Laboratory Testing and Performance Verification of the CHARIS Integral Field Spectrograph

NASA Technical Reports Server (NTRS)

Groff, Tyler D.; Chilcote, Jeffrey; Kasdin, N. Jeremy; Galvin, Michael; Loomis, Craig; Carr, Michael A.; Brandt, Timothy; Knapp, Gillian; Limbach, Mary Anne; Guyon, Olivier;

VizieR Online Data Catalog: CARMENES radial velocity curves of 7 M-dwarf (Trifonov+, 2018)

NASA Astrophysics Data System (ADS)

Trifonov, T.; Kuerster, M.; Zechmeister, M.; Tal-Or, L.; Caballero, J. A.; Quirrenbach, A.; Amado, P. J.; Ribas, I.; Reiners, A.; Reffert, S.; Dreizler, S.; Hatzes, A. P.; Kaminski, A.; Launhardt, R.; Henning, T.; Montes, D.; Bejar, V. J. S.; Mundt, R.; Pavlov, A.; Schmitt, J. H. M. M.; Seifert, W.; Morales, J. C.; Nowak, G.; Jeffers, S. V.; Rodriguez-Lopez, C.; Del Burgo, C.; Anglada-Escude, G.; Lopez-Santiago, J.; Mathar, R. J.; Ammler-von Eiff, M.; Guenther, E. W.; Barrado, D.; Gonzalez Hernandez, J. I.; Mancini, L.; Stuermer, J.; Abril, M.; Aceituno, J.; Alonso-Floriano, F. J.; Antona, R.; Anwand-Heerwart, H.; Arroyo-Torres, B.; Azzaro, M.; Baroch, D.; Bauer, F. F.; Becerril, S.; Benitez, D.; Berdinas, Z. M.; Bergond, G.; Bluemcke, M.; Brinkmoeller, M.; Cano, J.; Cardenas Vazquez, M. C.; Casal, E.; Cifuentes, C.; Claret, A.; Colome, J.; Cortes-Contreras, M.; Czesla, S.; Diez-Alonso, E.; Feiz, C.; Fernandez, M.; Ferro, I. M.; Fuhrmeister, B.; Galadi-Enriquez, D.; Garcia-Piquer, A.; Garcia Vargas, M. L.; Gesa, L.; Gomez Galera, V.; Gonzalez-Peinado, R.; Groezinger, U.; Grohnert, S.; Guardia, J.; Guijarro, A.; de Guindos, E.; Gutierrez-Soto, J.; Hagen, H.-J.; Hauschildt, P. H.; Hedrosa, R. P.; Helmling, J.; Hermelo, I.; Hernandez Arabi, R.; Hernandez Castano, L.; Hernandez Hernando, F.; Herrero, E.; Huber, A.; Huke, P.; Johnson, E.; de Juan, E.; Kim, M.; Klein, R.; Klueter, J.; Klutsch, A.; Lafarga, M.; Lampon, M.; Lara, L. M.; Laun, W.; Lemke, U.; Lenzen, R.; Lopez Del Fresno, M.; Lopez-Gonzalez, J.; Lopez-Puertas, M.; Lopez Salas, J. F.; Luque, R.; Magan Madinabeitia, H.; Mall, U.; Mandel, H.; Marfil, E.; Marin Molina, J. A.; Maroto Fernandez, D.; Martin, E. L.; Martin-Ruiz, S.; Marvin, C. J.; Mirabet, E.; Moya, A.; Moreno-Raya, M. E.; Nagel, E.; Naranjo, V.; Nortmann, L.; Ofir, A.; Oreiro, R.; Palle, E.; Panduro, J.; Pascual, J.; Passegger, V. M.; Pedraz, S.; Perez-Calpena, A.; Perez Medialdea, D.; Perger, M.; Perryman, M. A. C.; Pluto, M.; Rabaza, O.; Ramon, A.; Rebolo, R.; Redondo, P.; Reinhardt, S.; Rhode, P.; Rix, H.-W.; Rodler, F.; Rodriguez, E.; Rodriguez Trinidad, A.; Rohlo, R.-R.; Rosich, A.; Sadegi, S.; Sanchez-Blanco, E.; Sanchez Carrasco, M. A.; Sanchez-Lopez, A.; Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schaefer, S.; Schiller, J.; Schoefer, P.; Schweitzer, A.; Solano, E.; Stahl, O.; Strachan, J. B. P.; Suarez, J. C.; Tabernero, H. M.; Tala, M.; Tulloch, S. M.; Veredas, G.; Vico Linares, J. I.; Vilardel, F.; Wagner, K.; Winkler, J.; Woltho, V.; Xu, W.; Yan, F.; Zapatero Osorio, M. R.

2017-10-01

The two CARMENES spectrographs are grism cross-dispersed, white pupil, echelle spectrograph working in quasi-Littrow mode using a two-beam, two-slice image slicer. The visible spectrograph covers the wavelength range from 0.52um to 1.05um with 61 orders, a resolving power of R=94600, and a mean sampling of 2.8 pixels per resolution element. The data presented in this paper were taken during the early phase of operation of the CARMENES visible-light spectrograph. (8 data files).

Space telescope scientific instruments

NASA Technical Reports Server (NTRS)

Leckrone, D. S.

1979-01-01

The paper describes the Space Telescope (ST) observatory, the design concepts of the five scientific instruments which will conduct the initial observatory observations, and summarizes their astronomical capabilities. The instruments are the wide-field and planetary camera (WFPC) which will receive the highest quality images, the faint-object camera (FOC) which will penetrate to the faintest limiting magnitudes and achieve the finest angular resolution possible, and the faint-object spectrograph (FOS), which will perform photon noise-limited spectroscopy and spectropolarimetry on objects substantially fainter than those accessible to ground-based spectrographs. In addition, the high resolution spectrograph (HRS) will provide higher spectral resolution with greater photometric accuracy than previously possible in ultraviolet astronomical spectroscopy, and the high-speed photometer will achieve precise time-resolved photometric observations of rapidly varying astronomical sources on short time scales.

Sounding Rocket Instrument Development at UAHuntsville/NASA MSFC

NASA Technical Reports Server (NTRS)

Kobayashi, Ken; Cirtain, Jonathan; Winebarger, Amy; Savage, Sabrina; Golub, Leon; Korreck, Kelly; Kuzin, Sergei; Walsh, Robert; DeForest, Craig; DePontieu, Bart;

First Light from the 4.3-meter Discovery Channel Telescope At Lowell Observatory

NASA Astrophysics Data System (ADS)

Hall, Jeffrey C.; Levine, S.

2013-01-01

Seven years after groundbreaking on July 12, 2005, the 4.3-meter Discovery Channel Telescope (DCT) is now complete and into commissioning. We obtained first light images in mid 2012 with a 4K x 4K CCD and have recently obtained our first images with the DCT's main camera, the 6K x 6K Large Monolithic Imager (LMI, see adjacent poster by Massey). We held a celebratory gala on July 21, 2012, in Flagstaff. The DCT's delivered image quality is regularly subarcsecond with near-uniform image quality across the FOV from zenith to >2 airmasses, although we have not fully commissioned the active optics system. We attribute this to the outstanding quality of the mirror figures, performed by the University of Arizona's College of Optical Sciences (for M1) and L3 Brashear (for M2). The instrument cube at the RC focus can accommodate four instruments plus the LMI. Designed and built at Lowell Observatory, the cube also contains the DCT's autoguider and wavefront sensor. First light instruments include the 4000 DeVeny spectrograph (the former KPNO White Spectrograph), a low-resolution, high-throughput IR spectrograph, and a higher-resolution IR spectrograph/imager being built by Goddard Space Flight Center in collaboration with the University of Maryland. We are seeking funding for long-slit and fiber-fed echelle spectrographs for higher resolution optical spectroscopy. The DCT can also be configured to host Nasmyth and prime focus instruments. Discovery Communications and its founder John Hendricks contributed $16M to the $53M cost of the telescope, in return for naming rights and first rights to public, educational use of images in their programming. Analysis of data and publication by astronomers in professional journals follows the same procedure as for any other major telescope facility. Discovery's first DCT feature, "Scanning the Skies," aired on September 9, 2012. Future outreach plans include initiating webcasts to classrooms via the Discovery Education networks, reaching 30-40M schoolchildren across the USA. The DCT partner consortium includes Boston University (in perpetuity), the University of Maryland, and the University of Toledo, all of whom have ongoing, long term access to the facility.

An overview of instrumentation for the Large Binocular Telescope

NASA Astrophysics Data System (ADS)

Wagner, R. Mark

2010-07-01

An overview of instrumentation for the Large Binocular Telescope is presented. Optical instrumentation includes the Large Binocular Camera (LBC), a pair of wide-field (27 × 27) mosaic CCD imagers at the prime focus, and the Multi-Object Double Spectrograph (MODS), a pair of dual-beam blue-red optimized long-slit spectrographs mounted at the straight-through F/15 Gregorian focus incorporating multiple slit masks for multi-object spectroscopy over a 6 field and spectral resolutions of up to 8000. Infrared instrumentation includes the LBT Near-IR Spectroscopic Utility with Camera and Integral Field Unit for Extragalactic Research (LUCIFER), a modular near-infrared (0.9-2.5 μm) imager and spectrograph pair mounted at a bent interior focal station and designed for seeing-limited (FOV: 4 × 4) imaging, long-slit spectroscopy, and multi-object spectroscopy utilizing cooled slit masks and diffraction limited (FOV: 0.5 × 0.5) imaging and long-slit spectroscopy. Strategic instruments under development for the remaining two combined focal stations include an interferometric cryogenic beam combiner with near-infrared and thermal-infrared instruments for Fizeau imaging and nulling interferometry (LBTI) and an optical bench near-infrared beam combiner utilizing multi-conjugate adaptive optics for high angular resolution and sensitivity (LINC-NIRVANA). In addition, a fiber-fed bench spectrograph (PEPSI) capable of ultra high resolution spectroscopy and spectropolarimetry (R = 40,000-300,000) will be available as a principal investigator instrument. The availability of all these instruments mounted simultaneously on the LBT permits unique science, flexible scheduling, and improved operational support. Over the past two years the LBC and the first LUCIFER instrument have been brought into routine scientific operation and MODS1 commissioning is set to begin in the fall of 2010.

A Cross-Dispersed Medium-Resolution Spectrograph for Appalachian State Univeristy's 32-inch Telescope

NASA Astrophysics Data System (ADS)

Kluttz, K. A.; Gray, R. O.

2003-12-01

We have designed and constructed an economical medium-resolution spectrograph to be used on the 32-inch telescope of Appalachian State University's Dark Sky Observatory (DSO). The primary function of this instrument will be to study shell and emission-line stars. However, we will also use this instrument for chemical abundance studies and radial velocities. The basic design is that of an Ebert spectrograph with a single 6-inch mirror acting as both the collimator and camera. The primary dispersion is accomplished by a reflection grating, and order separation is accomplished by a grism. The spectrograph has been designed so that three wavelength regions are simultaneously imaged on the CCD camera. When the Hα line is centered in the third order, Hβ and lines of Fe II multiplet 42 -- often enhanced in shell and emission-line stars -- appear in the fourth order and the fifth order contains both the Ca II K & H lines. To facilitate abundance measurements, a telluric-free region near 6400Å is available in the third order by tilting the main diffraction grating. Preliminary tests have shown that the resolution of the new spectrograph is 0.42Å in the third order (R ≈ 15,000). This relatively high resolution will allow studies to be conducted at DSO which have not previously been possible with the instrumentation currently in use. Several optical components for this spectrograph were purchased with grants from the Fund for Astrophysical Research and the University Research Council.

Opto-mechanical design of an image slicer for the GRIS spectrograph at GREGOR

NASA Astrophysics Data System (ADS)

Vega Reyes, N.; Esteves, M. A.; Sánchez-Capuchino, J.; Salaun, Y.; López, R. L.; Gracia, F.; Estrada Herrera, P.; Grivel, C.; Vaz Cedillo, J. J.; Collados, M.

2016-07-01

An image slicer has been proposed for the Integral Field Spectrograph [1] of the 4-m European Solar Telescope (EST) [2] The image slicer for EST is called MuSICa (Multi-Slit Image slicer based on collimator-Camera) [3] and it is a telecentric system with diffraction limited optical quality offering the possibility to obtain high resolution Integral Field Solar Spectroscopy or Spectro-polarimetry by coupling a polarimeter after the generated slit (or slits). Considering the technical complexity of the proposed Integral Field Unit (IFU), a prototype has been designed for the GRIS spectrograph at GREGOR telescope at Teide Observatory (Tenerife), composed by the optical elements of the image slicer itself, a scanning system (to cover a larger field of view with sequential adjacent measurements) and an appropriate re-imaging system. All these subsystems are placed in a bench, specially designed to facilitate their alignment, integration and verification, and their easy installation in front of the spectrograph. This communication describes the opto-mechanical solution adopted to upgrade GRIS while ensuring repeatability between the observational modes, IFU and long-slit. Results from several tests which have been performed to validate the opto-mechanical prototypes are also presented.

ZTF Bright Transient Survey classifications

NASA Astrophysics Data System (ADS)

Graham, M. L.; Bellm, E.; Bektesevic, D.; Eadie, G.; Huppenkothen, D.; Davenport, J. R. A.; Fremling, C.; Sharma, Y.; Kulkarni, S. R.; Walters, R.; Blagorodnova, N.; Neill, J.; Miller, A. A.; Taddia, F.; Lunnan, R.; Taggart, K.; Perley, D. A.; Goobar, A.

2018-06-01

The Zwicky Transient Facility (ZTF; ATel #11266) Bright Transient Survey (BTS; ATel #11688) reports classifications of the following targets. Spectra have been obtained with the Dual Imaging Spectrograph (range 340-1000nm, spectral resolution R 1000) mounted on the 3.5m telescope at Apache Point Observatory, the Spectral Energy Distribution Machine (SEDM) (range 350-950nm, spectral resolution R 100) mounted on the Palomar 60-inch (P60) telescope (Blagorodnova et. al. 2018, PASP, 130, 5003), or the Andalucia Faint Object Spectrograph and Camera (ALFOSC) on the 2.5m Nordic Optical Telescope (NOT).

Multi-object medium resolution optical spectroscopy at the E-ELT

NASA Astrophysics Data System (ADS)

Spanò, Paolo; Bonifacio, Piercarlo

2008-07-01

We present the design of a compact medium resolution spectrograph (R~15,000-20,000), intended to operate on a 42m telescope in seeing-limited mode. Our design takes full advantage of some new technology optical components, like volume phase holographic (VPH) gratings. At variance with the choice of complex large echelle spectrographs, which have been the standard on 8m class telescopes, we selected an efficient VPH spectrograph with a limited beam diameter, in order to keep overall dimensions and costs low, using proven available technologies. To obtain such a resolution, we need to moderately slice the telescope image plane onto the spectrograph entrance slit (5-6 slices). Then, standard telescope AO-mode (GLAO, Ground Layer Adaptive Optics) can be used over a large field of view (~10 arcmin), without loosing efficiency. Multiplex capabilities can greatly increase the observing efficiency. A robotic pick-up mirror system can be implemented, within conventional environmental conditions (temperature, pressure, gravity, size), demanding only standard mechanical and optical tolerances. A modular approach allows us scaling multiplex capabilities on overall costs and available space.

CHISL: the combined high-resolution and imaging spectrograph for the LUVOIR surveyor

NASA Astrophysics Data System (ADS)

France, Kevin; Fleming, Brian; Hoadley, Keri

2016-10-01

NASA is currently carrying out science and technical studies to identify its next astronomy flagship mission, slated to begin development in the 2020s. It has become clear that a Large Ultraviolet/Optical/IR (LUVOIR) surveyor mission (d≈12 m, Δλ≈1000 Å, 2 μm spectroscopic bandpass) can carry out the largest number of NASA's exoplanet and astrophysics science goals over the coming decades. The science grasp of an LUVOIR surveyor is broad, ranging from the direct detection of potential biomarkers on rocky planets to the flow of matter into and out of galaxies and the history of star-formation across cosmic time. There are technical challenges for several aspects of the LUVOIR surveyor concept, including component level technology readiness maturation and science instrument concepts for a broadly capable ultraviolet spectrograph. We present the scientific motivation for, and a preliminary design of, a multiplexed ultraviolet spectrograph to support both the exoplanet and astrophysics goals of the LUVOIR surveyor mission concept, the combined high-resolution and imaging spectrograph for the LUVOIR surveyor (CHISL). CHISL includes a high-resolution (R≈120,000 1000 to 1700 Å) point-source spectroscopy channel and a medium-resolution (R≥14,000 from 1000 to 2000 Å in a single observation and R˜24,000 to 35,000 in multiple grating settings) imaging spectroscopy channel. CHISL addresses topics ranging from characterizing the composition and structure of planet-forming disks to the feedback of matter between galaxies and the intergalactic medium. We present the CHISL concept, a small sample of representative science cases, and the primary technological hurdles. Technical challenges include high-efficiency ultraviolet coatings and high-quantum efficiency, large-format, photon counting detectors. We are actively engaged in laboratory and flight characterization efforts for all of these enabling technologies as components on sounding rocket payloads under development at the University of Colorado. We describe two payloads that are designed to be pathfinder instruments for the high-resolution (CHESS) and imaging spectroscopy (SISTINE) arms of CHISL. We are carrying out this instrument design, characterization, and flight-testing today to support the new start of an LUVOIR surveyor mission in the next decade.

An overview of instrumentation for the Large Binocular Telescope

NASA Astrophysics Data System (ADS)

Wagner, R. Mark

2012-09-01

An overview of instrumentation for the Large Binocular Telescope (LBT) is presented. Optical instrumentation includes the Large Binocular Camera (LBC), a pair of wide-field (27' x 27') mosaic CCD imagers at the prime focus, and the Multi-Object Double Spectrograph (MODS), a pair of dual-beam blue-red optimized long-slit spectrographs mounted at the left and right direct F/15 Gregorian foci incorporating multiple slit masks for multi-object spectroscopy over a 6' field and spectral resolutions of up to 2000. Infrared instrumentation includes the LBT Near-IR Spectroscopic Utility with Camera and Integral Field Unit for Extragalactic Research (LUCI), a modular near-infrared (0.9-2.5 μm) imager and spectrograph pair mounted at the left and right front bent F/15 Gregorian foci and designed for seeing-limited (FOV: 4' × 4') imaging, long-slit spectroscopy, and multiobject spectroscopy utilizing cooled slit masks and diffraction limited (FOV: 0'.5 × 0'.5) imaging and long-slit spectroscopy. Strategic instruments under development that can utilize the full 23-m baseline of the LBT include an interferometric cryogenic beam combiner with near-infrared and thermal-infrared instruments for Fizeau imaging and nulling interferometry (LBTI) and an optical bench near-infrared beam combiner utilizing multi-conjugate adaptive optics for high angular resolution and sensitivity (LINC-NIRVANA). LBTI is currently undergoing commissioning on the LBT and utilizing the installed adaptive secondary mirrors in both single- sided and two-sided beam combination modes. In addition, a fiber-fed bench spectrograph (PEPSI) capable of ultra high resolution spectroscopy and spectropolarimetry (R = 40,000-300,000) will be available as a principal investigator instrument. Over the past four years the LBC pair, LUCI1, and MODS1 have been commissioned and are now scheduled for routine partner science observations. The delivery of both LUCI2 and MODS2 is anticipated before the end of 2012. The availability of all these instruments mounted simultaneously on the LBT permits unique science, flexible scheduling, and improved operational support.

The mechanical design of CHARIS: an exoplanet IFS for the Subaru Telescope

NASA Astrophysics Data System (ADS)

Galvin, Michael B.; Carr, Michael A.; Groff, Tyler D.; Kasdin, N. Jeremy; Fagan, Radford; Hayashi, Masahiko; Takato, Naruhisa

2014-07-01

Princeton University is designing and building an integral field spectrograph (IFS), the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS), for integration with the Subaru Corona Extreme Adaptive Optics (SCExAO) system and the AO188 adaptive optics system on the Subaru Telescope. CHARIS and SCExAO will measure spectra of hot, young Jovian planets in a coronagraphic image across J, H, and K bands down to an 80 milliarcsecond inner working angle. Here we present the current status of the mechanical design of the CHARIS instrument.

Performance, results, and prospects of the visible spectrograph VEGA on CHARA

NASA Astrophysics Data System (ADS)

Mourard, Denis; Challouf, Mounir; Ligi, Roxanne; Bério, Philippe; Clausse, Jean-Michel; Gerakis, Jérôme; Bourges, Laurent; Nardetto, Nicolas; Perraut, Karine; Tallon-Bosc, Isabelle; McAlister, H.; ten Brummelaar, T.; Ridgway, S.; Sturmann, J.; Sturmann, L.; Turner, N.; Farrington, C.; Goldfinger, P. J.

2012-07-01

In this paper, we review the current performance of the VEGA/CHARA visible spectrograph and make a review of the most recent astrophysical results. The science programs take benefit of the exceptional angular resolution, the unique spectral resolution and one of the main features of CHARA: Infrared and Visible parallel operation. We also discuss recent developments concerning the tools for the preparation of observations and important features of the data reduction software. A short discussion of the future developments will complete the presentation, directed towards new detectors and possible new beam combination scheme for improved sensitivity and imaging capabilities.

Cassini UVIS Auroral Observations in 2016 and 2017

NASA Astrophysics Data System (ADS)

Pryor, Wayne R.; Esposito, Larry W.; Jouchoux, Alain; Radioti, Aikaterini; Grodent, Denis; Gustin, Jacques; Gerard, Jean-Claude; Lamy, Laurent; Badman, Sarah; Dyudina, Ulyana A.; Cassini UVIS Team, Cassini VIMS Team, Cassini ISS Team, HST Saturn Auroral Team

2017-10-01

In 2016 and 2017, the Cassini Saturn orbiter executed a final series of high-inclination, low-periapsis orbits ideal for studies of Saturn's polar regions. The Cassini Ultraviolet Imaging Spectrograph (UVIS) obtained an extensive set of auroral images, some at the highest spatial resolution obtained during Cassini's long orbital mission (2004-2017). In some cases, two or three spacecraft slews at right angles to the long slit of the spectrograph were required to cover the entire auroral region to form auroral images. We will present selected images from this set showing narrow arcs of emission, more diffuse auroral emissions, multiple auroral arcs in a single image, discrete spots of emission, small scale vortices, large-scale spiral forms, and parallel linear features that appear to cross in places like twisted wires. Some shorter features are transverse to the main auroral arcs, like barbs on a wire. UVIS observations were in some cases simultaneous with auroral observations from the Cassini Imaging Science Subsystem (ISS) the Cassini Visual and Infrared Mapping Spectrometer (VIMS), and the Hubble Space Telescope Space Telescope Imaging Spectrograph (STIS) that will also be presented.

High-Speed Laser Imaging, Emission and Temperature Measurements of Explosions

DTIC Science & Technology

2006-09-01

of these optical fibers illuminated the entrance slit of a dedicated Ocean Optics model HR-2000 spectrograph. The seven spectrographs were modified...Hewlett-Packard). The spectral response of the system was calibrated using an ARC Model XS432 Xenon lamp. Time resolution is approximately 12...F FOROHAR 101 STRAUSS AVE INDIAN HEAD MD 20640-5035 1 NAVAL SURFACE WARFARE CTR CODE 920J R GUIRGUIS 101 STRAUSS AVE INDIAN

S4EI (Spectral Sampling with Slicer for Stellar and Extragalactical Instrumentation), a new-generation of 3D spectro-imager dedicated to night astronomy

NASA Astrophysics Data System (ADS)

Sayède, Frédéric; Puech, Mathieu; Mein, Pierre; Bonifacio, Piercarlo; Malherbe, Jean-Marie; Galicher, Raphaël.; Amans, Jean-Philippe; Fasola, Gilles

2014-07-01

Multichannel Subtractive Double Pass (MSDP) spectrographs have been widely used in solar spectroscopy because of their ability to provide an excellent compromise between field of view and spatial and spectral resolutions. Compared with other types of spectrographs, MSDP can deliver simultaneous monochromatic images at higher spatial and spectral resolutions without any time-scanning requirement (as with Fabry-Perot spectrographs), and with limited loss of flux. These performances are obtained thanks to a double pass through the dispersive element. Recent advances with VPH (Volume phase holographic) Grisms as well as with image slicers now make MSDP potentially sensitive to much smaller fluxes. We present S4EI (Spectral Sampling with Slicer for Stellar and Extragalactical Instrumentation), which is a new concept for extending MSDP to night-time astronomy. It is based on new generation reflecting plane image slicers working with large apertures specific to night-time telescopes. The resulting design could be potentially very attractive and innovative for different domains of astronomy, e.g., the simultaneous spatial mapping of accurately flux-calibrated emission lines between OH sky lines in extragalactic astronomy or the simultaneous imaging of stars, exoplanets and interstellar medium. We present different possible MSDP/S4EI configurations for these science cases and expected performances on telescopes such as the VLT.

The Interface Region Imaging Spectrograph (IRIS) Small Explorer

NASA Astrophysics Data System (ADS)

de Pontieu, B.; Title, A. M.; Schryver, C. J.; Lemen, J. R.; Golub, L.; Kankelborg, C. C.; Carlsson, M.

2009-12-01

The Interface Region Imaging Spectrograph (IRIS) was recently selected as a small explorer mission by NASA. The primary goal of IRIS is to understand how the solar atmosphere is energized. The IRIS investigation combines advanced numerical modeling with a high resolution 20 cm UV imaging spectrograph that will obtain spectra covering temperatures from 4,500 to 10 MK in three wavelength ranges (1332-1358 Angstrom, 1390-1406 Angstrom and 2785-2835 Angstrom) and simultaneous images covering temperatures from 4,500 K to 65,000 K. IRIS will obtain UV spectra and images with high resolution in space (1/3 arcsec) and time (1s) focused on the chromosphere and transition region of the Sun, a complex dynamic interface region between the photosphere and corona. In this region, all but a few percent of the non-radiative energy leaving the Sun is converted into heat and radiation. IRIS fills a crucial gap in our ability to advance Sun-Earth connection studies by tracing the flow of energy and plasma through this foundation of the corona and heliosphere. The IRIS investigation is led by PI Alan Title (LMSAL) with major participation by the Harvard Smithsonian Astrophysical Observatory, Montana State University, NASA Ames Research Center, Stanford University and the University of Oslo (Norway). IRIS is scheduled for launch in late 2012, and will have a nominal two year mission lifetime.

NOAO's next-generation optical spectrograph

NASA Astrophysics Data System (ADS)

Barden, Samuel C.; Harmer, Charles F.; Blakley, Rick D.; Parks, Rachel J.

2000-08-01

The National Optical Astronomy Observatory is developing a new, wide-field, imaging spectrograph for use on its existing 4-meter telescopes. This Next Generation Optical Spectrograph (NGOS) will utilize volume-phase holographic grating technology and will have a mosaiced detector array to image the spectra over a field of view that will be something like 10.5 by 42 arc-minutes on the sky. The overall efficiency of the spectrograph should be quite high allowing it to outperform the current RC spectrograph by factors of 10 to 20 and the Hydra multi-fiber instrument by a facto of fiber to ten per object. The operational range of the instrument will allow observations within the optical and near-IR regions. Spectral resolutions will go from R equals 1000 to at least R equals 5000 with 1.4 arc-second slits. The large size of this instrument, with a beam diameter of 200 mm and an overall length of nearly 3 meters, presents a significant challenge in mounting it at the Cassegrain location of the telescope. Design trades and options that allow it to fit are discussed.

The Optical Design of CHARIS: An Exoplanet IFS for the Subaru Telescope

NASA Technical Reports Server (NTRS)

Peters-Limbach, Mary; Groff, Tyler; Kasdin, N. Jeremy; Driscoll, Dave; Galvin, Michael; Foster, Allen; Carr, Michael; LeClerc, Dave; Fagan, Rad; McElwain, Michael;

CHISL: the combined high-resolution and imaging spectrograph for the LUVOIR surveyor

NASA Astrophysics Data System (ADS)

France, Kevin; Fleming, Brian; Hoadley, Keri

2016-07-01

NASA is currently carrying out science and technical studies to identify its next astronomy flagship mission, slated to begin development in the 2020s. It has become clear that a Large Ultraviolet/Optical/IR (LUVOIR) Surveyor mission (dprimary ≍ 12 m, Δλ ≍ 1000 Å - 2 μm spectroscopic bandpass) can carry out the largest number of NASA's exoplanet and astrophysics science goals over the coming decades. The science grasp of a LUVOIR Surveyor is broad, ranging from the direct detection of potential biomarkers on rocky planets to the flow of matter into and out of galaxies and the history of star-formation across cosmic time. There are technical challenges for several aspects of the LUVOIR Surveyor concept, including component level technology readiness maturation and science instrument concepts for a broadly capable ultraviolet spectrograph. We present the scientific motivation for, and a preliminary design of, a multiplexed ultraviolet spectrograph to support both the exoplanet and astrophysics goals of the LUVOIR Surveyor mission concept, the Combined High-resolution and Imaging Spectrograph for the LUVOIR Surveyor (CHISL). CHISL includes a highresolution (R ≍ 120,000; 1000 - 1700Å) point-source spectroscopy channel and a medium resolution (R >= 14,000 from 1000 - 2000 Å in a single observation and R 24,000 - 35,000 in multiple grating settings) imaging spectroscopy channel. CHISL addresses topics ranging from characterizing the composition and structure of planet-forming disks to the feedback of matter between galaxies and the intergalactic medium. We present the CHISL concept, a small sample of representative science cases, and the primary technological hurdles. Technical challenges include high-efficiency ultraviolet coatings and high-quantum efficiency, large-format, photon counting detectors. We are actively engaged in laboratory and flight characterization efforts for all of these enabling technologies as components on sounding rocket payloads under development at the University of Colorado. We describe two payloads that are designed to be pathfinder instruments for the high-resolution (CHESS) and imaging spectroscopy (SISTINE) arms of CHISL. We are carrying out this instrument design, characterization, and flight-testing today to support the new start of a LUVOIR Surveyor mission in the next decade.

Multiplexing 32,000 spectra onto 8 detectors: the HARMONI field splitting, image slicing, and wavelength selecting optics

NASA Astrophysics Data System (ADS)

Tecza, Matthias; Thatte, Niranjan; Clarke, Fraser; Freeman, David; Kosmalski, Johan

2012-09-01

HARMONI, the High Angular Resolution Monolithic Optical & Near-infrared Integral field spectrograph is one of two first-light instruments for the European Extremely Large Telescope. Over a 256x128 pixel field-of-view HARMONI will simultaneously measure approximately 32,000 spectra. Each spectrum is about 4000 spectral pixels long, and covers a selectable part of the 0.47-2.45 μm wavelength range at resolving powers of either R≍4000, 10000, or 20000. All 32,000 spectra are imaged onto eight HAWAII4RG detectors using a multiplexing scheme that divides the input field into four sub-fields, each imaged onto one image slicer that in turn re-arranges a single sub-field into two long exit slits feeding one spectrograph each. In total we require eight spectrographs, each with one HAWAII4RG detector. A system of articulated and exchangeable fold-mirrors and VPH gratings allows one to select different spectral resolving powers and wavelength ranges of interest while keeping a fixed geometry between the spectrograph collimator and camera avoiding the need for an articulated grating and camera. In this paper we describe both the field splitting and image slicing optics as well as the optics that will be used to select both spectral resolving power and wavelength range.

The Fundamental Structure of Coronal Loops

NASA Technical Reports Server (NTRS)

Winebarger, Amy; Warren, Harry; Cirtain, Jonathan; Kobayashi, Ken; Korreck, Kelly; Golub, Leon; Kuzin, Sergey; Walsh, Robert; DePontieu, Bart; Title, Alan;

Collimating slicer for optical integral field spectroscopy

NASA Astrophysics Data System (ADS)

Laurent, Florence; Hénault, François

2016-07-01

Integral Field Spectroscopy (IFS) is a technique that gives simultaneously the spectrum of each spatial sampling element of a given field. It is a powerful tool which rearranges the data cube represented by two spatial dimensions defining the field and the spectral decomposition (x, y, λ) in a detector plane. In IFS, the "spatial" unit reorganizes the field, the "spectral" unit is being composed of a classical spectrograph. For the spatial unit, three main techniques - microlens array, microlens array associated with fibres and image slicer - are used in astronomical instrumentations. The development of a Collimating Slicer is to propose a new type of optical integral field spectroscopy which should be more compact. The main idea is to combine the image slicer with the collimator of the spectrograph mixing the "spatial" and "spectral" units. The traditional combination of slicer, pupil and slit elements and spectrograph collimator is replaced by a new one composed of a slicer and spectrograph collimator only. After testing few configurations, this new system looks very promising for low resolution spectrographs. In this paper, the state of art of integral field spectroscopy using image slicers will be described. The new system based onto the development of a Collimating Slicer for optical integral field spectroscopy will be depicted. First system analysis results and future improvements will be discussed.

