puffing patterns and user behaviour associated with using high and low strength nicotine e-liquid and associated toxicant/carcinogen exposure in experienced e-cigarette users (known as vapers herein). A counterbalanced repeated measures design. Non-tobacco smoking vapers; have used an e-cigarette for ≥3 months; currently using nicotine strength e-liquid ≥12mg/mL and a second or third generation device. This study will measure puffing patterns in vapers whilst they use high and low strength nicotine e-liquid under fixed and user-defined settings, each for a week. The 4 counterbalanced conditions are: i) low strength (6mg/mL), fixed settings; ii) low strength user-defined settings; iii) high strength (18mg/mL) fixed settings; iv) high strength user-defined settings. Biomarkers of exposure to toxicants and carcinogens will be measured in urine. In the second phase of this study, toxicant yields will be measured in aerosol generated using a smoking machine operated to replicate the puffing behaviours of each participant. i) Puffing patterns (mean puff number, puff duration, inter-puff interval and mL of liquid consumed) and user behaviour (changes to device settings: voltage and air-flow) associated with using high and low strength nicotine e-liquid. ii) Toxicant/carcinogen exposure associated with the puffing patterns/device settings used by our participants. i) Subjective effects. ii) comparisons with toxicant exposure from tobacco smoke (using documented evidence) and with recommended safety limits
Predictors of High eHealth Literacy in Primary Lung Cancer Survivors.

PubMed

Milne, Robin A; Puts, Martine T E; Papadakos, Janet; Le, Lisa W; Milne, Victoria C; Hope, Andrew J; Catton, Pamela; Giuliani, Meredith E

2015-12-01

Lung cancer survivors are likely to have low health literacy which is an independent risk factor for poorer health outcomes. The eHealth literacy in lung cancer survivors has not been reported. The purposes of this study were to determine self-perceived eHealth literacy levels in lung cancer survivors and to explore predictors of higher eHealth literacy. A cross-sectional study was conducted at the Princess Margaret Cancer Centre in Toronto, Canada. Survivors completed a survey that collected demographic, self-perceived eHealth literacy (using the eHealth Literacy Scale), and quality of life information. Tumor and treatment details were extracted from medical records. Demographic data was summarized using descriptive statistics and compared against those with high and low eHealth literacy using Fisher's exact test. Eighty-three survivors were enrolled over 7 months. Median age was 71 years (range 44-89); 41 survivors (49%) were male. Forty-six (55%) survivors had some college education or higher. Most had access to eResources (78%) via computer, Internet, or smartphone. Fifty-seven (69%) scored 5 or greater (7=excellent) on the overall health scale. Twenty-eight (33.7%) perceived themselves to have high eHealth literacy. There was no statistically significant correlation between eHealth literacy groups and age (p=1.00), gender (p=0.82), living situation (p=1.00), overall health (p=1.00), overall quality of life (QoL) (p=1.00), or histology (p=0.74). High eHealth literacy correlated with the level of education received (p=0.003) and access to eResources (p=0.004). The self-perceived eHealth literacy of lung cancer survivors is generally low.
High fusion performance at high T i/T e in JET-ILW baseline plasmas with high NBI heating power and low gas puffing

NASA Astrophysics Data System (ADS)

Kim, Hyun-Tae; Sips, A. C. C.; Romanelli, M.; Challis, C. D.; Rimini, F.; Garzotti, L.; Lerche, E.; Buchanan, J.; Yuan, X.; Kaye, S.; contributors, JET

2018-03-01

This paper presents the transport analysis of high density baseline discharges in the 2016 experimental campaign of the Joint European Torus with the ITER-Like Wall (JET-ILW), where a significant increase in the deuterium-deuterium (D-D) fusion neutron rate (~2.8 × 1016 s-1) was achieved with stable high neutral beam injection (NBI) powers of up to 28 MW and low gas puffing. Increase in T i exceeding T e were produced for the first time in baseline discharges despite the high electron density; this enabled a significant increase in the thermal fusion reaction rate. As a result, the new achieved record in fusion performance was much higher than the previous record in the same heating power baseline discharges, where T i = T e. In addition to the decreases in collisionality and the increases in ion heating fraction in the discharges with high NBI power, T i > T e can also be attributed to positive feedback between the high T i/T e ratio and stabilisation of the turbulent heat flux resulting from the ion temperature gradient driven mode. The high T i/T e ratio was correlated with high rotation frequency. Among the discharges with identical beam heating power, higher rotation frequencies were observed when particle fuelling was provided by low gas puffing and pellet injection. This reveals that particle fuelling played a key role for achieving high T i/T e, and the improved fusion performance.
High fusion performance at high T i/ T e in JET-ILW baseline plasmas with high NBI heating power and low gas puffing

DOE PAGES

Kim, Hyun-Tae; Sips, A. C. C.; Romanelli, M.; ...

2018-02-01

This article presents the transport analysis of high density baseline discharges in the 2016 experimental campaign of the Joint European Torus with the ITER-Like Wall (JET-ILW), where a significant increase in the deuterium–deuterium (D–D) fusion neutron rate (~2.8 × 10 16 s -1) was achieved with stable high neutral beam injection (NBI) powers of up to 28 MW and low gas puffing. Increase in T i exceeding T e were produced for the first time in baseline discharges despite the high electron density; this enabled a significant increase in the thermal fusion reaction rate. As a result, the new achievedmore » record in fusion performance was much higher than the previous record in the same heating power baseline discharges, where T i = T e. In addition to the decreases in collisionality and the increases in ion heating fraction in the discharges with high NBI power, T i > T e can also be attributed to positive feedback between the high T i/T e ratio and stabilisation of the turbulent heat flux resulting from the ion temperature gradient driven mode. The high T i/T e ratio was correlated with high rotation frequency. Among the discharges with identical beam heating power, higher rotation frequencies were observed when particle fuelling was provided by low gas puffing and pellet injection. Lastly, this reveals that particle fuelling played a key role for achieving high T i/T e, and the improved fusion performance.« less
High fusion performance at high T i/ T e in JET-ILW baseline plasmas with high NBI heating power and low gas puffing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Hyun-Tae; Sips, A. C. C.; Romanelli, M.

This article presents the transport analysis of high density baseline discharges in the 2016 experimental campaign of the Joint European Torus with the ITER-Like Wall (JET-ILW), where a significant increase in the deuterium–deuterium (D–D) fusion neutron rate (~2.8 × 10 16 s -1) was achieved with stable high neutral beam injection (NBI) powers of up to 28 MW and low gas puffing. Increase in T i exceeding T e were produced for the first time in baseline discharges despite the high electron density; this enabled a significant increase in the thermal fusion reaction rate. As a result, the new achievedmore » record in fusion performance was much higher than the previous record in the same heating power baseline discharges, where T i = T e. In addition to the decreases in collisionality and the increases in ion heating fraction in the discharges with high NBI power, T i > T e can also be attributed to positive feedback between the high T i/T e ratio and stabilisation of the turbulent heat flux resulting from the ion temperature gradient driven mode. The high T i/T e ratio was correlated with high rotation frequency. Among the discharges with identical beam heating power, higher rotation frequencies were observed when particle fuelling was provided by low gas puffing and pellet injection. Lastly, this reveals that particle fuelling played a key role for achieving high T i/T e, and the improved fusion performance.« less
Background Measurements Made Above Five Kilometers: A Survey of the Literature

DTIC Science & Technology

1969-06-01

Corporation of America’s Astro - Electronics Division, Greenbelt, Md., 1961. NASA Facts, Vol. II, No. 7, 1965. Nimbus I High Resolution Radiation Data...cept for data in which noise degradation occurred. This applies chiefly to the 2.7- fx data. REFERENCES Unclassified J. Hoyem et al., NOTS - Michigan...et al., "A Revised Analysis of the Solar Spectrum From 2990 to 2635 A," Astro - phys. J., Vol. 119, No. 3, May 1954. UNCLASSIFIED 153
EPE The Extreme Physics Explorer

NASA Technical Reports Server (NTRS)

Garcia, Michael; Elvis, Martin; Bookbinder, Jay; Brenneman, Laura; Bulbul, Esra; Nulsen, Paul; Patnaude, Dan; Smith, Randall; Bandler, Simon; Okajima, Takashi;

2012-01-01

The Extreme Physics Explorer (EPE) is a mission concept that will address fundamental and timely questions in astrophysics which are primary science objectives of IXO. The reach of EPE to the areas outlined in NASA RFI NNH11ZDA018L is shown as a table. The dark green indicates areas in which EPE can do the basic IXO science, and the light green areas where EPE can contribute but will not reach the full IXO capability. To address these science questions, EPE will trace orbits close to the event horizon of black holes, measure black hole spin in active galactic nuclei (AGN), use spectroscopy to characterize outflows and the environment of AGN, map bulk motions and turbulence in galaxy clusters, and observe the process of cosmic feedback where black holes inject energy on galactic and intergalactic scales. EPE gives up the high resolution imaging of IXO in return for lightweight, high TRL foil mirrors which will provide >20 times the effective area of ASTRO-H and similar spatial resolution, with a beam sufficient to study point sources and nearby galaxies and clusters. Advances in micro-calorimeters allow improved performance at high rates with twice the energy resolution of ASTRO-H. A lower TRL option would provide 200 times the area of ASTRO-H using a micro-channel plate optic (MCPO) and a deployable optical bench. Both options are in the middle range of RFI missions at between $600M and $1000M. The EPE foil optic has direct heritage to ASTRO-H, allowing robust cost estimates. The spacecraft is entirely off the shelf and introduces no difficult requirements. The mission could be started and launched in this decade to an L2 orbit, with a three-year lifetime and consumables for 5 years. While ASTRO-H will give us the first taste of high-resolution, non-dispersive X-ray spectroscopy, it will be limited to small numbers of objects in many categories. EPE will give us the first statistically significant samples in each of these categories.

Porous plug phase separator and superfluid film flow suppression system for the soft x-ray spectrometer onboard Hitomi

NASA Astrophysics Data System (ADS)

Ezoe, Yuichiro; DiPirro, Michael; Fujimoto, Ryuichi; Ishikawa, Kumi; Ishisaki, Yoshitaka; Kanao, Kenichi; Kimball, Mark; Mitsuda, Kazuhisa; Mitsuishi, Ikuyuki; Murakami, Masahide; Noda, Hirofumi; Ohashi, Takaya; Okamoto, Atsushi; Satoh, Yohichi; Sato, Kosuke; Shirron, Peter; Tsunematsu, Shoji; Yamaguchi, Hiroya; Yoshida, Seiji

2018-01-01

When using superfluid helium in low-gravity environments, porous plug phase separators are commonly used to vent boil-off gas while confining the bulk liquid to the tank. Invariably, there is a flow of superfluid film from the perimeter of the porous plug down the vent line. For the soft x-ray spectrometer onboard ASTRO-H (Hitomi), its approximately 30-liter helium supply has a lifetime requirement of more than 3 years. A nominal vent rate is estimated as ˜30 μg/s, equivalent to ˜0.7 mW heat load. It is, therefore, critical to suppress any film flow whose evaporation would not provide direct cooling of the remaining liquid helium. That is, the porous plug vent system must be designed to both minimize film flow and to ensure maximum extraction of latent heat from the film. The design goal for Hitomi is to reduce the film flow losses to <2 μg/s, corresponding to a loss of cooling capacity of <40 μW. The design adopts the same general design as implemented for Astro-E and E2, using a vent system composed of a porous plug, combined with an orifice, a heat exchanger, and knife-edge devices. Design, on-ground testing results, and in-orbit performance are described.
Effectiveness of E-Learning for Students Vocational High School Building Engineering Program

NASA Astrophysics Data System (ADS)

Soeparno; Muslim, Supari

2018-04-01

Implementation of vocational learning in accordance with the 2013 curriculum must meet the criteria, one of which is learning to be consistent with advances in technology and information. Technology-based learning in vocational commonly referred to as E-Learning, online (in the network) and WBL (Web-Based Learning). Facts on the ground indicate that based learning technology and information on Vocational High School of Building Engineering is still not going well. The purpose of this research is to know: advantages and disadvantages of learning with E-Learning, conformity of learning with E-Learning with characteristics of students on Vocational High School of Building Engineering and effective learning method based on E-Learning for students on Vocational High School of Building Engineering. Research done by literature method, get the following conclusion as follow: the advantages of E-Learning is learning can be done anywhere and anytime, efficient in accessing materials and tasks, ease of communication and discussion; while the shortage is the need for additional costs for good internet access and lack of social interaction between teachers and students. E-learning is appropriate to basic knowledge competencies, and not appropriate at the level of advanced competencies and skills. Effective E-Learning Based Learning Method on Vocational High School of Building Engineering is a Blended method that is a mix between conventional method and e-learning.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Shayan; Feng, Wenli; Yang, Xiao

Highlights: • We study the impact of leukemic microenvironment on P2X family receptors in Mφs. • Bone marrow and spleen Mφs are studied in Notch1-induced mouse leukemia model. • Increased expression of P2X7R is found in Mφs during the development of leukemia. • Elevated P2X7R-mediated calcium response is found in Mφs at late stage of leukemia. • More apoptotic Mφs are found in bone marrow and spleen at late stage of leukemia. - Abstract: Nucleotides are important players in intercellular signaling communication network. P2X family receptors (P2XRs) are ATP-gated plasma membrane ion channels with diverse biological functions. Macrophages are importantmore » components in the microenvironment of hematopoiesis participating in both physiological and pathological processes. However, the role of P2XRs in macrophages in leukemia has not been established. Here we investigated expression pattern and functions of P2XRs in macrophages from bone marrow (BM) and spleen of Notch1-induced T-ALL mice. Real-time PCR showed that P2XRs except P2X5R were expressed in BM and spleen macrophages. Furthermore, with the development of leukemia, the expression of P2X7R increased in both BM and spleen macrophages whereas expression of P2X1R increased in spleen macrophages. Live cell imaging recoding the Ca{sup 2+} response demonstrated that P2X7R expressed in macrophages was functional. TUNEL and electron microscopy analysis found that apoptotic macrophages were frequently observed in BM and spleen at late stage of leukemia, which was partly contributed by the activation of overexpressed P2X7R. Our results suggested that the intercellular communication mediated by nucleotides might orchestrate in the pathological process of leukemia and could be a potential target for the treatment of leukemia.« less
Low-energy (<20 eV) and high-energy (1000 eV) electron-induced methanol radiolysis of astrochemical interest

NASA Astrophysics Data System (ADS)

Sullivan, Kristal K.; Boamah, Mavis D.; Shulenberger, Katie E.; Chapman, Sitara; Atkinson, Karen E.; Boyer, Michael C.; Arumainayagam, Christopher R.