VizieR Online Data Catalog: Texas-Oxford NVSS (TONS) radio galaxies (Brand+, 2005)

NASA Astrophysics Data System (ADS)

Brand, K.; Rawlings, S.; Hill, G. J.; Tufts, J. R.

2005-10-01

Optical spectra were obtained during the period 2000 October-2003 May on the 2.6-m Nordic Optical Telescope (NOT) using the Andalucia faint object spectrograph, the 4.2-m William Herschel telescope (WHT) using ISIS, the 2.7-m Smith reflector at McDonald with the Imaging Grism Instrument (IGI), and the Hobby-Eberly Telescope (HET) using the Marcario low-resolution spectrograph (LRS). (3 data files).

The Ultraviolet Spectrograph on NASA's Juno Mission

NASA Astrophysics Data System (ADS)

Gladstone, G. Randall; Persyn, Steven C.; Eterno, John S.; Walther, Brandon C.; Slater, David C.; Davis, Michael W.; Versteeg, Maarten H.; Persson, Kristian B.; Young, Michael K.; Dirks, Gregory J.; Sawka, Anthony O.; Tumlinson, Jessica; Sykes, Henry; Beshears, John; Rhoad, Cherie L.; Cravens, James P.; Winters, Gregory S.; Klar, Robert A.; Lockhart, Walter; Piepgrass, Benjamin M.; Greathouse, Thomas K.; Trantham, Bradley J.; Wilcox, Philip M.; Jackson, Matthew W.; Siegmund, Oswald H. W.; Vallerga, John V.; Raffanti, Rick; Martin, Adrian; Gérard, J.-C.; Grodent, Denis C.; Bonfond, Bertrand; Marquet, Benoit; Denis, François

2017-11-01

The ultraviolet spectrograph instrument on the Juno mission (Juno-UVS) is a long-slit imaging spectrograph designed to observe and characterize Jupiter's far-ultraviolet (FUV) auroral emissions. These observations will be coordinated and correlated with those from Juno's other remote sensing instruments and used to place in situ measurements made by Juno's particles and fields instruments into a global context, relating the local data with events occurring in more distant regions of Jupiter's magnetosphere. Juno-UVS is based on a series of imaging FUV spectrographs currently in flight—the two Alice instruments on the Rosetta and New Horizons missions, and the Lyman Alpha Mapping Project on the Lunar Reconnaissance Orbiter mission. However, Juno-UVS has several important modifications, including (1) a scan mirror (for targeting specific auroral features), (2) extensive shielding (for mitigation of electronics and data quality degradation by energetic particles), and (3) a cross delay line microchannel plate detector (for both faster photon counting and improved spatial resolution). This paper describes the science objectives, design, and initial performance of the Juno-UVS.

VizieR Online Data Catalog: PS1 z>5.6 quasars follow-up (Banados+, 2016)

NASA Astrophysics Data System (ADS)

Banados, E.; Venemans, B. P.; Decarli, R.; Farina, E. P.; Mazzucchelli, C.; Walter, F.; Fan, X.; Stern, D.; Schlafly, E.; Chambers, K. C.; Rix, H.-W.; Jiang, L.; McGreer, I.; Simcoe, R.; Wang, F.; Yang, J.; Morganson, E.; De Rosa, G.; Greiner, J.; Balokovic, M.; Burgett, W. S.; Cooper, T.; Draper, P. W.; Flewelling, H.; Hodapp, K. W.; Jun, H. D.; Kaiser, N.; Kudritzki, R.-P.; Magnier, E. A.; Metcalfe, N.; Miller, D.; Schindler, J.-T.; Tonry, J. L.; Wainscoat, R. J.; Waters, C.; Yang, Q.

2017-01-01

The photometric follow-up observations were carried out over different observing runs and different instruments. We obtained optical and near-infrared images with the MPG 2.2m/GROND, New Technology Telescope (NTT)/EFOSC2, NTT/SofI, Calar Alto (CAHA) 3.5m/Omega2000, CAHA 2.2m/CAFOS21, MMT/SWIRC), and du Pont/Retrocam; see Table 1 for details of the observations and filters used. A spectroscopic campaign was carried out using several instruments at different telescopes: EFOSC2 at the NTT telescope in La Silla, the Focal Reducer / Low-Dispersion Spectrograph 2 (FORS2) at the Very Large Telescope (VLT), the Folded-Port Infrared Echellette (FIRE) spectrometer and the Low-Dispersion Survey Spectrograph (LDSS3) at the Baade and Clay Telescopes at Las Campanas Observatory, the Low-Resolution Imaging Spectrometer (LRIS) at the Keck I 10m Telescope on Mauna Kea, the Double Spectrograph (DBSP) on the 200 inch (5m) Hale Telescope at Palomar Observatory (P200), the Red-Channel Spectrograph on the 6.5m MMT Telescope, the Cassegrain TWIN Spectrograph at the 3.5m Calar Alto Telescope (CAHA 3.5m), and the Multi-object Double Spectrograph (MODS) and LUCI spectrograph at the Large Binocular Telescope (LBT). The details of the spectroscopic observations of the PS1-discovered quasars are shown in Table 5. (10 data files).

GMTIFS: The Giant Magellan Telescope integral fields spectrograph and imager

NASA Astrophysics Data System (ADS)

Sharp, Rob; Bloxham, G.; Boz, R.; Bundy, D.; Davies, J.; Espeland, B.; Fordham, B.; Hart, J.; Herrald, N.; Nielsen, J.; Vaccarella, A.; Vest, C.; Young, P.; McGregor, P.

2016-08-01

GMTIFS is the first-generation adaptive optics integral-field spectrograph for the GMT, having been selected through a competitive review process in 2011. The GMTIFS concept is for a workhorse single-object integral-field spectrograph, operating at intermediate resolution (R 5,000 and 10,000) with a parallel imaging channel. The IFS offers variable spaxel scales to Nyquist sample the diffraction limited GMT PSF from λ 1-2.5 μm as well as a 50 mas scale to provide high sensitivity for low surface brightness objects. The GMTIFS will operate with all AO modes of the GMT (Natural guide star - NGSAO, Laser Tomography - LTAO, and, Ground Layer - GLAO) with an emphasis on achieving high sky coverage for LTAO observations. We summarize the principle science drivers for GMTIFS and the major design concepts that allow these goals to be achieved.

Development and Flight-testing of Astronomical Instrumentation for Future NASA Astrophysics Missions

NASA Astrophysics Data System (ADS)

France, Kevin

We propose a four year suborbital research program to continue the University of Colorado's efforts in the development and flight testing of instrument designs and critical path technologies for ultraviolet spectroscopy in support of future NASA Explorer, Probe-, and Flagship-class missions. This proposal builds on our existing program of high-resolution spectroscopy for the 100 - 160 nm bandpass with the development of a new high-efficiency imaging spectrograph operating in the same band. The ultimate goal of the University of Colorado ultraviolet rocket program is to develop the technical capabilities to enable a future, highly multiplexed ultraviolet spectrograph (with both high-resolution and imaging spectroscopy modes), e.g., an analog to the successful HST-STIS instrument, with an order-of-magnitude higher efficiency. We do this in the framework of a university led program where undergraduate, graduate, and postdoctoral training is paramount and cutting edge science investigations support our baseline technology development program. In the proposed effort, we will optimize our high-resolution (R > 100,000) echelle spectrograph payload (CHESS) with the first science flight of a new, large-format CCD array provided by our collaborators at JPL and Arizona State University. We will launch CHESS to study our local interstellar environment with spectral resolving power and bandpass that cannot be achieved with any suite of current or planned space missions. In parallel with the proposed science flights of CHESS, we will design, calibrate, and launch a new high-throughput imaging spectrograph (SISTINE); the first sub-arcsecond imaging, medium spectral resolution (R = 10,000), spectrograph ever flown with spectral coverage over the entire 100 - 160 nm bandpass. SISTINE incorporates several novel optical technologies that were highlighted as major hardware drivers for NASA's next large ultraviolet/optical/near-IR observatory by the 2014 Cosmic Origins Technology Report, including advanced mirror coatings with high broadband reflectivity (including > 20% efficiency gains below 115 nm), the first demonstration and flight test of these coatings on a shaped 0.5-meter telescope, and large-format, high-QE photon counting detectors. SISTINE will be launched to study the energetic radiation environment in the habitable zones around nearby low-mass exoplanet host stars, systems that are the top priority in NASA's search for the signatures of biological activity in the coming decade. SISTINE addresses the highest science priority in the 2010 Astronomy and Astrophysics Decadal Survey and is a crucial step towards meeting NASA's technology needs for future space observatories.

Ohio State Infrared Imager/Spectrograph (OSIRIS) | SOAR

Science.gov Websites

opperate at wavelengths from 0.9 to 2.4 microns. Internal optics allow for two plate scales and a variety of spectroscopic resolutions. Internal mechanisms control the selected filter, focal plane mask

Wavefront control methods for high-contrast integral field spectroscopy

NASA Astrophysics Data System (ADS)

Groff, Tyler D.; Mejia Prada, Camilo; Cady, Eric; Rizzo, Maxime J.; Mandell, Avi; Gong, Qian; McElwain, Michael; Zimmerman, Neil; Saxena, Prabal; Guyon, Olivier

2017-09-01

Direct Imaging of exoplanets using a coronagraph has become a major field of research both on the ground and in space. Key to the science of direct imaging is the spectroscopic capabilities of the instrument, our ability to fit spectra, and understanding the composition of the observed planets. Direct imaging instruments generally use an integral field spectrograph (IFS), which encodes the spectrum into a two-dimensional image on the detector. This results in more efficient detection and characterization of targets, and the spectral information is critical to achieving detection limits below the speckle floor of the imager. The most mature application of these techniques is at more modest contrast ratios on ground-based telescopes, achieving approximately 5-6 orders of magnitude suppression. In space, where we are attempting to detect Earth-analogs, the contrast requirements are more severe and the IFS must be incorporated into the wavefront control loop to reach 1e-10 detection limits required for Earth-like planet detection. We present the objectives and application of IFS imagery for both a speckle control loop and post-processing of images. Results, tested methodologies, and the future work using the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) and the Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) at the JPL High Contrast Imaging Testbed are presented.

SPARTAN Near-IR Camera | SOAR

Science.gov Websites

SPARTAN Near-IR Camera SPARTAN Cookbook Ohio State Infrared Imager/Spectrograph (OSIRIS) - NO LONGER Instrumentation at SOAR»SPARTAN Near-IR Camera SPARTAN Near-IR Camera System Overview The Spartan Infrared Camera is a high spatial resolution near-IR imager. Spartan has a focal plane conisisting of four "

Deriving Temperatures from the Homopause of Jupiter

NASA Astrophysics Data System (ADS)

Kim, Sang J.

2015-11-01

Recently, Kim et al. (Icarus, 2015) derived homopause temperatures from several places on the north and south polar regions of Jupiter by analyzing the 3-μm spectro-images of CH4, which were obtained using the Gemini Near-Infrared Spectrograph (GNIRS). The spectral resolution of the data was R~18,000, which is enough to resolve the sharp 3-μm emission lines of the P and Q branches of CH4. From the next year’s JUNO encounter with Jupiter, we are expecting low resolution spectra from JUNO’s IR 2-5 μm spectrograph, whose resolution is only R~300 at 3 μm. We will present a method to derive homopause temperatures from low-resolution spectra utilizing the gross envelopes of the P, Q, R branch lines of CH4. We will discuss possible sciences extracted from the constructed maps of homopause temperatures over the auroral or non-auroral regions of Jupiter.

An overview and the current status of instrumentation at the Large Binocular Telescope Observatory

NASA Astrophysics Data System (ADS)

Wagner, R. Mark; Edwards, Michelle L.; Kuhn, Olga; Thompson, David; Veillet, Christian

2014-07-01

An overview of instrumentation for the Large Binocular Telescope (LBT) is presented. Optical instrumentation includes the Large Binocular Camera (LBC), a pair of wide-field (24' × 24') mosaic CCD imagers at the prime focus, and the Multi-Object Double Spectrograph (MODS), a pair of dual-beam blue-red optimized long-slit spectrographs mounted at the left and right direct F/15 Gregorian foci incorporating multiple slit masks for multi-object spectroscopy over a 6' field and spectral resolutions of up to 2000. Infrared instrumentation includes the LBT Near-IR Spectrometer (LUCI), a modular near-infrared (0.9-2.5 μm) imager and spectrograph pair mounted at the left and right front-bent F/15 Gregorian foci and designed for seeing-limited (FOV: 4' × 4') imaging, long-slit spectroscopy, and multi-object spectroscopy utilizing cooled slit masks and diffraction limited (FOV: 0'.5 x 0'.5) imaging and long-slit spectroscopy. Strategic instruments under development that can utilize the full 23 m baseline of the LBT include an interferometric cryogenic beam combiner with near-infrared and thermal-infrared instruments for Fizeau imaging and nulling interferometry (LBTI) and an optical bench near- infrared beam combiner utilizing multi-conjugate adaptive optics for high angular resolution and sensitivity (LINC-NIRVANA). LBTI is currently undergoing commissioning and performing science observations on the LBT utilizing the installed adaptive secondary mirrors in both single-sided and two-sided beam combination modes. In addition, a fiber-fed bench spectrograph (PEPSI) capable of ultra high resolution spectroscopy and spectropolarimetry (R = 40,000-300,000) will be available as a principal investigator instrument. Installation and testing of the bench spectrograph will begin in July 2014. Over the past four years the LBC pair, LUCI1, and MODS1 have been commissioned and are now scheduled for routine partner science observations. Both LUCI2 and MODS2 passed their laboratory acceptance milestones in the summer of 2013 and have been installed on the LBT. LUCI2 is currently being commissioned and the data analysis is well underway. Diffraction-limited commissioning of its adaptive optics modes will begin in the 2014B semester. MODS2 commissioning began in May 2014 and will completed in the 2014B semester as well. Binocular testing and commissioning of both the LUCI and MODS pairs will begin in 2014B with the goal that this capability could be offered sometime in 2015. The availability of all these instruments mounted simultaneously on the LBT permits unique science, flexible scheduling, and improved operational support.

Cassini UVIS Observations of Saturn during the Grand Finale Orbits

NASA Astrophysics Data System (ADS)

Pryor, W. R.; Esposito, L. W.; West, R. A.; Jouchoux, A.; Radioti, A.; Grodent, D. C.; Gerard, J. C. M. C.; Gustin, J.; Lamy, L.; Badman, S. V.

2017-12-01

In 2016 and 2017, the Cassini Saturn orbiter executed a final series of high inclination, low-periapsis orbits ideal for studies of Saturn's polar regions. The Cassini Ultraviolet Imaging Spectrograph (UVIS) obtained an extensive set of auroral images, some at the highest spatial resolution obtained during Cassini's long orbital mission (2004-2017). In some cases, two or three spacecraft slews at right angles to the long slit of the spectrograph were required to cover the entire auroral region to form auroral images. We will present selected images from this set showing narrow arcs of emission, more diffuse auroral emissions, multiple auroral arcs in a single image, discrete spots of emission, small scale vortices, large-scale spiral forms, and parallel linear features that appear to cross in places like twisted wires. Some shorter features are transverse to the main auroral arcs, like barbs on a wire. UVIS observations were in some cases simultaneous with auroral observations from the Hubble Space Telescope Space Telescope Imaging Spectrograph (STIS) that will also be presented. UVIS polar images also contain spectral information suitable for studies of the auroral electron energy distribution. The long wavelength part of the UVIS polar images contains a signal from reflected sunlight containing absorption signatures of acetylene and other Saturn hydrocarbons. The hydrocarbon spatial distribution will also be examined.

The optical design of the G-CLEF Spectrograph: the first light instrument for the GMT

NASA Astrophysics Data System (ADS)

Ben-Ami, Sagi; Epps, Harland; Evans, Ian; Mueller, Mark; Podgorski, William; Szentgyorgyi, Andrew

2016-08-01

The GMT-Consortium Large Earth Finder (G-CLEF), the first major light instrument for the GMT, is a fiber-fed, high-resolution echelle spectrograph. In the following paper, we present the optical design of G-CLEF. We emphasize the unique solutions derived for the spectrograph fiber-feed: the Mangin mirror that corrects the cylindrical field curvature, the implementation of VPH grisms as cross dispersers, and our novel solution for a multi-colored exposure meter. We describe the spectrograph blue and red cameras comprised of 7 and 8 elements respectively, with one aspheric surface in each camera, and present the expected echellogram imaged on the instrument focal planes. Finally, we present ghost analysis and mitigation strategy that takes into account both single reflection and double reflection back scattering from various elements in the optical train.

The end-to-end simulator for the E-ELT HIRES high resolution spectrograph

NASA Astrophysics Data System (ADS)

Genoni, M.; Landoni, M.; Riva, M.; Pariani, G.; Mason, E.; Di Marcantonio, P.; Disseau, K.; Di Varano, I.; Gonzalez, O.; Huke, P.; Korhonen, H.; Li Causi, Gianluca

2017-06-01

We present the design, architecture and results of the End-to-End simulator model of the high resolution spectrograph HIRES for the European Extremely Large Telescope (E-ELT). This system can be used as a tool to characterize the spectrograph both by engineers and scientists. The model allows to simulate the behavior of photons starting from the scientific object (modeled bearing in mind the main science drivers) to the detector, considering also calibration light sources, and allowing to perform evaluation of the different parameters of the spectrograph design. In this paper, we will detail the architecture of the simulator and the computational model which are strongly characterized by modularity and flexibility that will be crucial in the next generation astronomical observation projects like E-ELT due to of the high complexity and long-time design and development. Finally, we present synthetic images obtained with the current version of the End-to-End simulator based on the E-ELT HIRES requirements (especially high radial velocity accuracy). Once ingested in the Data reduction Software (DRS), they will allow to verify that the instrument design can achieve the radial velocity accuracy needed by the HIRES science cases.

DARKNESS: A Microwave Kinetic Inductance Detector Integral Field Spectrograph for High-contrast Astronomy

NASA Astrophysics Data System (ADS)

Meeker, Seth R.; Mazin, Benjamin A.; Walter, Alex B.; Strader, Paschal; Fruitwala, Neelay; Bockstiegel, Clint; Szypryt, Paul; Ulbricht, Gerhard; Coiffard, Grégoire; Bumble, Bruce; Cancelo, Gustavo; Zmuda, Ted; Treptow, Ken; Wilcer, Neal; Collura, Giulia; Dodkins, Rupert; Lipartito, Isabel; Zobrist, Nicholas; Bottom, Michael; Shelton, J. Chris; Mawet, Dimitri; van Eyken, Julian C.; Vasisht, Gautam; Serabyn, Eugene

2018-06-01

We present DARKNESS (the DARK-speckle Near-infrared Energy-resolving Superconducting Spectrophotometer), the first of several planned integral field spectrographs to use optical/near-infrared Microwave Kinetic Inductance Detectors (MKIDs) for high-contrast imaging. The photon counting and simultaneous low-resolution spectroscopy provided by MKIDs will enable real-time speckle control techniques and post-processing speckle suppression at frame rates capable of resolving the atmospheric speckles that currently limit high-contrast imaging from the ground. DARKNESS is now operational behind the PALM-3000 extreme adaptive optics system and the Stellar Double Coronagraph at Palomar Observatory. Here, we describe the motivation, design, and characterization of the instrument, early on-sky results, and future prospects.

The CHARIS IFS for high contrast imaging at Subaru

NASA Technical Reports Server (NTRS)

Groff, Tyler D.; Kasdin, N. Jeremy; Limbach, Mary Anne; Galvin, Michael; Carr, Michael A.; Knapp, Gillian; Brandt, Timothy; Loomis, Craig; Jarosik, Norman; Mede, Kyle;

VizieR Online Data Catalog: VI photometry and spectroscopy in h+{chi} Per (Currie+, 2010)

NASA Astrophysics Data System (ADS)

Currie, T.; Hernandez, J.; Irwin, J.; Kenyon, S. J.; Tokarz, S.; Balog, Z.; Bragg, A.; Berlind, P.; Calkins, M.

2010-04-01

Optical VI photometry of h and {chi} Persei were taken with the Mosaic Imager at the 4m Mayall telescope at the Kitt Peak National Observatory on 2006 October 13-16 and 27-30. We acquired low-resolution optical spectroscopy of Two Micron All Sky Survey (2MASS)-detected stars within 1deg2 of the cluster centers. For faint stars, we used the multiobject, fiber-fed spectrograph Hectospec on the 6.5m MMT. Brighter stars were observed with the fiber-fed spectrograph Hydra on the 3.5m WIYN telescope at Kitt Peak National Observatory and single-slit FAST spectrograph on the 1.5m Tillinghast telescope at the Fred Lawrence Whipple Observatory. (4 data files).

Optical Technologies for UV Remote Sensing Instruments

NASA Technical Reports Server (NTRS)

Keski-Kuha, R. A. M.; Osantowski, J. F.; Leviton, D. B.; Saha, T. T.; Content, D. A.; Boucarut, R. A.; Gum, J. S.; Wright, G. A.; Fleetwood, C. M.; Madison, T. J.

1993-01-01

Over the last decade significant advances in technology have made possible development of instruments with substantially improved efficiency in the UV spectral region. In the area of optical coatings and materials, the importance of recent developments in chemical vapor deposited (CVD) silicon carbide (SiC) mirrors, SiC films, and multilayer coatings in the context of ultraviolet instrumentation design are discussed. For example, the development of chemically vapor deposited (CVD) silicon carbide (SiC) mirrors, with high ultraviolet (UV) reflectance and low scatter surfaces, provides the opportunity to extend higher spectral/spatial resolution capability into the 50-nm region. Optical coatings for normal incidence diffraction gratings are particularly important for the evolution of efficient extreme ultraviolet (EUV) spectrographs. SiC films are important for optimizing the spectrograph performance in the 90 nm spectral region. The performance evaluation of the flight optical components for the Solar Ultraviolet Measurements of Emitted Radiation (SUMER) instrument, a spectroscopic instrument to fly aboard the Solar and Heliospheric Observatory (SOHO) mission, designed to study dynamic processes, temperatures, and densities in the plasma of the upper atmosphere of the Sun in the wavelength range from 50 nm to 160 nm, is discussed. The optical components were evaluated for imaging and scatter in the UV. The performance evaluation of SOHO/CDS (Coronal Diagnostic Spectrometer) flight gratings tested for spectral resolution and scatter in the DGEF is reviewed and preliminary results on resolution and scatter testing of Space Telescope Imaging Spectrograph (STIS) technology development diffraction gratings are presented.

NRA: First Multiwavelength, Multiple Layer Doppler Imaging of an Active Binary

NASA Technical Reports Server (NTRS)

Dempsey, Robert C.

1998-01-01

In this final report, grantee reports on data obtained from 26 orbits of continuous observing time with the Hubble Space Telescope's Goddard High Resolution Spectrograph in order to produce a comprehensive 2-D image of the RSCVn V824 Ara at MgII, CIV and for the first time ever, the coronal diagnostic line of FeXXI 1356A.

Optical and Infrared Spectral Features of Nova Canis Majoris 2018

NASA Astrophysics Data System (ADS)

Rudy, Richard; Mauerhan, Jon; Crawford, Kirk; Russell, Ray; Wiktorowicz, Sloane

2018-04-01

Optical and IR spectra from 0.47-2.5 microns (resolution: 5-30 angstroms) of Nova Canis Majoris (CBET 4499), were obtained 2018 April 21.14 (UT) with the Aerospace Corporation's 1.0 m telescope using its Visible and Infrared Imaging Spectrograph (VNIRIS).

Ultraviolet Views of Enceladus, Tethys, and Dione

NASA Technical Reports Server (NTRS)

Hansen, C. J.; Hendrix, A. R.

2005-01-01

The Cassini Ultraviolet Imaging Spectrograph (UVIS) has collected ultraviolet observations of many of Saturn's icy moons since Cassini's insertion into orbit around Saturn. We will report on results from Enceladus, Tethys and Dione, orbiting in the Saturn system at distances of 3.95, 4.88 and 6.26 Saturn radii, respectively. Icy satellite science objectives of the UVIS include investigations of surface age and evolution, surface composition and chemistry, and tenuous exospheres. We address these objectives by producing albedo maps, and reflection and emission spectra, and observing stellar occultations. UVIS has four channels: EUV: Extreme Ultraviolet (55 nm to 110 nm), FUV: Far Ultraviolet (110 to 190 nm), HSP: High Speed Photometer, and HDAC: Hydrogen-Deuterium Absorption Cell. The EUV and FUV spectrographs image onto a 2-dimensional detector, with 64 spatial rows by 1024 spectral columns. To-date we have focused primarily on the far ultraviolet data acquired with the low resolution slit width (4.8 angstrom spectral resolution). Additional information is included in the original extended abstract.

Data reductions and data quality for the high resolution spectrograph on the Southern African Large Telescope

NASA Astrophysics Data System (ADS)

Crawford, S. M.; Crause, Lisa; Depagne, Éric; Ilkiewicz, Krystian; Schroeder, Anja; Kuhn, Rudolph; Hettlage, Christian; Romero Colmenaro, Encarni; Kniazev, Alexei; Väisänen, Petri

2016-08-01

The High Resolution Spectrograph (HRS) on the Southern African Large Telescope (SALT) is a dual beam, fiber-fed echelle spectrograph providing high resolution capabilities to the SALT observing community. We describe the available data reduction tools and the procedures put in place for regular monitoring of the data quality from the spectrograph. Data reductions are carried out through the pyhrs package. The data characteristics and instrument stability are reported as part of the SALT Dashboard to help monitor the performance of the instrument.

The PALM-3000 high-order adaptive optics system for Palomar Observatory

NASA Astrophysics Data System (ADS)

Bouchez, Antonin H.; Dekany, Richard G.; Angione, John R.; Baranec, Christoph; Britton, Matthew C.; Bui, Khanh; Burruss, Rick S.; Cromer, John L.; Guiwits, Stephen R.; Henning, John R.; Hickey, Jeff; McKenna, Daniel L.; Moore, Anna M.; Roberts, Jennifer E.; Trinh, Thang Q.; Troy, Mitchell; Truong, Tuan N.; Velur, Viswa

2008-07-01

Deployed as a multi-user shared facility on the 5.1 meter Hale Telescope at Palomar Observatory, the PALM-3000 highorder upgrade to the successful Palomar Adaptive Optics System will deliver extreme AO correction in the near-infrared, and diffraction-limited images down to visible wavelengths, using both natural and sodium laser guide stars. Wavefront control will be provided by two deformable mirrors, a 3368 active actuator woofer and 349 active actuator tweeter, controlled at up to 3 kHz using an innovative wavefront processor based on a cluster of 17 graphics processing units. A Shack-Hartmann wavefront sensor with selectable pupil sampling will provide high-order wavefront sensing, while an infrared tip/tilt sensor and visible truth wavefront sensor will provide low-order LGS control. Four back-end instruments are planned at first light: the PHARO near-infrared camera/spectrograph, the SWIFT visible light integral field spectrograph, Project 1640, a near-infrared coronagraphic integral field spectrograph, and 888Cam, a high-resolution visible light imager.

VizieR Online Data Catalog: Palomar Transient Factory SNe IIn photometry (Ofek+, 2014)

NASA Astrophysics Data System (ADS)

Ofek, E. O.; Arcavi, I.; Tal, D.; Sullivan, M.; Gal-Yam, A.; Kulkarni, S. R.; Nugent, P. E.; Ben-Ami, S.; Bersier, D.; Cao, Y.; Cenko, S. B.; De Cia, A.; Filippenko, A. V.; Fransson, C.; Kasliwal, M. M.; Laher, R.; Surace, J.; Quimby, R.; Yaron, O.

2017-07-01

The Palomar Transient Factory (PTF; Law et al. 2009PASP..121.1395L; Rau et al. 2009PASP..121.1334R) and its extension the intermediate PTF (iPTF) found over 2200 spectroscopically confirmed SNe. We selected 19 SNe IIn for which PTF/iPTF has good coverage of the light-curve rise and peak; they are listed in Table 1. Optical spectra were obtained with a variety of telescopes and instruments, including the Double Spectrograph (Oke & Gunn 1982PASP...94..586O) at the Palomar 5 m Hale telescope, the Kast spectrograph (Miller & Stone 1993, Lick Observatory Technical Report 66 (Santa Cruz, CA: Lick Observatory)) at the Lick 3 m Shane telescope, the Low Resolution Imaging Spectrometer (Oke et al. 1995PASP..107..375O) on the Keck-1 10 m telescope, and the Deep Extragalactic Imaging Multi-Object Spectrograph (Faber et al. 2003SPIE.4841.1657F) on the Keck-2 10 m telescope. (2 data files).

Slitless Solar Spectroscopy

NASA Technical Reports Server (NTRS)

Davila, Joseph M.; Jones, Sahela

2011-01-01

Spectrographs have traditionally suffered from the inability to obtain line intensities, widths, and Doppler shifts over large spatial regions of the Sun quickly because of the narrow instantaneous field of view. This has limited the spectroscopic analysis of rapidly varying solar features like, flares, CME eruptions, coronal jets, and reconnection regions. Imagers have provided high time resolution images of the full Sun with limited spectral resolution. In this paper we present recent advances in deconvolving spectrally dispersed images obtained through broad slits. We use this new theoretical formulation to examine the effectiveness of various potential observing scenarios, spatial and spectral resolutions, signal to noise ratio, and other instrument characteristics. This information will lay the foundation for a new generation of spectral imagers optimized for slitless spectral operation, while retaining the ability to obtain spectral information in transient solar events.

A solar extreme ultraviolet telescope and spectrograph for space shuttle. Volume 1: Investigation and technical plan

NASA Technical Reports Server (NTRS)

Neupert, W. M.

1978-01-01

A scientific investigation of heating and mass transport in the solar corona that is currently planned for a future Shuttle/Spacelab flight is outlined. The instrument to be used is a near-normal incidence grating spectrograph fed by a grazing incidence Wolter Type 2 telescope. A toroidal grating design provides stigmatic images of the corona up to 8 arc min in extent over the spectral region from 225 A to 370 A. Spatial resolution of at least 2 arc sec and spectral resolution of 0.050 A is achievable throughout the central 4 arc min field or view. Primary scientific data are recorded on Schumann-type film. An H-alpha slit jaw monitor and zero order extreme ultraviolet monitor are also planned to support instrument operation.

VizieR Online Data Catalog: Chemical analysis of CH stars. II. (Karinkuzhi+, 2015)

NASA Astrophysics Data System (ADS)

Karinkuzhi, D.; Goswami, A.

2017-10-01

Low-resolution spectra of these objects obtained from 2m Himalayan Chandra Telescope at the Indian Astronomical Observatory, Hanle using HFOSC clearly show strong features due to carbon. HFOSC is an optical imager cum spectrograph for conducting low- and medium-resolution grism spectroscopy (http://www.iiap.res.in/iao/hfosc.html). High-resolution spectra necessary for abundance analyses of the programme stars are taken from the ELODIE archive (Moultaka et al. 2004PASP..116..693M). (7 data files).

Conceptual design for an AIUC multi-purpose spectrograph camera using DMD technology

NASA Astrophysics Data System (ADS)

Rukdee, S.; Bauer, F.; Drass, H.; Vanzi, L.; Jordan, A.; Barrientos, F.