2016-07-01

We report the first infrared study of the low-energy (<20 eV) electron-induced reactions of condensed methanol. Our goal is to simulate processes which occur when high-energy cosmic rays interact with interstellar and cometary ices, where methanol, a precursor of several prebiotic species, is relatively abundant. The interactions of high-energy radiation, such as cosmic rays (Emax ˜ 1020 eV), with matter produce large numbers of low-energy secondary electrons, which are known to initiate radiolysis reactions in the condensed phase. Using temperature programmed desorption (TPD) and infrared reflection absorption spectroscopy (IRAS), we have investigated low-energy (5-20 eV) and high-energy (˜1000 eV) electron-induced reactions in condensed methanol (CH3OH). IRAS has the benefit that it does not require thermal processing prior to product detection. Using IRAS, we have found evidence for the formation of ethylene glycol (HOCH2CH2OH), formaldehyde (CH2O), dimethyl ether (CH3OCH3), methane (CH4), carbon dioxide (CO2), carbon monoxide (CO), and the hydroxyl methyl radical (·CH2OH) upon both low-energy and high-energy electron irradiation of condensed methanol at ˜85 K. Additionally, TPD results, presented herein, are similar for methanol films irradiated with both 1000 eV and 20 eV electrons. These IRAS and TPD findings are qualitatively consistent with the hypothesis that high-energy condensed phase radiolysis is mediated by low-energy electron-induced reactions. Moreover, methoxymethanol (CH3OCH2OH) could serve as a tracer molecule for electron-induced reactions in the interstellar medium. The results of experiments such as ours may provide a fundamental understanding of how complex organic molecules are synthesized in cosmic ices.
Configurable e-commerce-oriented distributed seckill system with high availability

NASA Astrophysics Data System (ADS)

Zhu, Liye

2018-04-01

The rapid development of e-commerce prompted the birth of seckill activity. Seckill activity greatly stimulated public shopping desire because of its significant attraction to customers. In a seckill activity, a limited number of products will be sold at varying degrees of discount, which brings a huge temptation for customers. The discounted products are usually sold out in seconds, which can be a huge challenge for e-commerce systems. In this case, a seckill system with high concurrency and high availability has very practical significance. This research cooperates with Huijin Department Store to design and implement a seckill system of e-commerce platform. The seckill system supports high concurrency network conditions and is highly available in unexpected situation. In addition, due to the short life cycle of seckill activity, the system has the flexibility to be configured and scalable, which means that it is able to add or re-move system resources on demand. Finally, this paper carried out the function test and the performance test of the whole system. The test results show that the system meets the functional requirements and performance requirements of suppliers, administrators as well as users.
Impaired protection against Trichinella spiralis in mice with high levels of IgE.

PubMed

Watanabe, Naohiro

2014-04-01

Helminth infection induces production of a large amount of immunoglobulin E (IgE) to nonhelminth antigens. Although such "irrelevant" IgE is a major proportion of total IgE in the host, its biological significance remains unclear. Therefore, I examined protective activity against Trichinella spiralis in mice with high levels of IgE by repeated injections of anti-dansyl IgE monoclonal antibody or Nippostrongylus brasiliensis infection. Injected anti-dansyl IgE occupied IgE receptors on mast cells in naive mice. Protective activity against T. spiralis, determined with number of muscle larvae 5weeks after infection, was impaired in mice treated with anti-dansyl IgE. The impaired protection was found in mice treated with anti-dansy IgE 7 and 14days after infection, but not 21 and 28days after infection, indicating that IgE-dependent protection operates at an early stage after infection. In the next experiments, mice were infected with N. brasiliensis 4weeks before T. spiralis infection to obtain high levels of IgE. The protective activity against T. spiralis was decreased by N. brasiliensis infection. On the other hand, protection against T. spiralis was comparable in IgE-deficient SJA/9 mice and in anti-IgE-treated BALB/c mice with or without N. brasiliensis infection, suggesting that impairment of protection is dependent on IgE. These results indicate that the high levels of irrelevant IgE are beneficial for helminths and, alternatively, that anti-helminth IgE antibodies are protective for hosts. In addition, the impaired protection was found in IgE high-responder mice but not in low-responder mice, suggesting that protection against T. spiralis is controlled by IgE responsiveness in the host. Copyright © 2013 Elsevier B.V. All rights reserved.

The Si/CdTe semiconductor Compton camera of the ASTRO-H Soft Gamma-ray Detector (SGD)

NASA Astrophysics Data System (ADS)

Watanabe, Shin; Tajima, Hiroyasu; Fukazawa, Yasushi; Ichinohe, Yuto; Takeda, Shin`ichiro; Enoto, Teruaki; Fukuyama, Taro; Furui, Shunya; Genba, Kei; Hagino, Kouichi; Harayama, Atsushi; Kuroda, Yoshikatsu; Matsuura, Daisuke; Nakamura, Ryo; Nakazawa, Kazuhiro; Noda, Hirofumi; Odaka, Hirokazu; Ohta, Masayuki; Onishi, Mitsunobu; Saito, Shinya; Sato, Goro; Sato, Tamotsu; Takahashi, Tadayuki; Tanaka, Takaaki; Togo, Atsushi; Tomizuka, Shinji

2014-11-01

The Soft Gamma-ray Detector (SGD) is one of the instrument payloads onboard ASTRO-H, and will cover a wide energy band (60-600 keV) at a background level 10 times better than instruments currently in orbit. The SGD achieves low background by combining a Compton camera scheme with a narrow field-of-view active shield. The Compton camera in the SGD is realized as a hybrid semiconductor detector system which consists of silicon and cadmium telluride (CdTe) sensors. The design of the SGD Compton camera has been finalized and the final prototype, which has the same configuration as the flight model, has been fabricated for performance evaluation. The Compton camera has overall dimensions of 12 cm×12 cm×12 cm, consisting of 32 layers of Si pixel sensors and 8 layers of CdTe pixel sensors surrounded by 2 layers of CdTe pixel sensors. The detection efficiency of the Compton camera reaches about 15% and 3% for 100 keV and 511 keV gamma rays, respectively. The pixel pitch of the Si and CdTe sensors is 3.2 mm, and the signals from all 13,312 pixels are processed by 208 ASICs developed for the SGD. Good energy resolution is afforded by semiconductor sensors and low noise ASICs, and the obtained energy resolutions with the prototype Si and CdTe pixel sensors are 1.0-2.0 keV (FWHM) at 60 keV and 1.6-2.5 keV (FWHM) at 122 keV, respectively. This results in good background rejection capability due to better constraints on Compton kinematics. Compton camera energy resolutions achieved with the final prototype are 6.3 keV (FWHM) at 356 keV and 10.5 keV (FWHM) at 662 keV, which satisfy the instrument requirements for the SGD Compton camera (better than 2%). Moreover, a low intrinsic background has been confirmed by the background measurement with the final prototype.
Toward Large FOV High-Resolution X-Ray Imaging Spectrometer: Microwave Multiplexed Readout of 32 TES Microcalorimeters

NASA Technical Reports Server (NTRS)

Yoon, Wonsik; Adams, Joseph S.; Bandler, Simon R.; Chervenak, James A.; Datesman, Aaron M.; Eckart, Megan E.; Finkbeiner, Fred M.; Kelley, Richard L.; Kilbourne, Caroline A.; Miniussi, Antoine R.;

2017-01-01

We performed a small-scale demonstration at GSFC of high-resolution x-ray TES microcalorimeters read out using a microwave SQUID multiplexer. This work is part of our effort to develop detector and readout technologies for future space based x-ray instruments such as the microcalorimeter spectrometer envisaged for Lynx, a large mission concept under development for the Astro 2020 Decadal Survey. In this paper we describe our experiment, including details of a recently designed, microwave-optimized low-temperature setup that is thermally anchored to the 50 mK stage of our laboratory ADR. Using a ROACH2 FPGA at room temperature, we simultaneously read out 32 pixels of a GSFC-built detector array via a NIST-built multiplexer chip with Nb coplanar waveguide resonators coupled to RF SQUIDs. The resonators are spaced 6 MHz apart (at approx. 5.9 GHz) and have quality factors of approximately 15,000. Using flux-ramp modulation frequencies of 160 kHz we have achieved spectral resolutions of 3 eV FWHM on each pixel at 6 keV. We will present the measured system-level noise and maximum slew rates, and briefly describe the implications for future detector and readout design.

Apolipoprotein E expression and behavioral toxicity of high charge, high energy (HZE) particle radiation

NASA Technical Reports Server (NTRS)

Higuchi, Yoshinori; Nelson, Gregory A.; Vazquez, Marcelo; Laskowitz, Daniel T.; Slater, James M.; Pearlstein, Robert D.

2002-01-01

Apolipoprotein E (apoE) is a lipid binding protein that plays an important role in tissue repair following brain injury. In the present studies, we have investigated whether apoE affects the behavioral toxicity of high charge, high energy (HZE) particle radiation. METHODS: Sixteen male apoE knockout (KO) mice and sixteen genetically matched wild-type (WT) C57BL mice were used in this experiment. Half of the KO and half of the WT animals were irradiated with 600 MeV/amu iron particles (2 Gy whole body). The effect of irradiation on motor coordination and stamina (Rotarod test), exploratory behavior (open field test), and spatial working and reference memory (Morris water maze) was assessed. ROTAROD TEST: Performance was adversely affected by radiation exposure in both KO and WT groups at 30 d after irradiation. By 60 d after radiation, the radiation effect was lost in WT, but still apparent in irradiated KO mice. OPEN FIELD TEST: Radiation reduced open field exploratory activity 14, 28, 56, 84, and 168 d after irradiation of KO mice, but had no effect on WT mice. MORRIS WATER MAZE: Radiation adversely affected spatial working memory in the KO mice, but had no discernible effect in the WT mice as assessed 180 d after irradiation. In contrast, irradiated WT mice showed marked impairment of spatial reference memory in comparison to non-irradiated mice, while no effect of radiation was observed in KO mice. CONCLUSIONS: These studies show that apoE expression influences the behavioral toxicity of HZE particle radiation and suggest that apoE plays a role in the repair/recovery from radiation injury of the CNS. ApoE deficiency may exacerbate the previously reported effects of HZE particle radiation in accelerating the brain aging process.
Spacelab

NASA Image and Video Library

1989-01-01

In 1986, NASA introduced a Shuttle-borne ultraviolet observatory called Astro. The Astro Observatory was designed to explore the universe by observing and measuring the ultraviolet radiation from celestial objects. Astronomical targets of observation selected for Astro missions included planets, stars, star clusters, galaxies, clusters of galaxies, quasars, remnants of exploded stars (supernovae), clouds of gas and dust (nebulae), and the interstellar medium. Astro-1 used a Spacelab pallet system with an instrument pointing system and a cruciform structure for bearing the three ultraviolet instruments mounted in a parallel configuration. The three instruments were: The Hopkins Ultraviolet Telescope (HUT), which was designed to obtain far-ultraviolet spectroscopic data from white dwarfs, emission nebulae, active galaxies, and quasars; the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE) which was to study polarized ultraviolet light from magnetic white dwarfs, binary stars, reflection nebulae, and active galaxies; and the Ultraviolet Imaging Telescope (UIT) which was to record photographic images in ultraviolet light of galaxies, star clusters, and nebulae. The star trackers that supported the instrument pointing system were also mounted on the cruciform. Also in the payload bay was the Broad Band X-Ray Telescope (BBXRT), which was designed to obtain high-resolution x-ray spectra from stellar corona, x-ray binary stars, active galactic nuclei, and galaxy clusters. Managed by the Marshall Space Flight Center, the Astro-1 observatory was launched aboard the Space Shuttle Orbiter Columbia (STS-35) on December 2, 1990.
High Technology Service Value Maximization through an MCDM-Based Innovative e-Business Model

NASA Astrophysics Data System (ADS)

Huang, Chi-Yo; Tzeng, Gwo-Hshiung; Ho, Wen-Rong; Chuang, Hsiu-Tyan; Lue, Yeou-Feng

The emergence of the Internet has changed the high technology marketing channels thoroughly in the past decade while E-commerce has already become one of the most efficient channels which high technology firms may skip the intermediaries and reach end customers directly. However, defining appropriate e-business models for commercializing new high technology products or services through Internet are not that easy. To overcome the above mentioned problems, a novel analytic framework based on the concept of high technology customers’ competence set expansion by leveraging high technology service firms’ capabilities and resources as well as novel multiple criteria decision making (MCDM) techniques, will be proposed in order to define an appropriate e-business model. An empirical example study of a silicon intellectual property (SIP) commercialization e-business model based on MCDM techniques will be provided for verifying the effectiveness of this novel analytic framework. The analysis successful assisted a Taiwanese IC design service firm to define an e-business model for maximizing its customer’s SIP transactions. In the future, the novel MCDM framework can be applied successful to novel business model definitions in the high technology industry.
Mapping low- and high-density clouds in astrophysical nebulae by imaging forbidden line emission

NASA Astrophysics Data System (ADS)

Steiner, J. E.; Menezes, R. B.; Ricci, T. V.; Oliveira, A. S.

2009-06-01

Emission line ratios have been essential for determining physical parameters such as gas temperature and density in astrophysical gaseous nebulae. With the advent of panoramic spectroscopic devices, images of regions with emission lines related to these physical parameters can, in principle, also be produced. We show that, with observations from modern instruments, it is possible to transform images taken from density-sensitive forbidden lines into images of emission from high- and low-density clouds by applying a transformation matrix. In order to achieve this, images of the pairs of density-sensitive lines as well as the adjacent continuum have to be observed and combined. We have computed the critical densities for a series of pairs of lines in the infrared, optical, ultraviolet and X-rays bands, and calculated the pair line intensity ratios in the high- and low-density limit using a four- and five-level atom approximation. In order to illustrate the method, we applied it to Gemini Multi-Object Spectrograph (GMOS) Integral Field Unit (GMOS-IFU) data of two galactic nuclei. We conclude that this method provides new information of astrophysical interest, especially for mapping low- and high-density clouds; for this reason, we call it `the ld/hd imaging method'. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the National Science Foundation on behalf of the Gemini partnership: the National Science Foundation (United States); the Science and Technology Facilities Council (United Kingdom); the National Research Council (Canada), CONICYT (Chile); the Australian Research Council (Australia); Ministério da Ciência e Tecnologia (Brazil) and Secretaria de Ciencia y Tecnologia (Argentina). E-mail: steiner@astro.iag.usp.br
WE-H-BRB-01: Overview of the ASTRO-NIH-AAPM 2015 Workshop On Exploring Opportunities for Radiation Oncology in the Era of Big Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benedict, S.

Big Data in Radiation Oncology: (1) Overview of the NIH 2015 Big Data Workshop, (2) Where do we stand in the applications of big data in radiation oncology?, and (3) Learning Health Systems for Radiation Oncology: Needs and Challenges for Future Success The overriding goal of this trio panel of presentations is to improve awareness of the wide ranging opportunities for big data impact on patient quality care and enhancing potential for research and collaboration opportunities with NIH and a host of new big data initiatives. This presentation will also summarize the Big Data workshop that was held at themore » NIH Campus on August 13–14, 2015 and sponsored by AAPM, ASTRO, and NIH. The workshop included discussion of current Big Data cancer registry initiatives, safety and incident reporting systems, and other strategies that will have the greatest impact on radiation oncology research, quality assurance, safety, and outcomes analysis. Learning Objectives: To discuss current and future sources of big data for use in radiation oncology research To optimize our current data collection by adopting new strategies from outside radiation oncology To determine what new knowledge big data can provide for clinical decision support for personalized medicine L. Xing, NIH/NCI Google Inc.« less
Truck Noise VIII : The Determination of the Practical Noise Control Retrofitting of Pre-1970 Truck and Coach Models

DOT National Transportation Integrated Search

1976-06-01

A retrofit noise package was selected for four representative GMC vehicles; i.e., two Heavy Duty Conventionals, one cab-over engine Heavy Duty Astro, and one 53 passenger transit coach, to achieve optimum noise reduction. The selection of this materi...
High-resolution computational ghost imaging and ghost diffraction through turbulence via a beam-shaping method

NASA Astrophysics Data System (ADS)

Luo, Chun-Ling; Zhuo, Ling-Qing

2017-01-01

Imaging through atmospheric turbulence is a topic with a long history and grand challenges still exist in the remote sensing and astro observation fields. In this letter, we try to propose a simple scheme to improve the resolution of imaging through turbulence based on the computational ghost imaging (CGI) and computational ghost diffraction (CGD) setup via the laser beam shaping techniques. A unified theory of CGI and CGD through turbulence with the multi-Gaussian shaped incoherent source is developed, and numerical examples are given to see clearly the effects of the system parameters to CGI and CGD. Our results show that the atmospheric effect to the CGI and CGD system is closely related to the propagation distance between the source and the object. In addition, by properly increasing the beam order of the multi-Gaussian source, we can improve the resolution of CGI and CGD through turbulence relative to the commonly used Gaussian source. Therefore our results may find applications in remote sensing and astro observation.
High Order Well-balanced WENO Scheme for the Gas Dynamics Equations under Gravitational Fields

DTIC Science & Technology

2011-11-12

there exists the hydrostatic balance where the flux produced by the pressure is canceled by the gravitational source term. Many astro - physical...approximation to W (x) to obtain an approximation to W ′(xi) = fx (U(xi, yj)). See again [7, 15] for more details of finite difference WENO schemes in
LAD Prize Talk: Lab Astro and the Origins of the Chemical Elements

NASA Astrophysics Data System (ADS)

Lawler, James E.

2017-06-01

Only a few of the lightest or primordial nuclei were made just after the Big Bang. Other light nuclei up to the Fe-group are made by fusion in stars. Heavier nuclei are made primarily via r(apid)-process and s(low)-process n(eutron)-capture events. Although the s-process n-capture is fairly well understood, the r-process n-capture events remain poorly understood. The relative role of Core Collapse SNe and n-star mergers will likely be understood in the next few decades. I will discuss recent studies of old Metal-Poor stars that are revealing some new details of nucleosynthesis. This progress is due to the availability of high resolution spectra from large ground based telescopes, access to the UV via HST, and better laboratory data. Our laboratory astrophysics program has focused primarily on the measurement of transition probabilities by combining radiative lifetimes with emission branching fractions. The use of Time Resolved Laser Induced Fluorescence (TRLIF) to measure radiative lifetimes in metallic atoms and ions provides an absolute scale for transition probabilities accurate to a few percent [e.g. 1]. The development and application of TRLIF to neutral and ionized atoms of nearly all elements is due to a simple, versatile, and reliable atom/ion beam source based on a hollow cathode discharge [2, 3]. Fourier transform spectrometers (FTSs) are essential in the measurement of emission branching fractions for atoms and ions with dense spectra such as the rare earths [e.g. 4, 5]. A 3 m focal length echelle spectrometer is important to the measurement of weak branches which might otherwise be obscured by multiplex noise in FTS data [6, 7]. References: [1] E. A. Den Hartog et al., ApJS 194: 35 (2011). [2] D. W. Duquette et al., Phys. Rev. A24, 2847 (1981). [3] S. Salih & J. E. Lawler, Phys. Rev. A29, 3753, (1983). [4] J. W. Brault, J. Opt. Soc. Am. 66, 1081 (1976). [5] J. E. Lawler et al., ApJS 182, 51 (2009). [6] M. P. Wood & J. E. Lawler, Appl. Opt. 51, 8407
Electronic Preprints

NASA Astrophysics Data System (ADS)

Hanisch, R.

1999-12-01

Despite the tremendous advances in electronic publications and the increasing rapidity with which papers are now moving from acceptance into ``print,'' preprints continue to be an important mode of communication within the astronomy community. The Los Alamos e-preprint service, astro-ph, provides for rapid and cost-free (to authors and readers) dissemination of manuscripts. As the use of astro-ph has increased the number of paper preprints in circulation to libraries has decreased, and institutional preprint series appear to be waning. It is unfortunate, however, that astro-ph does not function in collaboration with the refereed publications. For example, there is no systematic tracking of manuscripts from preprint to their final, published form, and as a centralized archive it is difficult to distribute the tracking and maintenance functions. It retains documents that have been superseded or have become obsolete. We are currently developing a distributed preprint and document management system which can support both distributed collections of preprints (e.g., traditional institutional preprint series), can link to the LANL collections, can index other documents in the ``grey'' literature (observatory reports, telescope and instrument user's manuals, calls for proposals, etc.), and can function as a manuscript submission tool for the refereed journals. This system is being developed to work cooperatively with the refereed literature so that, for example, links to preprints are updated to links to the final published papers.
High-Fidelity e-Learning: SEI’s Virtual Training Environment (VTE)

DTIC Science & Technology

2009-01-01

Assessment 2.4 Collaboration 2.4.1 Peer-Student Collaboration 2.4.2 Instructor Support 2.5 Accessibility 2.6 Modularity 2.6.1 Design for Re-Use 2.6.2 Design ...ing Environment as an implementation of a high-fidelity e-Ieaming system. This report does not cover concepts of pedagogy or instructional design in e...pedagogical agents. This is the basis for Clark and Mayer’s Personalization principle for designing media for e-learning [Clark & Mayer 2003]. E-learning
Voss at ADVASC Growth Chamber in Destiny module

NASA Image and Video Library

2001-05-22

ISS002-E-6300 (22 May 2001) --- James S. Voss, Expedition Two flight engineer, works with the Advanced Astro Culture (ADVASC) Condensate Fluid Syringe at the ADVASC Growth Chamber in the U.S. Laboratory. The image was taken with a digital still camera.
Placing Tighter Constraints on Mercurian Surface Fe Abundances Through the Synthesis and Characterization of Fe-Poor Silicates

NASA Astrophysics Data System (ADS)

Vander Kaaden, K. E.; McCubbin, F. M.; Rowland, R. L.; Morris, R. V.; Reppart, J. J.; Klima, R. L.

2018-05-01

We have crystallized and characterized synthetic Fe-poor minerals to make advancements towards reconciling the discrepancy between the lack of a 1-µm absorption band observed on the surface of Mercury, despite wt% levels of Fe observed by XRS.
STS-Astro: Astronomy in the focus of Science, Technology and Society and Case Study in Education Distance

NASA Astrophysics Data System (ADS)

Ferreira, O. R.

2014-02-01

The dissertation addresses the focus of Astronomy in Science, Technology and Society [STS}, which the author calls the STS-Astro. Observes the International Year of the Astronomy 2009 [IYA 2009] as one of the greatest experiences STS worldwide, causing unprecedented integration between science, technology and humanities, with positive impacts in many sectors of society and are still worthy of study, specially in Brazil due to the implementation of the International Year of Astronomy, Brazil 2009 [IYABrazil-2009}. Astronomy is also investigated in the area of Education, based mainly on theoretical aspects of educational socio-interacionist of Lev Semenovich Vygotsky (Vygotsky, 1991, 2008 and 2012, p. 103-117) and socio-historical cultural of Paulo Reglus Neves Freire (1979, 1982 and 1996), but when necessary and still keeping the field of constructivism, properly taking advantage of the interactionism and transdisciplinarity of Jean William Fritz Piaget (1983). Concerning Distance Education [DE], it is noted significant growth at the graduate and postgraduate courses. New challenges arise, with the establishment of an increasingly accustomed to Information and Communication Technologies [ICT] and the teaching methodologies to be used and developed, with Astronomy becoming an important instrument in the teaching-learning process associated technologies. Using the methodology of action research, we proceeded with a case study involving 26 students of the discipline of Astronomy Topics applied to Education, between November 1 and December 17, 2012, of the postgraduation courses in Distance Education at the Universidade Cruzeiro do Sul [Southern Cross University]. The results obtained permit statistical surveys therefore quantitative, but also qualitative information about the teaching-learning Astronomy by DE. Analyses of performance and progress of each student and set permit a finding interaction among those involved in the mediation of the teacher-tutor who, in turn
Finite temperature effects on the X-ray absorption spectra of energy related materials

NASA Astrophysics Data System (ADS)

Pascal, Tod; Prendergast, David

2014-03-01

We elucidate the role of room-temperature-induced instantaneous structural distortions in the Li K-edge X-ray absorption spectra (XAS) of crystalline LiF, Li2SO4, Li2O, Li3N and Li2CO3 using high resolution X-ray Raman spectroscopy (XRS) measurements and first-principles density functional theory calculations within the eXcited electron and Core Hole (XCH) approach. Based on thermodynamic sampling via ab-initio molecular dynamics (MD) simulations, we find calculated XAS in much better agreement with experiment than those computed using the rigid crystal structure alone. We show that local instantaneous distortion of the atomic lattice perturbs the symmetry of the Li 1 s core-excited-state electronic structure, broadening spectral line-shapes and, in some cases, producing additional spectral features. This work was conducted within the Batteries for Advanced Transportation Technologies (BATT) Program, supported by the U.S. Department of Energy Vehicle Technologies Program under Contract No. DE-AC02-05CH11231.
USSR Report, Space

DTIC Science & Technology

1984-11-14

objects which have received no particular attention from astro sä»: äI r *r= xs srsr äTS?- Leo." FTD/SNAP CSO: 1866/25 43 YAKUTSK INSTITUTE’S...adapted for extended (up to 5 hours daily) observation of x-ray and ultra- violet sources. The heart of the station is the solar- astro astro ...in space is provided by two sensors: a solar one which "looks at" the sun and an astro one aimed at a bright navigational star. The scan zone of
Developing Customer Oriented eHealth Services to High Schools in City of Espoo.

PubMed

Rosenqvist, Susanne; Rajalahti, Elina

2016-01-01

The purpose of this research was to study the hopes and needs of high school first grade students and student healthcare nurses about development of eServices for student healthcare mainly by improving existing ITC solutions and planning new eHealth services. The secondary purpose was to innovate how to share general knowledge about health to students. Four (n=4) high school nurses were group interviewed and an electronic questionnaire was made for high school first grade students. Nearly 15% (n=247) of the target group answered the questionnaire. Preventive eHealth solutions need improvements in student health care in Finland.
Spacelab

NASA Image and Video Library

1990-03-20

This photograph was taken during the integration of the Astro-1 mission payloads at the Kennedy Space Center on March 20, 1990, showing the Broad Band X-Ray Telescope (BBXRT) at the left, as three telescopes for the Astro-1 Observatory are settled into the Orbiter Columbia payload bay. Above Earth's atmospheric interference, Astro-1 would make precise measurements of objects such as planets, stars, and galaxies in relatively small fields of view and would observe and measure ultraviolet radiation from celestial objects. The Astro-1 used a Spacelab pallet system with an instrument pointing system and a cruciform structure for bearing the three ultraviolet instruments mounted in a parallel configuration. The three instruments were: The Hopkins Ultraviolet Telescope (HUT), which was designed to obtain far-ultraviolet spectroscopic data from white dwarfs, emission nebulae, active galaxies, and quasars; the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE) which was to study polarized ultraviolet light from magnetic white dwarfs, binary stars, reflection nebulae, and active galaxies; and the Ultraviolet Imaging Telescope (UIT), which was to record photographic images in ultraviolet light of galaxies, star clusters, and nebulae. The star trackers that supported the instrument pointing system, were also mounted on the cruciform. Also in the payload bay was the Broad Band X-Ray Telescope (BBXRT), which was designed to obtain high-resolution x-ray spectra from stellar corona, x-ray binary stars, active galactic nuclei, and galaxy clusters. Managed by the Marshall Space Flight Center, the Astro-1 observatory was launched aboard the Space Shuttle Orbiter Columbia (STS-35) on December 2, 1990.

High-Risk Human Papillomaviral Oncogenes E6 and E7 Target Key Cellular Pathways to Achieve Oncogenesis.

PubMed

Yeo-Teh, Nicole S L; Ito, Yoshiaki; Jha, Sudhakar

2018-06-08

Infection with high-risk human papillomavirus (HPV) has been linked to several human cancers, the most prominent of which is cervical cancer. The integration of the viral genome into the host genome is one of the manners in which the viral oncogenes E6 and E7 achieve persistent expression. The most well-studied cellular targets of the viral oncogenes E6 and E7 are p53 and pRb, respectively. However, recent research has demonstrated the ability of these two viral factors to target many more cellular factors, including proteins which regulate epigenetic marks and splicing changes in the cell. These have the ability to exert a global change, which eventually culminates to uncontrolled proliferation and carcinogenesis.
An introduction to food and waterborne viruses: diseases, transmission, outbreaks, detection and control

USDA-ARS?s Scientific Manuscript database

Enteric viruses are the number one cause of foodborne illness throughout the world. In addition to foods, contaminated drinking water is another major cause of enteric viral illness. Among the enteric viruses are the noroviruses, hepatitis A and E viruses, enteric adenoviruses, rotavirus, and astro...
The Empirical Canadian High Arctic Ionospheric Model (E-CHAIM): Bottomside Parameterization

NASA Astrophysics Data System (ADS)

Themens, D. R.; Jayachandran, P. T.