2017-02-01

Current and upcoming massive astronomical surveys are expected to discover a torrent of objects, which need groundbased follow-up observations to characterize their nature. For transient objects in particular, rapid early and efficient spectroscopic identification is needed. In particular, a small-field Integral Field Unit (IFU) would mitigate traditional slit losses and acquisition time. To this end, we present the design of a Digital Micromirror Device (DMD) multi-purpose spectrograph camera capable of running in several modes: traditional longslit, small-field patrol IFU, multi-object and full-field IFU mode via Hadamard spectra reconstruction. AIUC Optical multi-purpose CAMera (AIUCOCAM) is a low-resolution spectrograph camera of R 1,600 covering the spectral range of 0.45-0.85 μm. We employ a VPH grating as a disperser, which is removable to allow an imaging mode. This spectrograph is envisioned for use on a 1-2 m class telescope in Chile to take advantage of good site conditions. We present design decisions and challenges for a costeffective robotized spectrograph. The resulting instrument is remarkably versatile, capable of addressing a wide range of scientific topics.

The instrument development status of hyper-spectral imager suite (HISUI)

NASA Astrophysics Data System (ADS)

Itoh, Yoshiyuki; Kawashima, Takahiro; Inada, Hitomi; Tanii, Jun; Iwasaki, Akira

2012-11-01

The hyper-multi spectral mission named HISUI (Hyper-spectral Imager SUIte) is the next Japanese earth observation project. This project is the follow up mission of the Advanced Spaceborne Thermal Emission and reflection Radiometer (ASTER) and Advanced Land Imager (ALDS). HISUI is composed of hyperspectral radiometer with higher spectral resolution and multi-spectral radiometer with higher spatial resolution. The development of functional evaluation model was carried out to confirm the spectral and radiometric performance prior to the flight model manufacture phase. This model contains the VNIR and SWIR spectrograph, the VNIR and SWIR detector assemblies with a mechanical cooler for SWIR, signal processing circuit and on-board calibration source.

Waveguide image-slicers for ultrahigh resolution spectroscopy

NASA Astrophysics Data System (ADS)

Beckert, Erik; Strassmeier, Klaus G.; Woche, Manfred; Eberhardt, Ramona; Tünnermann, Andreas; Andersen, Michael

2008-07-01

Waveguide image-slicer prototypes with resolutions up to 310.000 for the fiber fed PEPSI echelle spectrograph at the LBT and single waveguide thicknesses of down to 30 μm have been manufactured. The waveguides were macroscopically prepared, stacked up to an order of 7 and thinned back to square stack cross sections. A high filling ratio was achieved by realizing homogenous adhesive gaps of 4.6 μm, using index matching adhesives for TIR within the waveguides. The image-slicer stacks can be used in immersion mode and are miniaturized to be implemented in a set of four, measurements indicate an overall efficiency of above 80% for them.

The Large Ultraviolet/Optical/Infrared Surveyor (LUVOIR)

NASA Astrophysics Data System (ADS)

Peterson, Bradley M.; Fischer, Debra; LUVOIR Science and Technology Definition Team

2017-01-01

LUVOIR is one of four potential large mission concepts for which the NASA Astrophysics Division has commissioned studies by Science and Technology Definition Teams (STDTs) drawn from the astronomical community. LUVOIR will have an 8 to16-m segmented primary mirror and operate at the Sun-Earth L2 point. It will be designed to support a broad range of astrophysics and exoplanet studies. The notional initial complement of instruments will include 1) a high-performance optical/NIR coronagraph with imaging and spectroscopic capability, 2) a UV imager and spectrograph with high spectral resolution and multi-object capability, 3) a high-definition wide-field optical/NIR camera, and 4) a multi-resolution optical/NIR spectrograph. LUVOIR will be designed for extreme stability to support unprecedented spatial resolution and coronagraphy. It is intended to be a long-lifetime facility that is both serviceable and upgradable. This is the first report by the LUVOIR STDT to the community on the top-level architectures we are studying, including preliminary capabilities of a mission with those parameters. The STDT seeks feedback from the astronomical community for key science investigations that can be undertaken with the notional instrument suite and to identify desirable capabilities that will enable additional key science.

Hollow-cathode lamps as optical frequency standards: the influence of optical imaging on the line-strength ratios

NASA Astrophysics Data System (ADS)

Huke, Philipp; Tal-Or, Lev; Sarmiento, Luis Fernando; Reiners, Ansgar

2016-07-01

Hollow cathode discharge lamps (HCLs) have been successfully used in recent years as calibration sources of optical astronomical spectrographs. The numerous narrow metal lines have stable wavelengths, which makes them well suited for m/s calibration accuracy of high-resolution spectrographs, while the buffer-gas lines are less stable and less useful. Accordingly, an important property is the metal-to-gas line-strength ratio (Rmetal/gas). Processes inside the lamp cause the light to be emitted from different regions between the cathode and the anode leaing to the emission of different beams with different values of Rmetal/gas. We used commercially- available HCLs to measure and characterize these beams with respect to their spatial distribution, their angle of propagation relative to the optical axis, and their values of Rmetal/gas. We conclude that a good imaging of an HCL into a fiber-fed spectrograph would consist of an aperture close to its front window in order to filter out the parts of the beam with low Rmetal/gas, and of a lens to collimate the important central beam. We show that Rmetal/gas can be further improved with only minor adjustments of the imaging parameters, and that the imaging scheme that yields the highest Rmetal/gas does not necessarily provide the highest flux.

Ionospheric Observations During a Geomagnetic Storm from LITES on the ISS

NASA Astrophysics Data System (ADS)

Finn, S. C.; Stephan, A. W.; Cook, T.; Budzien, S. A.; Chakrabarti, S.; Erickson, P. J.; Geddes, G.

2017-12-01

The Limb-Imaging Ionospheric and Thermospheric Extreme-Ultraviolet Spectrograph (LITES) is an extreme-ultraviolet imaging spectrograph that launched in February 2017 and was installed on the International Space Station (ISS). LITES is limb-viewing ( 150 - 350 km tangent altitude) and measures airglow emissions from 60 - 140 nm with 0.2° angular and 1 nm spectral resolutions. We present early LITES results of observations during a G2 geomagnetic storm in April 2017. In addition to LITES data, we will show complementary ground-based incoherent scatter radar (ISR) observations from Millstone Hill during this storm. The combination of LITES EUV space-based observations with the ground-based radio data is an example of the capability of campaign-style measurements of the ionosphere-thermosphere system using multiwavelength ground- and space-based instruments.

Fast Imaging Solar Spectrograph System in New Solar Telescope

NASA Astrophysics Data System (ADS)

Park, Y.-D.; Kim, Y. H.; Chae, J.; Goode, P. R.; Cho, K. S.; Park, H. M.; Nah, J. K.; Jang, B. H.

2010-12-01

In 2004, Big Bear Solar Observatory in California, USA launched a project for construction of the world's largest aperture solar telescope (D = 1.6m) called New Solar Telescope(NST). University of Hawaii (UH) and Korea Astronomy and Space Science Institute(KASI) partly collaborate on the project. NST is a designed off-axis parabolic Gregorian reflector with very high spatial resolution(0.07 arcsec at 5000A) and is equipped with several scientific instruments such as Visible Imaging Magnetograph (VIM), InfraRed Imaging Magnetograph IRIM), and so on. Since these scientific instruments are focused on studies of the solar photosphere, we need a post-focus instrument for the NST to study the fine structures and dynamic patterns of the solar chromosphere and low Transition Region (TR) layer, including filaments/prominences, spicules, jets, micro flares, etc. For this reason, we developed and installed a fast imaging solar spectrograph(FISS) system on the NST withadvantages of achieving compact design with high spectral resolution and small aberration as well as recording many solar spectral lines in a single and/or dual band mode. FISS was installed in May, 2010 and now we carry out a test observation. In this talk, we introduce the FISS system and the results of the test observation after FISS installation.

Capabilities, performance, and status of the SOFIA science instrument suite

NASA Astrophysics Data System (ADS)

Miles, John W.; Helton, L. Andrew; Sankrit, Ravi; Andersson, B. G.; Becklin, E. E.; De Buizer, James M.; Dowell, C. D.; Dunham, Edward W.; Güsten, Rolf; Harper, Doyal A.; Herter, Terry L.; Keller, Luke D.; Klein, Randolf; Krabbe, Alfred; Marcum, Pamela M.; McLean, Ian S.; Reach, William T.; Richter, Matthew J.; Roellig, Thomas L.; Sandell, Göran; Savage, Maureen L.; Smith, Erin C.; Temi, Pasquale; Vacca, William D.; Vaillancourt, John E.; Van Cleve, Jeffery E.; Young, Erick T.; Zell, Peter T.

2013-09-01

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is an airborne observatory, carrying a 2.5 m telescope onboard a heavily modified Boeing 747SP aircraft. SOFIA is optimized for operation at infrared wavelengths, much of which is obscured for ground-based observatories by atmospheric water vapor. The SOFIA science instrument complement consists of seven instruments: FORCAST (Faint Object InfraRed CAmera for the SOFIA Telescope), GREAT (German Receiver for Astronomy at Terahertz Frequencies), HIPO (High-speed Imaging Photometer for Occultations), FLITECAM (First Light Infrared Test Experiment CAMera), FIFI-LS (Far-Infrared Field-Imaging Line Spectrometer), EXES (Echelon-Cross-Echelle Spectrograph), and HAWC (High-resolution Airborne Wideband Camera). FORCAST is a 5-40 μm imager with grism spectroscopy, developed at Cornell University. GREAT is a heterodyne spectrometer providing high-resolution spectroscopy in several bands from 60-240 μm, developed at the Max Planck Institute for Radio Astronomy. HIPO is a 0.3-1.1 μm imager, developed at Lowell Observatory. FLITECAM is a 1-5 μm wide-field imager with grism spectroscopy, developed at UCLA. FIFI-LS is a 42-210 μm integral field imaging grating spectrometer, developed at the University of Stuttgart. EXES is a 5-28 μm high-resolution spectrograph, developed at UC Davis and NASA ARC. HAWC is a 50-240 μm imager, developed at the University of Chicago, and undergoing an upgrade at JPL to add polarimetry capability and substantially larger GSFC detectors. We describe the capabilities, performance, and status of each instrument, highlighting science results obtained using FORCAST, GREAT, and HIPO during SOFIA Early Science observations conducted in 2011.

The SLICE, CHESS, and SISTINE Ultraviolet Spectrographs: Rocket-Borne Instrumentation Supporting Future Astrophysics Missions

NASA Astrophysics Data System (ADS)

France, Kevin; Hoadley, Keri; Fleming, Brian T.; Kane, Robert; Nell, Nicholas; Beasley, Matthew; Green, James C.

2016-03-01

NASA’s suborbital program provides an opportunity to conduct unique science experiments above Earth’s atmosphere and is a pipeline for the technology and personnel essential to future space astrophysics, heliophysics, and atmospheric science missions. In this paper, we describe three astronomy payloads developed (or in development) by the Ultraviolet Rocket Group at the University of Colorado. These far-ultraviolet (UV) (100-160nm) spectrographic instruments are used to study a range of scientific topics, from gas in the interstellar medium (accessing diagnostics of material spanning five orders of magnitude in temperature in a single observation) to the energetic radiation environment of nearby exoplanetary systems. The three instruments, Suborbital Local Interstellar Cloud Experiment (SLICE), Colorado High-resolution Echelle Stellar Spectrograph (CHESS), and Suborbital Imaging Spectrograph for Transition region Irradiance from Nearby Exoplanet host stars (SISTINE) form a progression of instrument designs and component-level technology maturation. SLICE is a pathfinder instrument for the development of new data handling, storage, and telemetry techniques. CHESS and SISTINE are testbeds for technology and instrument design enabling high-resolution (R>105) point source spectroscopy and high throughput imaging spectroscopy, respectively, in support of future Explorer, Probe, and Flagship-class missions. The CHESS and SISTINE payloads support the development and flight testing of large-format photon-counting detectors and advanced optical coatings: NASA’s top two technology priorities for enabling a future flagship observatory (e.g. the LUVOIR Surveyor concept) that offers factors of ˜50-100 gain in UV spectroscopy capability over the Hubble Space Telescope. We present the design, component level laboratory characterization, and flight results for these instruments.

First-generation instrumentation for the Discovery Channel Telescope

NASA Astrophysics Data System (ADS)

Bida, Thomas A.; Dunham, Edward W.; Massey, Philip; Roe, Henry G.

2014-07-01

The 4.3m Discovery Channel Telescope (DCT) has been conducting part-time science operations since January 2013. The f/6.1, 0.5° field-of-view at the RC focus is accessible through the Cassegrain instrument cube assembly, which can support 5 co-mounted instruments with rapid feed selection via deployable fold mirrors. Lowell Observatory has developed the Large Monolithic Imager (LMI), a 12.3' FOV 6K x 6K single CCD camera with a dual filter wheel, and installed at the straight-through, field-corrected RC focal station, which has served as the primary early science DCT instrument. Two low-resolution facility spectrographs are currently under development with first light for each anticipated by early 2015: the upgraded DeVeny Spectrograph, to be utilized for single object optical spectroscopy, and the unique Near-Infrared High-Throughput Spectrograph (NIHTS), optimized for single-shot JHK spectroscopy of faint solar system objects. These spectrographs will be mounted at folded RC ports, and the NIHTS installation will feature simultaneous optical imaging with LMI through use of a dichroic fold mirror. We report on the design, construction, commissioning, and progress of these 3 instruments in detail. We also discuss plans for installation of additional facility instrumentation on the DCT.

UVSTAR: An imaging spectrograph with telescope for the Shuttle Hitchhiker-M platform

NASA Technical Reports Server (NTRS)

Stalio, Roberto; Sandel, Bill R.; Broadfoot, A. Lyle

1993-01-01

UVSTAR is an EUV spectral imager intended as a facility instrument devoted to solar system and astronomy studies. It covers the wavelength range of 500 to 1250 A, with sufficient spectral resolution to separate emission lines and to form spectrally resolved images of extended plasma sources. Targets include the Io plasma torus at Jupiter, hot stars, planetary nebulae and bright galaxies. UVSTAR consists of a pair of telescopes and concave grating spectrographs that cover the overlapping spectral ranges of 500-900 and 850-1250 A. The telescopes use two 30 cm diameter off-axis paraboloids having focal length of 1.5 m. An image of the target is formed at the entrance slits of the two concave grating spectrographs. The gratings provide dispersion and re-image the slits at the detectors, intensified CCD's. The readout format of the detectors can be chosen by computer, and three slit widths are selectable to adapt the instrument to specific tasks. UVSTAR has internal gimbals which allow rotation of plus or minus 3 deg about each of two axes. Dedicated finding and tracking telescopes will acquire and track the target after rough pointing is achieved by orienting the Orbiter. Responsibilities for implementation and utilization of UVSTAR are shared by groups in Italy and the U.S. UVSTAR is scheduled for flight in early 1995, timed for an opportunity to observe the Jovian system.

The Large UV/Optical/Infrared Surveyor (LUVOIR): Decadal Mission concept design update

NASA Astrophysics Data System (ADS)

Bolcar, Matthew R.; Aloezos, Steve; Bly, Vincent T.; Collins, Christine; Crooke, Julie; Dressing, Courtney D.; Fantano, Lou; Feinberg, Lee D.; France, Kevin; Gochar, Gene; Gong, Qian; Hylan, Jason E.; Jones, Andrew; Linares, Irving; Postman, Marc; Pueyo, Laurent; Roberge, Aki; Sacks, Lia; Tompkins, Steven; West, Garrett

2017-09-01

In preparation for the 2020 Astrophysics Decadal Survey, NASA has commissioned the study of four large mission concepts, including the Large Ultraviolet / Optical / Infrared (LUVOIR) Surveyor. The LUVOIR Science and Technology Definition Team (STDT) has identified a broad range of science objectives including the direct imaging and spectral characterization of habitable exoplanets around sun-like stars, the study of galaxy formation and evolution, the epoch of reionization, star and planet formation, and the remote sensing of Solar System bodies. NASA's Goddard Space Flight Center (GSFC) is providing the design and engineering support to develop executable and feasible mission concepts that are capable of the identified science objectives. We present an update on the first of two architectures being studied: a 15- meter-diameter segmented-aperture telescope with a suite of serviceable instruments operating over a range of wavelengths between 100 nm to 2.5 μm. Four instruments are being developed for this architecture: an optical / near-infrared coronagraph capable of 10-10 contrast at inner working angles as small as 2 λ/D the LUVOIR UV Multi-object Spectrograph (LUMOS), which will provide low- and medium-resolution UV (100 - 400 nm) multi-object imaging spectroscopy in addition to far-UV imaging; the High Definition Imager (HDI), a high-resolution wide-field-of-view NUV-Optical-IR imager; and a UV spectro-polarimeter being contributed by Centre National d'Etudes Spatiales (CNES). A fifth instrument, a multi-resolution optical-NIR spectrograph, is planned as part of a second architecture to be studied in late 2017.

Optical design of the PEPSI high-resolution spectrograph at LBT

NASA Astrophysics Data System (ADS)

Andersen, Michael I.; Spano, Paolo; Woche, Manfred; Strassmeier, Klaus G.; Beckert, Erik

2004-09-01

PEPSI is a high-resolution, fiber fed echelle spectrograph with polarimetric capabilities for the LBT. In order to reach a maximum resolution R=120.000 in polarimetric mode and 300.000 in integral light mode with high efficiency in the spectral range 390-1050~nm, we designed a white-pupil configuration with Maksutov collimators. Light is dispersed by an R4 31.6 lines/mm monolithic echelle grating mosaic and split into two arms through dichroics. The two arms, optimized for the spectral range 390-550~nm and 550-1050~nm, respectively, consist of Maksutov transfer collimators, VPH-grism cross dispersers, optimized dioptric cameras and 7.5K x 7.5K 8~μ CCDs. Fibers of different core sizes coupled to different image-slicers allow a high throughput, comparable to that of direct feed instruments. The optical configuration with only spherical and cylindrical surfaces, except for one aspherical surface in each camera, reduces costs and guarantees high optical quality. PEPSI is under construction at AIP with first light expected in 2006.

MuSICa image slicer prototype at 1.5-m GREGOR solar telescope

NASA Astrophysics Data System (ADS)

Calcines, A.; López, R. L.; Collados, M.; Vega Reyes, N.

2014-07-01

Integral Field Spectroscopy is an innovative technique that is being implemented in the state-of-the-art instruments of the largest night-time telescopes, however, it is still a novelty for solar instrumentation. A new concept of image slicer, called MuSICa (Multi-Slit Image slicer based on collimator-Camera), has been designed for the integral field spectrograph of the 4-m European Solar Telescope. This communication presents an image slicer prototype of MuSICa for GRIS, the spectrograph of the 1.5-m GREGOR solar telescope located at the Observatory of El Teide. MuSICa at GRIS reorganizes a 2-D field of view of 24.5 arcsec into a slit of 0.367 arcsec width by 66.76 arcsec length distributed horizontally. It will operate together with the TIP-II polarimeter to offer high resolution integral field spectropolarimetry. It will also have a bidimensional field of view scanning system to cover a field of view up to 1 by 1 arcmin.

Studying the inner regions of young stars and their disks with aperture masking interferometry

NASA Astrophysics Data System (ADS)

Greenbaum, Alexandra; Sivaramakrishnan, Anand; GPI Instrument Team; NIRISS Instrument Team

2017-01-01

High resolution aperture masking interferometry complements coronagraphic imagers to provide a unique perspective on star and planet formation at more moderate contrast. By targeting young stars, especially those with disks, we aim to understand complex protoplanetary environments. Ground-based non-redundant masking (NRM) paired with spectrographs and polarimeters probes both thermally emitting young companions, possibly embedded in the disk or gap and scattered light in protoplanetary disks. And soon the community will have access to the most stable NRM conditions yet, with the Near Infrared Imager and Slitless Spectrograph (NIRISS) Aperture Masking Interferometry (AMI) mode on the James Webb Space Telescope. I will present my thesis work commissioning the Gemini Planet Imager’s NRM, highlighting results through both its spectroscopy and polarimetry modes, which set the stage for future space-based imaging. I will also give an overview of NIRISS-AMI capabilities and performance predictions for imaging young low-mass companions and disks, and how it will complement other instruments on JWST.

VizieR Online Data Catalog: R-band light curves of type II supernovae (Rubin+, 2016)

NASA Astrophysics Data System (ADS)

Rubin, A.; Gal-Yam, A.; De Cia, A.; Horesh, A.; Khazov, D.; Ofek, E. O.; Kulkarni, S. R.; Arcavi, I.; Manulis, I.; Yaron, O.; Vreeswijk, P.; Kasliwal, M. M.; Ben-Ami, S.; Perley, D. A.; Cao, Y.; Cenko, S. B.; Rebbapragada, U. D.; Wozniak, P. R.; Filippenko, A. V.; Clubb, K. I.; Nugent, P. E.; Pan, Y.-C.; Badenes, C.; Howell, D. A.; Valenti, S.; Sand, D.; Sollerman, J.; Johansson, J.; Leonard, D. C.; Horst, J. C.; Armen, S. F.; Fedrow, J. M.; Quimby, R. M.; Mazzali, P.; Pian, E.; Sternberg, A.; Matheson, T.; Sullivan, M.; Maguire, K.; Lazarevic, S.

2016-05-01

Our sample consists of 57 SNe from the PTF (Law et al. 2009PASP..121.1395L; Rau et al. 2009PASP..121.1334R) and the intermediate Palomar Transient Factory (iPTF; Kulkarni 2013ATel.4807....1K) surveys. Data were routinely collected by the Palomar 48-inch survey telescope in the Mould R-band. Follow-up observations were conducted mainly with the robotic 60-inch telescope using an SDSS r-band filter, with additional telescopes providing supplementary photometry and spectroscopy (see Gal-Yam et al. 2011, J/ApJ/736/159). The full list of SNe, their coordinates, and classification spectra are presented in Table 1. Most of the spectra were obtained with the Double Spectrograph on the 5m Hale telescope at Palomar Observatory, the Kast spectrograph on the Shane 3m telescope at Lick Observatory, the Low Resolution Imaging Spectrometer (LRIS) on the Keck I 10m telescope, and the DEep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck II 10m telescope. (2 data files).

Spectroscopic Classification of PSN J11492548-0507138 as a Type Ia Supernova

NASA Astrophysics Data System (ADS)

Rudy, R. J.; Ardila, D. R.; Crawford, K. B.; Moody, M. S. L.; Safrit, T. K.; Puetter, R. C.

2015-07-01

Optical and IR spectra from 0.47-2.5 microns (resolution: 5-30 angstroms) of PSN J11492548-0507138 (ATEL #7732) were obtained on 2015 July 12.15 with the Shane 3.0 m Telescope of Lick Observatory using the Aerospace Corporation's Visible and Infrared Imaging Spectrograph (VNIRIS).

Spatial imaging in the soft x-ray region (20--304 A) utilizing the astigmatism of a grazing incidence concave grating

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

Nudelfuden, A.; Solanki, R.; Moos, H.W.

1985-03-15

Soft x-ray (20--304--A) astigmatic line shapes were measured in order to evaluate the spatial imaging properties of a Rowland mounted concave grating in grazing incidence. The practicability of coarse 1-D spatial imaging in the soft x-ray region is demonstrated. Spatial resolution equivalent to approx.4 cm at a source distance of 2 m can be achieved with practical parameters (e.g., sensitivity and time resolution) for a fusion diagnostic spectrograph. The results are compared to computer-generated ray tracings and found to be in good agreement. The ray tracing program which models the grazing incidence optics is discussed.

Multi-resolution waveguide image slicer for the PEPSI instrument

NASA Astrophysics Data System (ADS)

Beckert, Erik; Strassmeier, Klaus G.; Woche, Manfred; Harnisch, Gerd; Hornaff, Marcel; Weber, Michael; Barnes, Stuart

2016-07-01

A waveguide image slicer with resolutions up to 270.000 (planned: 300.000) for the fiber fed PEPSI echelle spectrograph at the LBT and single waveguide thicknesses of down to 70 μm has been manufactured and tested. The waveguides were macroscopically prepared, stacked up to an order of seven and thinned back to square stack cross sections. A high filling ratio was achieved by realizing homogenous adhesive gaps of 3.6 μm, using index matching adhesives for TIR within the waveguides. The image slicer stacks are used in immersion mode and are miniaturized to enable implementation in a set of 2x8. The overall efficiency is between 92 % and 96 %.

bHROS: A New High-Resolution Spectrograph Available on Gemini South

NASA Astrophysics Data System (ADS)

Margheim, S. J.; Gemini bHROS Team

2005-12-01

The Gemini bench-mounted High-Resolution Spectrograph (bHROS) is available for science programs beginning in 2006A. bHROS is the highest resolution (R=150,000) optical echelle spectrograph optimized for use on an 8-meter telescope. bHROS is fiber-fed via GMOS-S from the Gemini South focal plane and is available in both a dual-fiber Object/Sky mode and a single (larger) Object-only mode. Instrument characteristics and sample data taken during commissioning will be presented.

The IFS for WFIRST CGI: Science Requirements to Design

NASA Astrophysics Data System (ADS)

Groff, Tyler; Gong, Qian; Mandell, Avi M.; Zimmerman, Neil; Rizzo, Maxime; McElwain, Michael; harvey, david; Saxena, Prabal; cady, eric; mejia prada, camilo

2018-01-01

Direct Imaging of exoplanets using a coronagraph has become a major field of research both on the ground and in space. Key to the science of direct imaging is the spectroscopic capabilities of the instrument, our ability to extract spectra, and measure the abundance of molecular species such as Methane. To take these spectra, the WFIRST coronagraph instrument (CGI) uses an integral field spectrograph (IFS), which encodes the spectrum into a two-dimensional image on the detector. This results in more efficient detection and characterization of targets, and the spectral information is critical to achieving detection limits below the speckle floor of the imager. The CGI IFS operates in three 18% bands spanning 600nm to 970nm at a nominal spectral resolution of R50. We present the current science and engineering requirements for the IFS design, the instrument design, anticipated performance, and how the calibration is integrated into the focal plane wavefront control algorithms. We also highlight the role of the Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) at the JPL High Contrast Imaging Testbed to demonstrate performance and validate calibration methodologies for the flight instrument.

LRS2: A New Integral Field Spectrograph for the HET

NASA Astrophysics Data System (ADS)

Tuttle, Sarah E.; Hill, Gary J.; Chonis, Taylor S.; Tonnesen, Stephanie

2016-01-01

Here we present LRS2 (Low Resolution Spectrograph) and highlight early science opportunities with the newly upgraded Hobby Eberly telescope (HET). LRS2 is a four-channel optical wavelength (370nm - 1micron) spectrograph based on two VIRUS unit spectrographs. This fiber-fed integral field spectrograph covers a 12" x 6" field of view, switched between the two units (one blue, and one red) at R~2000. We highlight design elements, including the fundamental modification to grisms (from VPH gratings in VIRUS) to access the higher resolution. We discuss early science opportunities, including investigating nearby "blue-bulge" spiral galaxies and their anomalous star formation distribution.

STS-82 Discovery payloads being integrated in VPF

NASA Image and Video Library

1997-01-30

KENNEDY SPACE CENTER, FLORIDA STS-82 PREPARATIONS VIEW --- Payload processing workers in the Kennedy Space Center (KSC) Vertical Processing Facility (VPF) prepare to integrate the Space Telescope Imaging Spectrograph (STIS), suspended at center, into the Orbiter Replacement Unit (ORU) Carrier and Scientific Instrument Protective Enclosure (SIPE). STIS will replace the Goddard High Resolution Spectrograph (GHRS) on the Hubble Space Telescope (HST). Four of the seven STS-82 crew members will perform a series of spacewalks to replace two scientific instruments with two new instruments, including STIS, and perform other tasks during the second HST servicing mission. HST was deployed nearly seven years ago and was initially serviced in 1993.

Advances in instrumentation at the W. M. Keck Observatory

NASA Astrophysics Data System (ADS)

Adkins, Sean M.; Armandroff, Taft; Lewis, Hilton; Martin, Chris; McLean, Ian S.; Rockosi, Constance; Wizinowich, Peter

2010-07-01

In this paper we describe both recently completed instrumentation projects and our current development efforts in the context of the Observatory's science driven strategic plan which seeks to address key questions in observational astronomy for extra-galactic, Galactic, and planetary science with both seeing limited capabilities and high angular resolution adaptive optics capabilities. This paper will review recently completed projects as well as new instruments in development including MOSFIRE, a near IR multi-object spectrograph nearing completion, a new seeing limited integral field spectrograph for the visible wavelength range called the Keck Cosmic Web Imager, and the Keck Next Generation Adaptive Optics facility and its first light science instrument DAVINCI.

SpecOp: Optimal Extraction Software for Integral Field Unit Spectrographs

NASA Astrophysics Data System (ADS)

McCarron, Adam; Ciardullo, Robin; Eracleous, Michael

2018-01-01

The Hobby-Eberly Telescope’s new low resolution integral field spectrographs, LRS2-B and LRS2-R, each cover a 12”x6” area on the sky with 280 fibers and generate spectra with resolutions between R=1100 and R=1900. To extract 1-D spectra from the instrument’s 3D data cubes, a program is needed that is flexible enough to work for a wide variety of targets, including continuum point sources, emission line sources, and compact sources embedded in complex backgrounds. We therefore introduce SpecOp, a user-friendly python program for optimally extracting spectra from integral-field unit spectrographs. As input, SpecOp takes a sky-subtracted data cube consisting of images at each wavelength increment set by the instrument’s spectral resolution, and an error file for each count measurement. All of these files are generated by the current LRS2 reduction pipeline. The program then collapses the cube in the image plane using the optimal extraction algorithm detailed by Keith Horne (1986). The various user-selected options include the fraction of the total signal enclosed in a contour-defined region, the wavelength range to analyze, and the precision of the spatial profile calculation. SpecOp can output the weighted counts and errors at each wavelength in various table formats using python’s astropy package. We outline the algorithm used for extraction and explain how the software can be used to easily obtain high-quality 1-D spectra. We demonstrate the utility of the program by applying it to spectra of a variety of quasars and AGNs. In some of these targets, we extract the spectrum of a nuclear point source that is superposed on a spatially extended galaxy.

Thermal hyperspectral chemical imaging

NASA Astrophysics Data System (ADS)

Holma, Hannu; Hyvärinen, Timo; Mattila, Antti-Jussi; Kormano, Ilkka

2012-06-01

Several chemical compounds have their strongest spectral signatures in the thermal region. This paper presents three push-broom thermal hyperspectral imagers. The first operates in MWIR (2.8-5 μm) with 35 nm spectral resolution. It consists of uncooled imaging spectrograph and cryogenically cooled InSb camera, with spatial resolution of 320/640 pixels and image rate to 400 Hz. The second imager covers LWIR in 7.6-12 μm with 32 spectral bands. It employs an uncooled microbolometer array and spectrograph. These imagers have been designed for chemical mapping in reflection mode in industry and laboratory. An efficient line-illumination source has been developed, and it makes possible thermal hyperspectral imaging in reflection with much higher signal and SNR than is obtained from room temperature emission. Application demonstrations including sorting of dark plastics and mineralogical mapping of drill cores are presented. The third imager utilizes a cryo-cooled MCT array with precisely temperature stabilized optics. The optics is not cooled, but instrument radiation is suppressed by special filtering and corrected by BMC (Background-Monitoring-on-Chip) method. The approach provides excellent sensitivity in an instrument which is portable and compact enough for installation in UAVs. The imager has been verified in 7.6 to 12.3 μm to provide NESR of 18 mW/(m2 sr μm) at 10 μm for 300 K target with 100 spectral bands and 384 spatial samples. It results in SNR of higher than 500. The performance makes possible various applications from gas detection to mineral exploration and vegetation surveys. Results from outdoor and airborne experiments are shown.

Technique for diamond machining large ZnSe grisms for the Rapid Infrared/Imager Spectrograph (RIMAS)

NASA Astrophysics Data System (ADS)

Kuzmenko, Paul J.; Little, Steve L.; Kutyrev, Alexander S.; Capone, John I.