2017-12-01

It is well known that the International Reference Ionosphere (IRI) suffers reduced accuracy in its representation of monthly median ionospheric electron density at high latitudes. These inaccuracies are believed to stem, at least in part, from a historical lack of data from these regions. Now, roughly thirty and forty years after the development of the original URSI and CCIR foF2 maps, respectively, there exists a much larger dataset of high latitude observations of ionospheric electron density. These new measurements come in the form of new ionosonde deployments, such as those of the Canadian High Arctic Ionospheric Network, the CHAMP, GRACE, and COSMIC radio occultation missions, and the construction of the Poker Flat, Resolute, and EISCAT Incoherent Scatter Radar systems. These new datasets afford an opportunity to revise the IRI's representation of the high latitude ionosphere. Using a spherical cap harmonic expansion to represent horizontal and diurnal variability and a Fourier expansion in day of year to represent seasonal variations, we have developed a new model of the bottomside ionosphere's electron density for the high latitude ionosphere, above 50N geomagnetic latitude. For the peak heights of the E and F1 layers (hmE and hmF1, respectively), current standards use a constant value for hmE and either use a single-parameter model for hmF1 (IRI) or scale hmF1 with the F peak (NeQuick). For E-CHAIM, we have diverged from this convention to account for the greater variability seen in these characteristics at high latitudes, opting to use a full spherical harmonic model description for each of these characteristics. For the description of the bottomside vertical electron density profile, we present a single-layer model with altitude-varying scale height. The scale height function is taken as the sum three scale height layer functions anchored to the F2 peak, hmF1, and hmE. This parameterization successfully reproduces the structure of the various bottomside
High dietary zinc feeding promotes persistence of multi-resistant E. coli in the swine gut.

PubMed

Ciesinski, Lisa; Guenther, Sebastian; Pieper, Robert; Kalisch, Martin; Bednorz, Carmen; Wieler, Lothar H

2018-01-01

High levels of zinc oxide are used frequently as feed additive in pigs to improve gut health and growth performance and are still suggested as an alternative to antimicrobial growth promoters. However, we have recently described an increase of multi-resistant E. coli in association to zinc feeding in piglets. This previous study focused on clonal diversity of E. coli, observing the effect on multi-resistant strains by chance. To shed further light into this highly important topic and falsify our previous findings, we performed a zinc pig feeding trial where we specifically focused on in-depth analysis of antimicrobial resistant E. coli. Under controlled experimental conditions, piglets were randomly allocated to a high dietary zinc (zinc group) and a background zinc feeding group (control group). At different ages samples were taken from feces, digesta, and mucosa and absolute E. coli numbers were determined. A total of 2665 E. coli isolates were than phenotypically tested for antimicrobial resistance and results were confirmed by minimum inhibitory concentration testing for random samples. In piglets fed with high dietary zinc, we detected a substantial increase of multi-resistant E. coli in all gut habitats tested, ranging from 28.9-30.2% multi-resistant E. coli compared to 5.8-14.0% in the control group. This increase was independent of the total number of E. coli. Interestingly, the total amount of the E. coli population decreased over time. Thus, the increase of the multi-resistant E. coli populations seems to be linked with persistence of the resistant population, caused by the influence of high dietary zinc feeding. In conclusion, these findings corroborate our previous report linking high dietary zinc feeding of piglets with the occurrence of antimicrobial resistant E. coli and therefore question the feeding of high dietary zinc oxide as alternative to antimicrobial growth promoters.
High dietary zinc feeding promotes persistence of multi-resistant E. coli in the swine gut

PubMed Central

Guenther, Sebastian; Pieper, Robert; Kalisch, Martin; Bednorz, Carmen; Wieler, Lothar H.

2018-01-01

High levels of zinc oxide are used frequently as feed additive in pigs to improve gut health and growth performance and are still suggested as an alternative to antimicrobial growth promoters. However, we have recently described an increase of multi-resistant E. coli in association to zinc feeding in piglets. This previous study focused on clonal diversity of E. coli, observing the effect on multi-resistant strains by chance. To shed further light into this highly important topic and falsify our previous findings, we performed a zinc pig feeding trial where we specifically focused on in-depth analysis of antimicrobial resistant E. coli. Under controlled experimental conditions, piglets were randomly allocated to a high dietary zinc (zinc group) and a background zinc feeding group (control group). At different ages samples were taken from feces, digesta, and mucosa and absolute E. coli numbers were determined. A total of 2665 E. coli isolates were than phenotypically tested for antimicrobial resistance and results were confirmed by minimum inhibitory concentration testing for random samples. In piglets fed with high dietary zinc, we detected a substantial increase of multi-resistant E. coli in all gut habitats tested, ranging from 28.9–30.2% multi-resistant E. coli compared to 5.8–14.0% in the control group. This increase was independent of the total number of E. coli. Interestingly, the total amount of the E. coli population decreased over time. Thus, the increase of the multi-resistant E. coli populations seems to be linked with persistence of the resistant population, caused by the influence of high dietary zinc feeding. In conclusion, these findings corroborate our previous report linking high dietary zinc feeding of piglets with the occurrence of antimicrobial resistant E. coli and therefore question the feeding of high dietary zinc oxide as alternative to antimicrobial growth promoters. PMID:29373597
Statistics of the MASIV 5 GHZ VLA Scintillation Survey

DTIC Science & Technology

2007-10-01

76, Epping, NSW, Australia, E-mail: david.jauncey@csiro.au James Lovell : School of Mathematics & Physics, University of Tasmania, GPO Box 252...Technology, Pasadena CA 91125, E-mail: jpm@astro.caltech.edu Hayley Bignall: Joint Institute for VLBI in Europe, Postbus 2, 7900 AA Dwingeloo, The...369, 449 [7] Lovell , J. E. J., et al., First Results from MASIV: The Microarcsecond Scintillation- induced Variability Survey, 2003, AJ, 126, 1699
E-cigarette Use and Beliefs Among Urban Public High School Students in North Carolina.

PubMed

Anand, Vivek; McGinty, Kaye L; O'Brien, Kevin; Guenthner, Gregory; Hahn, Ellen; Martin, Catherine A

2015-07-01

The aim of this study was to examine the prevalence, attitudes, and risk factors associated with electronic cigarette (e-cigarette) use among high school students in tobacco growing state. A 47-item e-cigarette questionnaire modeled after Monitoring the Future with additional information about demographics, adolescent and family nicotine use, and school and health care interventions was designed, piloted, and administered to public high school students (N = 3,298) in May 2013, in an urban county in North Carolina. Completers (2,769/3,298) were aged 16.4 years (standard deviation ± 1.4) with 48.9% males and 43.9% African-American, 38% white, and 4.6% Hispanics. The majority (77.3%) knew about e-cigarettes; 15.2% reported that they had tried an e-cigarette, and 60% reported that e-cigarettes were safe or had minimal health hazards. Only 5.4% reported that schools had offered information about e-cigarette use. One quarter (24.9%) reported ever cigarette smoking, and 13.3% reported ever using smokeless tobacco. E-cigarette use was positively associated with older age, tobacco use, male gender, Caucasian race, mother's e-cigarette use, biological parents' tobacco use, and lower academic performance, whereas negatively associated with having a mother who never used e-cigarettes, not knowing any e-cigarette users, and living with mother (p < .05). E-cigarette use and awareness is evident among high school students in North Carolina. A high number of smokers and smokeless tobacco users are using e-cigarettes simultaneously, and many perceive e-cigarettes as healthy and with minimal health hazards. Also, there is limited school-based education about e-cigarettes. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Engaging Scientists in Meaningful E/PO: How the NASA SMD E/PO Community Addresses the Needs of the Higher Ed Community

NASA Astrophysics Data System (ADS)

Manning, James; Meinke, Bonnie K.; Schultz, Gregory R.; Smith, Denise A.; Lawton, Brandon L.; Gurton, Suzanne; NASA Astrophysics E/PO Community

2015-01-01

The NASA Astrophysics Science Education and Public Outreach Forum (SEPOF) coordinates the work of NASA Science Mission Directorate (SMD) Astrophysics EPO projects and their teams to bring cutting-edge discoveries of NASA missions to the introductory astronomy college classroom. The Astrophysics Forum assists scientist and educator involvement in SMD E/PO (uniquely poised to foster collaboration between scientists with content expertise and educators with pedagogy expertise) and makes SMD E/PO resources and expertise accessible to the science and education communities. We present three new opportunities for college instructors to bring the latest NASA discoveries in Astrophysics into their classrooms.To address the expressed needs of the higher education community, the Astrophysics Forum collaborated with the Astrophysics E/PO community, researchers, and Astronomy 101 instructors to place individual science discoveries and learning resources into context for higher education audiences. Among these resources are two Resource Guides on the topics of cosmology and exoplanets, each including a variety of accessible sources.The Astrophysics Forum also coordinates the development of the Astro 101 slide set series--5 to 7-slide presentations on new discoveries from NASA Astrophysics missions relevant to topics in introductory astronomy courses. These sets enable Astronomy 101 instructors to include new discoveries not yet in their textbooks into the broader context of the course: http://www.astrosociety.org/education/astronomy-resource-guides/.The Astrophysics Forum also coordinated the development of 12 monthly Universe Discovery Guides, each featuring a theme and a representative object well-placed for viewing, with an accompanying interpretive story, strategies for conveying the topics, and supporting NASA-approved education activities and background information from a spectrum of NASA missions and programs: http://nightsky.jpl.nasa.gov/news-display.cfm?News_ID=611
Search for high-mass e+e- resonances in pp collisions at sqrt[s]=1.96 TeV.

PubMed

Aaltonen, T; Adelman, J; Akimoto, T; Albrow, M G; Alvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Apresyan, A; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzurri, P; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Beecher, D; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Beringer, J; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bridgeman, A; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burke, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Calancha, C; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Chwalek, T; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Cordelli, M; Cortiana, G; Cox, C A; Cox, D J; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; Dagenhart, D; Datta, M; Davies, T; de Barbaro, P; De Cecco, S; Deisher, A; De Lorenzo, G; Dell'Orso, M; Deluca, C; Demortier, L; Deng, J; Deninno, M; Derwent, P F; di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Elagin, A; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Frank, M J; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garberson, F; Garcia, J E; Garfinkel, A F; Genser, K; Gerberich, H; Gerdes, D; Gessler, A; Giagu, S; Giakoumopoulou, V; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C M; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Han, B-Y; Han, J Y; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hays, C; Heck, M; Heijboer, A; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hewamanage, S; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jayatilaka, B; Jeon, E J; Jha, M K; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Kar, D; Karchin, P E; Kato, Y; Kephart, R; Keung, J; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, H W; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kreps, M; Kroll, J; Krop, D; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhr, T; Kulkarni, N P; Kurata, M; Kusakabe, Y; Kwang, S; Laasanen, A T; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, E; Lee, H S; Lee, S W; Leone, S; Lewis, J D; Lin, C-S; Linacre, J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, C; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lovas, L; Lucchesi, D; Luci, C; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Macqueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, C; Marino, C P; Martin, A; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Mathis, M; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzione, A; Merkel, P; Mesropian, C; Miao, T; Miladinovic, N; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyake, H; Moggi, N; Moon, C S; Moore, R; Morello, M J; Morlok, J; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Nett, J; Neu, C; Neubauer, M S; Neubauer, S; Nielsen, J; Nodulman, L; Norman, M; Norniella, O; Nurse, E; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Griso, S Pagan; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Peiffer, T; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Pianori, E; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Pueschel, E; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Rekovic, V; Renton, P; Renz, M; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rodriguez, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Safonov, A; Sakumoto, W K; Saltó, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savoy-Navarro, A; Schlabach, P; Schmidt, A; Schmidt, E E; Schmidt, M A; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sforza, F; Sfyrla, A; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shiraishi, S; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spreitzer, T; Squillacioti, P; Stanitzki, M; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Strycker, G L; Stuart, D; Suh, J S; Sukhanov, A; Suslov, I; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thom, J; Thompson, A S; Thompson, G A; Thomson, E; Tipton, P; Ttito-Guzmán, P; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Tourneur, S; Trovato, M; Tsai, S-Y; Tu, Y; Turini, N; Ukegawa, F; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Vellidis, C; Veszpremi, V; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Volobouev, I; Volpi, G; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wagner-Kuhr, J; Wakisaka, T; Wallny, R; Wang, C; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Weinelt, J; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Wilbur, S; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Würthwein, F; Wynne, S M; Xie, S; Yagil, A; Yamamoto, K; Yamaoka, J; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zhang, X; Zheng, Y; Zucchelli, S

2009-01-23

A search for high-mass resonances in the e+e- final state is presented based on 2.5 fb(-1) of sqrt[s]=1.96 TeV pp collision data from the CDF II detector at the Fermilab Tevatron. The largest excess over the standard model prediction is at an e+e- invariant mass of 240 GeV/c2. The probability of observing such an excess arising from fluctuations in the standard model anywhere in the mass range of 150-1000 GeV/c2 is 0.6% (equivalent to 2.5sigma). We exclude the standard model coupling Z' and the Randall-Sundrum graviton for k/MPl=0.1 with masses below 963 and 848 GeV/c2 at the 95% credibility level, respectively.
Astrobites: The Astro-ph Reader's Digest For Undergraduates

NASA Astrophysics Data System (ADS)

Sanders, Nathan; Newton, E. R.; Czekala, I.; Rosenfeld, K.; Dressing, C. D.; Gifford, D.; Suresh, J.; Schneider, E.; Morley, C.; Kohler, S.