2016-07-01

The Rapid Infrared Imager/Spectrograph (RIMAS) is an instrument designed to observe gamma ray burst afterglows following initial detection by the SWIFT satellite. Operating in the near infrared between 0.9 and 2.4 μm, it has capabilities for both low resolution (R 25) and moderate resolution (R 4000) spectroscopy. Two zinc selenide (ZnSe) grisms provide dispersion in the moderate resolution mode: one covers the Y and J bands and the other covers the H and K. Each has a clear aperture of 44 mm. The YJ grism has a blaze angle of 49.9° with a 40 μm groove spacing. The HK grism is blazed at 43.1° with a 50 μm grooves spacing. Previous fabrication of ZnSe grisms on the Precision Engineering Research Lathe (PERL II) at LLNL has demonstrated the importance of surface preparation, tool and fixture design, tight thermal control, and backup power sources for the machine. The biggest challenges in machining the RIMAS grisms are the large grooved area, which indicates long machining time, and the relatively steep blaze angle, which means that the grism wavefront error is much more sensitive to lathe metrology errors. Mitigating techniques are described.

IRMS: Infrared Multi-Slit Spectrograph for TMT

NASA Astrophysics Data System (ADS)

U, Vivian; Mobasher, B.

2014-07-01

As one of the first-light instruments on the TMT, the IRMS is a near-infrared multi-slit spectrograph and imager designed to sample near the diffraction limit with the help of adaptive optics. Fed by the Narrow-Field Infrared Adaptive Optics Systems (NFIRAOS) on the TMT, the IRMS will provide near-infrared imaging and multi-object spectroscopy at Y, J, H, and K bands (0.9-2.5 microns) with moderate spectral resolution. With a field of view of ~2 arcmin on a side, it has a multiplex capability of up to 46 slits using a slit mask system on a cryogenic configurable slit unit. Here we present a preliminary version of the exposure time calculator for sensitivity comparison with Keck/MOSFIRE. Selected science cases are highlighted to demonstrate the need for IRMS in this upcoming thirty-meter class telescope era.

MUSE, the Multi-Slit Solar Explorer

NASA Astrophysics Data System (ADS)

Lemen, J. R.; Tarbell, T. D.; De Pontieu, B.; Wuelser, J. P.

2017-12-01

The Multi-Slit Solar Explorer (MUSE) has been selected for a Phase A study for the NASA Heliophysics Small Explorer program. The science objective of MUSE is to make high spatial and temporal resolution imaging and spectral observations of the solar corona and transition region in order to probe the mechanisms responsible for energy release in the corona and understand the dynamics of the solar atmosphere. The physical processes are responsible for heating the corona, accelerating the solar wind, and the rapid release of energy in CMEs and flares. The observations will be tightly coupled to state-of-the-art numerical modeling to provide significantly improved estimates for understanding and anticipating space weather. MUSE contains two instruments: an EUV spectrograph and an EUV context imager. Both have similar spatial resolutions and leverage extensive heritage from previous high-resolution instruments such as IRIS and the HiC rocket payload. The MUSE spectrograph employs a novel multi-slit design that enables a 100x improvement in spectral scanning rates, which will reveal crucial information about the dynamics (e.g., temperature, velocities) of the physical processes that are not observable with current instruments. The MUSE investigation builds on the success of IRIS by combining numerical modeling with a uniquely capable observatory: MUSE will obtain EUV spectra and images with the highest resolution in space (1/3 arcsec) and time (1-4 s) ever achieved for the transition region and corona, along 35 slits and a large context FOV simultaneously. The MUSE consortium includes LMSAL, SAO, Stanford, ARC, HAO, GSFC, MSFC, MSU, and ITA Oslo.

CIRCE: The Canarias InfraRed Camera Experiment for the Gran Telescopio Canarias

NASA Astrophysics Data System (ADS)

Eikenberry, Stephen S.; Charcos, Miguel; Edwards, Michelle L.; Garner, Alan; Lasso-Cabrera, Nestor; Stelter, Richard D.; Marin-Franch, Antonio; Raines, S. Nicholas; Ackley, Kendall; Bennett, John G.; Cenarro, Javier A.; Chinn, Brian; Donoso, H. Veronica; Frommeyer, Raymond; Hanna, Kevin; Herlevich, Michael D.; Julian, Jeff; Miller, Paola; Mullin, Scott; Murphey, Charles H.; Packham, Chris; Varosi, Frank; Vega, Claudia; Warner, Craig; Ramaprakash, A. N.; Burse, Mahesh; Punnadi, Sunjit; Chordia, Pravin; Gerarts, Andreas; Martín, Héctor De Paz; Calero, María Martín; Scarpa, Riccardo; Acosta, Sergio Fernandez; Sánchez, William Miguel Hernández; Siegel, Benjamin; Pérez, Francisco Francisco; Martín, Himar D. Viera; Losada, José A. Rodríguez; Nuñez, Agustín; Tejero, Álvaro; González, Carlos E. Martín; Rodríguez, César Cabrera; Sendra, Jordi Molgó; Rodriguez, J. Esteban; Cáceres, J. Israel Fernádez; García, Luis A. Rodríguez; Lopez, Manuel Huertas; Dominguez, Raul; Gaggstatter, Tim; Lavers, Antonio Cabrera; Geier, Stefan; Pessev, Peter; Sarajedini, Ata; Castro-Tirado, A. J.

The Canarias InfraRed Camera Experiment (CIRCE) is a near-infrared (1-2.5μm) imager, polarimeter and low-resolution spectrograph operating as a visitor instrument for the Gran Telescopio Canarias (GTC) 10.4-m telescope. It was designed and built largely by graduate students and postdocs, with help from the University of Florida (UF) astronomy engineering group, and is funded by the UF and the US National Science Foundation. CIRCE is intended to help fill the gap in near-infrared capabilities prior to the arrival of Especrografo Multiobjecto Infra-Rojo (EMIR) to the GTC and will also provide the following scientific capabilities to compliment EMIR after its arrival: high-resolution imaging, narrowband imaging, high-time-resolution photometry, imaging polarimetry, and low resolution spectroscopy. In this paper, we review the design, fabrication, integration, lab testing, and on-sky performance results for CIRCE. These include a novel approach to the opto-mechanical design, fabrication, and alignment.

The infrared imaging spectrograph (IRIS) for TMT: reflective ruled diffraction grating performance testing and discussion

NASA Astrophysics Data System (ADS)

Meyer, Elliot; Chen, Shaojie; Wright, Shelley A.; Moore, Anna M.; Larkin, James E.; Simard, Luc; Marie, Jerome; Mieda, Etsuko; Gordon, Jacob

2014-07-01

We present the efficiency of near-infrared reflective ruled diffraction gratings designed for the InfraRed Imaging Spectrograph (IRIS). IRIS is a first light, integral field spectrograph and imager for the Thirty Meter Telescope (TMT) and narrow field infrared adaptive optics system (NFIRAOS). IRIS will operate across the near-infrared encompassing the ZYJHK bands (~0.84 - 2.4μm) with multiple spectral resolutions. We present our experimental setup and analysis of the efficiency of selected reflective diffraction gratings. These measurements are used as a comparison sample against selected candidate Volume Phase Holographic (VPH) gratings (see Chen et al., this conference). We investigate the efficiencies of five ruled gratings designed for IRIS from two separate vendors. Three of the gratings accept a bandpass of 1.19-1.37μm (J band) with ideal spectral resolutions of R=4000 and R=8000, groove densities of 249 and 516 lines/mm, and blaze angles of 9.86° and 20.54° respectively. The other two gratings accept a bandpass of 1.51-1.82μm (H Band) with an ideal spectral resolution of R=4000, groove density of 141 lines/mm, and blaze angle of 9.86°. The fraction of flux in each diffraction mode was compared to both a pure reflection mirror as well as the sum of the flux measured in all observable modes. We measure the efficiencies off blaze angle for all gratings and the efficiencies between the polarization transverse magnetic (TM) and transverse electric (TE) states. The peak reflective efficiencies are 98.90 +/- 3.36% (TM) and 84.99 +/- 2.74% (TM) for the H-band R=4000 and J-band R=4000 respectively. The peak reflective efficiency for the J-band R=8000 grating is 78.78 +/- 2.54% (TE). We find that these ruled gratings do not exhibit a wide dependency on incident angle within +/-3°. Our best-manufactured gratings were found to exhibit a dependency on the polarization state of the incident beam with a ~10-20% deviation, consistent with the theoretical efficiency predictions. This work will significantly contribute to the selection of the final grating type and vendor for the IRIS optical system, and are also pertinent to current and future near-infrared astronomical spectrographs.

WIYN bench upgrade: a revitalized spectrograph

NASA Astrophysics Data System (ADS)

Bershady, M.; Barden, S.; Blanche, P.-A.; Blanco, D.; Corson, C.; Crawford, S.; Glaspey, J.; Habraken, S.; Jacoby, G.; Keyes, J.; Knezek, P.; Lemaire, P.; Liang, M.; McDougall, E.; Poczulp, G.; Sawyer, D.; Westfall, K.; Willmarth, D.

2008-07-01

We describe the redesign and upgrade of the versatile fiber-fed Bench Spectrograph on the WIYN 3.5m telescope. The spectrograph is fed by either the Hydra multi-object positioner or integral-field units (IFUs) at two other ports, and can be configured with an adjustable camera-collimator angle to use low-order and echelle gratings. The upgrade, including a new collimator, charge-coupled device (CCD) and modern controller, and volume-phase holographic gratings (VPHG), has high performance-to-cost ratio by combining new technology with a system reconfiguration that optimizes throughput while utilizing as much of the existing instrument as possible. A faster, all-refractive collimator enhances throughput by 60%, nearly eliminates the slit-function due to vignetting, and improves image quality to maintain instrumental resolution. Two VPH gratings deliver twice the diffraction efficiency of existing surface-relief gratings: A 740 l/mm grating (float-glass and post-polished) used in 1st and 2nd-order, and a large 3300 l/mm grating (spectral resolution comparable to the R2 echelle). The combination of collimator, high-quantum efficiency (QE) CCD, and VPH gratings yields throughput gain-factors of up to 3.5.

Rocket studies of solar corona and transition region. [X-Ray spectrometer/spectrograph telescope

NASA Technical Reports Server (NTRS)

Acton, L. W.; Bruner, E. C., Jr.; Brown, W. A.; Nobles, R. A.

1979-01-01

The XSST (X-Ray Spectrometer/Spectrograph Telescope) rocket payload launched by a Nike Boosted Black Brant was designed to provide high spectral resolution coronal soft X-ray line information on a spectrographic plate, as well as time resolved photo-electric records of pre-selected lines and spectral regions. This spectral data is obtained from a 1 x 10 arc second solar region defined by the paraboloidal telescope of the XSST. The transition region camera provided full disc images in selected spectral intervals originating in lower temperature zones than the emitting regions accessible to the XSST. A H-alpha camera system allowed referencing the measurements to the chromospheric temperatures and altitudes. Payload flight and recovery information is provided along with X-ray photoelectric and UV flight data, transition camera results and a summary of the anomalies encountered. Instrument mechanical stability and spectrometer pointing direction are also examined.

VizieR Online Data Catalog: New FeI level energies from stellar spectra. II. (Peterson+, 2017)

NASA Astrophysics Data System (ADS)

Peterson, R. C.; Kurucz, R. L.; Ayres, T. R.

2017-06-01

All of the new space-based UV spectra were obtained at a two-pixel resolution of 110000 with the E230H echelle grating of the Space Telescope Imaging Spectrograph (STIS) on HST, under program GO-14161 (R. Peterson, PI). See section 2 for further explanations. (2 data files).

VizieR Online Data Catalog: PTF 12dam & iPTF 13dcc follow-up (Vreeswijk+, 2017)

NASA Astrophysics Data System (ADS)

Vreeswijk, P. M.; Leloudas, G.; Gal-Yam, A.; De Cia, A.; Perley, D. A.; Quimby, R. M.; Waldman, R.; Sullivan, M.; Yan, L.; Ofek, E. O.; Fremling, C.; Taddia, F.; Sollerman, J.; Valenti, S.; Arcavi, I.; Howell, D. A.; Filippenko, A. V.; Cenko, S. B.; Yaron, O.; Kasliwal, M. M.; Cao, Y.; Ben-Ami, S.; Horesh, A.; Rubin, A.; Lunnan, R.; Nugent, P. E.; Laher, R.; Rebbapragada, U. D.; Wozniak, P.; Kulkarni, S. R.

2017-08-01

Spectroscopic follow-up observations of PTF 12dam were performed with the Kast Spectrograph at the Lick 3m Shane telescope, and the Low Resolution Imaging Spectrograph (LRIS) at the Keck-I 10m telescope (on Mauna Kea, Hawaii) on 2012 May 20, 21, and 22. The full spectroscopic sequence of PTF 12dam will be presented by R. M. Quimby et al. (2016, in preparation). PTF 12dam was imaged with the Palomar Oschin 48 inch (P48) (i)PTF survey telescope in the Mould R filter, the Palomar 60 inch (P60) and CCD camera in Johnson B and Sloan Digital Sky Survey (SDSS) gri, the Las Cumbres Observatory Global Telescope Network (LCOGT) in SDSS r, and LRIS mounted on the 10m Keck-I telescope in Rs. iPTF 13dcc has not had any exposure in the literature yet. It was flagged as a transient source on 2013 August 29. Spectroscopic follow-up observations spanning 2013 Nov 26 to 2014 Jan 16 were performed with the Double Spectrograph (DBSP) at the Palomar 200 inch (P200), LRIS at Keck-I, and the Inamori-Magellan Areal Camera & Spectrograph (IMACS) at the Magellan Baade telescope, showing iPTF 13dcc to be an SLSN at z=0.4305. iPTF 13dcc was imaged with the P48 Oschin (i)PTF survey telescope in the Mould R filter, the P60 in SDSS gri, the 4.3m Discovery Channel Telescope (DCT, at Lowell Observatory, Arizona) with the Large Monolithic Imager (LMI) in SDSS ri, and finally with the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) Wide-Field Camera using filter F625W (under program GO-13858; P.I. A. De Cia). (3 data files).

VizieR Online Data Catalog: IMF in 3 low-redshift strong lenses from SNELLS (Newman+, 2017)

NASA Astrophysics Data System (ADS)

Newman, A. B.; Smith, R. J.; Conroy, C.; Villaume, A.; van Dokkum, P.

2018-04-01

The SINFONI Nearby Elliptical Lens Locator Survey (SNELLS) lenses (Smith+ 2015MNRAS.449.3441S) were observed using the IMACS spectrograph at the 6.5m Magellan Baade telescope during 2015 April 9-10 and 2015 September 25. Spectroscopic observations cover the wavelength range 3565-9415Å continuously with a uniform resolution of 2.8Å. Total exposure times ranged from 60 minutes to 100 minutes per grating. See section 2.1. All SNELLS lenses were also observed using FIRE, a near-infrared echellete spectrograph at the Magellan Baade telescope, during the nights of 2015 April 8, May 3, and September 25. The FIRE spectra cover 0.82-2.51um, but in this paper we use only the region around the Wing-Ford band of FeH near 9916Å for SNL-0 and SNL-1. On-target exposure times for SNL-0 and SNL-1 were 32 minutes and 54 minutes, respectively. The 1" wide slit provided a resolution of R~4000. See section 2.2. We acquired optical and near-infrared spectra for all the SNELLS lenses with X-shooter at the 8.2m UT2 of the ESO Very Large Telescope (VLT). See section 2.3. We obtained r-band images of SNL-1 and SNL-2 using the LDSS-3 imaging spectrograph at the Magellan 2 telescope. Photometric calibration was tied to the SDSS DR9. For SNL-0, we used Hubble Heritage observations taken with the Advanced Camera for Surveys and the F625W filter (Proposal 10710). When constructing our dynamical model of SNL-2, we also use an R-band image obtained in excellent seeing with FORS2 at the VLT. See section 2.4. (2 data files).

SPRAT: Spectrograph for the Rapid Acquisition of Transients

NASA Astrophysics Data System (ADS)

Piascik, A. S.; Steele, Iain A.; Bates, Stuart D.; Mottram, Christopher J.; Smith, R. J.; Barnsley, R. M.; Bolton, B.

2014-07-01

We describe the development of a low cost, low resolution (R ~ 350), high throughput, long slit spectrograph covering visible (4000-8000) wavelengths. The spectrograph has been developed for fully robotic operation with the Liverpool Telescope (La Palma). The primary aim is to provide rapid spectral classification of faint (V ˜ 20) transient objects detected by projects such as Gaia, iPTF (intermediate Palomar Transient Factory), LOFAR, and a variety of high energy satellites. The design employs a volume phase holographic (VPH) transmission grating as the dispersive element combined with a prism pair (grism) in a linear optical path. One of two peak spectral sensitivities are selectable by rotating the grism. The VPH and prism combination and entrance slit are deployable, and when removed from the beam allow the collimator/camera pair to re-image the target field onto the detector. This mode of operation provides automatic acquisition of the target onto the slit prior to spectrographic observation through World Coordinate System fitting. The selection and characterisation of optical components to maximise photon throughput is described together with performance predictions.

Doppler Imaging and Chemical Abundance Analysis of EK Dra: Capabilities of Small Telescopes

NASA Astrophysics Data System (ADS)

Kilicoglu, Tolgahan; Senavci, H. V.; Bahar, E.; Isik, E.; Montes, D.; Hussain, G. A. J.

2018-04-01

We investigate the chromospheric and spot activity behaviour of the young Solar-like star EK Dra via Doppler imaging and spectral synthesis methods, using mid-resolution time series spectra of the system. We also present the atmospheric parameters and detailed elemental photospheric abundances of the star. The chemical abundance pattern of EK Dra do not suggest any remarkable peculiarities except few elements. The Titanium Oxide (TiO) bandheads at 7000 - 7100 A region also give clues about the spot temperature that may be cooler than 4000 K. In addition, we also discuss the capabilities of small telescopes (40 cm in our case) and medium resolution spectrographs in terms of Doppler imaging and chemical abundance analysis.

Coordinated Ground- and Space-based Multispectral Campaign to Study Equatorial Spread-F Formation

NASA Astrophysics Data System (ADS)

Finn, S. C.; Geddes, G.; Aryal, S.; Stephan, A. W.; Budzien, S. A.; Duggirala, P. R.; Chakrabarti, S.; Valladares, C.

2016-12-01

We present a concept for a multispectral campaign using coordinated data from state-of-the-art instruments aboard the International Space Station (ISS) and multiple ground-based spectrometers and digisondes deployed at low-latitudes to study the formation and development of Equatorial Spread-F (ESF). This extended observational campaign utilizes ultraviolet, visible, and radio measurements to develop a predictive capability for ESF and to study the coupling of the ionosphere-thermosphere (I-T) system during geomagnetically quiet and disturbed times. The ground-based instruments will be deployed in carefully chosen locations in the American and Indian sectors while the space-based data will provide global coverage spanning all local times and longitudes within ±51° geographic latitudes. The campaign, over an extended period covering a range of geophysical conditions, will provide the extensive data base necessary to address the important science questions. The space-based instrument suite consists of the Limb-imaging Ionospheric and Thermospheric Extreme-ultraviolet Spectrograph (LITES) and the GPS Radio Occultation and Ultraviolet Photometry-Colocated (GROUP-C) instruments, scheduled to launch to the ISS in November 2016. LITES is a compact imaging spectrograph for remote sensing of the upper atmosphere and ionosphere from 60 to 140nm and GROUP-C has a nadir-viewing FUV photometer. The ground-based instruments to be deployed for this campaign are three high-resolution imaging spectrographs capable of continuous round-the-clock airglow observations: Multiwavelength Imaging Spectrograph using Echelle grating (MISE) in India and two High Throughput and Multi-slit Imaging Spectrographs (HiT&MIS) to be deployed in Colombia and Argentina, the Low-Latitude Ionosphere Sensor Network (LISN), and the Global Ionospheric Radio Observatory (GIRO) digisondes network. We present data from the ground-based instruments, initial results from the LITES and GROUP-C instruments on-orbit, and modeling and analysis methods for the campaign. This work was supported by NSF 1315354 and 1145166, and ONR N00014-13-1-0266 grants. LITES and GROUP-C are part of the STP-H5 Payload, integrated and flown under the direction of the DoD Space Test Program.

Coronagraph for astronomical imaging and spectrophotometry

NASA Technical Reports Server (NTRS)

Vilas, Faith; Smith, Bradford A.

1987-01-01

A coronagraph designed to minimize scattered light in astronomical observations caused by the structure of the primary mirror, secondary mirror, and secondary support structure of a Cassegrainian telescope is described. Direct (1:1) and reducing (2.7:1) imaging of astronomical fields are possible. High-quality images are produced. The coronagraph can be used with either a two-dimensional charge-coupled device or photographic film camera. The addition of transmission dispersing optics converts the coronagraph into a low-resolution spectrograph. The instrument is modular and portable for transport to different observatories.

Development of television tubes for the large space telescope

NASA Technical Reports Server (NTRS)

Lowrance, J. L.; Zucchino, P.

1971-01-01

Princeton Observatory has been working for several years under NASA sponsorship to develop television type sensors to use in place of photographic film for space astronomy. The performance of an SEC-vidicon with a 25 mm x 25 mm active area, MgF2 window, and bi-alkali photocathode is discussed. Results from ground based use on the Coude spectrograph of the 200-inch Hale telescope are included. The intended use of this tube in an echelle spectrograph sounding rocket payload and on Stratoscope 2 for direct high resolution imagery is also discussed. The paper also discusses the large space telescope image sensor requirements and the development of a larger television tube for this mission.

4MOST optical system: presentation and design details

NASA Astrophysics Data System (ADS)

Azaïs, Nicolas; Frey, Steffen; Bellido, Olga; Winkler, Roland

2017-09-01

The 4-meter Multi-Object Spectroscopic Telescope (4MOST) is a wide-field, high-multiplex spectroscopic survey facility under development for the Visible and Infrared Survey Telescope for Astronomy (VISTA) 4 meter telescope of the European Southern Observatory (ESO) at Cerro Paranal. The objective of 4MOST is to enable the simultaneous spectroscopy of a significant number of targets within a 2.5° diameter field of view, to allow high-efficiency all-sky spectroscopic surveys. A wide field corrector (WFC) is needed to couple targets across the 2.5° field diameter with the exit pupil concentric with the spherical focal surface where 2400 fibres are configured by a fibre positioner (AESOP). For optimal fibre optic coupling and active optics wavefront sensing the WFC will correct optical aberrations of the primary (M1) and secondary (M2) VISTA optics across the full field of view and provide a well-defined and stable focal surface to which the acquisition/guiding sensors, wavefront sensors, and fibre positioner are interfaced. It will also compensate for the effects of atmospheric dispersion, allowing good chromatic coupling of stellar images with the fibre apertures over a wide range of telescope zenith angles (ZD). The fibres feed three spectrographs; two thirds of the fibres will feed two low resolution spectrographs and the remaining 812 fibres will feed a high-resolution spectrograph. The three spectrographs are fixed-configuration with three channels each. We present the 4MOST optical system together with optical simulation of subsystems.

SEEDS Moving Groups and CHARIS Status Updates

NASA Technical Reports Server (NTRS)

McElwain, Michael

2012-01-01

We present the status update for the SEEDS Moving Groups category. To date, we have observed 59 targets and currently have more than 20 candidates. We also present the expected scientific capabilities of CHARIS, the Coronagraphic High Angular Resolution Imaging Spectrograph, which is being built for the Subaru 8.2 m telescope of the National Astronomical Observatory of Japan. CHARIS will be implemented behind the new extreme adaptive optics system at Subaru, SCExAO, and the existing 188-actuator system AO188. CHARIS will offer three observing modes over nearinfrared wavelengths from 0.9 to 2.4 microns (the y-, J-, H-, and K-bands), including a low-spectral-resolution mode covering this entire wavelength range and a high-resolution mode within a single band. With these capabilities, CHARIS will offer exceptional sensitivity for discovering giant exoplanets, and will enable detailed characterization of their atmospheres, CHARIS, the only planned high-contrast integral field spectrograph on an 8m-class telescope in the Northern Hemisphere, will complement the similar instruments such as Project 1640 at Palomar, and GPI and SPHERE in Chile.

Using local correlation tracking to recover solar spectral information from a slitless spectrograph

NASA Astrophysics Data System (ADS)

Courrier, Hans T.; Kankelborg, Charles C.

2018-01-01

The Multi-Order Solar EUV Spectrograph (MOSES) is a sounding rocket instrument that utilizes a concave spherical diffraction grating to form simultaneous images in the diffraction orders m=0, +1, and -1. MOSES is designed to capture high-resolution cotemporal spectral and spatial information of solar features over a large two-dimensional field of view. Our goal is to estimate the Doppler shift as a function of position for every MOSES exposure. Since the instrument is designed to operate without an entrance slit, this requires disentangling overlapping spectral and spatial information in the m=±1 images. Dispersion in these images leads to a field-dependent displacement that is proportional to Doppler shift. We identify these Doppler shift-induced displacements for the single bright emission line in the instrument passband by comparing images from each spectral order. We demonstrate the use of local correlation tracking as a means to quantify these differences between a pair of cotemporal image orders. The resulting vector displacement field is interpreted as a measurement of the Doppler shift. Since three image orders are available, we generate three Doppler maps from each exposure. These may be compared to produce an error estimate.

Calibration Efforts and Unique Capabilities of the HST Space Telescope Imaging Spectrograph

NASA Astrophysics Data System (ADS)

Monroe, TalaWanda R.; Proffitt, Charles R.; Welty, Daniel; Branton, Doug; Carlberg, Joleen K.; debes, John Henry; Lockwood, Sean; Riley, Allyssa; Sohn, Sangmo Tony; Sonnentrucker, Paule G.; Walborn, Nolan R.; Jedrzejewski, Robert I.

2018-01-01

The Space Telescope Imaging Spectrograph (STIS) continues to offer the astronomy community the ability to carry out innovative UV and optical spectroscopic and imaging studies, two decades after its deployment on the Hubble Space Telescope (HST). Most notably, STIS provides spectroscopy in the FUV and NUV, including high spectral resolution echelle modes, imaging in the FUV, optical spectroscopy, and coronagraphic capabilities. Additionally, spatial scanning on the CCD with the long-slits is now possible to enable very high S/N spectroscopic observations without saturation while mitigating telluric and fringing concerns in the far red and near-IR. This new mode may especially benefit the diffuse interstellar bands and exoplanet transiting communities. We present recent calibration efforts for the instrument, including work to optimize the calibration of the echelle spectroscopic modes by improving the flux agreement of overlapping spectral orders affected by changes in the grating blaze function since HST Servicing Mission 4. We also discuss considerations to maintain the wavelength precision of the spectroscopic modes, and the current capabilities of CCD spectroscopic spatial trails.

Focal plane instrument for the Solar UV-Vis-IR Telescope aboard SOLAR-C

NASA Astrophysics Data System (ADS)

Katsukawa, Yukio; Suematsu, Yoshinori; Shimizu, Toshifumi; Ichimoto, Kiyoshi; Takeyama, Norihide

2011-10-01

It is presented the conceptual design of a focal plane instrument for the Solar UV-Vis-IR Telescope (SUVIT) aboard the next Japanese solar mission SOLAR-C. A primary purpose of the telescope is to achieve precise as well as high resolution spectroscopic and polarimetric measurements of the solar chromosphere with a big aperture of 1.5 m, which is expected to make a significant progress in understanding basic MHD processes in the solar atmosphere. The focal plane instrument consists of two packages: A filtergraph package is to get not only monochromatic images but also Dopplergrams and magnetograms using a tunable narrow-band filter and interference filters. A spectrograph package is to perform accurate spectro-polarimetric observations for measuring chromospheric magnetic fields, and is employing a Littrow-type spectrograph. The most challenging aspect in the instrument design is wide wavelength coverage from 280 nm to 1.1 μm to observe multiple chromospheric lines, which is to be realized with a lens unit including fluoride glasses. A high-speed camera for correlation tracking of granular motion is also implemented in one of the packages for an image stabilization system, which is essential to achieve high spatial resolution and high polarimetric accuracy.

Very high-resolution spectroscopy for extremely large telescopes using pupil slicing and adaptive optics.

PubMed

Beckers, Jacques M; Andersen, Torben E; Owner-Petersen, Mette

2007-03-05

Under seeing limited conditions very high resolution spectroscopy becomes very difficult for extremely large telescopes (ELTs). Using adaptive optics (AO) the stellar image size decreases proportional with the telescope diameter. This makes the spectrograph optics and hence its resolution independent of the telescope diameter. However AO for use with ELTs at visible wavelengths require deformable mirrors with many elements. Those are not likely to be available for quite some time. We propose to use the pupil slicing technique to create a number of sub-pupils each of which having its own deformable mirror. The images from all sub-pupils are combined incoherently with a diameter corresponding to the diffraction limit of the sub-pupil. The technique is referred to as "Pupil Slicing Adaptive Optics" or PSAO.

The Stratospheric Observatory for Infrared Astronomy (sofia)

NASA Astrophysics Data System (ADS)

Gehrz, R. D.; Becklin, E. E.

2009-06-01

SOFIA is a 2.5-meter infrared airborne telescope in a Boeing 747-SP that will begin will begin science flights in mid-2009. Flying in the stratosphere at altitudes as high as 45,000 feet, SOFIA will be used to conduct spectroscopic and imaging observations throughout the infrared and sub-mm region with an average transmission of greater than 80 percent. The SOFIA first-generation instrument complement includes broadband imagers, moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. The characteristics and status of the observatory and its instrumentation will be briefly reviewed. SOFIA`s operations schedule and opportunities for observers and instrument developers will be described.

A Post-AGB Star in the Small Magellanic Cloud Observed with the Spitzer Infrared Spectrograph

DTIC Science & Technology

2006-10-23

spectral features, MSX SMC 029, in the Small Magellanic Cloud (SMC) usimg the low-resolution modules of the Infrared Spectrograph on the Spitzer Space ...029, in the Small Magellanic Cloud (SMC) using the low-resolution modules of the Infrared Spectrograph on the Spitzer Space Telescope. A cool dust... outer atmosphere expands and pulsates, pushing gas away from the star where it can cool and condense into dust grains. The resulting circumstellar dust

VizieR Online Data Catalog: The ELM survey. VII. 15 new ELM white dwarf cand. (Brown+, 2016)

NASA Astrophysics Data System (ADS)

Brown, W. R.; Gianninas, A.; Kilic, M.; Kenyon, S. J.; Allende Prieto, C.

2016-05-01

We present observations of 15 new extremely low-mass white dwarf (ELM WD) candidates. Ten objects are selected by color for our targeted spectroscopic ELM Survey program as described in Brown et al. (2012ApJ...744..142B). Five objects come from follow-up spectroscopy of the completed Hypervelocity Star survey. We acquire spectra for the 15 ELM WD candidates using the Blue Channel spectrograph on the 6.5m MMT telescope. We configured the Blue Channel spectrograph to obtain 3650-4500Å spectral coverage with 1.0Å spectral resolution. We acquire additional spectra for 5 objects using the KOSMOS spectrograph on the Kitt Peak National Observatory 4m Mayall telescope on program numbers 2014B-0119 and 2015A-0082. We configured the KOSMOS spectrograph to obtain 3500-6200Å spectral coverage with 2.0Å spectral resolution. We also acquire spectra for objects with g<17mag using the FAST spectrograph on the Fred Lawrence Whipple Observatory 1.5m Tillinghast telescope. We configured the FAST spectrograph to obtain 3500-5500Å spectral coverage with 1.7Å spectral resolution. (3 data files).

The infrared imaging spectrograph (IRIS) for TMT: volume phase holographic grating performance testing and discussion

NASA Astrophysics Data System (ADS)

Chen, Shaojie; Meyer, Elliot; Wright, Shelley A.; Moore, Anna M.; Larkin, James E.; Maire, Jerome; Mieda, Etsuko; Simard, Luc

2014-07-01

Maximizing the grating efficiency is a key goal for the first light instrument IRIS (Infrared Imaging Spectrograph) currently being designed to sample the diffraction limit of the TMT (Thirty Meter Telescope). Volume Phase Holographic (VPH) gratings have been shown to offer extremely high efficiencies that approach 100% for high line frequencies (i.e., 600 to 6000l/mm), which has been applicable for astronomical optical spectrographs. However, VPH gratings have been less exploited in the near-infrared, particularly for gratings that have lower line frequencies. Given their potential to offer high throughputs and low scattered light, VPH gratings are being explored for IRIS as a potential dispersing element in the spectrograph. Our team has procured near-infrared gratings from two separate vendors. We have two gratings with the specifications needed for IRIS current design: 1.51-1.82μm (H-band) to produce a spectral resolution of 4000 and 1.19-1.37μm (J-band) to produce a spectral resolution of 8000. The center wavelengths for each grating are 1.629μm and 1.27μm, and the groove densities are 177l/mm and 440l/mm for H-band R=4000 and J-band R=8000, respectively. We directly measure the efficiencies in the lab and find that the peak efficiencies of these two types of gratings are quite good with a peak efficiency of ~88% at the Bragg angle in both TM and TE modes at H-band, and 90.23% in TM mode, 79.91% in TE mode at J-band for the best vendor. We determine the drop in efficiency off the Bragg angle, with a 20-23% decrease in efficiency at H-band when 2.5° deviation from the Bragg angle, and 25%-28% decrease at J-band when 5° deviation from the Bragg angle.

A fast new cadioptric design for fiber-fed spectrographs

NASA Astrophysics Data System (ADS)

Saunders, Will

2012-09-01

The next generation of massively multiplexed multi-object spectrographs (DESpec, SUMIRE, BigBOSS, 4MOST, HECTOR) demand fast, efficient and affordable spectrographs, with higher resolutions (R = 3000-5000) than current designs. Beam-size is a (relatively) free parameter in the design, but the properties of VPH gratings are such that, for fixed resolution and wavelength coverage, the effect on beam-size on overall VPH efficiency is very small. For alltransmissive cameras, this suggests modest beam-sizes (say 80-150mm) to minimize costs; while for cadioptric (Schmidt-type) cameras, much larger beam-sizes (say 250mm+) are preferred to improve image quality and to minimize obstruction losses. Schmidt designs have benefits in terms of image quality, camera speed and scattered light performance, and recent advances such as MRF technology mean that the required aspherics are no longer a prohibitive cost or risk. The main objections to traditional Schmidt designs are the inaccessibility of the detector package, and the loss in throughput caused by it being in the beam. With expected count rates and current read-noise technology, the gain in camera speed allowed by Schmidt optics largely compensates for the additional obstruction losses. However, future advances in readout technology may erase most of this compensation. A new Schmidt/Maksutov-derived design is presented, which differs from previous designs in having the detector package outside the camera, and adjacent to the spectrograph pupil. The telescope pupil already contains a hole at its center, because of the obstruction from the telescope top-end. With a 250mm beam, it is possible to largely hide a 6cm × 6cm detector package and its dewar within this hole. This means that the design achieves a very high efficiency, competitive with transmissive designs. The optics are excellent, as least as good as classic Schmidt designs, allowing F/1.25 or even faster cameras. The principal hardware has been costed at $300K per arm, making the design affordable.

High-resolution ground-based spectroscopy: where and how ?

NASA Astrophysics Data System (ADS)

Pallavicini, R.

2002-07-01

An overview is presented of high-resolution optical spectrographs in operation or under development at large telescopes, with emphasis on those facilities best suited for the study of late-type stars and stellar surface inhomogeneities. Plans for the development of new high-resolution spectroscopic instruments are discussed with emphasis on the ICE spectrograph for the PEPSI spectropolarimeter at the LBT.

New infrared spectrograph for the investigation of the mesopause region

NASA Astrophysics Data System (ADS)

Koltovskoi, I. I.; Ammosov, P. P.; Gavrilyeva, G. A.; Ammosova, A. M.; Sivseva, V. I.

2017-11-01

A new infrared spectrograph with high temporal resolution for observation of OH band (3-1) emission dynamics is described. For the automated work of the spectrograph, special software was created. Remote control over the device is also configured.

Optical design of the SuMIRe/PFS spectrograph

NASA Astrophysics Data System (ADS)

Pascal, Sandrine; Vives, Sébastien; Barkhouser, Robert; Gunn, James E.

2014-07-01

The SuMIRe Prime Focus Spectrograph (PFS), developed for the 8-m class SUBARU telescope, will consist of four identical spectrographs, each receiving 600 fibers from a 2394 fiber robotic positioner at the telescope prime focus. Each spectrograph includes three spectral channels to cover the wavelength range [0.38-1.26] um with a resolving power ranging between 2000 and 4000. A medium resolution mode is also implemented to reach a resolving power of 5000 at 0.8 um. Each spectrograph is made of 4 optical units: the entrance unit which produces three corrected collimated beams and three camera units (one per spectral channel: "blue, "red", and "NIR"). The beam is split by using two large dichroics; and in each arm, the light is dispersed by large VPH gratings (about 280x280mm). The proposed optical design was optimized to achieve the requested image quality while simplifying the manufacturing of the whole optical system. The camera design consists in an innovative Schmidt camera observing a large field-of-view (10 degrees) with a very fast beam (F/1.09). To achieve such a performance, the classical spherical mirror is replaced by a catadioptric mirror (i.e meniscus lens with a reflective surface on the rear side of the glass, like a Mangin mirror). This article focuses on the optical architecture of the PFS spectrograph and the perfornance achieved. We will first described the global optical design of the spectrograph. Then, we will focus on the Mangin-Schmidt camera design. The analysis of the optical performance and the results obtained are presented in the last section.

Achieving the resolution of the spectrograph of the 6m large Azimuthal telescope

NASA Astrophysics Data System (ADS)

Sazonenko, Dmitrii; Kukushkin, Dmitrii; Bakholdin, Alexey; Valyavin, Gennady

2016-08-01

Special Astrophysical Observatory of Russian Academy of Sciences (SAO RAS) creates a spectrograph with high spectral resolution for the 6-meter telescope. The spectrograph consists of a mobile unit located at the focus of the telescope's main mirror, a stationary part located under the telescope and optical fibers which transmit light from the mobile part to the stationary one. The spectral resolution of the stationary part should be R=100000. To achieve such a value, the scheme has two spectral elements, with cross-dispersion. The main spectral element is an echelle grating. The second spectral element is a prism with a diffraction grating on one facet.

EUNIS-07: First Look

NASA Technical Reports Server (NTRS)

Rabin, Douglas M.; Thomas, Roger J.; Brosius, Jeffrey W.

2008-01-01

The Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS) sounding rocket instrument is a two-channel imaging spectrograph that observes the solar corona with high spectral resolution and a rapid cadence made possible by unprecedented sensitivity. EUNIS flew for the first time on 2006 April 12 (EUNIS-06), returning over 140 science exposures at a cadence of 2.1 s; each exposure comprises six 1K x 1K active pixel sensor (APS) images, three for each wavelength channel (170-205 $\\AA$ and 300-370 $\\AA$). Analysis of EUNIS-06 data has so far shed new light on the nature of coronal bright points, cool transients, and coronal loop arcades and has enabled calibration updates for TRACE and SOHO's CDS and EIT. EUNIS flew successfully again on 2007 November 6 (EUNIS-07). Because the APS's were operated in video rather than snapshot mode, a faster cadence of 1.3 s was possible (97% duty cycle), resulting in 276 science exposures. We present an overview of the EUNIS-07 spectra and describe the coordinated observing program executed by the Hinode Extreme ultraviolet Imaging Spectrograph (EIS) that will, in conjunction with the absolute radiometric calibration of EUNIS-07, result in the first on-orbit radiometric calibration of EIS. EUNIS data are freely available to the solar physics community. EUNIS is supported by the NASA Heliophysics Division through its Low Cost Access to Space Program in Solar and Heliospheric Physics.

VizieR Online Data Catalog: PTF obs. of a precursor to SNHunt 275 2015 May event (Ofek+, 2016)

NASA Astrophysics Data System (ADS)

Ofek, E. O.; Cenko, S. B.; Shaviv, N. J.; Duggan, G.; Strotjohann, N.-L.; Rubin, A.; Kulkarni, S. R.; Gal-Yam, A.; Sullivan, M.; Cao, Y.; Nugent, P. E.; Kasliwal, M. M.; Sollerman, J.; Fransson, C.; Filippenko, A. V.; Perley, D. A.; Yaron, O.; Laher, R.

2016-08-01

The Palomar Transient Factory (PTF and iPTF; Law et al. 2009PASP..121.1395L; Rau et al. 2009PASP..121.1334R), using the 48inch Oschin Schmidt telescope, observed the field of SNHunt 275 starting in 2009 March. On 2013 December 12, PTF detected a new source at the location of the event, and the transient was named PTF 13efv (see Figure 1). Three images obtained between 2014 January 23 and April 25 were used as a reference. The PTF R-band photometry is listed in Table1. Most of the optical spectra were obtained with the Low Resolution Imaging Spectrometer (LRIS) on the Keck I 10m telescope, although a few spectra were also taken with the DEep Imaging Multi-Object Spectrograph (DEIMOS) on the Keck II 10m telescope, the Kast spectrograph on the Shane 3m telescope at Lick Observatory, and the Gemini-North Multiobject Spectrograph (GMOS) on the 8m Gemini-N telescope. The first spectrum was obtained during the 2013 December outburst. We used the Swift/UVOT observations of SNHunt 275, since 2008, to construct the bolometric light curve of the transient. The log of Swift-XRT observations, along with the source and background X-ray counts in the individual observations, is given in Table 5. (3 data files).

The ultra high resolution XUV spectroheliograph: An attached payload for the Space Station Freedom

NASA Technical Reports Server (NTRS)

Walker, Arthur B. C., Jr.; Hoover, Richard B.; Barbee, Troy W., Jr.; Tandberg-Hanssen, Einar; Timothy, J. Gethyn; Lindblom, Joakim F.

1990-01-01

The principle goal of the ultra high resolution XUV spectroheliograph (UHRXS) is to improve the ability to identify and understand the fundamental physical processes that shape the structure and dynamics of the solar chromosphere and corona. The ability of the UHRXS imaging telescope and spectrographs to resolve fine scale structures over a broad wavelength (and hence temperature) range is critical to this mission. The scientific objectives and instrumental capabilities of the UHRXS investigation are reviewed before proceeding to a discussion of the expected performance of the UHRXS observatory.

Designing the optimal semi-warm NIR spectrograph for SALT via detailed thermal analysis

NASA Astrophysics Data System (ADS)

Wolf, Marsha J.; Sheinis, Andrew I.; Mulligan, Mark P.; Wong, Jeffrey P.; Rogers, Allen

2008-07-01

The near infrared (NIR) upgrade to the Robert Stobie Spectrograph (RSS) on the Southern African Large Telescope (SALT), RSS/NIR, extends the spectral coverage of all modes of the optical spectrograph. The RSS/NIR is a low to medium resolution spectrograph with broadband, spectropolarimetric, and Fabry-Perot imaging capabilities. The optical and NIR arms can be used simultaneously to extend spectral coverage from 3200 Å to approximately 1.6 μm. Both arms utilize high efficiency volume phase holographic gratings via articulating gratings and cameras. The NIR camera incorporates a HAWAII-2RG detector with an Epps optical design consisting of 6 spherical elements and providing subpixel rms image sizes of 7.5 +/- 1.0 μm over all wavelengths and field angles. The NIR spectrograph is semi-warm, sharing a common slit plane and partial collimator with the optical arm. A pre-dewar, cooled to below ambient temperature, houses the final NIR collimator optic, the grating/Fabry-Perot etalon, the polarizing beam splitter, and the first three camera optics. The last three camera elements, blocking filters, and detector are housed in a cryogenically cooled dewar. The semi-warm design concept has long been proposed as an economical way to extend optical instruments into the NIR, however, success has been very limited. A major portion of our design effort entails a detailed thermal analysis using non-sequential ray tracing to interactively guide the mechanical design and determine a truly realizable long wavelength cutoff over which astronomical observations will be sky-limited. In this paper we describe our thermal analysis, design concepts for the staged cooling scheme, and results to be incorporated into the overall mechanical design and baffling.

Far-ultraviolet Spectroscopy of Recent Comets with the Cosmic Origins Spectrograph on the Hubble Space Telescope

NASA Astrophysics Data System (ADS)

Feldman, Paul D.; Weaver, Harold A.; A’Hearn, Michael F.; Combi, Michael R.; Dello Russo, Neil

2018-05-01

Since its launch in 1990, the Hubble Space Telescope (HST) has served as a platform with unique capabilities for remote observations of comets in the far-ultraviolet region of the spectrum. Successive generations of imagers and spectrographs have seen large advances in sensitivity and spectral resolution enabling observations of the diverse properties of a representative number of comets during the past 25 years. To date, four comets have been observed in the far-ultraviolet by the Cosmic Origins Spectrograph (COS), the last spectrograph to be installed in HST, in 2009: 103P/Hartley 2, C/2009 P1 (Garradd), C/2012 S1 (ISON), and C/2014 Q2 (Lovejoy). COS has unprecedented sensitivity, but limited spatial information in its 2.″5 diameter circular aperture, and our objective was to determine the CO production rates from measurements of the CO Fourth Positive system in the spectral range of 1400–1700 Å. In the two brightest comets, 19 bands of this system were clearly identified. The water production rates were derived from nearly concurrent observations of the OH (0,0) band at 3085 Å by the Space Telescope Imaging Spectrograph. The derived CO/{{{H}}}2{{O}} production rate ratio ranged from ∼0.3% for Hartley 2 to ∼22% for Garradd. In addition, strong partially resolved emission features due to multiplets of S I, centered at 1429 Å and 1479 Å, and of C I at 1561 Å and 1657 Å, were observed in all four comets. Weak emission from several lines of the {{{H}}}2 Lyman band system, excited by solar Lyα and Lyβ pumped fluorescence, were detected in comet Lovejoy.

VizieR Online Data Catalog: Photospheric properties of T Tauri stars (Herczeg+, 2014)

NASA Astrophysics Data System (ADS)

Herczeg, G. J.; Hillenbrand, L. A.

2017-06-01

We obtained low resolution optical spectra with the Double Spectrograph (DBSP; Oke & Gunn 1982PASP...94..586O) on the Hale 200 inch telescope at Palomar Observatory on 2008 January 18-21 and 2008 December 28-30, and with the Low Resolution Imaging Spectrograph (LRIS; Oke et al. 1995PASP..107..375O; McCarthy et al. 1998SPIE.3355...81M) on Keck I on 2006 November 23 and 2008 May 28. The entire sample of the 2006 Keck observations was published in Herczeg & Hillenbrand (2008ApJ...681..594H). The latest spectral types of the 2008 May run were published in Herczeg et al. (2009ApJ...696.1589H). The Atmospheric Dispersion Corrector (Phillips et al. 2006SPIE.6269E..1OP) was used for the 2008 May run but was not yet available in 2006 November. Both DBSP and LRIS use a dichroic to split the light into red and blue beams at ~5600 Å. (1 data file).

VizieR Online Data Catalog: Silicon depletion in the interstellar medium (Haris+, 2016)

NASA Astrophysics Data System (ADS)

Haris, U.; Parvathi, V. S.; Gudennavar, S. B.; Bubbly, S. G.; Murthy, J.; Sofia, U. J.

2018-03-01

Gudennavar et al. (2012, J/ApJS/199/8) compiled absorption line data for 3008 stars of which 131 sight lines included silicon column densities that were taken over 30 years of observations (Table 1). Most of the silicon lines (84) in our sample have come from van Steenberg & Shull (1988ApJS...67..225V) who used archival observations from the International Ultraviolet Explorer (IUE) to derive column densities to a number of different species. Most of the other observations (36) were made using the Goddard High Resolution Spectrograph (Spitzer & Fitzpatrick 1995ApJ...445..196S; Savage & Sembach 1996ARA&A..34..279S; Redfield & Linsky 2004ApJ...602..776R) or the Space Telescope Imaging Spectrograph (Sonnentrucker et al. 2003ApJ...596..350S; Gnacinski & Krogulec 2006AcA....56..373G; Miller et al. 2007ApJ...659..441M) with higher resolution and better signal-to-noise. (3 data files).

VizieR Online Data Catalog: Sulamitis and Clarissa asteroids spectra (Morate+, 2018)

NASA Astrophysics Data System (ADS)

Morate, D.; de, Leon J.; de Pra, M.; Licandro, J.; Cabrera-Lavers, A.; Campins, H.; Pinilla-Alonso, N.

2017-11-01

A total of 97 low-resolution visible spectra were obtained for the asteroids in the Sulamitis and Clarissa families (64 and 33 objects, respectively), using the Optical System for Imaging and Low Resolution Integrated Spectroscopy (OSIRIS) camera spectrograph at the 10.4m Gran Telescopio Canarias (GTC), located at the El Roque de los Muchachos Observatory (ORM) in La Palma, Canary Islands, Spain. In addition, we obtained three spectra of (752) Sulamitis using the Intermediate Dispersion Spectrograph (IDS) at the 2.5m Isaac Newton Telescope, also located at the ORM in La Palma, as part of program C97 (2015), on July 22, 2015. All the spectra files included here are named ast_ASTEROIDNUMBER.txt, except for the spectra of (752) taken with the INT (named ast752INT.txt). The first column is the wavelength, expressed in microns, and the second column is the reflectance value (which is normalized at 1 at 0.55 microns). (3 data files).

The STIS MAMA status: Current detector performance

NASA Technical Reports Server (NTRS)

Danks, A. C.; Joseph, C.; Bybee, R.; Argebright, V.; Abraham, J.; Kimble, R.; Woodgate, B.

1992-01-01

The STIS (Space Telescope Imaging Spectrograph) is a second generation Hubble instrument scheduled to fly in 1997. Through a variety of modes, the instrument will provide spectral resolutions from R approximately 50 in the objective spectroscopy mode to 100,000 in the high resolution echelle mode in the wavelength region from 115 to 1000 nm. In the UV the instrument employs two MAMA (Multimode Anode Microchannel plate Arrays) 1024 by 1024 pixel detectors, which provide high DQE (Detective Quantum Efficiency), and good dynamic range and resolution. The current progress and performance of these detectors are reported, illustrating that the technology is mature and that the performance is very close to flight requirements.

Immersion Gratings for Infrared High-resolution Spectroscopy

NASA Astrophysics Data System (ADS)

Sarugaku, Yuki; Ikeda, Yuji; Kobayashi, Naoto; Kaji, Sayumi; Sukegawa, Takashi; Sugiyama, Shigeru; Nakagawa, Takao; Arasaki, Takayuki; Kondo, Sohei; Nakanishi, Kenshi; Yasui, Chikako; Kawakita, Hideyo

2016-10-01

High-resolution spectroscopy in the infrared wavelength range is essential for observations of minor isotopologues, such as HDO for water, and prebiotic organic molecules like hydrocarbons/P-bearing molecules because numerous vibrational molecular bands (including non-polar molecules) are located in this wavelength range. High spectral resolution enables us to detect weak lines without spectral line confusion. This technique has been widely used in planetary sciences, e.g., cometary coma (H2O, CO, and organic molecules), the martian atmosphere (CH4, CO2, H2O and HDO), and the upper atmosphere of gas giants (H3+ and organic molecules such as C2H6). Spectrographs with higher resolution (and higher sensitivity) still have a potential to provide a plenty of findings. However, because the size of spectrographs scales with the spectral resolution, it is difficult to realize it.Immersion grating (IG), which is a diffraction grating wherein the diffraction surface is immersed in a material with a high refractive index (n > 2), provides n times higher spectral resolution compared to a reflective grating of the same size. Because IG reduces the size of spectrograph to 1/n compared to the spectrograph with the same spectral resolution using a conventional reflective grating, it is widely acknowledged as a key optical device to realize compact spectrographs with high spectral resolution.Recently, we succeeded in fabricating a CdZnTe immersion grating with the theoretically predicted diffraction efficiency by machining process using an ultrahigh-precision five-axis processing machine developed by Canon Inc. Using the same technique, we completed a practical germanium (Ge) immersion grating with both a reflection coating on the grating surface and the an AR coating on the entrance surface. It is noteworthy that the wide wavelength range from 2 to 20 um can be covered by the two immersion gratings.In this paper, we present the performances and the applications of the immersion gratings, including the development of a long-NIR (2-5um) high-resolution (R=80,000) spectrograph with Ge-immersion grating, VINROUGE, which is a prototype for the TMT MIR instrument.

Can we use adaptive optics for UHR spectroscopy with PEPSI at the LBT?

NASA Astrophysics Data System (ADS)

Sacco, Germano G.; Pallavicini, Roberto; Spano, Paolo; Andersen, Michael; Woche, Manfred F.; Strassmeier, Klaus G.

2004-10-01

We investigate the potential of using adaptive optics (AO) in the V, R, and I bands to reach ultra-high resolution (UHR, R >= 200,000) in echelle spectrographs at 8-10m telescopes. In particular, we investigate the possibility of implementing an UHR mode for the fiber-fed spectrograph PEPSI (Potsdam Echelle Polarimetric and Spectrographic Instrument) being developed for the Large Binocular Telescope (LBT). By simulating the performances of the advanced AO system that will be available at first light at the LBT, and by using first-order estimates of the spectrograph performances, we calculate the total efficiency and signal to noise ratio (SNR) of PEPSI in the AO mode for stars of different magnitudes, different fiber core sizes, and different fractions of incident light diverted to the wavefront sensor. We conclude that AO can provide a significant advantage, of up to a factor ~2 in the V, R and I bands, for stars brighter than mR ~ 12 - 13. However, if these stars are observed at UHR in non-AO mode, slit losses caused by the need to use a very narrow slit can be compensated more effectively by the use of image slicers.

The Cosmic Origins Spectrograph

NASA Astrophysics Data System (ADS)

Green, James C.; Froning, Cynthia S.; Osterman, Steve; Ebbets, Dennis; Heap, Sara H.; Leitherer, Claus; Linsky, Jeffrey L.; Savage, Blair D.; Sembach, Kenneth; Shull, J. Michael; Siegmund, Oswald H. W.; Snow, Theodore P.; Spencer, John; Stern, S. Alan; Stocke, John; Welsh, Barry; Béland, Stéphane; Burgh, Eric B.; Danforth, Charles; France, Kevin; Keeney, Brian; McPhate, Jason; Penton, Steven V.; Andrews, John; Brownsberger, Kenneth; Morse, Jon; Wilkinson, Erik

2012-01-01

The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph with unprecedented sensitivity that was installed into the Hubble Space Telescope (HST) in 2009 May, during HST Servicing Mission 4 (STS-125). We present the design philosophy and summarize the key characteristics of the instrument that will be of interest to potential observers. For faint targets, with flux F λ ≈ 1.0 × 10-14 erg cm-2 s-1 Å-1, COS can achieve comparable signal to noise (when compared to Space Telescope Imaging Spectrograph echelle modes) in 1%-2% of the observing time. This has led to a significant increase in the total data volume and data quality available to the community. For example, in the first 20 months of science operation (2009 September-2011 June) the cumulative redshift pathlength of extragalactic sight lines sampled by COS is nine times than sampled at moderate resolution in 19 previous years of Hubble observations. COS programs have observed 214 distinct lines of sight suitable for study of the intergalactic medium as of 2011 June. COS has measured, for the first time with high reliability, broad Lyα absorbers and Ne VIII in the intergalactic medium, and observed the He II reionization epoch along multiple sightlines. COS has detected the first CO emission and absorption in the UV spectra of low-mass circumstellar disks at the epoch of giant planet formation, and detected multiple ionization states of metals in extra-solar planetary atmospheres. In the coming years, COS will continue its census of intergalactic gas, probe galactic and cosmic structure, and explore physics in our solar system and Galaxy.

Advances in photographic X-ray imaging for solar astronomy

NASA Technical Reports Server (NTRS)

Moses, J. Daniel; Schueller, R.; Waljeski, K.; Davis, John M.

1989-01-01

The technique of obtaining quantitative data from high resolution soft X-ray photographic images produced by grazing incidence optics was successfully developed to a high degree during the Solar Research Sounding Rocket Program and the S-054 X-Ray Spectrographic Telescope Experiment Program on Skylab. Continued use of soft X-ray photographic imaging in sounding rocket flights of the High Resolution Solar Soft X-Ray Imaging Payload has provided opportunities to further develop these techniques. The developments discussed include: (1) The calibration and use of an inexpensive, commercially available microprocessor controlled drum type film processor for photometric film development; (2) The use of Kodak Technical Pan 2415 film and Kodak SO-253 High Speed Holographic film for improved resolution; and (3) The application of a technique described by Cook, Ewing, and Sutton for determining the film characteristics curves from density histograms of the flight film. Although the superior sensitivity, noise level, and linearity of microchannel plate and CCD detectors attracts the development efforts of many groups working in soft X-ray imaging, the high spatial resolution and dynamic range as well as the reliability and ease of application of photographic media assures the continued use of these techniques in solar X-ray astronomy observations.

High resolution broad-band spectroscopy in the NIR using the Triplespec externally dispersed interferometer at the Hale telescope

NASA Astrophysics Data System (ADS)

Erskine, David J.; Edelstein, J.; Sirk, M.; Wishnow, E.; Ishikawa, Y.; McDonald, E.; Shourt, W. V.

2014-07-01

High resolution broad-band spectroscopy at near-infrared wavelengths has been performed using externally dis- persed interferometry (EDI) at the Hale telescope at Mt. Palomar. The EDI technique uses a field-widened Michelson interferometer in series with a dispersive spectrograph, and is able to recover a spectrum with a resolution 4 to 10 times higher than the existing grating spectrograph. This method increases the resolution well beyond the classical limits enforced by the slit width and the detector pixel Nyquist limit and, in principle, decreases the effect of pupil variation on the instrument line-shape function. The EDI technique permits arbi- trarily higher resolution measurements using the higher throughput, lower weight, size, and expense of a lower resolution spectrograph. Observations of many stars were performed with the TEDI interferometer mounted within the central hole of the 200 inch primary mirror. Light from the interferometer was then dispersed by the TripleSpec near-infrared echelle spectrograph. Continuous spectra between 950 and 2450 nm with a resolution as high as ~27,000 were recovered from data taken with TripleSpec at a native resolution of ˜2,700. Aspects of data analysis for interferometric spectral reconstruction are described. This technique has applications in im- proving measurements of high-resolution stellar template spectra, critical for precision Doppler velocimetry using conventional spectroscopic methods. A new interferometer to be applied for this purpose at visible wavelengths is under construction.

MEGARA: the new multi-object and integral field spectrograph for GTC

NASA Astrophysics Data System (ADS)

Carrasco, E.; Páez, G.; Izazaga-Pére, R.; Gil de Paz, A.; Gallego, J.; Iglesias-Páramo, J.

2017-07-01

MEGARA is an optical integral-field unit and multi-object spectrograph for the 10.4m Gran Telescopio Canarias. Both observational modes will provide identical spectral resolutions Rfwhm ˜ 6,000, 12,000 and 18,700. The spectrograph is a collimator-camera system. The unique characteristics of MEGARA in terms of throughput and versatility make this instrument the most efficient tool to date to analyze astrophysical objects at intermediate spectral resolutions. The instrument is currently at the telescope for on-sky commissioning. Here we describe the as-built main characteristics the instrument.

The LUVOIR Ultraviolet Multi-Object Spectrograph (LUMOS): instrument definition and design

NASA Astrophysics Data System (ADS)

France, Kevin; Fleming, Brian; West, Garrett; McCandliss, Stephan R.; Bolcar, Matthew R.; Harris, Walter; Moustakas, Leonidas; O'Meara, John M.; Pascucci, Ilaria; Rigby, Jane; Schiminovich, David; Tumlinson, Jason

2017-08-01

The Large Ultraviolet/Optical/Infrared Surveyor (LUVOIR) is one of four large mission concepts currently undergoing community study for consideration by the 2020 Astronomy and Astrophysics Decadal Survey. LUVOIR is being designed to pursue an ambitious program of exoplanetary discovery and characterization, cosmic origins astrophysics, and planetary science. The LUVOIR study team is investigating two large telescope apertures (9- and 15-meter primary mirror diameters) and a host of science instruments to carry out the primary mission goals. Many of the exoplanet, cosmic origins, and planetary science goals of LUVOIR require high-throughput, imaging spectroscopy at ultraviolet (100 - 400 nm) wavelengths. The LUVOIR Ultraviolet Multi-Object Spectrograph, LUMOS, is being designed to support all of the UV science requirements of LUVOIR, from exoplanet host star characterization to tomography of circumgalactic halos to water plumes on outer solar system satellites. LUMOS offers point source and multi-object spectroscopy across the UV bandpass, with multiple resolution modes to support different science goals. The instrument will provide low (R = 8,000 - 18,000) and medium (R = 30,000 - 65,000) resolution modes across the far-ultraviolet (FUV: 100 - 200 nm) and nearultraviolet (NUV: 200 - 400 nm) windows, and a very low resolution mode (R = 500) for spectroscopic investigations of extremely faint objects in the FUV. Imaging spectroscopy will be accomplished over a 3 × 1.6 arcminute field-of-view by employing holographically-ruled diffraction gratings to control optical aberrations, microshutter arrays (MSA) built on the heritage of the Near Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope (JWST), advanced optical coatings for high-throughput in the FUV, and next generation large-format photon-counting detectors. The spectroscopic capabilities of LUMOS are augmented by an FUV imaging channel (100 - 200nm, 13 milliarcsecond angular resolution, 2 × 2 arcminute field-of-view) that will employ a complement of narrow- and medium-band filters. The instrument definition, design, and development are being carried out by an instrument study team led by the University of Colorado, Goddard Space Flight Center, and the LUVOIR Science and Technology Definition Team. LUMOS has recently completed a preliminary design in Goddard's Instrument Design Laboratory and is being incorporated into the working LUVOIR mission concept. In this proceeding, we describe the instrument requirements for LUMOS, the instrument design, and technology development recommendations to support the hardware required for LUMOS. We present an overview of LUMOS' observing modes and estimated performance curves for effective area, spectral resolution, and imaging performance. Example "LUMOS 100-hour Highlights" observing programs are presented to demonstrate the potential power of LUVOIR's ultraviolet spectroscopic capabilities.

Spectra of Th/Ar and U/Ne hollow cathode lamps for spectrograph calibration

NASA Astrophysics Data System (ADS)

Nave, Gillian; Shlosberg, Ariel; Kerber, Florian; Den Hartog, Elizabeth; Neureiter, Bianca

2018-01-01

Low-current Th/Ar hollow cathode lamps have long been used for calibration of astronomical spectrographs on ground-based telescopes. Thorium is an attractive element for calibration as it has a single isotope, has narrow spectral lines, and has a dense spectrum covering the whole of the visible region. However, the high density of the spectrum that makes it attractive for calibrating high-resolution spectrographs is a detriment for lower resolution spectrographs and this is not obvious by examination of existing linelists. In addition, recent changes in regulations regarding the handling of thorium have led to a degradation in the quality of Th/Ar calibration lamps, with contamination by molecular ThO lines that are strong enough to obscure the calibration lines of interest.We are pursuing two approaches to these problems. First, we have expanded and improved the NIST Standard Reference Database 161, "Spectrum of Th-Ar Hollow Cathode Lamps" to cover the region 272 nm to 5500 nm. Spectra of hollow cathode lamps at up to 3 different currents can now be displayed simultaneously. Interactive zooming and the ability to convolve any of the spectra with a Gaussian or uploaded instrument profile enable the user to see immediately what the spectrum would look like at the particular resolution of their spectrograph. Second, we have measured the spectrum of a recent, contaminated Th/Ar hollow cathode lamp using a high-resolution Echelle spectrograph (Madison Wisconsin) at a resolving power (R~ 250,000). This significantly exceeds the resolving power of most astronomical spectrographs and resolves many of the molecular lines of ThO. With these spectra we are measuring and calibrating the positions of these molecular lines in order to make them suitable for spectrograph calibration.In the near infrared region, U/Ne hollow cathode lamps give a higher density of calibration lines than Th/Ar lamps and will be implemented on the upgraded CRIRES+ spectrograph on ESO’s Very Large Telescope in Chile. A new atlas of the U/Ne spectrum as measured by CRIRES will be presented.