2011-05-01

Do you know an undergraduate embarking on a career in research in astronomy or a related field? Point them to Astrobites, a daily astrophysical literature blog for undergraduates written by graduate students (http://astroph.wordpress.com). Our goal is to present one interesting paper per day in a brief format that is accessible to undergraduate students in the physical sciences who are interested in active research. We not only try to summarize new work, but also to provide valuable context for readers not yet familiar with the astrophysical literature. For example, our posts discuss the long term goals motivating the field, astronomical jargon, and how the technical methods work. Special posts offer career guidance for undergraduates (e.g. how to select a graduate school) and detail personal experiences (e.g. observing at a Chilean telescope or attending a AAS meeting). We present sample Astrobites posts, readership statistics, and the results of our periodic reader surveys from our first semester of blogging (Spring 2011).
Post-Mission Smoothing and Analysis of the Measurements of the Change in the Deflection of the Vertical Obtained by the Rapid Geodetic Survey System (RGSS) at the White Sands Test Range

DTIC Science & Technology

1976-09-01

sail 0 W 0 . 3 I ii..W’Lai W LhdL. )U) UJ 10 I D uC ) (M La 60A0 0 6 010 1 S- Y DC C. IiJ(J 0 0 z0 P.-w uiL~j I JLLJ U. 419 " fx I 1 1- C r LL) 0 Z 0...8217•:I ’ I . ......-..... #29-VALLEY ASTRO . , 0. . . . .. . . . . . .. L . . . * I . 1 I . I - i -:) -.. .....-. . ... ..2.-.A.EY . -R...34- ... .. . !I i IS " " t’%l : E ,, El, #2•J - VALLEY ASTRO 0J - ---- . . . ..:. o - o" #31 - SALT 0.00 0.20 0.40 0’.60 0.60 1.00 1.20 TIIME IN HOUhS HI ,.1
E-cigarette Use Among High School and Middle School Adolescents in Connecticut

PubMed Central

Morean, Meghan E.; Camenga, Deepa R.; Cavallo, Dana A.; Kong, Grace

2015-01-01

Introduction: There is limited evidence on electronic cigarette (e-cigarette) use among U.S. adolescents. Methods: Cross-sectional, anonymous surveys conducted in 4 high schools (HS; n = 3,614) and 2 middle schools (MS; n = 1,166) in Connecticut in November 2013 examined e-cigarette awareness, use patterns, susceptibility to future use, preferences, product components used (battery type, nicotine content, flavors), and sources of marketing and access. Results: High rates of awareness (MS: 84.3%; HS: 92.0%) and of lifetime (3.5% MS, 25.2 % HS) and current (1.5% MS, 12% HS) use of e-cigarettes was observed. Among those who had not tried e-cigarettes, 26.4% of MS and 31.7% of HS students reported being susceptible to future use. Males (OR = 1.70, p < .01), older students (OR = 1.39, p < .05), Caucasians (OR = 2.01, p < .001), ever cigarette smokers (OR = 13.04, p < .001), and current cigarette smokers (OR = 65.11, p < .001) were more likely to be lifetime e-cigarette users and to report greater future susceptibility (males: OR = 1.30; Caucasians: OR = 1.14; ever cigarette smokers; OR = 3.85; current cigarette smokers; OR = 9.81; ps < .01–.001). Among MS students who were lifetime e-cigarette users, 51.2% reported that e-cigarette was the first tobacco product they had tried. E-cigarettes that were rechargeable and had sweet flavors were most popular. Smokers preferred e-cigarettes to cigarettes. Current cigarette smokers were more likely to initiate with nicotine-containing e-cigarettes, and ever and never cigarette smokers to initiate with e-cigarettes without nicotine. Primary sources for e-cigarette advertisements were televisions and gas stations and, for acquiring e-cigarettes, were peers. Conclusions: Longitudinal monitoring of e-cigarette use among adolescents and establishment of policies to limit access are imperatively needed. PMID:25385873
Calibration of the Microcalorimeter Spectrometer On-Board the Hitomi (Astro-H) Observatory (invited)

NASA Technical Reports Server (NTRS)

Eckart, M. E.; Boyce, K. R.; Brown, G. V.; Chiao, M. P.; Fujimoto, R.; Haas, D.; Den Herder, J.-W.; Ishisaki, Y.; Kelley, R. L.; Kilbourne, C. A.;

2016-01-01

The Hitomi Soft X-ray Spectrometer (SXS) was a pioneering non-dispersive imaging x-ray spectrometer with 5 eV FWHM energy resolution, consisting of an array of 36 silicon-thermistor microcalorimeters at the focus of a high-throughput soft x-ray telescope. The instrument enabled astrophysical plasma diagnostics in the 0.3-12 keV band. We introduce the SXS calibration strategy and corresponding ground calibration measurements that took place from 2012-2015, including both the characterization of the microcalorimeter array and measurements of the x-ray transmission of optical blocking filters.

High-resolution Ceres Low Altitude Mapping Orbit Atlas derived from Dawn Framing Camera images

NASA Astrophysics Data System (ADS)

Roatsch, Th.; Kersten, E.; Matz, K.-D.; Preusker, F.; Scholten, F.; Jaumann, R.; Raymond, C. A.; Russell, C. T.

2017-06-01

The Dawn spacecraft Framing Camera (FC) acquired over 31,300 clear filter images of Ceres with a resolution of about 35 m/pxl during the eleven cycles in the Low Altitude Mapping Orbit (LAMO) phase between December 16 2015 and August 8 2016. We ortho-rectified the images from the first four cycles and produced a global, high-resolution, uncontrolled photomosaic of Ceres. This global mosaic is the basis for a high-resolution Ceres atlas that consists of 62 tiles mapped at a scale of 1:250,000. The nomenclature used in this atlas was proposed by the Dawn team and was approved by the International Astronomical Union (IAU). The full atlas is available to the public through the Dawn Geographical Information System (GIS) web page [http://dawngis.dlr.de/atlas] and will become available through the NASA Planetary Data System (PDS) (http://pdssbn.astro.umd.edu/).
Adlai E. Stevenson High School, Bilingual Academic and Technical Education for Youth Program. O.E.E. Evaluation Report, 1982-1983.

ERIC Educational Resources Information Center

Keyes, Jose Luis; Collins, Carla

The Bilingual Academic and Technical Education for Youth (BATEY) Program completed its third and final year of funding at Adlai E. Stevenson High School, Bronx, New York. In 1982-83, the program offered bilingual instruction and support services to approximately 300 Hispanic students of limited English proficiency in grades 9-12. Although the…
New Observations of Soft X-ray (0.5-5 keV) Solar Spectra

NASA Astrophysics Data System (ADS)

Caspi, A.; Woods, T. N.; Mason, J. P.; Jones, A. R.; Warren, H. P.

2013-12-01

The solar corona is the brightest source of X-rays in the solar system, and the X-ray emission is highly variable on many time scales. However, the actual solar soft X-ray (SXR) (0.5-5 keV) spectrum is not well known, particularly during solar quiet periods, as, with few exceptions, this energy range has not been systematically studied in many years. Previous observations include high-resolution but very narrow-band spectra from crystal spectrometers (e.g., Yohkoh/BCS), or integrated broadband irradiances from photometers (e.g., GOES/XRS, TIMED/XPS, etc.) that lack detailed spectral information. In recent years, broadband measurements with moderate energy resolution (~0.5-0.7 keV FWHM) were made by SphinX on CORONAS-Photon and SAX on MESSENGER, although they did not extend to energies below ~1 keV. We present observations of solar SXR emission obtained using new instrumentation flown on recent SDO/EVE calibration rocket underflights. The photon-counting spectrometer, a commercial Amptek X123 with a silicon drift detector and an 8 μm Be window, measures the solar disk-integrated SXR emission from ~0.5 to >10 keV with ~0.15 keV FWHM resolution and 1 s cadence. A novel imager, a pinhole X-ray camera using a cooled frame-transfer CCD (15 μm pixel pitch), Ti/Al/C filter, and 5000 line/mm Au transmission grating, images the full Sun in multiple spectral orders from ~0.1 to ~5 nm with ~10 arcsec/pixel and ~0.01 nm/pixel spatial and spectral detector scales, respectively, and 10 s cadence. These instruments are prototypes for future CubeSat missions currently being developed. We present new results of solar observations on 04 October 2013 (NASA sounding rocket 36.290). We compare with previous results from 23 June 2012 (NASA sounding rocket 36.286), during which solar activity was low and no signal was observed above ~4 keV. We compare our spectral and imaging measurements with spectra and broadband irradiances from other instruments, including SDO/EVE, GOES/XRS, TIMED
Toward Large Field-of-View High-Resolution X-ray Imaging Spectrometers: Microwave Multiplexed Readout of 28 TES Microcalorimeters

NASA Astrophysics Data System (ADS)

Yoon, W.; Adams, J. S.; Bandler, S. R.; Becker, D.; Bennett, D. A.; Chervenak, J. A.; Datesman, A. M.; Eckart, M. E.; Finkbeiner, F. M.; Fowler, J. W.; Gard, J. D.; Hilton, G. C.; Kelley, R. L.; Kilbourne, C. A.; Mates, J. A. B.; Miniussi, A. R.; Moseley, S. H.; Noroozian, O.; Porter, F. S.; Reintsema, C. D.; Sadleir, J. E.; Sakai, K.; Smith, S. J.; Stevenson, T. R.; Swetz, D. S.; Ullom, J. N.; Vale, L. R.; Wakeham, N. A.; Wassell, E. J.; Wollack, E. J.

2018-04-01

We performed small-scale demonstrations at GSFC of high-resolution X-ray TES microcalorimeters read out using a microwave SQUID multiplexer. This work is part of our effort to develop detector and readout technologies for future space-based X-ray instruments such as the microcalorimeter spectrometer envisaged for Lynx, a large mission concept under development for the Astro 2020 Decadal Survey. In this paper we describe our experiment, including details of a recently designed, microwave-optimized low-temperature setup that is thermally anchored to the 55 mK stage of our laboratory ADR. Using a ROACH2 FPGA at room temperature, we read out pixels of a GSFC-built detector array via a NIST-built multiplexer chip with Nb coplanar waveguide resonators coupled to rf-SQUIDs. The resonators are spaced 6 MHz apart (at ˜ 5.9 GHz) and have quality factors of ˜ 15,000. In our initial demonstration, we used flux-ramp modulation frequencies of 125 kHz to read out 5 pixels simultaneously and achieved spectral resolutions of 2.8-3.1 eV FWHM at 5.9 keV. Our subsequent work is ongoing: to-date we have achieved a median spectral resolution of 3.4 eV FWHM at 5.9 keV while reading out 28 pixels simultaneously with flux-ramp frequencies of 160 kHz. We present the measured system-level noise and maximum slew rates and briefly describe our future development work.
The Liberating Role of Astronomy in an Old Farmer's Almanac: David Rittenhouse's "Useful Knowledge" and a Benjamin Banneker Almanac for 1792

NASA Astrophysics Data System (ADS)

Walker, Theodore, Jr.

2012-06-01

Traditionally, astronomy met theology and political ethics in almanacs. As presented in early New England almanacs of the farmer's type, astronomy was deity-affirming and liberty-oriented. The old English label for astronomy that affirms theology was "Astro-theology" (William Derham, 1715). The New England rendering of astro-theology was so strongly oriented towards liberty that it can now be labeled astro-liberation theology. This 21st century label is appropriate because 18th century New England printers and astronomers used astronomy to demonstrate the glory of the Creator (astro-theology) and to encourage liberation from colonialism and slavery (astro-liberation theology). A philosophy of astronomy as "useful knowledge' expressed by David Rittenhouse in 1775 - and implicit in a Benjamin Banneker almanac for 1792 - included liberty-oriented visions of planet Earth as seen from outer space, and liberty-oriented visions of intelligent life on other planets orbiting other stars.
IMAGE: A Design Integration Framework Applied to the High Speed Civil Transport

NASA Technical Reports Server (NTRS)

Hale, Mark A.; Craig, James I.

1993-01-01

Effective design of the High Speed Civil Transport requires the systematic application of design resources throughout a product's life-cycle. Information obtained from the use of these resources is used for the decision-making processes of Concurrent Engineering. Integrated computing environments facilitate the acquisition, organization, and use of required information. State-of-the-art computing technologies provide the basis for the Intelligent Multi-disciplinary Aircraft Generation Environment (IMAGE) described in this paper. IMAGE builds upon existing agent technologies by adding a new component called a model. With the addition of a model, the agent can provide accountable resource utilization in the presence of increasing design fidelity. The development of a zeroth-order agent is used to illustrate agent fundamentals. Using a CATIA(TM)-based agent from previous work, a High Speed Civil Transport visualization system linking CATIA, FLOPS, and ASTROS will be shown. These examples illustrate the important role of the agent technologies used to implement IMAGE, and together they demonstrate that IMAGE can provide an integrated computing environment for the design of the High Speed Civil Transport.
Intrinsic Geodesy

DTIC Science & Technology

1952-03-01

to which astro - nomical latitudes and longitudes are referred. Moreover, the direction in space of the axis has a physical reality and maV be used for...product, or mixed product, or box product of three vectors i, U, E is the scalar V -i Bi~ F- iXiU.E - ’Exg . B - FXc i a- =1. .X F- F.x = .cx5 (EI-1) Z

Astro-Dynasty

NASA Astrophysics Data System (ADS)

Belkora, Leila

2001-05-01

Four generations of Struves directed eight observatories over two centuries. The first, Wilhelm Struve moved to Estonia from northern Germany to escape Napoleon's military conscription. He pursued university studies and ended up running an observatory for 20 years. Raising his family at the observatory in isolated conditions encouraged his offspring to follow his career path. The last, Otto Struve, was the first director of McDonald Observatory. The Struves were winners of several Gold Medals from Britain's Royal Astronomical Society for their research.
Sporadic E movement followed with a pencil beam high frequency radar

NASA Astrophysics Data System (ADS)

From, W. R.

1983-12-01

Several types of sporadic E are observed using the 5.80 and 3.84-MHz Bribie Island pencil-beam high-frequency radar. Blanketing Es takes the form of large flat sheets with ripples in them. Non-blanketing Es is observed to be small clouds that drift across the field of view (40 deg). There is continuous gradation of sporadic E structure between these extremes. There are at least four different physical means by which sporadic E clouds may apparently move. It is concluded that non-blanketing sporadic E consists of separate clouds which follow the movement of the constructive interference between internal gravity waves rather than being blown by the background wind.
High resolution spectroscopy over 8500-8750 Å for GAIA <= 7500 K. II. A library of synthetic spectra for T_eff <= 7500 K

NASA Astrophysics Data System (ADS)

Munari, U.; Castelli, F.