CHARIS Construction Status, Design, and Future Science

NASA Astrophysics Data System (ADS)

Groff, Tyler Dean; Kasdin, N. Jeremy; Peters, Mary Anne; Galvin, Michael; Knapp, Gillian R.; Brandt, Timothy; Loomis, Craig; Carr, Michael; Mede, Kyle; Jarosik, Norman; McElwain, Michael W.; Guyon, Olivier; Jovanovic, Nemanja; Takato, Naruhisa; Hayashi, Masahiko

2015-01-01

Princeton University is funded by the National Astronomical Observatory of Japan to build an integral field spectrograph (IFS) dubbed the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS). CHARIS is part of the ongoing exoplanet science effort at the Subaru Telescope, and will serve as the science imager for the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) and AO188 systems. The principal science goals are disk imaging and high contrast spectra of brown dwarfs and hot Jovian planets across J, H, and K bands. SCExAO is a coronagraphic and wavefront control system that will be capable of extreme adaptive optics and quasi-static speckle suppression. Speckle suppression is meant to reduce the residual speckle to a level that makes it possible to detect planets at very low inner working angles (~80 mas). Even so, CHARIS must mitigate spectral contamination from the residual speckle halo due to crosstalk between the closely packed spectra of the image. CHARIS mitigates crosstalk via an array of field stops behind the lenslet array and carefully toleranced relay optics. This reduces uncertainty in the measured spectrum of the exoplanets by increasing robustness of the spectrograph to nearby bright speckles. Mitigating crosstalk in hardware both improves science and reduces computational overhead. Combined with a detailed wavefront budget this improves the utility of CHARIS in the speckle control loop. Another defining feature of CHARIS is its disperser design. In addition to imaging in individual J, H, and K bands, CHARIS has a fourth mode that images across all three simultaneously. This required an improvement in the linearity of dispersion from 1.15 to 2.38 microns. To do so the CHARIS project has chosen a new high-index dispersing material and characterized its properties at cryogenic temperatures. We present the build status of the spectrograph, including status and viability of operating an H2RG detector directly using a SAM card via gigabit Ethernet over Linux. In addition to the stated and as-built specifications of the instrument hardware, we discuss the future of science impacts of CHARIS at the Subaru telescope.

SOFIA Science Instruments: Commissioning, Upgrades and Future Opportunities

NASA Technical Reports Server (NTRS)

Smith, Erin C.

2014-01-01

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is the world's largest airborne observatory, featuring a 2.5 meter telescope housed in the aft section of a Boeing 747sp aircraft. SOFIA's current instrument suite includes: FORCAST (Faint Object InfraRed CAmera for the SOFIA Telescope), a 5-40 µm dual band imager/grism spectrometer developed at Cornell University; HIPO (High-speed Imaging Photometer for Occultations), a 0.3-1.1 micron imager built by Lowell Observatory; FLITECAM (First Light Infrared Test Experiment CAMera), a 1-5 micron wide-field imager/grism spectrometer developed at UCLA; FIFI-LS (Far-Infrared Field-Imaging Line Spectrometer), a 42-210 micron IFU grating spectrograph completed by University Stuttgart; and EXES (Echelon-Cross- Echelle Spectrograph), a 5-28 micron high-resolution spectrometer being completed by UC Davis and NASA Ames. A second generation instrument, HAWC+ (Highresolution Airborne Wideband Camera), is a 50-240 micron imager being upgraded at JPL to add polarimetry and new detectors developed at GSFC. SOFIA will continually update its instrument suite with new instrumentation, technology demonstration experiments and upgrades to the existing instrument suite. This paper details instrument capabilities and status as well as plans for future instrumentation, including the call for proposals for 3rd generation SOFIA science instruments.

4MOST fiber feed preliminary design: prototype testing and performance

NASA Astrophysics Data System (ADS)

Haynes, Dionne M.; Kelz, Andreas; Barden, Samuel C.; Bauer, Svend-Marian; Ehrlich, Katjana; Haynes, Roger; Jahn, Thomas; Saviauk, Allar; de Jong, Roelof S.

2016-08-01

The 4MOST instrument is a multi-object-spectrograph for the ESO-VISTA telescope. The 4MOST fiber feed subsystem is composed of a fiber positioner (AESOP) holding 2436 science fibers based on the Echidna tilting spine concept, and the fiber cable, which feeds two low-resolution spectrographs (1624 fibers) and one high-resolution spectrograph (812 fibers). In order to optimize the fiber feed subsystem design and provide essential information required for the spectrograph design, prototyping and testing has been undertaken. In this paper we give an overview of the current fiber feed subsystem design and present the preliminary FRD, scrambling, throughput and system performance impact results for: maximum and minimum spine tilt, fiber connectors, cable de-rotator simulator for fiber cable lifetime tests.

Two simple image slicers for high resolution spectroscopy

NASA Astrophysics Data System (ADS)

Tala, M.; Vanzi, L.; Avila, G.; Guirao, C.; Pecchioli, E.; Zapata, A.; Pieralli, F.

2017-04-01

We present the design, manufacturing, test and performance of two image slicers for high resolution spectroscopy. Based on the classical Bowen-Walraven concept, our slicers allow to make two slices of the image of the input fibre. We introduce the idea of a second fibre that can be cropped in half to reach the same width of the science target fibre and that can be used for simultaneous wavelength reference. The slicers presented are mirror and prism based, respectively. Both devices work within expectation, showing differences mainly in their efficiency. The prism based slicer is the solution that was adopted for the FIDEOS spectrograph, an instrument built by the AIUC for the ESO 1m telescope of La Silla. Test spectra obtained with this instrument are included as examples of a real application of the device.

Hubble Space Telescope: Goddard high resolution spectrograph instrument handbook. Version 2.1

NASA Technical Reports Server (NTRS)

Duncan, Douglas K.; Ebbets, Dennis

1990-01-01

The Goddard High Resolution Spectrograph (GHRS) is an ultraviolet spectrometer which has been designed to exploit the imaging and pointing capabilities of the Hubble Space Telescope. It will obtain observations of astronomical sources with greater spectral, spatial and temporal resolution than has been possible with previous space-based instruments. Data from the GHRS will be applicable to many types of scientific investigations, including studies of the interstellar medium, stellar winds, chromospheres and coronae, the byproducts and endproducts of stellar evolution, planetary atmospheres, comets, and many kinds of extragalactic sources. This handbook is intended to introduce the GHRS to potential users. The main purpose is to provide enough information to explore the feasibility of possible research projects and to plan, propose and execute a set of observations. An overview of the instrument performance, which should allow one to evaluate the suitability of the GHRS to specific projects, and a somewhat more detailed description of the GHRS hardware are given. How observing programs will be carried out, the various operating modes of the instrument, and the specific information about the performance of the instrument needed to plan an observation are discussed.

Dwarfs Cooler Than M: The Definition of Spectral Type L Using Discoveries from the 2-Micron All-Sky Survey (2MASS)

NASA Technical Reports Server (NTRS)

Kirkpatrick, J.; Reid, I.; Liebert, J.; Cutri, R.; Nelson, B.; Beichman, C.; Dahn, C.; Monet, D.; Gizis, J.; Skrutskie, M.

1998-01-01

Before the 2-Micron All-Sky Survey (2MASS) began, only six objects were known with spectral types later than M9.5 V. In the first 371 sq. deg. of actual 2MASS survey data, we have identified another twenty such objects spectroscopically confirmed using the Low Resolution Imaging Spectrograph (LRIS) at the W.M. Keck Observatory.

VizieR Online Data Catalog: Double-peaked narrow lines in AGN. II. z<0.1 (Nevin+, 2016)

NASA Astrophysics Data System (ADS)

Nevin, R.; Comerford, J.; Muller-Sanchez, F.; Barrows, R.; Cooper, M.

2017-02-01

To determine the nature of 71 Type 2 AGNs with double-peaked [OIII] emission lines in SDSS that are at z<0.1 and further characterize their properties, we observe them using two complementary follow-up methods: optical long-slit spectroscopy and Jansky Very Large Array (VLA) radio observations. We use various spectrographs with similar pixel scales (Lick Kast Spectrograph; Palomar Double Spectrograph; MMT Blue Channel Spectrograph; APO Dual Imaging Spectrograph and Keck DEep Imaging Multi-Object Spectrograph. We use a 1200 lines/mm grating for all spectrographs; see table 1. In future work, we will combine our long-slit observations with the VLA data for the full sample of 71 galaxies (O. Muller-Sanchez+ 2016, in preparation). (4 data files).

Imaging spectroscopy of Mars in the thermal infrared: seasonal variations of H2O2 and mapping of the D/H ratio

NASA Astrophysics Data System (ADS)

Encrenaz, Therese; DeWitt, Curtis; Richter, Matthew; Greathouse, Thomas; Fouchet, Thierry; Lefevre, Franck; Montmessin, Franck; Forget, Francois; Bezard, Bruno; Atreya, Sushil

2017-04-01

Since 2002, we have been monitoring the spatial distribution and the seasonal variations of H2O2 on Mars, using high-resolution imaging spectroscopy with the Texas Echelon Cross Echelle Spectrograph (TEXES) at the Infrared Telescope Facility (IRTF) at Maunakea Observatory (Hawaii). These observations have shown that a better agreement with global climate models is obtained when heterogeneous chemistry is introduced in the photochemical model (Encrenaz et al. 2015, AA 578, A127). In addition, in April 2014, we have obtained a map of D/H on Mars using the Echelon Cross Echelle Spectrograph (EXES) aboard the stratospheric Observatory for Infrared Astronomy (SOFIA; Encrenaz et al. 2015, AA 586, A62). In 2016, new observations have been obtained on H2O2 with TEXES and on D/H with EXES, allowing us to better analyze the seasonal variations of these parameters. These data will be presented and compared with previous measurements.

MuSICa at GRIS: a prototype image slicer for EST at GREGOR

NASA Astrophysics Data System (ADS)

Calcines, A.; Collados, M.; López, R. L.

2013-05-01

This communication presents a prototype image slicer for the 4-m European Solar Telescope (EST) designed for the spectrograph of the 1.5-m GREGOR solar telescope (GRIS). The design of this integral field unit has been called MuSICa (Multi-Slit Image slicer based on collimator-Camera). It is a telecentric system developed specifically for the integral field, high resolution spectrograph of EST and presents multi-slit capability, reorganizing a bidimensional field of view of 80 arcsec^{2} into 8 slits, each one of them with 200 arcsec length × 0.05 arcsec width. It minimizes the number of optical components needed to fulfil this multi-slit capability, three arrays of mirrors: slicer, collimator and camera mirror arrays (the first one flat and the other two spherical). The symmetry of the layout makes it possible to overlap the pupil images associated to each part of the sliced entrance field of view. A mask with only one circular aperture is placed at the pupil position. This symmetric characteristic offers some advantages: facilitates the manufacturing process, the alignment and reduces the costs. In addition, it is compatible with two modes of operation: spectroscopic and spectro-polarimetric, offering a great versatility. The optical quality of the system is diffraction-limited. The prototype will improve the performances of GRIS at GREGOR and is part of the feasibility study of the integral field unit for the spectrographs of EST. Although MuSICa has been designed as a solar image slicer, its concept can also be applied to night-time astronomical instruments (Collados et al. 2010, Proc. SPIE, Vol. 7733, 77330H; Collados et al. 2012, AN, 333, 901; Calcines et al. 2010, Proc. SPIE, Vol. 7735, 77351X)

Design and early performance of IGRINS (Immersion Grating Infrared Spectrometer)

NASA Astrophysics Data System (ADS)

Park, Chan; Jaffe, Daniel T.; Yuk, In-Soo; Chun, Moo-Young; Pak, Soojong; Kim, Kang-Min; Pavel, Michael; Lee, Hanshin; Oh, Heeyoung; Jeong, Ueejeong; Sim, Chae Kyung; Lee, Hye-In; Nguyen Le, Huynh Anh; Strubhar, Joseph; Gully-Santiago, Michael; Oh, Jae Sok; Cha, Sang-Mok; Moon, Bongkon; Park, Kwijong; Brooks, Cynthia; Ko, Kyeongyeon; Han, Jeong-Yeol; Nah, Jakyoung; Hill, Peter C.; Lee, Sungho; Barnes, Stuart; Yu, Young Sam; Kaplan, Kyle; Mace, Gregory; Kim, Hwihyun; Lee, Jae-Joon; Hwang, Narae; Park, Byeong-Gon

2014-07-01

The Immersion Grating Infrared Spectrometer (IGRINS) is a compact high-resolution near-infrared cross-dispersed spectrograph whose primary disperser is a silicon immersion grating. IGRINS covers the entire portion of the wavelength range between 1.45 and 2.45μm that is accessible from the ground and does so in a single exposure with a resolving power of 40,000. Individual volume phase holographic (VPH) gratings serve as cross-dispersing elements for separate spectrograph arms covering the H and K bands. On the 2.7m Harlan J. Smith telescope at the McDonald Observatory, the slit size is 1ʺ x 15ʺ and the plate scale is 0.27ʺ pixel. The spectrograph employs two 2048 x 2048 pixel Teledyne Scientific and Imaging HAWAII-2RG detectors with SIDECAR ASIC cryogenic controllers. The instrument includes four subsystems; a calibration unit, an input relay optics module, a slit-viewing camera, and nearly identical H and K spectrograph modules. The use of a silicon immersion grating and a compact white pupil design allows the spectrograph collimated beam size to be only 25mm, which permits a moderately sized (0.96m x 0.6m x 0.38m) rectangular cryostat to contain the entire spectrograph. The fabrication and assembly of the optical and mechanical components were completed in 2013. We describe the major design characteristics of the instrument including the system requirements and the technical strategy to meet them. We also present early performance test results obtained from the commissioning runs at the McDonald Observatory.

Hermes: the engineering challenges

NASA Astrophysics Data System (ADS)

Brzeski, Jurek; Gers, Luke; Smith, Greg; Staszak, Nicholas

2012-09-01

The Australian Astronomical Observatory is building a 4-channel VPH-grating High Efficiency and Resolution Multi Element Spectrograph (HERMES) for the 3.9 meter Anglo-Australian Telescope (AAT). HERMES will provide a nominal spectral resolving power of 28,000 for Galactic Archaeology with an optional high-resolution mode of 45,000 with the use of a slit mask. HERMES is fed by a fibre positioning robot called 2dF at the telescope prime focus. There are a total of 784 science fibres, which interface with the spectrograph via two separate slit body assemblies, each comprising of 392 science fibers. The slit defines the spectral lines of 392 fibres on the detector. The width of the detector determines the spectral bandwidth and the detector height determines the fibre to fibre spacing or cross talk. Tolerances that follow from this are all in the 10 micrometer range. The slit relay optics must contribute negligibly to the overall image quality budget and uniformly illuminate the spectrograph exit pupil. The latter requirement effectively requires that the relay optics provide a telecentric input at the collimator entrance slit. As a result it is critical to align the optical components to extreme precision required by the optical design. This paper discusses the engineering challenges of designing, optimising, tolerancing and manufacturing of very precise mechanical components for housing optics and the design of low cost of jigs and fixtures for alignment and assembly of the optics.

VizieR Online Data Catalog: Spectroscopy of candidate members in Taurus (Luhman+, 2017)

NASA Astrophysics Data System (ADS)

Luhman, K. L.; Mamajek, E. E.; Shukla, S. J.; Loutrel, N. P.

2017-06-01

We have obtained optical and near-infrared spectra of candidate members of Taurus. The spectra were collected with the Gemini Near-Infrared Imager (NIRI) using the K-band grism and 0.47'' slit (1.9-2.5μm, R=700), the Gemini Multi-Object Spectrograph (GMOS) using the 400line/mm grating and 0.75'' slit (0.56-1μm, R=1500), the Marcario Low-Resolution Spectrograph (LRS) on the Hobby-Eberly Telescope (HET) using the G3 grism and 2'' slit (0.63-0.91μm, R=1100), and SpeX at the NASA Infrared Telescope Facility (IRTF) using either the prism or SXD mode (R=150/750) and 0.8'' slit (0.8-2.5μm). (7 data files).

The deterministic optical alignment of the HERMES spectrograph

NASA Astrophysics Data System (ADS)

Gers, Luke; Staszak, Nicholas

2014-07-01

The High Efficiency and Resolution Multi Element Spectrograph (HERMES) is a four channel, VPH-grating spectrograph fed by two 400 fiber slit assemblies whose construction and commissioning has now been completed at the Anglo Australian Telescope (AAT). The size, weight, complexity, and scheduling constraints of the system necessitated that a fully integrated, deterministic, opto-mechanical alignment system be designed into the spectrograph before it was manufactured. This paper presents the principles about which the system was assembled and aligned, including the equipment and the metrology methods employed to complete the spectrograph integration.

Experimental Estimation of CLASP Spatial Resolution: Results of the Instrument's Optical Alignment

NASA Technical Reports Server (NTRS)

Giono, Gabrial; Katsukawa, Yukio; Ishikawa, Ryoko; Narukage, Noriyuki; Bando, Takamasa; Kano, Ryohei; Suematsu, Yoshinori; Kobayashi, Ken; Winebarger, Amy; Auchere, Frederic

2015-01-01

The Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) is a sounding-rocket experiment currently being built at the National Astronomical Observatory of Japan. This instrument aims to probe for the first time the magnetic field strength and orientation in the solar upper-chromosphere and lower-transition region. CLASP will measure the polarization of the Lyman-Alpha line (121.6nm) with an unprecedented accuracy, and derive the magnetic field information through the Hanle effect. Although polarization accuracy and spectral resolution are crucial for the Hanle effect detection, spatial resolution is also important to get reliable context image via the slit-jaw camera. As spatial resolution is directly related with the alignment of optics, it is also a good way of ensuring the alignment of the instrument to meet the scientific requirement. This poster will detail the experiments carried out to align CLASP's optics (telescope and spectrograph), as both part of the instrument were aligned separately. The telescope was aligned in double-pass mode, and a laser interferometer (He-Ne) was used to measure the telescope's wavefront error (WFE). The secondary mirror tilt and position were adjusted to remove comas and defocus aberrations from the WFE. Effect of gravity on the WFE measurement was estimated and the final WFE derived in zero-g condition for CLASP telescope will be presented. In addition, an estimation of the spot shape and size derived from the final WFE will also be shown. The spectrograph was aligned with a custom procedure: because Ly-??light is absorbed by air, the spectrograph's off-axis parabolic mirrors were aligned in Visible Light (VL) using a custom-made VL grating instead of the flight Ly-? grating. Results of the alignment in Visible Light will be shown and the spot shape recorded with CCDs at various position along the slit will be displayed. Results from both alignment experiment will be compared to the design requirement, and will be combined in order to estimate CLASP spatial resolution after its alignment in visible light.

The Observing Modes of JWST/NIRISS

NASA Astrophysics Data System (ADS)

Taylor, Joanna M.; NIRISS Team

2018-06-01

The Near Infrared Imager and Slitless Spectrograph (NIRISS) is a contribution of the Canadian Space Agency to the James Webb Space Telescope (JWST). NIRISS complements the other near-infrared science instruments onboard JWST by providing capabilities for (a) low resolution grism spectroscopy between 0.8 and 2.2 µm over the entire field of view, with the possibility of observing the same scene with orthogonal dispersion directions to disentangle blended objects; (b) medium-resolution grism spectroscopy between 0.6 and 2.8 µm that has been optimized to provide high spectrophotometric stability for time-series observations of transiting exoplanets; (c) aperture masking interferometry that provides high angular resolution of 70 - 400 mas at wavelengths between 2.8 and 4.8 µm and (d) parallel imaging through a set of filters that are closely matched to NIRCam's.In this poster, we discuss each of these modes and present simulations of how they might typically be used to address specific scientific questions.

Goddard high resolution spectrograph science verification and data analysis

NASA Technical Reports Server (NTRS)

1992-01-01

The data analysis performed was to support the Orbital Verification (OV) and Science Verification (SV) of the GHRS was in the areas of the Digicon detector's performance and stability, wavelength calibration, and geomagnetic induced image motion. The results of the analyses are briefly described. Detailed results are given in the form of attachments. Specialized software was developed for the analyses. Calibration files were formatted according to the specifications in a Space Telescope Science report. IRAS images were restored of the Large Magellanic Cloud using a blocked iterative algorithm. The algorithm works with the raw data scans without regridding or interpolating the data on an equally spaced image grid.

Correspondence between solar fine-scale structures in the corona, transition region, and lower atmosphere from collaborative observations

NASA Technical Reports Server (NTRS)

Moses, J. Daniel; Cook, J. W.; Bartoe, J.-D. F.; Brueckner, G. E.; Dere, K. P.; Webb, D. F.; Davis, John M.; Recely, F.; Martin, S. F.; Zirin, H.

1989-01-01

The Soft X-Ray Imaging Payload and the High Resolution Telescope and Spectrograph (HRTS) instrument were launched from White Sands on 11 December 1987 in coordinated sounding rocket flights to investigate the correspondence of coronal and transition region structures, especially the relationship between X-ray bright points (XBPs) and transition region small spatial scale energetic events. The coaligned data from X-ray images are presented along with maps of sites of transition region energetic events observed in C IV (100,000 K), HRTS 1600 A spectroheliograms of the T sub min region and ground based magnetogram and He I 10830 A images.

TESIS experiment on XUV imaging spectroscopy of the Sun onboard the CORONAS-PHOTON satellite

NASA Astrophysics Data System (ADS)

Kuzin, S. V.; Zhitnik, I. A.; Bogachev, S. A.; Shestov, S. V.; Bugaenko, O. I.; Suhodrev, N. K.; Pertsov, A. A.; Mitrofanov, A. V.; Ignat'ev, A. P.; Slemzin, V. A.

We present a brief description of new complex of space telescopes and spectrographs, TESIS, which will be placed aboard the CORONAS-PHOTON satellite. The complex is intended for high-resolution imaging observation of full Sun in the coronal spectral lines and in the spectral lines of the solar transition region. TESIS will be launched at the end of 2007 - early of 2008. About 25 % of the daily TESIS images will be free for use and for downloading from the TESIS data center that is planned to open 2 months before the TESIS launching at http://www.tesis.lebedev.ru

Observations of Exoplanets with the Stratospheric Observatory for Infrared Astronomy (SOFIA)

NASA Astrophysics Data System (ADS)

Gehrz, R.; Becklin, E.

2010-10-01

The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (SOFIA) is a 2.5-meter infrared airborne telescope in a Boeing 747-SP that will begin science flights in 2010. Flying in the stratosphere at altitudes as high as 45,000 feet, SOFIA will be used to conduct photometric, spectroscopic, and imaging observations at wavelengths from 0.3 microns to 1.9 millimeters with an average transmission of greater than 80 percent. SOFIA's first-generation instrument complement includes high speed photometers, broadband imagers, moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. These and future instruments will give SOFIA the potential to make unique contributions to the characterization of the atmospheres of exoplanets that transit their parent stars. First-light images obtained on May 26, 2010 with the FORCAST imager will be shown. We will discuss several types of experiments that are being contemplated with respect to observations of exoplanets .

First Solar System Results of the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

VanCleve, J.; Cruikshank, D. P.; Stansberry, J. A.; Burgdorf, M. J.; Devost, D.; Emery, J. P.; Fazio, G.; Fernandez, Y. R.; Glaccum, W.; Grillmair, C.

2004-01-01

The Spitzer Space Telescope, formerly known as SIRTF, is now operational and delivers unprecedented sensitivity for the observation of Solar System targets. Spitzer's capabilities and first general results were presented at the January 2004 AAS meeting. In this poster, we focus on Spitzer's performance for moving targets, and the first Solar System results. Spitzer has three instruments, IRAC, IRS, and MIPS. IRAC (InfraRed Array Camera) provides simultaneous images at wavelengths of 3.6, 4.5, 5.8, and 8.0 microns. IRS (InfraRed Spectrograph) has 4 modules providing low-resolution (R=60-120) spectra from 5.3 to 40 microns, high-resolution (R=600) spectra from 10 to 37 m, and an autonomous target acquisition system (PeakUp) which includes small-field imaging at 15 m. MIPS (Multiband Imaging Photometer for SIRTF) does imaging photometry at 24, 70, and 160 m and low-resolution (R=15-25) spectroscopy (SED) between 55 and 96 microns. Guaranteed Time Observer (GTO) programs include the moons of the outer Solar System, Pluto, Centaurs, Kuiper Belt Objects, and comets

CARMENES in SPIE 2014. Building a fibre link for CARMENES

NASA Astrophysics Data System (ADS)

Stürmer, J.; Stahl, O.; Schwab, C.; Seifert, W.; Quirrenbach, A.; Amado, P. J.; Ribas, I.; Reiners, A.; Caballero, J. A.

2014-07-01

Optical fibres have successfully been used to couple high-resolution spectrographs to telescopes for many years. As they allow the instrument to be placed in a stable and isolated location, they decouple the spectrograph from environmental influences. Fibres also provide a substantial increase in stability of the input illumination of the spectrograph, which makes them a key optical element of the two high-resolution spectrographs of CARMENES. The optical properties of appropriate fibres are investigated, especially their scrambling and focal ratio degradation (FRD) behaviour. In the laboratory the output illumination of various fibres is characterized and different methods to increase the scrambling of the fibre link are tested and compared. In particular, a combination of fibres with different core shapes shows a very good scrambling performance. The near-field (NF) shows an extremely low sensitivity to the exact coupling conditions of the fibre. However, small changes in the far-field (FF) can still be seen. Related optical simulations of the stability performance of the two spectrographs are presented. The simulations focus on the influence of the non-perfect illumination stabilization in the far-field of the fibre on the radial velocity stability of the spectrographs. We use ZEMAX models of the spectrographs to simulate how the barycentres of the spots move depending on the FF illumination pattern and therefore how the radial velocity is affected by a variation of the spectrograph illumination. This method allows to establish a quantitative link between the results of the measurements of the optical properties of fibres on the one hand and the radial velocity precision on the other. The results provide a strong indication that 1ms?1 precision can be reached using a circular-octagonal fibre link even without the use of an optical double scrambler, which has successfully been used in other high-resolution spectrographs. Given the typical throughput of an optical double scrambler of about 75% to 85 %, our solution allows for a substantially higher throughput of the system.

Current Calibration Efforts and Performance of the HST Space Telescope Imaging Spectrograph: Echelle Flux Calibration, the BAR5 Occulter, and Lamp Lifetimes

NASA Astrophysics Data System (ADS)

Monroe, TalaWanda R.; Aloisi, Alessandra; Debes, John H.; Jedrzejewski, Robert I.; Lockwood, Sean A.; Peeples, Molly S.; Proffitt, Charles R.; Riley, Allyssa; Walborn, Nolan R.

2016-06-01

The variety of operating modes of the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) continues to allow STIS users to obtain unique, high quality observations and cutting-edge results 19 years after its installation on HST. STIS is currently the only instrument available to the astronomy community that allows high spectral and spatial resolution spectroscopy in the FUV and NUV, including echelle modes. STIS also supports solar-blind imaging in the FUV. In the optical, STIS provides long-slit, first-order spectra that take advantage of HST's superb spatial resolution, as well as several unique unfiltered coronagraphic modes, which continue to benefit the exoplanet and debris-disk communities. The STIS instrument team monitors the instrument’s health and performance over time to characterize the effects of radiation damage and continued use of the detectors and optical elements. Additionally, the STIS team continues to improve the quality of data products for the user community. We present updates on efforts to improve the echelle flux calibration of overlapping spectral orders due to changes in the grating blaze function since HST Servicing Mission 4, and efforts to push the contrast limit and smallest inner working angle attainable with the coronagraphic BAR5 occulter. We also provide updates on the performance of the STIS calibration lamps, including work to maintain the accuracy of the wavelength calibration for all modes.

Conversational high resolution mass spectrographic data reduction

NASA Technical Reports Server (NTRS)

Romiez, M. P.

1973-01-01

A FORTRAN 4 program is described which reduces the data obtained from a high resolution mass spectrograph. The program (1) calculates an accurate mass for each line on the photoplate, and (2) assigns elemental compositions to each accurate mass. The program is intended for use in a time-shared computing environment and makes use of the conversational aspects of time-sharing operating systems.

GRB 971214

NASA Astrophysics Data System (ADS)

Kulkarni, S. R.; Adelberger, K. L.; Bloom, J. S.; Kundic, T.; Lubin, L.

1998-01-01

On December 28, 1997, Kundic and Lubin obtained spectra of the optical transient of GRB 971214 (IAUC #6788) with the Low Resolution Imaging Spectrograph (LRIS) mounted on the Keck II telescope. The seeing conditions were excellent. If the transient continued the power-law decay as indicated by the data from Halpern et al. (IAUC #6788) then by this epoch the light at this position should be dominated by the host (cf. Kulkarni et al. GCN #27; ATEL #5).

The New Instrument Suite of the TSU/Fairborn 2m Automatic Spectroscopic Telescope

NASA Astrophysics Data System (ADS)

Muterspaugh, Matthew W.; Maxwell, T.; Williamson, M. W.; Fekel, F. C.; Ge, J.; Kelly, J.; Ghasempour, A.; Powell, S.; Zhao, B.; Varosi, F.; Schofield, S.; Liu, J.; Warner, C.; Jakeman, H.; Avner, L.; Swihart, S.; Harrison, C.; Fishler, D.

2014-01-01

Tied with the Liverpool Telescope as the world's largest fully robotic optical research telescope, Tennessee State University's (TSU) 2m Automatic Spectroscopic Telescope (AST) has recently been upgraded to improve performance and increase versatility by supporting multiple instruments. Its second-generation instrument head enables us to rapidly switch between any of up to twelve fibers optics, each of which can supply light to a different instrument. In 2013 construction was completed on a new temperature-controlled guest instrument building, and two new high resolution spectrographs were commissioned. The current set of instrumentation includes (1) the telescope's original R=30,000 echelle spectrograph (0.38--0.83 microns simultaneous), (2) a single order R=7,000 spectrograph centered at Ca H&K features, (3) a single-mode-fiber fed miniature echelle spectrograph (R=100,000; 0.48--0.62 microns simultaneous), (4) the University of Florida's EXPERT-3 spectrograph (R=100,000; 0.38--0.9 microns simultaneous; vacuum and temperature controlled) and (5) the University of Florida's FIRST spectrograph (R=70,000$; 0.8--1.35 or 1.4--1.8 microns simultaneous; vacuum and temperature controlled). Future instruments include the Externally Dispersed Interferometry (EDI) Testbed, a combination low resolution dispersed spectrograph and Fourier Transform Spectrograph. We welcome inquiries from the community in regards to observing access and/or proposals for future guest instruments.

The Ultraviolet Spectrograph on the Europa Mission (Europa-UVS)

NASA Astrophysics Data System (ADS)

Retherford, K. D.; Gladstone, R.; Greathouse, T. K.; Steffl, A.; Davis, M. W.; Feldman, P. D.; McGrath, M. A.; Roth, L.; Saur, J.; Spencer, J. R.; Stern, S. A.; Pope, S.; Freeman, M. A.; Persyn, S. C.; Araujo, M. F.; Cortinas, S. C.; Monreal, R. M.; Persson, K. B.; Trantham, B. J.; Versteeg, M. H.; Walther, B. C.

2015-12-01

NASA's Europa multi-flyby mission is designed to provide a diversity of measurements suited to enrich our understanding of the potential habitability of this intriguing ocean world. The Europa mission's Ultraviolet Spectrograph, Europa-UVS, is the sixth in a series of successful ultraviolet imaging spectrographs (Rosetta-Alice, New Horizons Pluto-Alice, LRO-LAMP) and, like JUICE-UVS (now under Phase B development), is largely based on the most recent of these to fly, Juno-UVS. Europa-UVS observes photons in the 55-210 nm wavelength range, at moderate spectral and spatial resolution along a 7.5° slit. Three distinct apertures send light to the off-axis telescope mirror feeding the long-slit spectrograph: i) a main entrance airglow port is used for most observations (e.g., airglow, aurora, surface mapping, and stellar occultations); ii) a high-spatial-resolution port consists of a small hole in an additional aperture door, and is used for detailed observations of bright targets; and iii) a separate solar port allows for solar occultations, viewing at a 60° offset from the nominal payload boresight. Photon event time-tagging (pixel list mode) and programmable spectral imaging (histogram mode) allow for observational flexibility and optimal science data management. As on Juno-UVS, the effects of penetrating electron radiation on electronic parts and data quality are mitigated through contiguous shielding, filtering of pulse height amplitudes, management of high-voltage settings, and careful use of radiation-hard parts. The science goals of Europa-UVS are to: 1) Determine the composition & chemistry, source & sinks, and structure & variability of Europa's atmosphere, from equator to pole; 2) Search for and characterize active plumes in terms of global distribution, structure, composition, and variability; 3) Explore the surface composition & microphysics and their relation to endogenic & exogenic processes; and 4) Investigate how energy and mass flow in the Europa atmosphere, neutral cloud & plasma torus, and footprint on Jupiter. Here we present the UVS investigation by describing the science we plan to address, the salient details of the instrument, and the basic concept of operations.

Reconstructive correction of aberrations in nuclear particle spectrographs

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

Berz, M.; Joh, K.; Nolen, J.A.

A method is presented that allows the reconstruction of trajectories in particle spectrographs and the reconstructive correction of residual aberrations that otherwise limit the resolution. Using a computed or fitted high order transfer map that describes the uncorrected aberrations of the spectrograph, it is possible to calculate a map via an analytic recursion relation that allows the computation of the corrected data of interest such as reaction energy and scattering angle as well as the reconstructed trajectories in terms of position measurements in two planes near the focal plane. The technique is only limited by the accuracy of the positionmore » measurements, the incoherent spot sizes, and the accuracy of the transfer map. In practice the method can be expressed as an inversion of a nonlinear map and implemented in the differential algebraic framework. The method is applied to correct residual aberrations in the S800 spectrograph which is under construction at the National Superconducting Cyclotron Laboratory at Michigan State University and to two other high resolution spectrographs.« less

A spectrographic study of the aurora and the relation to solar wind pressure pulses.

NASA Astrophysics Data System (ADS)

Stockton-Chalk, A. B.; Lanchester, B. S.; Ivchenko, N.; Lummerzheim, D.; Throp, K.

SIF (Spectrographic Imaging Facility) is a Southampton University / University College London collaboration. The platform consists of a High Throughput Imaging Echelle Spectrograph, HiTIES, two photometers and a narrow angle auroral imager. The spectrograph has a mosaic filter; each of the three spectral panels are centred over/near important spectral features: Hbeta (486.1nm), N2+(470.9nm), N2+(465.2nm), thus allowing studies of proton and electron aurorae. The platform has been successfully deployed in Svalbard since November 1999. The purpose of the experiment was to take spectrographic measurements to study the relationship between proton and electron precipitation and to understand the nature of the precipitating spectrum of protons, both in energy and angular distributions. We present a study of the aurora observed in relation to solar wind pressure pulses.

Research and technology, 1990: Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

1990-01-01

Goddard celebrates 1990 as a banner year in space based astronomy. From above the Earth's obscuring atmosphere, four major orbiting observatories examined the heavens at wavelengths that spanned the electromagnetic spectrum. In the infrared and microwave, the Cosmic Background Explorer (COBE), measured the spectrum and angular distribution of the cosmic background radiation to extraordinary precision. In the optical and UV, the Hubble Space Telescope has returned spectacular high resolution images and spectra of a wealth of astronomical objects. The Goddard High Resolution Spectrograph has resolved dozens of UV spectral lines which are as yet unidentified because they have never before been seen in any astronomical spectrum. In x rays, the Roentgen Satellite has begun returning equally spectacular images of high energy objects within our own and other galaxies.

The 1997 HST Calibration Workshop with a New Generation of Instruments

NASA Technical Reports Server (NTRS)

Casertano, S. (Editor); Jedrzejewski, R. (Editor); Keyes, T. (Editor); Stevens, M. (Editor)

1997-01-01

The Second Servicing mission in early 1997 has brought major changes to the Hubble Space Telescope (HST). Two of the original instruments, Faint Object Spectrograph (FOS) and Goddard High Resolution Spectrograph (GHRS), were taken out, and replaced by completely new instruments, the Space Telescope Imaging Spectrograph (STIS) and the Near Infrared Camera Multi-Object Spectrograph (NICMOS). Two new types of detectors were installed, and for the first time, HST gained infrared capabilities. A new Fine Guidance Sensor (FGS) was installed, with an alignment mechanism that could improve substantially both guiding and astrometric capabilities. With all these changes come new challenges. The characterization of the new instruments has required a major effort, both by their respective Investigation Definition Teams and at the Space Telescope Science Institute. All necessary final calibrations for the retired spectrographs needed to be carried out, and their properties definitively characterized. At the same time, work has continued to improve our understanding of the instruments that have remained on board. The results of these activities were discussed in the 1997 HST (Hubble Space Telescope) Calibration Workshop. The main focus of the Workshop was to provide users with the tools and the understanding they need to use HST's instruments and archival data to the best of their possibilities. This book contains the written record of the Workshop. As such, it should provide a valuable tool to all interested in using existing HST data or in proposing for new observations.

Small Astronomy Payloads for Spacelab. [conferences

NASA Technical Reports Server (NTRS)

Bohlin, R. C. (Editor)

1975-01-01

The workshop to define feasible concepts in the UV-optical 1R area for Astronomy Spacelab Payloads is reported. Payloads proposed include: high resolution spectrograph, Schmidt camera spectrograph, UV telescope, and small infrared cryogenic telescope.

High-contrast imaging with the JWST-NIRSpec Integral Field Unit

NASA Astrophysics Data System (ADS)

Ygouf, M.; Beichman, C.; Hodapp, K.; Roellig, T.

2017-12-01

With its integral field unit, the near-infrared spectrograph NIRSPEC on JWST will allow to measure high-resolution spectra into the 3-\\SI{5}μm range with an increased sensitivity over ground-based systems. This capability will considerably extend our knowledge of brown dwarfs and bright exoplanets at large separations from their host star. But because there is not any coronagraph on NIRSPEC, the performance in term of contrast at close separation will be extremely limited. In this communication, we explore possibilities to further push this limitation by exploiting the wavelength diversity offered by the spectral differential imaging strategy.

Time-of-flight mass spectrographs—From ions to neutral atoms

NASA Astrophysics Data System (ADS)

Möbius, E.; Galvin, A. B.; Kistler, L. M.; Kucharek, H.; Popecki, M. A.

2016-12-01

After their introduction to space physics in the mid 1980s time-of-flight (TOF) spectrographs have become a main staple in spaceborne mass spectrometry. They have largely replaced magnetic spectrometers, except when extremely high mass resolution is required to identify complex molecules, for example, in the vicinity of comets or in planetary atmospheres. In combination with electrostatic analyzers and often solid state detectors, TOF spectrographs have become key instruments to diagnose space plasma velocity distributions, mass, and ionic charge composition. With a variety of implementation schemes that also include isochronous electric field configurations, TOF spectrographs can respond to diverse science requirements. This includes a wide range in mass resolution to allow the separation of medium heavy isotopes or to simply provide distributions of the major species, such as H, He, and O, to obtain information on source tracers or mass fluxes. With a top-hat analyzer at the front end, or in combination with deflectors for three-axis stabilized spacecraft, the distribution function of ions can be obtained with good time resolution. Most recently, the reach of TOF ion mass spectrographs has been extended to include energetic neutral atoms. After selecting the arrival direction with mechanical collimation, followed by conversion to ions, adapted TOF sensors form a new branch of the spectrograph family tree. We review the requirements, challenges, and implementation schemes for ion and neutral atom spectrographs, including potential directions for the future, while largely avoiding overlap with complementary contributions in this special issue.

The extreme ultraviolet spectrograph: A radial groove grating, sounding rocket-borne, astronomical instrument

NASA Technical Reports Server (NTRS)

Wilkinson, Erik; Green, James C.; Cash, Webster

1993-01-01

The design, calibration, and sounding rocket flight performance of a novel spectrograph suitable for moderate-resolution EUV spectroscopy are presented. The sounding rocket-borne instrument uses a radial groove grating to maintain a high system efficiency while controlling the aberrations induced when doing spectroscopy in a converging beam. The instrument has a resolution of approximately 2 A across the 200-330 A bandpass with an average effective area of 2 sq cm. The instrument, called the Extreme Ultraviolet Spectrograph, acquired the first EUV spectra in this wavelength region of the hot white dwarf G191-B2B and the late-type star Capella.

MSE spectrograph optical design: a novel pupil slicing technique

NASA Astrophysics Data System (ADS)

Spanò, P.

2014-07-01

The Maunakea Spectroscopic Explorer shall be mainly devoted to perform deep, wide-field, spectroscopic surveys at spectral resolutions from ~2000 to ~20000, at visible and near-infrared wavelengths. Simultaneous spectral coverage at low resolution is required, while at high resolution only selected windows can be covered. Moreover, very high multiplexing (3200 objects) must be obtained at low resolution. At higher resolutions a decreased number of objects (~800) can be observed. To meet such high demanding requirements, a fiber-fed multi-object spectrograph concept has been designed by pupil-slicing the collimated beam, followed by multiple dispersive and camera optics. Different resolution modes are obtained by introducing anamorphic lenslets in front of the fiber arrays. The spectrograph is able to switch between three resolution modes (2000, 6500, 20000) by removing the anamorphic lenses and exchanging gratings. Camera lenses are fixed in place to increase stability. To enhance throughput, VPH first-order gratings has been preferred over echelle gratings. Moreover, throughput is kept high over all wavelength ranges by splitting light into more arms by dichroic beamsplitters and optimizing efficiency for each channel by proper selection of glass materials, coatings, and grating parameters.

Slit Function Measurement of An Imaging Spectrograph Using Fourier Transform Techniques

NASA Technical Reports Server (NTRS)

Park, Hongwoo; Swimyard, Bruce; Jakobsen, Peter; Moseley, Harvey; Greenhouse, Matthew

2004-01-01

Knowledge of a spectrograph slit function is necessary to interpret the unresolved lines in an observed spectrum. A theoretical slit function can be calculated from the sizes of the entrance slit, the detector aperture when it functions as an exit slit, the dispersion characteristic of the disperser, and the point spread function of the spectrograph. A measured slit function is preferred to the theoretical one for the correct interpretation of the spectral data. In a scanning spectrometer with a single exit slit, the slit function is easily measured. In a fixed grating/or disperser spectrograph, illuminating the entrance slit with a near monochromatic light from a pre-monochrmator or a tunable laser and varying the wavelength of the incident light can measure the slit function. Even though the latter technique had been used successfully for the slit function measurements, it had been very laborious and it would be prohibitive to an imaging spectrograph or a multi-object spectrograph that has a large field of view. We explore an alternative technique that is manageable for the measurements. In the proposed technique, the imaging spectrograph is used as a detector of a Fourier transform spectrometer. This method can be applied not only to an IR spectrograph but also has a potential to a visible/UV spectrograph including a wedge filter spectrograph. This technique will require a blackbody source of known temperature and a bolometer to characterize the interferometer part of the Fourier Transform spectrometer. This pa?er will describe the alternative slit function measurement technique using a Fourier transform spectrometer.

Next Generation Instrumentation for the Very Large Telescope Interferometer

NASA Astrophysics Data System (ADS)

Quirrenbach, A.

The scientific capabilities of the VLT Interferometer can be substantially enhanced through new focal-plane instruments. Many interferometric techniques - astrometry, phase-referenced imaging, nulling, and differential phase measurements - require control of the phase to <~ 1 rad; this capability will be provided at the VLTI by the PRIMA facility. Phase-coherent operation of the VLTI will also make it possible to perform interferometry with spectral resolution up to R ~ 100,000 by building fiber links to the high-resolution spectrographs UVES and CRIRES. These developments will open new approaches to fundamental problems in fields as diverse as extrasolar planets, stellar atmospheres, circumstellar matter, and active galactic nuclei.

Medium resolution spectra of the shuttle glow in the visible region of the spectrum

NASA Technical Reports Server (NTRS)

Viereck, R. A.; Murad, E.; Pike, C. P.; Mende, S. B.; Swenson, G. R.; Culbertson, F. L.; Springer, B. C.

1992-01-01

Recent spectral measurements of the visible shuttle glow (lambda = 400 - 800 nm) at medium resolution (1 nm) reveal the same featureless continuum with a maximum near 680 nm that was reported previously. This is also in good agreement with recent laboratory experiments that attribute the glow to the emissions of NO2 formed by the recombination of O + NO. The data that are presented were taken from the aft flight deck with a hand-held spectrograph and from the shuttle bay with a low-light-level television camera. Shuttle glow images and spectra are presented and compared with laboratory data and theory.

Sodium Laser Guide Star Technique, Spectroscopy and Imaging with Adaptive Optics

NASA Astrophysics Data System (ADS)

Ge, Jian

A sodium laser guide star (LGS) adaptive optics (AO) system developed at Stewart Observatory is to be used at the 6.5m MMT. Annual measurements at Kitt Peak show that the mean mesospheric sodium column density varies from ~2×109cm-2 (summer) to ~5×109cm-2 (winter). The sodium column density also varies by a factor of two during a one hour period. The first simultaneous measurements of sodium LGS brightness, sodium column density and laser power were obtained. The absolute sodium return for a continuous wave circularly polarized beam is 1.2([/pm]0.3)× 106 photons s-1m-2W-1 for the sodium column density of 3.7×109cm-2. Theoretical studies demonstrate that the 6.5m MMT LGS AO can provide Strehl ratios better than 0.15 and about 50% flux concentration within 0.2'' aperture for 1-5.5μm under median seeing. This correction will be available for the full sky. Better Strehl and higher flux concentration can be achieved with natural guide stars, but limited sky coverage. The AO corrected field-of-view is about 60''. The Arizona IR Imager and Echelle Spectrograph (ARIES) was designed to match the 6.5m MMT AO. Detection limits of more than 2 magnitude fainter can be reached with the AO over without the AO. A pre-ARIES wide field near-IR camera was designed, built and tested. The camera provides 1'' images in the near-IR over an 8.5 × 8.5arcmin2 field. The 10-σ detection limit with one minute exposures is 17.9 mag. in the K band. A prototype very high resolution cross-dispersed optical echelle spectrograph was designed and built to match the Starfire Optical Range 1.5m AO images. Interstellar KI 7698A absorption lines have been detected in the spectra of αCyg and ζPer. The spectral resolution is 250.000. About 300A wavelengths were covered in a single exposure. Total detection efficiency of 1% has been achieved. For the first time, a near-single-mode fiber with 10μm core size was applied to transmit the Mt. Wilson 100inch AO corrected beams to a spectrograph. The coupling efficiency of the fiber reached up to 70%. Spectra of αOri were recorded. The spectral resolution is 200,000. The total wavelength coverage is about 650A per exposure.

A Multi-object Exoplanet Detecting Technique

NASA Astrophysics Data System (ADS)

Zhang, K.

2011-05-01

Exoplanet exploration is not only a meaningful astronomical action, but also has a close relation with the extra-terrestrial life. High resolution echelle spectrograph is the key instrument for measuring stellar radial velocity (RV). But with higher precision, better environmental stability and higher cost are required. An improved technique of RV means invented by David J. Erskine in 1997, External Dispersed Interferometry (EDI), can increase the RV measuring precision by combining the moderate resolution spectrograph with a fixed-delay Michelson interferometer. LAMOST with large aperture and large field of view is equipped with 16 multi-object low resolution fiber spectrographs. And these spectrographs are capable to work in medium resolution mode (R=5{K}˜10{K}). LAMOST will be one of the most powerful exoplanet detecting systems over the world by introducing EDI technique. The EDI technique is a new technique for developing astronomical instrumentation in China. The operating theory of EDI was generally verified by a feasibility experiment done in 2009. And then a multi-object exoplanet survey system based on LAMOST spectrograph was proposed. According to this project, three important tasks have been done as follows: Firstly, a simulation of EDI operating theory contains the stellar spectrum model, interferometer transmission model, spectrograph mediation model and RV solution model. In order to meet the practical situation, two detecting modes, temporal and spatial phase-stepping methods, are separately simulated. The interference spectrum is analyzed with Fourier transform algorithm and a higher resolution conventional spectrum is resolved. Secondly, an EDI prototype is composed of a multi-object interferometer prototype and the LAMOST spectrograph. Some ideas are used in the design to reduce the effect of central obscuration, for example, modular structure and external/internal adjusting frames. Another feasibility experiment was done at Xinglong Station in 2010. A related spectrum reduction program and the instrumental stability were tested by obtaining some multi-object interference spectrum. Thirdly, studying the parameter optimization of fixed-delay Michelson interferometer is helpful to increase its inner thermal stability and reduce the external environmental requirement. Referring to Wide-angle Michelson Interferometer successfully used in Upper Atmospheric Wind field, a glass pair selecting scheme is given. By choosing a suitable glass pair of interference arms, the RV error can be stable as several hundred m\\cdots^{-1}\\cdot{dg}C^{-1}. Therefore, this work is helpful to deeply study EDI technique and speed up the development of multi-object exoplanet survey system. LAMOST will make a greater contribution to astronomy when the combination between its spectrographs and EDI technique comes true.

Vacuum Predisperser For A Large Plane-Grating Spectrograph

NASA Astrophysics Data System (ADS)

Engleman, R.; Palmer, B. A.; Steinhaus, D. W.

1980-11-01

A plane grating predisperser has been constructed which acts as an "order-sorter" for a large plane-grating spectrograph. This combination can photograph relatively wide regions of spectra in a single exposure with no loss of resolution.

Design, development, and performance of the fibres of MOONS

NASA Astrophysics Data System (ADS)

Guinouard, Isabelle; Avila, Gerardo; Lee, David; Amans, Jean-Philippe; Rees, Phil; Taylor, William; Oliva, Ernesto

2016-07-01

The Multi-Object Optical and Near-infrared Spectrograph (MOONS) will exploit the full 500 square arcmin field of view offered by the Nasmyth focus of the Very Large Telescope and will be equipped with two identical triple arm cryogenic spectrographs covering the wavelength range 0.64μm-1.8μm, with a multiplex capability of over 1000 fibres. Each spectrograph will produce spectra for 500 targets simultaneously, each with its own dedicated sky fibre for optimal sky subtraction. The system will have both a medium resolution (R 4000-6000) mode and a high resolution (R 20000) mode. The fibres are used to pick off each sub field of 1" and are used to transport the light from the instrument focal plane to the two spectrographs. Each fibre has a microlens to focus the beam into the fibre at a relative fast focal ratio of F/3.65 to reduce the Focal Ratio Degradation (FRD).

The Diffuse Interstellar Cloud Experiment: a high-resolution far-ultraviolet spectrograph.

PubMed

Schindhelm, Eric; Beasley, Matthew; Burgh, Eric B; Green, James C

2012-03-01

We have designed, assembled, and launched a sounding rocket payload to perform high-resolution far-ultraviolet spectroscopy. The instrument is functionally a Cassegrain telescope followed by a modified Rowland spectrograph. The spectrograph was designed to achieve a resolving power (R=λ/δλ) of 60,000 in a compact package by adding a magnifying secondary optic. This is enabled by using a holographically ruled grating to minimize aberrations induced by the second optic. We designed the instrument to observe two stars on opposing sides of a nearby hot/cold gas interface. Obtaining spectra of the O VI doublet in absorption toward these stars can provide new insight into the processes governing hot gas in the local interstellar medium. Here we present the optical design and alignment of the telescope and spectrograph, as well as flight results. © 2012 Optical Society of America

Performance of a laser frequency comb calibration system with a high-resolution solar echelle spectrograph

NASA Astrophysics Data System (ADS)

Doerr, H.-P.; Kentischer, T. J.; Steinmetz, T.; Probst, R. A.; Franz, M.; Holzwarth, R.; Udem, Th.; Hänsch, T. W.; Schmidt, W.

2012-09-01

Laser frequency combs (LFC) provide a direct link between the radio frequency (RF) and the optical frequency regime. The comb-like spectrum of an LFC is formed by exact equidistant laser modes, whose absolute optical frequencies are controlled by RF-references such as atomic clocks or GPS receivers. While nowadays LFCs are routinely used in metrological and spectroscopic fields, their application in astronomy was delayed until recently when systems became available with a mode spacing and wavelength coverage suitable for calibration of astronomical spectrographs. We developed a LFC based calibration system for the high-resolution echelle spectrograph at the German Vacuum Tower Telescope (VTT), located at the Teide observatory, Tenerife, Canary Islands. To characterize the calibration performance of the instrument, we use an all-fiber setup where sunlight and calibration light are fed to the spectrograph by the same single-mode fiber, eliminating systematic effects related to variable grating illumination.

High Resolution Spectrograph for the Hobby-Eberly Telescope

NASA Astrophysics Data System (ADS)

Tull, R. G.; MacQueen, P. J.; Good, J.; Epps, H. W.; HET HRS Team

1998-12-01

A fiber fed high-resolution spectrograph (HRS) is under construction for the Hobby-Eberly Telescope (HET). The primary resolving power originally specified, from astrophysical considerations, was R = 60,000 with a fiber of diameter at least 1 arc-second, with full spectral coverage limited only by the combined band-pass of the HET, the optical fiber, and the image detector. This was achieved in the final design with a high blaze angle R-4 echelle mosaic, white pupil design, image slicing, and a large area CCD mosaic illuminated by an eight element refractive camera. Two back-to-back, user selectable first-order diffraction gratings are employed for cross dispersion, to separate echelle spectral orders; the entire spectral range (420 - 1,000 nm) can be covered in as few as two exposures. Critical issues addressed in the design are cross dispersion and order spacing, sky subtraction, echelle and CCD selection, fiber optic feed and scrambling, and image or pupil slicing. In the final design meeting the requirements we exploited the large-area 4096 square CCD, image slicing, and the optical performance of the white-pupil design to acquire a range of 30,000 < R < 120,000 with fibers of diameter 2 and 3 arc-seconds, without sacrificing full spectral coverage. Design details will be presented. Limiting magnitude is projected to be about V = 19 (for S/N = 10) at the nominal R = 60,000 resolving power. The poster display will outline performance characteristics expected in relation to projected astrophysical research capabilities outlined by Sneden et al., in this conference. HRS is supported by generous grants from NSF, NASA, the State of Texas, and private philanthropy, with matching funds granted by the University of Texas and by McDonald Observatory.

Emirates Mars Ultraviolet Spectrometer (EMUS) Overview from the Emirates Mars Mission

NASA Astrophysics Data System (ADS)

Lootah, F. H.; Almatroushi, H. R.; AlMheiri, S.; Holsclaw, G.; Deighan, J.; Chaffin, M.; Reed, H.; Lillis, R. J.; Fillingim, M. O.; England, S.

2017-12-01

The Emirates Mars Ultraviolet Spectrometer (EMUS) instrument is one of three science instruments on board the "Hope Probe" of the Emirates Mars Mission (EMM). EMM is a United Arab Emirates' (UAE) mission to Mars, launching in 2020, to explore the global dynamics of the Martian atmosphere, while sampling on both diurnal and seasonal timescales. The EMUS instrument is a far-ultraviolet imaging spectrograph that measures emissions in the spectral range 100-170 nm. Using a combination of its one-dimensional imaging and spacecraft motion, it will build up two-dimensional far-ultraviolet images of the Martian disk and near-space environment at several important wavelengths: the Lyman beta atomic hydrogen emission (102.6 nm), the Lyman alpha atomic hydrogen emission (121.6 nm), two atomic oxygen emissions (130.4 nm and 135.6 nm), and the carbon monoxide fourth positive group band emission (140 nm-170 nm). Radiances at these wavelengths will be used to derive the column abundance of atomic oxygen, and carbon monoxide in the Martian thermosphere, and the density of atomic oxygen and atomic hydrogen in the Martian exosphere both with spatial and sub-seasonal variability. The EMUS instrument consists of a single telescope mirror feeding a Rowland circle imaging spectrograph with selectable spectral resolution (1.3 nm, 1.8 nm, or 5 nm), and a photon-counting and locating detector (provided by the Space Sciences Laboratory at the University of California, Berkeley). The EMUS spatial resolution of less than 300 km on the disk is sufficient to characterize spatial variability in the Martian thermosphere (100-200 km altitude) and exosphere (>200 km altitude). The instrument is jointly developed by the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder and Mohammed Bin Rashid Space Centre (MBRSC) in Dubai, UAE.

SPICA, Stellar Parameters and Images with a Cophased Array: a 6T visible combiner for the CHARA array.

PubMed

Mourard, Denis; Bério, Philippe; Perraut, Karine; Clausse, Jean-Michel; Creevey, Orlagh; Martinod, Marc-Antoine; Meilland, Anthony; Millour, Florentin; Nardetto, Nicolas

2017-05-01

High angular resolution studies of stars in the optical domain have highly progressed in recent years. After the results obtained with the visible instrument Visible spEctroGraph and polArimeter (VEGA) on the Center for High Angular Resolution Astronomy (CHARA) array and the recent developments on adaptive optics and fibered interferometry, we have started the design and study of a new six-telescope visible combiner with single-mode fibers. It is designed as a low spectral resolution instrument for the measurement of the angular diameter of stars to make a major step forward in terms of magnitude and precision with respect to the present situation. For a large sample of bright stars, a medium spectral resolution mode will allow unprecedented spectral imaging of stellar surfaces and environments for higher accuracy on stellar/planetary parameters. To reach the ultimate performance of the instrument in terms of limiting magnitude (Rmag≃8 for diameter measurements and Rmag≃4 to 5 for imaging), Stellar Parameters and Images with a Cophased Array (SPICA) includes the development of a dedicated fringe tracking system in the H band to reach "long" (200 ms to 30 s) exposures of the fringe signal in the visible.

Spectrum of Th-Ar Hollow Cathode Lamps

National Institute of Standards and Technology Data Gateway

SRD 161 NIST Spectrum of Th-Ar Hollow Cathode Lamps (Web, free access)   This atlas presents observations of the infra-red (IR) spectrum of a low current Th-Ar hollow cathode lamp with the 2-m Fourier transform spectrometer (FTS) at NIST. These observations establish more than 2400 lines that are suitable for use as wavelength standards in the range 691 nm to 5804 nm. The observations were made in collaboration with the European Southern Observatory (ESO), in order to provide calibration reference data for new high-resolution Echelle spectrographs, such as the Cryogenic High-Resolution IR Echelle Spectrograph ([CRIRES]), ESO's new IR spectrograph at the Very Large Telescope in Chile.

DYNAMICS OF ON-DISK PLUMES AS OBSERVED WITH THE INTERFACE REGION IMAGING SPECTROGRAPH, THE ATMOSPHERIC IMAGING ASSEMBLY, AND THE HELIOSEISMIC AND MAGNETIC IMAGER

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

Pant, Vaibhav; Mazumder, Rakesh; Banerjee, Dipankar

2015-07-01

We examine the role of small-scale transients in the formation and evolution of solar coronal plumes. We study the dynamics of plume footpoints seen in the vicinity of a coronal hole using the Atmospheric Imaging Assembly (AIA) images, the Helioseismic and Magnetic Imager magnetogram on board the Solar Dynamics Observatory and spectroscopic data from the Interface Region Imaging Spectrograph (IRIS). Quasi-periodic brightenings are observed in the base of the plumes and are associated with magnetic flux changes. With the high spectral and spatial resolution of IRIS, we identify the sources of these oscillations and try to understand what role themore » transients at the footpoints can play in sustaining the coronal plumes. IRIS “sit-and-stare” observations provide a unique opportunity to study the evolution of footpoints of the plumes. We notice enhanced line width and intensity, and large deviation from the average Doppler shift in the line profiles at specific instances, which indicate the presence of flows at the footpoints of plumes. We propose that outflows (jet-like features) as a result of small-scale reconnections affect the line profiles. These jet-like features may also be responsible for the generation of propagating disturbances (PDs) within the plumes, which are observed to be propagating to larger distances as recorded from multiple AIA channels. These PDs can be explained in terms of slow magnetoacoustic waves.« less

Progress with the Prime Focus Spectrograph for the Subaru Telescope: a massively multiplexed optical and near-infrared fiber spectrograph

NASA Astrophysics Data System (ADS)

Sugai, Hajime; Tamura, Naoyuki; Karoji, Hiroshi; Shimono, Atsushi; Takato, Naruhisa; Kimura, Masahiko; Ohyama, Youichi; Ueda, Akitoshi; Aghazarian, Hrand; de Arruda, Marcio V.; Barkhouser, Robert H.; Bennett, Charles L.; Bickerton, Steve; Bozier, Alexandre; Braun, David F.; Bui, Khanh; Capocasale, Christopher M.; Carr, Michael A.; Castilho, Bruno; Chang, Yin-Chang; Chen, Hsin-Yo; Chou, Richard C. Y.; Dawson, Olivia R.; Dekany, Richard G.; Ek, Eric M.; Ellis, Richard S.; English, Robin J.; Ferrand, Didier; Ferreira, Décio; Fisher, Charles D.; Golebiowski, Mirek; Gunn, James E.; Hart, Murdock; Heckman, Timothy M.; Ho, Paul T. P.; Hope, Stephen; Hovland, Larry E.; Hsu, Shu-Fu; Hu, Yen-Sang; Huang, Pin Jie; Jaquet, Marc; Karr, Jennifer E.; Kempenaar, Jason G.; King, Matthew E.; Le Fèvre, Olivier; Le Mignant, David; Ling, Hung-Hsu; Loomis, Craig; Lupton, Robert H.; Madec, Fabrice; Mao, Peter; Marrara, Lucas S.; Ménard, Brice; Morantz, Chaz; Murayama, Hitoshi; Murray, Graham J.; de Oliveira, Antonio Cesar; de Oliveira, Claudia M.; de Oliveira, Ligia S.; Orndorff, Joe D.; de Paiva Vilaça, Rodrigo; Partos, Eamon J.; Pascal, Sandrine; Pegot-Ogier, Thomas; Reiley, Daniel J.; Riddle, Reed; Santos, Leandro; dos Santos, Jesulino B.; Schwochert, Mark A.; Seiffert, Michael D.; Smee, Stephen A.; Smith, Roger M.; Steinkraus, Ronald E.; Sodré, Laerte; Spergel, David N.; Surace, Christian; Tresse, Laurence; Vidal, Clément; Vives, Sebastien; Wang, Shiang-Yu; Wen, Chih-Yi; Wu, Amy C.; Wyse, Rosie; Yan, Chi-Hung

2014-07-01

The Prime Focus Spectrograph (PFS) is an optical/near-infrared multi-fiber spectrograph with 2394 science fibers, which are distributed in 1.3 degree diameter field of view at Subaru 8.2-meter telescope. The simultaneous wide wavelength coverage from 0.38 μm to 1.26 μm, with the resolving power of 3000, strengthens its ability to target three main survey programs: cosmology, Galactic archaeology, and galaxy/AGN evolution. A medium resolution mode with resolving power of 5000 for 0.71 μm to 0.89 μm also will be available by simply exchanging dispersers. PFS takes the role for the spectroscopic part of the Subaru Measurement of Images and Redshifts (SuMIRe) project, while Hyper Suprime-Cam (HSC) works on the imaging part. HSC's excellent image qualities have proven the high quality of the Wide Field Corrector (WFC), which PFS shares with HSC. The PFS collaboration has succeeded in the project Preliminary Design Review and is now in a phase of subsystem Critical Design Reviews and construction. To transform the telescope plus WFC focal ratio, a 3-mm thick broad-band coated microlens is glued to each fiber tip. The microlenses are molded glass, providing uniform lens dimensions and a variety of refractive-index selection. After successful production of mechanical and optical samples, mass production is now complete. Following careful investigations including Focal Ratio Degradation (FRD) measurements, a higher transmission fiber is selected for the longest part of cable system, while one with a better FRD performance is selected for the fiber-positioner and fiber-slit components, given the more frequent fiber movements and tightly curved structure. Each Fiber positioner consists of two stages of piezo-electric rotary motors. Its engineering model has been produced and tested. After evaluating the statistics of positioning accuracies, collision avoidance software, and interferences (if any) within/between electronics boards, mass production will commence. Fiber positioning will be performed iteratively by taking an image of artificially back-illuminated fibers with the Metrology camera located in the Cassegrain container. The camera is carefully designed so that fiber position measurements are unaffected by small amounts of high special-frequency inaccuracies in WFC lens surface shapes. Target light carried through the fiber system reaches one of four identical fast-Schmidt spectrograph modules, each with three arms. All optical glass blanks are now being polished. Prototype VPH gratings have been optically tested. CCD production is complete, with standard fully-depleted CCDs for red arms and more-challenging thinner fully-depleted CCDs with blue-optimized coating for blue arms. The active damping system against cooler vibration has been proven to work as predicted, and spectrographs have been designed to avoid small possible residual resonances.