2000-01-01

We present a library of synthetic spectra characterized by -2.5 <= [Z/Z_sun] <= +0.5, 4.5 <= log g<= 1.0, and Teff <= 7500 K computed at the same lambda /bigtriangleup lambda = 20000 resolving power of the observed spectra given in Paper I for 131 standard stars mapping the MKK spectral classification system. This range of parameters includes the majority of the galactic stars expected to dominate the GAIA target population, i.e. F-G-K-M type stars with metallicity ranging from that of the galactic globular clusters to Population I objects. Extension to Teff > 7500 K will be given later on in this series. The 254 synthetic spectra presented here are based on Kurucz's codes and line data and have been computed over a more extended wavelength interval (7650-8750 Ä) than that currently baselined for implementation on GAIA, i.e. the 8500-8750 Ä. This last range is dominated by the near-IR Ca II triplet and the head of the Paschen series. The more extended wavelength range allows us to investigate the behaviour of other strong near-IR spectral features (severely contaminated by telluric absorptions in ground-based observed spectra) as the K I doublet (7664, 7699 Ä), the Na I doublet (8183, 8194 Ä) and the lines of Fe I multiplet N.60 at 8327 and 8388 Ä. The synthetic spectra support our previous conclusions about the superior performance of the Paschen/Ca II 8500-8750 Ä region in meeting the GAIA requirements when compared to other near-IR intervals of similar bigtriangleup lambda = 250 Ä. Table 2 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html Figures 5-93 are only available in electronic form at the http://www.edpsciences.org The spectra are also available in electronic form at the CDS or via the personal HomePage http://ulisse.pd.astro.it/Astro/Atlases/
High current polarized electron source for future eRHIC

NASA Astrophysics Data System (ADS)

Wang, Erdong

2018-05-01

The high current and high bunch charge polarized electron source is essential for cost reduction of Linac-Ring (L-R) eRHIC. In the baseline design, electron beam from multiple guns (probably 4-8) will be combined using deflection plates or accumulate ring. Each gun aims to deliver electron beam with 10 mA average current and 5.3 nC bunch charge. With total 50 mA and 5.3 nC electron beam, this beam combining design could use for generating positron too. The gun has been designed, fabricated and expected to start commissioning by the mid of this year. In this paper, we will present the DC gun design parameters and beam combine schemes. Also, we will describe the details of gun design and the strategies to demonstrate high current high charge polarized electron beam from this source.
A dual-mode highly efficient class-E stimulator controlled by a low-Q class-E power amplifier through duty cycle.

PubMed

Chiu, Hung-Wei; Lu, Chien-Chi; Chuang, Jia-min; Lin, Wei-Tso; Lin, Chii-Wann; Kao, Ming-Chien; Lin, Mu-Lien

2013-06-01

This paper presents the design flow of two high-efficiency class-E amplifiers for the implantable electrical stimulation system. The implantable stimulator is a high-Q class-E driver that delivers a sine-wave pulsed radiofrequency (PRF) stimulation, which was verified to have a superior efficacy in pain relief to a square wave. The proposed duty-cycle-controlled class-E PRF driver designed with a high-Q factor has two operational modes that are able to achieve 100% DC-AC conversion, and involves only one switched series inductor and an unchanged parallel capacitor. The measured output amplitude under low-voltage (LV) mode using a 22% duty cycle was 0.98 V with 91% efficiency, and under high-voltage (HV) mode using a 47% duty cycle was 2.95 V with 92% efficiency. These modes were inductively controlled by a duty-cycle detector, which can detect the duty-cycle modulated signal generated from the external complementary low-Q class-E power amplifier (PA). The design methodology of the low-Q inductive interface for a non-50% duty cycle is presented. The experimental results exhibits that the 1.5-V PA that consumes DC power of 14.21 mW was able to deliver a 2.9-V sine wave to a 500 Ω load. The optimal 60% drain efficiency of the system from the PA to the load was obtained at a 10-mm coupling distance.
ASTROS Enhancements. Volume I- ASTRO User’s Manual

DTIC Science & Technology

1993-03-01

alternative functions. The mechanisms by which these more advanced features are invoked are included in this manual but no attempt is made to provide... advanced topics are treated in the Programmer’s and Application Manuals which document the individual modules in the system and their interactions...of the more advanced features of the system without cluttering the discussion with details of the input structures. The detailed documentation of the
ASTROS Enhancements. Volume 2. ASTRO Programmer’s Manual

DTIC Science & Technology

1993-03-01

MMGETB ( ’ BMAT ’, ’RSP’, N*M, ’MAXT’, IB, ISTAT ) CALL MMGETB ( ’CMAT’, ’RSP’, N*M, ’MAXT’, IC, ISTAT ) DO 100 I = 1, N*M II =I - 1 Z ( IC + II ) = Z
High-Dimensional Heteroscedastic Regression with an Application to eQTL Data Analysis

PubMed Central

Daye, Z. John; Chen, Jinbo; Li, Hongzhe

2011-01-01

Summary We consider the problem of high-dimensional regression under non-constant error variances. Despite being a common phenomenon in biological applications, heteroscedasticity has, so far, been largely ignored in high-dimensional analysis of genomic data sets. We propose a new methodology that allows non-constant error variances for high-dimensional estimation and model selection. Our method incorporates heteroscedasticity by simultaneously modeling both the mean and variance components via a novel doubly regularized approach. Extensive Monte Carlo simulations indicate that our proposed procedure can result in better estimation and variable selection than existing methods when heteroscedasticity arises from the presence of predictors explaining error variances and outliers. Further, we demonstrate the presence of heteroscedasticity in and apply our method to an expression quantitative trait loci (eQTLs) study of 112 yeast segregants. The new procedure can automatically account for heteroscedasticity in identifying the eQTLs that are associated with gene expression variations and lead to smaller prediction errors. These results demonstrate the importance of considering heteroscedasticity in eQTL data analysis. PMID:22547833
E-Reading Comprehension versus Conventional Reading Comprehension of Junior High Students

ERIC Educational Resources Information Center

Stevens, Brian

2014-01-01

Technology is an increasing part in the lives of junior high students, but little is known about how this technology affects their reading. Reading comprehension from e-books is compared to reading comprehension from conventional print books with junior high students. The problem is that students may be reading from a medium that is less than the…
Adlai E. Stevenson High School Bilingual Academic and Technical Education for Youth Program (BATEY). O.E.E. Evaluation Report, 1981-1982.

ERIC Educational Resources Information Center

Bulkin, Elly; And Others

The Bilingual Academic and Technical Education for Youth Program (BATEY) provides English as a second language (ESL) and bilingual instruction with a vocational focus to foreign born (98 percent of them Hispanic) students at Adlai E. Stevenson High School, Bronx, New York. Under the program, Title VII funds support administrative and support…
High-Throughput Screening of HECT E3 Ubiquitin Ligases Using UbFluor.

PubMed

Foote, Peter K; Krist, David T; Statsyuk, Alexander V

2017-09-14

HECT E3 ubiquitin ligases are responsible for many human disease phenotypes and are promising drug targets; however, screening assays for HECT E3 inhibitors are inherently complex, requiring upstream E1 and E2 enzymes as well as ubiquitin, ATP, and detection reagents. Intermediate ubiquitin thioesters and a complex mixture of polyubiquitin products provide further opportunities for off-target inhibition and increase the complexity of the assay. UbFluor is a novel ubiquitin thioester that bypasses the E1 and E2 enzymes and undergoes direct transthiolation with HECT E3 ligases. The release of fluorophore upon transthiolation allows fluorescence polarization detection of HECT E3 activity. In the presence of inhibitors, HECT E3 activity is ablated, and thus no reaction and no change in FP are observed. This assay has been adapted for high-throughput screening of small molecules against HECT E3 ligases, and its utility has been proven in the discovery of HECT E3 ligase inhibitors. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.
Oxide vapor distribution from a high-frequency sweep e-beam system

NASA Astrophysics Data System (ADS)

Chow, R.; Tassano, P. L.; Tsujimoto, N.

1995-03-01

Oxide vapor distributions have been determined as a function of operating parameters of a high frequency sweep e-beam source combined with a programmable sweep controller. We will show which parameters are significant, the parameters that yield the broadest oxide deposition distribution, and the procedure used to arrive at these conclusions. A design-of-experimental strategy was used with five operating parameters: evaporation rate, sweep speed, sweep pattern (pre-programmed), phase speed (azimuthal rotation of the pattern), profile (dwell time as a function of radial position). A design was chosen that would show which of the parameters and parameter pairs have a statistically significant effect on the vapor distribution. Witness flats were placed symmetrically across a 25 inches diameter platen. The stationary platen was centered 24 inches above the e-gun crucible. An oxide material was evaporated under 27 different conditions. Thickness measurements were made with a stylus profilometer. The information will enable users of the high frequency e-gun systems to optimally locate the source in a vacuum system and understand which parameters have a major effect on the vapor distribution.
A study of low mass x-ray binaries

NASA Technical Reports Server (NTRS)

Catura, Richard C.

1994-01-01

The entire effort under this contract during the period through January 1992 was devoted to a study of the cost and schedule required to put an upgraded Aries payload on the ASTRO-SPAS carrier provided by the German space agency, DARA. The ASTRO-SPAS is flown on the Space Shuttle, deployed by the crew for 5 to 7 days of free-flying observations and then recovered and returned to Earth. The spectrograph was to be provided by a collaboration involving the Lockheed Palo Alto Research Laboratory (LPARL), the Center for Astrophysics and Space Astronomy (CASA) at the U. of Colorado and the Mullard Space Science Laboratory (MSSL) in England. The payload for the ASTRO-SPAS mission included our own spectrograph and an instrument provided by Dr. Joachim Trumper of the Max Planck Institute (MPI) in Garching, Germany. A meeting was held in late July, 1991 with German scientists, DARA representatives and MBB, the ASTRO-SPAS spacecraft contractor. Sufficient information was exchanged to allow us to complete the study and the name LEXSA (Low Energy X-ray Spectrograph on ASTRO-SPAS) was given to our instrument and HERTA (High Energy x-Ray Telescope on ASTR0-SPAS) to the German instrument. The combination was called SPECTRO-SPAS. On October 1, 1991 CASA and LPARL submitted a cost and brief technical proposal to NASA on results of the study. The total cost over 4 fiscal years was 6.16 M dollars including CASA costs. NASA Headquarters was briefed on 3 October on details of the proposal. They found our costs reasonable, but indicated that the NASA FY '92 budget is extremely tight, they could not readily identify where the -S2.3M for LEXSA could be found and it was not clear that FY '93 would improve.
A standard definition of disease freedom is needed for prostate cancer: undetectable prostate specific antigen compared with the American Society of Therapeutic Radiology and Oncology consensus definition.

PubMed

Critz, Frank A

2002-03-01

Freedom from prostate cancer is defined by undetectable prostate specific antigen (PSA) after surgery and the American Society of Therapeutic Radiology and Oncology (ASTRO) criteria are recommended for irradiation. Whether these definitions of disease freedom are comparable was evaluated in this study. From August 1992 to August 1996 simultaneous irradiation with prostate 125iodine implantation followed by external beam irradiation was performed in 591 consecutive men with stage T1T2NX prostate cancer. All patients had a transperineal implant and none received neoadjuvant hormones. Disease freedom was defined by a PSA cutoff of 0.2 ng./ml. and the ASTRO consensus definition. Median followup was 6 years (range 5 to 8). Of the 591 men in this study 65 had recurrence by ASTRO criteria and 93 had recurrence by a PSA cutoff of 0.2 ng./ml., which was a significant difference (p = 0.001). On multivariate analysis of the factors related to disease-free status the definition of disease freedom, pretreatment PSA and Gleason score were highly significant. Of the 528 men with a minimum 5-year PSA followup the 8-year disease-free survival rate by ASTRO criteria was 99% in those who achieved a PSA nadir of 0.2 ng./ml. and 16% in those with a nadir of 0.3 to 1 ng./ml. Of the 469 disease-free patients by ASTRO criteria with a minimum 5-year followup 455 (97%) achieved a PSA nadir of 0.2 ng./ml. or less. The definition of freedom from prostate cancer significantly affects treatment results. A standard definition is needed and a PSA cutoff of 0.2 ng./ml. is suggested as the standard for all curative treatments for localized prostate cancer.
STS-67 crew insignia

NASA Image and Video Library

1994-10-01

STS067-S-001 (October 1994) --- Observation and remote exploration of the Universe in the ultraviolet wavelengths of light are the focus of the STS-67/ASTRO-2 mission, as depicted in the crew patch designed by the crew members. The insignia shows the ASTRO-2 telescopes in the space shuttle Endeavour's payload bay, orbiting high above Earth's atmosphere. The three sets of rays, diverging from the telescope on the patch atop the Instrument Pointing System (IPS), correspond to the three ASTRO-2 telescopes -- the Hopkins Ultraviolet Telescope (HUT), the Ultraviolet Imaging Telescope (UIT), and the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE). The telescopes are co-aligned to simultaneously view the same astronomical object, as shown by the convergence of rays on the NASA symbol. This symbol also represents the excellence of the union of the NASA teams and universality's in the exploration of the universe through astronomy. The celestial targets of ASTRO-2 include the observation of planets, stars and galaxies shown in the design. The two small atoms represent the search in the ultraviolet spectrum for the signature of primordial helium in intergalactic space left over from the Big Bang. The observations performed on ASTRO-2 will contribute to man's knowledge and understanding of the vast universe, from the planets in out system to the farthest reaches of space. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA
High Frequency Backscatter from the Polar and Auroral E-Region Ionosphere

NASA Astrophysics Data System (ADS)

Forsythe, Victoriya V.

The Earth's ionosphere contains collisional and partially-ionized plasma. The electric field, produced by the interaction between the Earth's magnetosphere and the solar wind, drives the plasma bulk motion, also known as convection, in the F-region of the ionosphere. It can also destabilize the plasma in the E-region, producing irregularities or waves. Intermediate-scale waves with wavelengths of hundreds of meters can cause scintillation and fading of the Global Navigation Satellite System (GNSS) signals, whereas the small-scale waves (lambda < 100 m) can scatter radar signals, making possible detection of these plasma structures and measurements of their characteristics such as their phase velocity and intensity. In this work, production of the decameter-scale (lambda ≈ 10 m) irregularities in the ionospheric E-region (100-120 km in altitude) at high latitudes is investigated both theoretically, using linear fluid theory of plasma instability processes that generate small-scale plasma waves, and experimentally, by analyzing data collected with the newly-deployed high-southern-latitude radars within the Super Dual Auroral Radar Network (SuperDARN). The theoretical part of this work focuses on symmetry properties of the general dispersion relation that describes wave propagation in the collisional plasma in the two-stream and gradient-drift instability regimes. The instability growth rate and phase velocity are examined under the presence of a background parallel electric field, whose influence is demonstrated to break the spatial symmetry of the wave propagation patterns. In the observational part of this thesis, a novel dual radar setup is used to examine E-region irregularities in the magnetic polar cap by probing the E-region along the same line from opposite directions. The phase velocity analysis together with raytracing simulations demonstrated that, in the polar cap, the radar backscatter is primarily controlled by the plasma density conditions. In
Peer-review Platform for Astronomy Education Activities

NASA Astrophysics Data System (ADS)

Heenatigala, Thilina; Russo, Pedro; Gomez, Edward; Strubbe, Linda

2015-08-01

Astronomy educators and teachers worldwide commonly request and search for high-quality astronomy activities to do with their students. Hundreds of astronomy education activities exist, as well as many resource repositories to find them. However, the quality of such resources is highly variable as they are not updated regularly or limited with content review. Since its launch in 2013, astroEDU has been addressing these issues and more by following a peer-review process. Each activity submitted is reviewed by an educator and a professional astronomer, balancing both the scientific and educational value of the content. Moreover, the majority of the reviewers are invited from IAU commissions related to the field of the activity, as an effort to get IAU members actively involved in the project. The website code, activities and layout design are open-access in order to make them accessible and adoptable for educators around the world. Furthermore the platform harnesses the OAD volunteer database to develop existing astronomy education activities into the astroEDU activity format. Published activities are also pushed to partner repositories and each activity is registered for DOI, allowing authors to cite their work. To further test the activities and improve the platform, astroEDU editorial team organises workshops.
The Relationship Between N(Htotal) and E(B-V) at High Galactic Latitude

NASA Astrophysics Data System (ADS)

Doppel, Jessica Erin; Magnani, Loris A.

2017-06-01

We studied the gas-to-dust ratio at high Galactic latitudes (|b| ≥ 20° and 30°). The gas content was measured by the column density of atomic hydrogen from the Leiden/Argentine/Bonn survey and the dust by E(B-V) from the Schlafly et al. (2014) compilation. We do not see significant variation as a function of galactic quadrant or hemisphere. Our results are similar to other studies that used different techniques for deriving N(HI), N(H2), or E(B-V). Like Liszt (2013), we see a higher slope [N(HI)/E(B-V)] if we choose only those points with E(B-V) ≤ 0.1 mag. We also see the break in slope he noted at 0.08 mag. We examined lines of sight that coincided with the Georgia/Harvard Smithsonian CfA high-latitude CO(1-0) surveys. Although at |b| ≥ 30° there were only about 200 CO detections, those points lie systematically below our best fit lines to the data. We can convert the CO line intensities to N(H2) and determine a global CO-H2 conversion factor for the high latitude sky.
The HEASARC in 2016: 25 Years and Counting

NASA Astrophysics Data System (ADS)

Drake, Stephen Alan; Smale, Alan P.

2016-04-01

The High Energy Astrophysics Archival Research Center or HEASARC (http://heasarc.gsfc.nasa.gov/) has been the NASA astrophysics discipline archive supporting multi-mission cosmic X-ray and gamma-ray astronomy research for 25 years, and, through its LAMBDA (Legacy Archive for Microwave Background Data Analysis: http://lambda.gsfc.nasa.gov/) component, the archive for cosmic microwave background data for the last 8 years. The HEASARC is the designated archive which supports NASA's Physics of the Cosmos theme (http://pcos.gsfc.nasa.gov/).The HEASARC provides a unified archive and software structure aimed both at 'legacy' high-energy missions such as Einstein, EXOSAT, ROSAT, RXTE, and Suzaku, contemporary missions such as Fermi, Swift, XMM-Newton, Chandra, NuSTAR, etc., and upcoming missions, such as Astro-H and NICER. The HEASARC's high-energy astronomy archive has grown so that it presently contains more than 80 terabytes (TB) of data from 30 past and present orbital missions. The user community downloaded 160 TB of high-energy data from the HEASARC last year, i.e., an amount equivalent to twice the size of the archive.We discuss some of the upcoming new initiatives and developments for the HEASARC, including the arrival of public data from the JAXA/NASA Astro-H mission, expected to have been launched in February 2016, and the NASA mission of opportunity Neutron Star Interior Composition Explorer (NICER), expected to be deployed in late summer 2016. We also highlight some of the new software and web initiatives of the HEASARC, and discuss our plans for the next 3 years.
Autonomous star tracker based on active pixel sensors (APS)

NASA Astrophysics Data System (ADS)

Schmidt, U.

2017-11-01

Star trackers are opto-electronic sensors used onboard of satellites for the autonomous inertial attitude determination. During the last years, star trackers became more and more important in the field of the attitude and orbit control system (AOCS) sensors. High performance star trackers are based up today on charge coupled device (CCD) optical camera heads. The Jena-Optronik GmbH is active in the field of opto-electronic sensors like star trackers since the early 80-ties. Today, with the product family ASTRO5, ASTRO10 and ASTRO15, all marked segments like earth observation, scientific applications and geo-telecom are supplied to European and Overseas customers. A new generation of star trackers can be designed based on the APS detector technical features. The measurement performance of the current CCD based star trackers can be maintained, the star tracker functionality, reliability and robustness can be increased while the unit costs are saved.

High-Density IgE Recognition of the Major Grass Pollen Allergen Phl p 1 Revealed with Single-Chain IgE Antibody Fragments Obtained by Combinatorial Cloning

PubMed Central

Madritsch, Christoph; Gadermaier, Elisabeth; Roder, Uwe W.; Lupinek, Christian; Valenta, Rudolf; Flicker, Sabine

2015-01-01

The timothy grass pollen allergen Phl p 1 belongs to the group 1 of highly cross-reactive grass pollen allergens with a molecular mass of ~25–30 kDa. Group 1 allergens are recognized by >95% of grass pollen allergic patients. We investigated the IgE recognition of Phl p 1 using allergen-specific IgE-derived single-chain variable Ab fragments (IgE-ScFvs) isolated from a combinatorial library constructed from PBMCs of a grass pollen–allergic patient. IgE-ScFvs reacted with recombinant Phl p 1 and natural group 1 grass pollen allergens. Using synthetic Phl p 1–derived peptides, the binding sites of two ScFvs were mapped to the N terminus of the allergen. In surface plasmon resonance experiments they showed comparable high-affinity binding to Phl p 1 as a complete human IgE-derived Ab recognizing the allergens’ C terminus. In a set of surface plasmon resonance experiments simultaneous allergen recognition of all three binders was demonstrated. Even in the presence of the three binders, allergic patients’ polyclonal IgE reacted with Phl p 1, indicating high-density IgE recognition of the Phl p 1 allergen. Our results show that multiple IgE Abs can bind with high density to Phl p 1, which may explain the high allergenic activity and sensitizing capacity of this allergen. PMID:25637023
The edge transient-current technique (E-TCT) with high energy hadron beam

NASA Astrophysics Data System (ADS)

Gorišek, Andrej; Cindro, Vladimir; Kramberger, Gregor; Mandić, Igor; Mikuž, Marko; Muškinja, Miha; Zavrtanik, Marko

2016-09-01

We propose a novel way to investigate the properties of silicon and CVD diamond detectors for High Energy Physics experiments complementary to the already well-established E-TCT technique using laser beam. In the proposed setup the beam of high energy hadrons (MIPs) is used instead of laser beam. MIPs incident on the detector in the direction parallel to the readout electrode plane and perpendicular to the edge of the detector. Such experiment could prove very useful to study CVD diamond detectors that are almost inaccessible for the E-TCT measurements with laser due to large band-gap as well as to verify and complement the E-TCT measurements of silicon. The method proposed is being tested at CERN in a beam of 120 GeV hadrons using a reference telescope with track resolution at the DUT of few μm. The preliminary results of the measurements are presented.
Highlighting High Performance: Michael E. Capuano Early Childhood Center; Somerville, Massachusetts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2006-03-01

This brochure describes the key high-performance building features of the Michael E. Capuano Early Childhood Center. The brochure was paid for by the Massachusetts Technology Collaborative as part of their Green Schools Initiative. High-performance features described are daylighting and energy-efficient lighting, indoor air quality, solar and wind energy, building envelope, heating and cooling systems, water conservation, and acoustics. Energy cost savings are also discussed.
Diagnostic performance of HPV E6/E7 mRNA assay for detection of cervical high-grade intraepithelial neoplasia and cancer among women with ASCUS Papanicolaou smears.

PubMed

Ren, Chenchen; Zhu, Yuanhang; Yang, Li; Zhang, Xiaoan; Liu, Ling; Ren, Chunying

2018-02-01

The aim of this study was to investigate the clinical performance of high risk (HR) HPV E6/E7 mRNA assay in detecting cervical high-grade intraepithelial neoplasia and cancer among women with atypical squamous cells of undetermined significance (ASCUS) Papanicolaou (Pap) smears. A total of 160 patients with ASCUS who underwent HR-HPV DNA assay, HR-HPV E6/E7 mRNA assay and colposcopy biopsy at Third Affiliated Hospital of Zhengzhou University, China, from December 2015 to March 2017, were enrolled. Logistic regression analysis was used to evaluate the relationship between pathological results with clinical biologic factors. Univariate analysis showed that the qualitative results of HR-HPV DNA, qualitative results of HR-HPV E6/E7 mRNA and expression levels of HR-HPV E6/E7 mRNA were risk factors of high-grade cervical intraepithelial neoplasia (CIN) and cervical cancer (all P < 0.05). Multivariable analysis found that only the expression levels of HR-HPV E6/E7 mRNA was associated with high-grade CIN and cervical cancer (OR = 8.971, 95% CI = 2.572-31.289, P = 0.001). An optimal cut-off value of ≥ 558.26 copies/ml was determined using receiver operating characteristic curve, and specificity of cut-off value were higher than E6/E7 mRNA qualitative assay and DNA qualitative assay. HPV E6/E7 mRNA quantitative assay may be a valuable tool in triage of ASCUS pap smears. A high specificity of E6/E7 mRNA quantitative assay as a triage test in women with ASCUS can be translated into a low referral for colposcopy.
Empty substrate integrated waveguide technology for E plane high-frequency and high-performance circuits

NASA Astrophysics Data System (ADS)

Belenguer, Angel; Cano, Juan Luis; Esteban, Héctor; Artal, Eduardo; Boria, Vicente E.

2017-01-01

Substrate integrated circuits (SIC) have attracted much attention in the last years because of their great potential of low cost, easy manufacturing, integration in a circuit board, and higher-quality factor than planar circuits. A first suite of SIC where the waves propagate through dielectric have been first developed, based on the well-known substrate integrated waveguide (SIW) and related technological implementations. One step further has been made with a new suite of empty substrate integrated waveguides, where the waves propagate through air, thus reducing the associated losses. This is the case of the empty substrate integrated waveguide (ESIW) or the air-filled substrate integrated waveguide (air-filled SIW). However, all these SIC are H plane structures, so classical H plane solutions in rectangular waveguides have already been mapped to most of these new SIC. In this paper a novel E plane empty substrate integrated waveguide (ESIW-E) is presented. This structure allows to easily map classical E plane solutions in rectangular waveguide to this new substrate integrated solution. It is similar to the ESIW, although more layers are needed to build the structure. A wideband transition (covering the frequency range between 33 GHz and 50 GHz) from microstrip to ESIW-E is designed and manufactured. Measurements are successfully compared with simulation, proving the validity of this new SIC. A broadband high-frequency phase shifter (for operation from 35 GHz to 47 GHz) is successfully implemented in ESIW-E, thus proving the good performance of this new SIC in a practical application.
Spacelab

NASA Image and Video Library

1990-12-09

This is a presentation of two comparison images of the Spiral Galaxy M81 in the constellation URA Major. The galaxy is about 12-million light years from Earth. The left image is the Spiral Galaxy M81 as photographed by the Ultraviolet Imaging Telescope (UIT) during the Astro-1 Mission (STS-35) on December 9, 1990. This UIT photograph, made with ultraviolet light, reveals regions where new stars are forming at a rapid rate. The right image is a photograph of the same galaxy in red light made with a 36-inch (0.9-meter) telescope at the Kitt Peak National Observatory near Tucson, Arizona. The Astro Observatory was designed to explore the universe by observing and measuring ultraviolet radiation from celestial objects. Three instruments made up the Astro Observatory: The Hopkins Ultraviolet Telescope (HUT), the Ultraviolet Imaging Telescope (UIT), and the Wisconsin Ultraviolet Photo-Polarimetry Experiment (WUPPE). The Marshall Space Flight Center had management responsibilities for the Astro-1 mission. The Astro-1 Observatory was launched aboard the Space Shuttle Orbiter Columbia (STS-35) on December 2, 1990.
Prostate-specific antigen (PSA) bounce and other fluctuations: which biochemical relapse definition is least prone to PSA false calls? An analysis of 2030 men treated for prostate cancer with external beam or brachytherapy with or without adjuvant androgen deprivation therapy.

PubMed

Pickles, Tom

2006-04-01

To determine the false call (FC) rate for prostate-specific antigen (PSA) relapse according to nine different PSA relapse definitions after a PSA fluctuation (bounce) has occurred after external beam radiation therapy (EBRT) or brachytherapy, with or without adjuvant androgen deprivation therapy. An analysis of a prospective database of 2030 patients was conducted. Prostate-specific antigen relapse was scored according to the American Society for Therapeutic Radiology and Oncology (ASTRO), Vancouver, threshold + n, and nadir + n definitions for the complete data set and then compared against a truncated data set, with data subsequent to the height of the bounce deleted. The FC rate was calculated for each definition. The bounce rate, with this very liberal definition of bounce, was 58% with EBRT and 84% with brachytherapy. The FC rate was lowest with nadir + 2 and + 3 definitions (2.2% and 1.6%, respectively) and greatest with low-threshold and ASTRO definitions (32% and 18%, respectively). The ASTRO definition was particularly susceptible to FC when androgen deprivation therapy was used with radiation (24%). New definitions of biochemical non-evidence of disease that are more robust than the ASTRO definition have been identified. Those with the least FC rates are the nadir + 2 and nadir + 3 definitions, both of which are being considered to replace the ASTRO definition by the 2005 meeting of the Radiation Therapy Oncology Group-ASTRO consensus panel.
Evaluation of the Houston biochemical relapse definition in men treated with prolonged neoadjuvant and adjuvant androgen ablation and assessment of follow-up lead-time bias.

PubMed

Pickles, Tom; Kim-Sing, Charmaine; Morris, W James; Tyldesley, Scott; Paltiel, Chuck

2003-09-01

To validate the Houston prostate-specific antigen relapse definition in a mature cohort of men treated with external beam radiotherapy (EBRT) and adjuvant androgen ablation (AA) and men treated with EBRT monotherapy, and to compare these results with the American Society for Therapeutic Radiology and Oncology (ASTRO) and Vancouver prostate-specific antigen relapse (biochemical no evidence of disease) definitions. A prospective database of 1490 men treated with EBRT, with or without AA, was examined. The impact on hazard proportions, as well as the predictive ability, of the Houston, ASTRO, and Vancouver definitions was tested. For all patients, the Houston definition was more accurate (79.5%) than the ASTRO (76.7%) or Vancouver (77.2%) definitions in predicting subsequent clinical relapse. The Houston definition was superior to the ASTRO definition in those treated both with and without AA and equivalent to the Vancouver definition in those receiving AA. The Houston definition demonstrated proportional hazards when categorized for the use of AA, unlike the ASTRO and Vancouver definitions. The effect of inadequate follow-up on the projected relapse rates was negligible with the Houston definition. The Houston relapse definition is favored after EBRT monotherapy or combined EBRT and AA. Use of the Cox proportional hazard multivariate analysis is appropriate with the Houston definition, but not with the ASTRO or Vancouver definitions if AA and non-AA patients are combined.
Development and calibration of a concept inventory to measure introductory college astronomy and physics students' understanding of Newtonian gravity

NASA Astrophysics Data System (ADS)

Williamson, Kathryn Elizabeth

The topic of Newtonian gravity offers a unique vantage point from which to investigate and encourage conceptual change because it is something with which everyone has daily experience, and because it is taught in two courses that reach a wide variety of students - introductory-level college astronomy ("Astro 101") and physics ("Phys 101"). Informed by the constructivist theory of learning, this study characterizes and measures Astro 101 and Phys 101 students' understanding of Newtonian gravity within four conceptual domains - Directionality, Force Law, Independence of Other Forces, and Threshold. A phenomenographic analysis of Astro 101 student-supplied responses to open-ended questions about gravity results in the characterization of students' alternative mental models and misapplications of the scientific model. These student difficulties inform the development of a multiple-choice assessment instrument, the Newtonian Gravity Concept Inventory (NGCI). Classical Test Theory (CTT) statistics, student interviews, and expert review show that the NGCI is a reliable and valid tool for assessing both Astro 101 and Phys 101 students' understanding of gravity. Furthermore, the NGCI can provide extensive and robust information about differences between Astro 101 and Phys 101 students and curricula. Comparing and contrasting the Astro 101 and Phys 101 CTT values and student response patterns shows qualitative differences in each of the four conceptual domains. Additionally, performing an Item Response Theory (IRT) analysis of NGCI student response data calibrates item parameters for all Astro 101 and Phys 101 courses and provides Newtonian gravity ability estimates for each student. Physics students show significantly higher pre-instruction and post-instruction IRT abilities than astronomy students, but they show approximately equal gains. To investigate the differential effect of Astro 101 compared to Phys 101 curricula on students' overall post-instruction Newtonian
Low-cost, highly transparent flexible low-e coating film to enable electrochromic windows with increased energy savings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berland, Brian; Hollingsworth, Russell

Five Quads of energy are lost through windows annually in the U.S. Low-e coatings are increasingly employed to reduce the wasted energy. Most commonly, the low-e coating is an oxide material applied directly to the glass at high temperature. With over 100,000,000 existing homes, a retrofit product is crucial to achieve widespread energy savings. Low-e films, i.e. coatings on polymeric substrates, are now also available to meet this need. However, the traditional oxide materials and process is incompatible with low temperature plastics. Alternate high performing low-e films typically incorporate materials that limit visible transmission to 35% or less. Further, themore » cost is high. The objective of this award was to develop a retrofit, integrated low-e/electrochromic window film to dramatically reduce energy lost through windows. While field testing of state-of-the-art electrochromic (EC) windows show the energy savings are maximized if a low-e coating is used in conjunction with the EC, available low-e films have a low visible transmission (~70% or less) that limits the achievable clear state and therefore, appearance and energy savings potential. Comprehensive energy savings models were completed at Lawrence Berkeley National Lab (LBNL). A parametric approach was used to project energy usage for windows with a large range of low-e properties across all U.S. climate zones, without limiting the study to materials that had already been produced commercially or made in a lab. The model enables projection of energy savings for low-e films as well as integrated low-e/EC products. This project developed a novel low-e film, optimized for compatibility with EC windows, using low temperature, high deposition rate processes for the growth of low-e coatings on plastic films by microwave plasma enhanced chemical vapor deposition. Silica films with good density and optical properties were demonstrated at deposition rates as high as 130Å/sec. A simple bi-layer low-e stack
Apolipoprotein E4 is associated with improved cognitive function in Amazonian forager-horticulturalists with a high parasite burden.

PubMed

Trumble, Benjamin C; Stieglitz, Jonathan; Blackwell, Aaron D; Allayee, Hooman; Beheim, Bret; Finch, Caleb E; Gurven, Michael; Kaplan, Hillard

2017-04-01

The apolipoprotein E4 (E4) allele is present worldwide, despite its associations with higher risk of cardiovascular morbidity, accelerated cognitive decline during aging, and Alzheimer 's disease (AD). The E4 allele is especially prevalent in some tropical regions with a high parasite burden. Equatorial populations also face a potential dual burden of high E4 prevalence combined with parasitic infections that can also reduce cognitive performance. We examined the interactions of E4, parasite burden, and cognitive performance in a traditional, nonindustrialized population of Amazonian forager-horticulturalists ( N = 372) to test whether E4 protects against cognitive decline in environments with a heavy pathogen burden. Contrary to observations in industrial populations, older adult E4 carriers with high parasite burdens either maintained or showed slight improvements in cognitive performance, whereas non-E4 carriers with a high parasite burden showed reduced cognitive performance. Being an E4 carrier is the strongest risk factor to date of AD and cognitive decline in industrial populations; it is associated with greater cognitive performance in individuals facing a high parasite and pathogen load, suggesting advantages to the E4 allele under certain environmental conditions. The current mismatch between postindustrial hygienic lifestyles and active parasite-rich environs may be critical for understanding genetic risk for cognitive aging.-Trumble, B. C., Stieglitz, J., Blackwell, A. D., Allayee, H., Beheim, B., Finch, C. E., Gurven, M., Kaplan, H. Apolipoprotein E4 is associated with improved cognitive function in Amazonian forager-horticulturalists with a high parasite burden. © FASEB.
Apolipoprotein E4 is associated with improved cognitive function in Amazonian forager-horticulturalists with a high parasite burden

PubMed Central

Trumble, Benjamin C.; Stieglitz, Jonathan; Blackwell, Aaron D.; Allayee, Hooman; Beheim, Bret; Finch, Caleb E.; Gurven, Michael; Kaplan, Hillard

2017-01-01

The apolipoprotein E4 (E4) allele is present worldwide, despite its associations with higher risk of cardiovascular morbidity, accelerated cognitive decline during aging, and Alzheimer’s disease (AD). The E4 allele is especially prevalent in some tropical regions with a high parasite burden. Equatorial populations also face a potential dual burden of high E4 prevalence combined with parasitic infections that can also reduce cognitive performance. We examined the interactions of E4, parasite burden, and cognitive performance in a traditional, nonindustrialized population of Amazonian forager-horticulturalists (N = 372) to test whether E4 protects against cognitive decline in environments with a heavy pathogen burden. Contrary to observations in industrial populations, older adult E4 carriers with high parasite burdens either maintained or showed slight improvements in cognitive performance, whereas non-E4 carriers with a high parasite burden showed reduced cognitive performance. Being an E4 carrier is the strongest risk factor to date of AD and cognitive decline in industrial populations; it is associated with greater cognitive performance in individuals facing a high parasite and pathogen load, suggesting advantages to the E4 allele under certain environmental conditions. The current mismatch between postindustrial hygienic lifestyles and active parasite-rich environs may be critical for understanding genetic risk for cognitive aging.—Trumble, B. C., Stieglitz, J., Blackwell, A. D., Allayee, H., Beheim, B., Finch, C. E., Gurven, M., Kaplan, H. Apolipoprotein E4 is associated with improved cognitive function in Amazonian forager-horticulturalists with a high parasite burden. PMID:28031319
Stereocontrolled generation of nucleophilic (Z)- or (E)-α-fluoroalkenylchromium reagents via carbon-fluorine bond activation: highly stereoselective synthesis of (E)- or (Z)-β-fluoroallylic alcohols.

PubMed

Nihei, Takashi; Yokotani, Saya; Ishihara, Takashi; Konno, Tsutomu

2014-02-14

Highly nucleophilic (Z)- or (E)-α-fluoroalkenylchromium species could be generated in a stereoselective manner via C-F bond activation of CBrF2-containing molecules, and they reacted smoothly with various aldehydes to give (E)- or (Z)-β-fluoroallylic alcohol derivatives in high yields, respectively.
Evander Childs High School. Career Exploration Opportunities for Bilingual Students, 1981-1982. O.E.E. Evaluation Report.

ERIC Educational Resources Information Center

Keyes, Jose Luis; And Others

The Career Exploration Opportunities for Bilingual Students (C.E.O.B.S.) program at Evander Childs High School in the Bronx, New York City, served 100 ninth and tenth grade Spanish speaking students of limited English proficiency during 1981-82. The project provided instruction in English as a second language and Spanish language skills; bilingual…
Birthday party

NASA Image and Video Library

2015-04-26

ISS043E142528 (04/26/2015) ---From the International Space Station NASA astronaut Terry Virts (right) tweeted this image of he and his crewmate Russian cosmonaut Anton Shkaplerov celebrating the birthday of ESA (European Space Agency) astronaut Samantha Cristoforetti (middle). His tweet commented: "Happy Birthday @AstroSamantha! We had a great time celebrating as a crew."
BEARCLAW: Boundary Embedded Adaptive Refinement Conservation LAW package

NASA Astrophysics Data System (ADS)

Mitran, Sorin

2011-04-01

The BEARCLAW package is a multidimensional, Eulerian AMR-capable computational code written in Fortran to solve hyperbolic systems for astrophysical applications. It is part of AstroBEAR, a hydrodynamic & magnetohydrodynamic code environment designed for a variety of astrophysical applications which allows simulations in 2, 2.5 (i.e., cylindrical), and 3 dimensions, in either cartesian or curvilinear coordinates.
A Bibliography of Aerospace Books and Teaching Aids for Secondary School Students and Teachers

DTIC Science & Technology

1961-11-13

p., llus.. HEim-E5. KENNETH. A.N ADVENTURE IN ASTRO.NOMY. 19539. $2.50. An introduction to radio astrono )my Viking. 127 1P.. illus.. 1958. $3.30...8217. ASTRONO )MY. Watts. 2:A; l., illus.. 1960. outer Si1-Pe. 14.5. The history of astronomy, the development Mt-rz,. lai.tyl. Tilns IS OUTER SPACE
Astrophysics

Science.gov Websites

, microquasars, neutron stars, pulsars, black holes astro-ph.IM - Instrumentation and Methods for Astrophysics Astrophysics. Methods for data analysis, statistical methods. Software, database design astro-ph.SR - Solar and
High resolution spectroscopy of the 12Lambda B hypernucleus produced by the (e,e'K+) reaction.

PubMed

Miyoshi, T; Sarsour, M; Yuan, L; Zhu, X; Ahmidouch, A; Ambrozewicz, P; Androic, D; Angelescu, T; Asaturyan, R; Avery, S; Baker, O K; Bertovic, I; Breuer, H; Carlini, R; Cha, J; Chrien, R; Christy, M; Cole, L; Danagoulian, S; Dehnhard, D; Elaasar, M; Empl, A; Ent, R; Fenker, H; Fujii, Y; Furic, M; Gan, L; Garrow, K; Gasparian, A; Gueye, P; Harvey, M; Hashimoto, O; Hinton, W; Hu, B; Hungerford, E; Jackson, C; Johnston, K; Juengst, H; Keppel, C; Lan, K; Liang, Y; Likhachev, V P; Liu, J H; Mack, D; Margaryan, A; Markowitz, P; Martoff, J; Mkrtchyan, H; Nakamura, S N; Petkovic, T; Reinhold, J; Roche, J; Sato, Y; Sawafta, R; Simicevic, N; Smith, G; Stepanyan, S; Tadevosyan, V; Takahashi, T; Tanida, K; Tang, L; Ukai, M; Uzzle, A; Vulcan, W; Wells, S; Wood, S; Xu, G; Yamaguchi, H; Yan, C

2003-06-13

High-energy, cw electron beams at new accelerator facilities allow electromagnetic production and precision study of hypernuclear structure, and we report here on the first experiment demonstrating the potential of the (e,e'K+) reaction for hypernuclear spectroscopy. This experiment is also the first to take advantage of the enhanced virtual photon flux available when electrons are scattered at approximately zero degrees. The observed energy resolution was found to be approximately 900 keV for the (12)(Lambda)B spectrum, and is substantially better than any previous hypernuclear experiment using magnetic spectrometers. The positions of the major excitations are found to be in agreement with a theoretical prediction and with a previous binding energy measurement, but additional structure is also observed in the core excited region, underlining the future promise of this technique.
What does it take to create an effective and interactive learning environment with 700 students in a college Gen. Ed. Astro Course?

NASA Astrophysics Data System (ADS)

Prather, Edward E.; Brissenden, G.; Cormier, S.; Eckenrode, J.; Collaboration of Astronomy Teaching Scholars CATS

2012-01-01

College-level general education (gen ed.) curricula in the US have many goals: exposing students to the breadth of human ideas; elevating their reading comprehension, writing abilities, critical reasoning skills; and providing an understanding of, and appreciation for, subjects outside of their chosen field of study. Unfortunately the majority of the teaching and learning for gen ed. courses takes place in large enrollment courses. In the wake of the recent US financial crisis, many institutions of higher learning face extreme budget cuts, leading many faculty to teach in substantially larger classes with increasingly fewer resources. At the University of Arizona this issue manifests itself in mega-classes with enrollments from 700-1400. We discuss key programmatic and pedagogical changes involved in successfully implementing proven collaborative learning strategies into an Astro 101 mega-class. From devising new ways to hand out and collect papers, to altering course seating, to outlawing cell phones and laptops, to implementing new ways of administering tests. We take a "what ever it takes” approach to engineering this mega-course environment so it can succeed as a learner-centered classroom. Paramount to the success of this course has been the creation of the new CAE Ambassadors program which advances the leadership role of prior non-science majors along the continuum from student, to teaching assistant, to science education researcher, to STEM minor. This material is based in part upon work supported by the National Science Foundation under Grant No. 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

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