PEPSI: The high-resolution échelle spectrograph and polarimeter for the Large Binocular Telescope

NASA Astrophysics Data System (ADS)

Strassmeier, K. G.; Ilyin, I.; Järvinen, A.; Weber, M.; Woche, M.; Barnes, S. I.; Bauer, S.-M.; Beckert, E.; Bittner, W.; Bredthauer, R.; Carroll, T. A.; Denker, C.; Dionies, F.; DiVarano, I.; Döscher, D.; Fechner, T.; Feuerstein, D.; Granzer, T.; Hahn, T.; Harnisch, G.; Hofmann, A.; Lesser, M.; Paschke, J.; Pankratow, S.; Plank, V.; Plüschke, D.; Popow, E.; Sablowski, D.

2015-05-01

PEPSI is the bench-mounted, two-arm, fibre-fed and stabilized Potsdam Echelle Polarimetric and Spectroscopic Instrument for the 2×8.4 m Large Binocular Telescope (LBT). Three spectral resolutions of either 43 000, 120 000 or 270 000 can cover the entire optical/red wavelength range from 383 to 907 nm in three exposures. Two 10.3k×10.3k CCDs with 9-μm pixels and peak quantum efficiencies of 94-96 % record a total of 92 échelle orders. We introduce a new variant of a wave-guide image slicer with 3, 5, and 7 slices and peak efficiencies between 92-96 %. A total of six cross dispersers cover the six wavelength settings of the spectrograph, two of them always simultaneously. These are made of a VPH-grating sandwiched by two prisms. The peak efficiency of the system, including the telescope, is 15 % at 650 nm, and still 11 % and 10 % at 390 nm and 900 nm, respectively. In combination with the 110 m2 light-collecting capability of the LBT, we expect a limiting magnitude of ≈ 20th mag in V in the low-resolution mode. The R = 120 000 mode can also be used with two, dual-beam Stokes IQUV polarimeters. The 270 000-mode is made possible with the 7-slice image slicer and a 100-μm fibre through a projected sky aperture of 0.74 arcsec, comparable to the median seeing of the LBT site. The 43 000-mode with 12-pixel sampling per resolution element is our bad seeing or faint-object mode. Any of the three resolution modes can either be used with sky fibers for simultaneous sky exposures or with light from a stabilized Fabry-Pérot étalon for ultra-precise radial velocities. CCD-image processing is performed with the dedicated data-reduction and analysis package PEPSI-S4S. Its full error propagation through all image-processing steps allows an adaptive selection of parameters by using statistical inferences and robust estimators. A solar feed makes use of PEPSI during day time and a 500-m feed from the 1.8 m VATT can be used when the LBT is busy otherwise. In this paper, we present the basic instrument design, its realization, and its characteristics. Some pre-commissioning first-light spectra shall demonstrate the basic functionality.

Spectrographs for astrophotonics.

PubMed

Blind, N; Le Coarer, E; Kern, P; Gousset, S

2017-10-30

The next generation of extremely large telescopes (ELT), with diameters up to 39 meters, is planned to begin operation in the next decade and promises new challenges in the development of instruments since the instrument size increases in proportion to the telescope diameter D, and the cost as D 2 or faster. The growing field of astrophotonics (the use of photonic technologies in astronomy) could solve this problem by allowing mass production of fully integrated and robust instruments combining various optical functions, with the potential to reduce the size, complexity and cost of instruments. Astrophotonics allows for a broad range of new optical functions, with applications ranging from sky background filtering, high spatial and spectral resolution imaging and spectroscopy. In this paper, we want to provide astronomers with valuable keys to understand how photonics solutions can be implemented (or not) according to the foreseen applications. The paper introduces first key concepts linked to the characteristics of photonics technologies, placed in the framework of astronomy and spectroscopy. We then describe a series of merit criteria that help us determine the potential of a given micro-spectrograph technology for astronomy applications, and then take an inventory of the recent developments in integrated micro-spectrographs with potential for astronomy. We finally compare their performance, to finally draw a map of typical science requirements and pin the identified integrated technologies on it. We finally emphasize the necessary developments that must support micro-spectrograph in the coming years.

Artist Concept of MAVEN Imaging Ultraviolet Spectrograph at Work

NASA Image and Video Library

2014-11-07

This artist concept depicts the Imaging Ultraviolet Spectrograph IUVS on NASA MAVEN spacecraft scanning the upper atmosphere of Mars. IUVS uses limb scans to map the chemical makeup and vertical structure across Mars upper atmosphere.

High-resolution Observation of Moving Magnetic Features in Active Regions

NASA Astrophysics Data System (ADS)

Li, Qin; Deng, Na; Jing, Ju; Wang, Haimin

2017-08-01

Moving magnetic features (MMFs) are small photospheric magnetic elements that emerge and move outward toward the boundary of moat regions mostly during a sunspot decaying phase, in a serpent wave-like magnetic topology. Studies of MMFs and their classification (e.g., unipolar or bipolar types) strongly rely on the high spatiotemporal-resolution observation of photospheric magnetic field. In this work, we present a detailed observation of a sunspot evolution in NOAA active region (AR) 12565, using exceptionally high resolution Halpha images from the 1.6 New Solar telescope (NST) at Big Bear Solar Observatory (BBSO) and the UV images from the Interface Region Imaging Spectrograph (IRIS). The spectropolarimetric measurements of photospheric magnetic field are obtained from the NST Near InfraRed Imaging Spectropolarimeter (NIRIS) at Fe I 1.56 um line. We investigate the horizontal motion of the classified MMFs and discuss the clustering patterns of the geometry and motion of the MMFs. We estimate the rate of flux generation by appearance of MMFs and the role MMFs play in sunspot decaying phase. We also study the interaction between the MMFs and the existing magnetic field features and its response to Ellerman bombs and IRIS bombs respectively at higher layers.

Prime Focus Spectrograph for the Subaru telescope: massively multiplexed optical and near-infrared fiber spectrograph

NASA Astrophysics Data System (ADS)

Sugai, Hajime; Tamura, Naoyuki; Karoji, Hiroshi; Shimono, Atsushi; Takato, Naruhisa; Kimura, Masahiko; Ohyama, Youichi; Ueda, Akitoshi; Aghazarian, Hrand; de Arruda, Marcio Vital; Barkhouser, Robert H.; Bennett, Charles L.; Bickerton, Steve; Bozier, Alexandre; Braun, David F.; Bui, Khanh; Capocasale, Christopher M.; Carr, Michael A.; Castilho, Bruno; Chang, Yin-Chang; Chen, Hsin-Yo; Chou, Richard C. Y.; Dawson, Olivia R.; Dekany, Richard G.; Ek, Eric M.; Ellis, Richard S.; English, Robin J.; Ferrand, Didier; Ferreira, Décio; Fisher, Charles D.; Golebiowski, Mirek; Gunn, James E.; Hart, Murdock; Heckman, Timothy M.; Ho, Paul T. P.; Hope, Stephen; Hovland, Larry E.; Hsu, Shu-Fu; Hu, Yen-Shan; Huang, Pin Jie; Jaquet, Marc; Karr, Jennifer E.; Kempenaar, Jason G.; King, Matthew E.; le Fèvre, Olivier; Mignant, David Le; Ling, Hung-Hsu; Loomis, Craig; Lupton, Robert H.; Madec, Fabrice; Mao, Peter; Souza Marrara, Lucas; Ménard, Brice; Morantz, Chaz; Murayama, Hitoshi; Murray, Graham J.; Cesar de Oliveira, Antonio; Mendes de Oliveira, Claudia; Souza de Oliveira, Ligia; Orndorff, Joe D.; de Paiva Vilaça, Rodrigo; Partos, Eamon J.; Pascal, Sandrine; Pegot-Ogier, Thomas; Reiley, Daniel J.; Riddle, Reed; Santos, Leandro; dos Santos, Jesulino Bispo; Schwochert, Mark A.; Seiffert, Michael D.; Smee, Stephen A.; Smith, Roger M.; Steinkraus, Ronald E.; Sodré, Laerte; Spergel, David N.; Surace, Christian; Tresse, Laurence; Vidal, Clément; Vives, Sebastien; Wang, Shiang-Yu; Wen, Chih-Yi; Wu, Amy C.; Wyse, Rosie; Yan, Chi-Hung

2015-07-01

The Prime Focus Spectrograph (PFS) is an optical/near-infrared multifiber spectrograph with 2394 science fibers distributed across a 1.3-deg diameter field of view at the Subaru 8.2-m telescope. The wide wavelength coverage from 0.38 μm to 1.26 μm, with a resolving power of 3000, simultaneously strengthens its ability to target three main survey programs: cosmology, galactic archaeology and galaxy/AGN evolution. A medium resolution mode with a resolving power of 5000 for 0.71 μm to 0.89 μm will also be available by simply exchanging dispersers. We highlight some of the technological aspects of the design. To transform the telescope focal ratio, a broad-band coated microlens is glued to each fiber tip. A higher transmission fiber is selected for the longest part of the cable system, optimizing overall throughput; a fiber with low focal ratio degradation is selected for the fiber-positioner and fiber-slit components, minimizing the effects of fiber movements and fiber bending. Fiber positioning will be performed by a positioner consisting of two stages of piezo-electric rotary motors. The positions of these motors are measured by taking an image of artificially back-illuminated fibers with the metrology camera located in the Cassegrain container; the fibers are placed in the proper location by iteratively measuring and then adjusting the positions of the motors. Target light reaches one of the four identical fast-Schmidt spectrograph modules, each with three arms. The PFS project has passed several project-wide design reviews and is now in the construction phase.

Large and small-scale structures in Saturn's rings

NASA Astrophysics Data System (ADS)

Albers, N.; Rehnberg, M. E.; Brown, Z. L.; Sremcevic, M.; Esposito, L. W.

2017-09-01

Observations made by the Cassini spacecraft have revealed both large and small scale structures in Saturn's rings in unprecedented detail. Analysis of high-resolution measurements by the Cassini Ultraviolet Spectrograph (UVIS) High Speed Photometer (HSP) and the Imaging Science Subsystem (ISS) show an abundance of intrinsic small-scale structures (or clumping) seen across the entire ring system. These include self-gravity wakes (50-100m), sub-km structure at the A and B ring edges, and "straw"/"ropy" structures (1-3km).

Solar CIV Vacuum-Ultraviolet Fabry-Perot Interferometers

NASA Technical Reports Server (NTRS)

Gary, G. Allen; West, Edward A.; Rees, David; McKay, Jack A.; Zukic, Maumer; Herman, Peter

2006-01-01

Aims: A tunable, high spectral resolution, high effective finesse, vacuum ultraviolet (VUV) Fabry-Perot interferometer (PPI) is designed for obtaining narrow-passband images, magnetograms, and Dopplergrams of the transition region emission line of CIV (155 nm). Methods: The integral part of the CIV narrow passband filter package (with a 2-10 pm FWHM) consists of a multiple etalon system composed of a tunable interferometer that provides high-spectral resolution and a static low-spectral resolution interferometer that allows a large effective free spectral range. The prefilter for the interferometers is provided by a set of four mirrors with dielectric high-reflective coatings. A tunable interferometer, a VUV piezoelectric-control etalon, has undergone testing using the surrogate F2 eximer laser line at 157 nm for the CIV line. We present the results of the tests with a description of the overall concept for a complete narrow-band CIV spectral filter. The static interferometer of the filter is envisioned as being hudt using a set of fixed MgF2 plates. The four-mirror prefilter is designed to have dielectric multilayer n-stacks employing the design concept used in the Ultraviolet Imager of NASA's Polar Spacecraft. A dual etalon system allows the effective free spectral range to be commensurate with the prefilter profile. With an additional etalon, a triple etalon system would allow a spectrographic resolution of 2 pm. The basic strategy has been to combine the expertise of spaceflight etalon manufacturing with VUV coating technology to build a VUV FPI which combines the best attributes of imagers and spectrographs into a single compact instrument. Results. Spectro-polarimetry observations of the transition region CIV emission can be performed to increase the understanding of the magnetic forces, mass motion, evolution, and energy release within the solar atmosphere at the base of the corona where most of the magnetic field is approximately force-free. The 2D imaging of the full vector magnetic field at the height of maximum magnetic influence (minimum plasma beta) can be accomplished, albeit difficult, by measuring the Zeeman splitting of the CIV resonance pair. Designs of multiple VUV FPIs can be developed for integration into future orbiting solar observatories to obtain rapid cadence, spectral imaging of the transition region.

Earth-orbiting extreme ultraviolet spectroscopic mission: SPRINT-A/EXCEED

NASA Astrophysics Data System (ADS)

Yoshikawa, I.; Tsuchiya, F.; Yamazaki, A.; Yoshioka, K.; Uemizu, K.; Murakami, G.; Kimura, T.; Kagitani, M.; Terada, N.; Kasaba, Y.; Sakanoi, T.; Ishii, H.; Uji, K.

2012-09-01

The EXCEED (Extreme Ultraviolet Spectroscope for Exospheric Dynamics) mission is an Earth-orbiting extreme ultraviolet (EUV) spectroscopic mission and the first in the SPRINT series being developed by ISAS/JAXA. It will be launched in the summer of 2013. EUV spectroscopy is suitable for observing tenuous gases and plasmas around planets in the solar system (e.g., Mercury, Venus, Mars, Jupiter, and Saturn). Advantage of remote sensing observation is to take a direct picture of the plasma dynamics and distinguish between spatial and temporal variability explicitly. One of the primary observation targets is an inner magnetosphere of Jupiter, whose plasma dynamics is dominated by planetary rotation. Previous observations have shown a few percents of the hot electron population in the inner magnetosphere whose temperature is 100 times higher than the background thermal electrons. Though the hot electrons have a significant impact on the energy balance in the inner magnetosphere, their generation process has not yet been elucidated. In the EUV range, a number of emission lines originate from plasmas distributed in Jupiter's inner magnetosphere. The EXCEED spectrograph is designed to have a wavelength range of 55-145 nm with minimum spectral resolution of 0.4 nm, enabling the electron temperature and ion composition in the inner magnetosphere to be determined. Another primary objective is to investigate an unresolved problem concerning the escape of the atmosphere to space. Although there have been some in-situ observations by orbiters, our knowledge is still limited. The EXCEED mission plans to make imaging observations of plasmas around Venus and Mars to determine the amounts of escaping atmosphere. The instrument's field of view (FOV) is so wide that we can get an image from the interaction region between the solar wind and planetary plasmas down to the tail region at one time. This will provide us with information about outward-flowing plasmas, e.g., their composition, rate, and dependence on solar activity. EXCEED has two mission instruments: the EUV spectrograph and a target guide camera that is sensitive to visible light. The EUV spectrograph is designed to have a wavelength range of 55-145 nm with a spectral resolution of 0.4-1.0 nm. The spectrograph slits have a FOV of 400 x 140 arcseconds (maximum). The optics of the instrument consists of a primary mirror with a diameter of 20cm, a laminar type grating, and a 5-stage micro-channel plate assembly with a resistive anode encoder. To achieve high efficiencies, the surfaces of the primary mirror and the grating are coated with CVD-SiC. Because of the large primary mirror and high efficiencies, good temporal resolution and complete spatial coverage for Io plasma torus observation is expected. Based on a feasibility study using the spectral diagnosis method, it is shown that EXCEED can determine the Io plasma torus parameters, such as the electron density, temperatures, hot electron fraction and so on, using an exposure time of 50 minutes. The target guide camera will be used to capture the target and guide the observation area of interest to the slit. Emissions from outside the slit's FOV will be reflected by the front of the slit and guided to the target guide camera. The guide camera's FOV is 240" x 240". The camera will take an image every 3 seconds and the image is sent to a mission data processor (MDP), which calculates the centroid of the image. During an observation, the bus system controls the attitude to keep the centroid position of the target in the guide camera with an accuracy of ±5 arc-seconds. With the help of the target guide camera, we will take spectral images with a long exposure time of 50 minutes and good spatial resolution of 20 arc-seconds.

The BigBOSS spectrograph

NASA Astrophysics Data System (ADS)

Jelinsky, Patrick; Bebek, Chris; Besuner, Robert; Carton, Pierre-Henri; Edelstein, Jerry; Lampton, Michael; Levi, Michael E.; Poppett, Claire; Prieto, Eric; Schlegel, David; Sholl, Michael

2012-09-01

BigBOSS is a proposed ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a 14,000 square degree galaxy and quasi-stellar object redshift survey. It consists of a 5,000- fiber-positioner focal plane feeding the spectrographs. The optical fibers are separated into ten 500 fiber slit heads at the entrance of ten identical spectrographs in a thermally insulated room. Each of the ten spectrographs has a spectral resolution (λ/Δλ) between 1500 and 4000 over a wavelength range from 360 - 980 nm. Each spectrograph uses two dichroic beam splitters to separate the spectrograph into three arms. It uses volume phase holographic (VPH) gratings for high efficiency and compactness. Each arm uses a 4096x4096 15 μm pixel charge coupled device (CCD) for the detector. We describe the requirements and current design of the BigBOSS spectrograph. Design trades (e.g. refractive versus reflective) and manufacturability are also discussed.

Characterization and on-sky demonstration of an integrated photonic spectrograph for astronomy.

PubMed

Cvetojevic, N; Lawrence, J S; Ellis, S C; Bland-Hawthorn, J; Haynes, R; Horton, A

2009-10-12

We present results from the first on-sky demonstration of a prototype astronomical integrated photonic spectrograph (IPS) using the Anglo-Australian Telescope near-infrared imaging spectrometer (IRIS2) at Siding Spring Observatory to observe atmospheric molecular OH emission lines. We have succeeded in detecting upwards of 27 lines, and demonstrated the practicality of the IPS device for astronomy. Furthermore, we present a laboratory characterization of the device, which is a modified version of a commercial arrayed-waveguide grating multiplexer. We measure the spectral resolution full-width-half-maximum to be 0.75 +/- 0.05 nm (giving R = lambda/deltalambda = 2100 +/- 150 at 1500 nm). We find the free spectral range to be 57.4 +/- 0.6 nm and the peak total efficiency to be approximately 65%. Finally, we briefly discuss the future steps required to realize an astronomical instrument based on this technology concept.

Solar physics at the Einstein Tower

NASA Astrophysics Data System (ADS)

Denker, C.; Heibel, C.; Rendtel, J.; Arlt, K.; Balthasar, Juergen H.; Diercke, A.; González Manrique, S. J.; Hofmann, A.; Kuckein, C.; Önel, H.; Senthamizh Pavai, V.; Staude, J.; Verman, M.

2016-11-01

The solar observatory Einstein Tower ({Einsteinturm}) at the Telegrafenberg in Potsdam is both a landmark of modern architecture and an important place for solar physics. Originally built for high-resolution spectroscopy and measuring the gravitational redshift, research shifted over the years to understanding the active Sun and its magnetic field. Nowadays, telescope and spectrographs are used for research and development, i.e., testing instruments and in particular polarization optics for advanced instrumentation deployed at major European and international astronomical and solar telescopes. In addition, the Einstein Tower is used for educating and training of the next generation astrophysicists as well as for education and public outreach activities directed at the general public. This article comments on the observatory's unique architecture and the challenges of maintaining and conserving the building. It describes in detail the characteristics of telescope, spectrographs, and imagers; it portrays some of the research and development activities.

SPECTROSCOPIC OBSERVATIONS OF AN EVOLVING FLARE RIBBON SUBSTRUCTURE SUGGESTING ORIGIN IN CURRENT SHEET WAVES

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

Brannon, S. R.; Longcope, D. W.; Qiu, J.

2015-09-01

We present imaging and spectroscopic observations from the Interface Region Imaging Spectrograph of the evolution of the flare ribbon in the SOL2014-04-18T13:03 M-class flare event, at high spatial resolution and time cadence. These observations reveal small-scale substructure within the ribbon, which manifests as coherent quasi-periodic oscillations in both position and Doppler velocities. We consider various alternative explanations for these oscillations, including modulation of chromospheric evaporation flows. Among these, we find the best support for some form of wave localized to the coronal current sheet, such as a tearing mode or Kelvin–Helmholtz instability.

Commissioning the Robert Stobie Spectrograph on the 11-meter Southern African Large Telescope (SALT)

NASA Astrophysics Data System (ADS)

Hooper, Eric Jon; Nordsieck, K.; Williams, T.; Buckley, D.; SALT Operations Group; UW-Madison RSS Commissioning Group

2012-01-01

The Southern African Large Telescope (SALT) is an 11-meter optical and near-infrared telescope located in South Africa. It is operated by an international consortium led by South Africa and consisting of partners in the U.S., Europe, India, and New Zealand. After some initial telescope image quality problems were fixed, one of the main workhorse instruments called the Robert Stobie Spectrograph began checkout and commissioning in April, 2011. All of the instrument modes have been shown to be operational, and some of them are now in routine use. Shared-risk science observations began in September, 2011, alongside ongoing commissioning of the more unusual modes of this very versatile and complex instrument. The RSS provides numerous capabilities in a compact prime-focus design with an 8 arcminute field of view: • Long-slit spectroscopy. Six gratings provide resolving powers ranging from 800 to 11,000 and wavelength coverage from the blue atmospheric cutoff (320 nm) to around 1000 nm. • Multi-object spectroscopy using laser-cut slit masks. • High speed spectroscopy. By restricting the field of view in a slot mode, spectra can be read out as rapidly as 10 Hz. • Fixed band imaging. In addition to providing help with target acquisition, the RSS imaging mode is a powerful narrow-band imaging system, with a suite of narrow-band filters nearly continuously covering the wavelength range 430 - 900 nm. • Fabry-Perot imaging. The system can operate with either one or two etalons, providing a range in spectral resolving power from 250 to 10,000 over 430- 900 nm. • Polarimetry. All of the modes listed above also support polarimetric modes (linear and circular). Two next-generation instruments are under construction: a high-resolution fiber-fed spectrograph with resolving power reaching 65,000; and a near-infrared sibling of RSS, which will extend the spectral coverage to 1.7 microns.

Characterization of spatial and spectral resolution of a rotating prism chromotomographic hyperspectral imager

NASA Astrophysics Data System (ADS)

Bostick, Randall L.; Perram, Glen P.; Tuttle, Ronald

2009-05-01

The Air Force Institute of Technology (AFIT) has built a rotating prism chromotomographic hyperspectral imager (CTI) with the goal of extending the technology to exploit spatially extended sources with quickly varying (> 10 Hz) phenomenology, such as bomb detonations and muzzle flashes. This technology collects successive frames of 2-D data dispersed at different angles multiplexing spatial and spectral information which can then be used to reconstruct any arbitrary spectral plane(s). In this paper, the design of the AFIT instrument is described and then tested against a spectral target with near point source spatial characteristics to measure spectral and spatial resolution. It will be shown that, in theory, the spectral and spatial resolution in the 3-D spectral image cube is the nearly the same as a simple prism spectrograph with the same design. However, error in the knowledge of the prism linear dispersion at the detector array as a function of wavelength and projection angle will degrade resolution without further corrections. With minimal correction for error and use of a simple shift-and-add reconstruction algorithm, the CTI is able to produce a spatial resolution of about 2 mm in the object plane (234 μrad IFOV) and is limited by chromatic aberration. A spectral resolution of less than 1nm at shorter wavelengths is shown, limited primarily by prism dispersion.

PEPSI, the High-Resolution Optical-IR Spectrograph for the LBT

NASA Astrophysics Data System (ADS)

Andersen, Michael; Strassmeier, Klaus; Hoffman, Axel; Woche, Manfred; Spano, Paolo

PEPSI is a high resolution fibre feed optical-IR polarimetric echelle spectrograph for the Large Binocular Telescope (LBT). PEPSI utilizes the two 8.4m LBT apertures to simultaneously record four polarization states at a resolution of 120.000. The extension of the coverage towards the IR is mainly motivated by the larger Zeeman splitting of IR lines, which would allow to study weaker/fainter magnetic structures on stars. The two optical arms, which also have an integral light mode with R up to 300.000, are under construction, while the IR arm is being designed.

Astronomical near-infrared echelle gratings

NASA Astrophysics Data System (ADS)

Hinkle, Kenneth H.; Joyce, Richard R.; Liang, Ming

2014-07-01

High-resolution near-infrared echelle spectrographs require coarse rulings in order to match the free spectral range to the detector size. Standard near-IR detector arrays typically are 2 K x 2 K or 4 K x 4 K. Detectors of this size combined with resolutions in the range 30000 to 100000 require grating groove spacings in the range 5 to 20 lines/mm. Moderately high blaze angles are desirable to reduce instrument size. Echelle gratings with these characteristics have potential wide application in both ambient temperature and cryogenic astronomical echelle spectrographs. We discuss optical designs for spectrographs employing immersed and reflective echelle gratings. The optical designs set constraints on grating characteristics. We report on market choices for obtaining these gratings and review our experiments with custom diamond turned rulings.

PUMA: the first results of a nebular spectrograph for the study of the kinematics of interstellar medium

NASA Astrophysics Data System (ADS)

Langarica, Rosalia; Bernal, Abel; Rosado, Margarita; Cobos Duenas, Francisco J.; Garfias, Fernando; Gutierrez, Leonel; Le Coarer, Etienne; Tejada, Carlos; Tinoco, Silvio J.

1998-07-01

The kinematics of the interstellar medium may be studied by means of a scanning Fabry-Perot interferometer (SFPI). This allows the coverage of a wider field of view with higher spatial and spectral resolution than when a high-dispersion classical spectrograph is used. The system called PUMA consists of a focal reducer and a SFPI installed in the 2.1 m telescope of the San Pedro Martir National Astronomical Observatory (SPM), Mexico, in its f/7.5 configuration. It covers a field of view of 10 arcmin providing direct images as well as interferograms which are focused on a 1024 X 1024 Tektronix CCD, covering a wide spectral range. It is considered the integration of other optical elements for further developments. The optomechanical system and the developed software allow exact, remote positioning of all movable parts and control the FPI scanning and data acquisition. The parallelism of the interferometer plates is automatically achieved by a custom method. The PUMA provides spectral resolutions of 0.414 Angstrom and a free spectral range of 19.8 Angstrom. Results of high quality that compete with those obtained by similar systems in bigger telescopes, are presented.

Dust Temperatures and Opacities in the Central Parsec of the Galactic Center Modeled from Analysis of Multi-Wavelength Mid-Infrared Images

NASA Technical Reports Server (NTRS)

Varosi, F.; Gezari, D.; Dwek, E.; Telesco, C.

2016-01-01

We have analyzed multi-wavelength mid-infrared images of the central parsec of the Galactic Center using a two-temperature line-of-sight (LOS) radiative transfer model at each pixel of the images, giving maps of temperatures, luminosities and opacities of the hot, warm, cold (dark)dust components. The data consists of images at nine wavelengths in the mid-infrared (N-band and Q-band) from the Thermal Region Camera and Spectrograph (T-ReCS) instrument operating at the Gemini South Observatory. The results of the LOS modeling indicate that the extinction optical depth is quite large and varies substantially over the FOV. The high-resolution images of the central parsec of the Galactic center region were obtained with T-ReCS at Gemini South in January 2004. These images provide nearly diffraction-limited resolution (approx. 0.5) of the central parsec. The T-ReCS images were taken with nine filters (3.8, 4.7, 7.7, 8.7, 9.7, 10.3, 12.3, 18.3 and 24.5m), over a field-of-view (FOV) of 20 x 20 arcsec.

VizieR Online Data Catalog: Abundances in dwarfs, subgiants, and giants (da Silva+, 2015)

NASA Astrophysics Data System (ADS)

da Silva, R.; Milone, A. C.; Rocha-Pinto, H. J.

2015-05-01

Photospheric parameters mass, age, and the abundances of C, N, O, Na, Mg, Si, Ca, Ti, V, Mn, Fe, Ni, Cu, and Ba for a sample of FGK dwarfs, subgiants, and giants are derived. We used spectra of high-resolution (R~42,000) and high S/N (>150 on average) available in the ELODIE online database (Moultaka et al., 2004PASP..116..693M). These are spectra collected with the ELODIE high-resolution spectrograph (Baranne et al. 1996) of the Haute Provence Observatory (France). Only spectra with individual S/N>20 and with an image type classified as "object fibre only" (OBJO) were used. (7 data files).

STELLA: 10 years of robotic observations on Tenerife

NASA Astrophysics Data System (ADS)

Weber, Michael; Granzer, Thomas; Strassmeier, Klaus G.

2016-07-01

STELLA is a robotic observatory on Tenerife housing two 1.2m robotic telescopes. One telescope is fibre-feeding a high-resolution (R=55,000) échelle spectrograph (SES), while the other telescope is equipped with a visible wide- field (FOV=22' x 22') imaging instrument (WiFSIP). Robotic observations started mid 2006, and the primary scientific driver is monitoring of stellar-activity related phenomena. The STELLA Control System (SCS) software package was originally tailored to the STELLA roll-off style building and high-resolution spectroscopy, but was extended over the years to support the wide-field imager, an off-axis guider for the imager, separate acquisition telescopes, classical domes, and targets-of-opportunity. The SCS allows for unattended, off-line operation of the observatory, targets can be uploaded at any time and are selected based on merit-functions in real-time (dispatch scheduling). We report on the current status of the observatory and the current capabilities of the SCS.

J0815+4729: A Chemically Primitive Dwarf Star in the Galactic Halo Observed with Gran Telescopio Canarias

NASA Astrophysics Data System (ADS)

Aguado, David S.; González Hernández, Jonay I.; Allende Prieto, Carlos; Rebolo, Rafael

2018-01-01

We report the discovery of the carbon-rich hyper metal-poor unevolved star J0815+4729. This dwarf star was selected from SDSS/BOSS as a metal-poor candidate and follow-up spectroscopic observations at medium resolution were obtained with the Intermediate dispersion Spectrograph and Imaging System (ISIS) at William Herschel Telescope and the Optical System for Imaging and low-intermediate-Resolution Integrated Spectroscopy (OSIRIS) at Gran Telescopio de Canarias. We use the FERRE code to derive the main stellar parameters, {T}{eff}=6215+/- 82 K, and {log}g=4.7+/- 0.5, an upper limit to the metallicity of [Fe/H] ≤ ‑5.8, and a carbon abundance of [C/Fe] ≥ +5.0, while [α /{Fe}]=0.4 is assumed. The metallicity upper limit is based on the Ca II K line, which at the resolving power of the OSIRIS spectrograph cannot be resolved from possible interstellar calcium. The star could be the most iron-poor unevolved star known and also be among the ones with the largest overabundances of carbon. High-resolution spectroscopy of J0815+4729 will certainly help to derive other important elemental abundances, possibly providing new fundamental constraints on the early stages of the universe, the formation of the first stars, and the properties of the first supernovae. Based on observations made with the Gran Telescopio Canarias (GTC), installed in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias, on the island of La Palma. Program ID GTC90-15B and the Discretionary Director Time GTC03-16ADDT and also based on observations made with the William Herschel Telescope (WHT).

High-resolution setup for measuring wavelength sensitivity of photoyellowing of translucent materials

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

Vaskuri, Anna, E-mail: anna.vaskuri@aalto.fi; Kärhä, Petri; Heikkilä, Anu

2015-10-15

Polystyrene and many other materials turn yellow when exposed to ultraviolet (UV) radiation. All photodegradation mechanisms including photoyellowing are functions of the exposure wavelength, which can be described with an action spectrum. In this work, a new high-resolution transmittance measurement setup based on lasers has been developed for measuring color changes, such as the photoyellowing of translucent materials aged with a spectrograph. The measurement setup includes 14 power-stabilized laser lines between 325 nm and 933 nm wavelengths, of which one at a time is directed on to the aged sample. The power transmitted through the sample is measured with amore » silicon detector utilizing an integrating sphere. The sample is mounted on a high-resolution XY translation stage. Measurement at various locations aged with different wavelengths of exposure radiation gives the transmittance data required for acquiring the action spectrum. The combination of a UV spectrograph and the new high-resolution transmittance measurement setup enables a novel method for studying the UV-induced ageing of translucent materials with a spectral resolution of 3–8 nm, limited by the adjustable spectral bandwidth range of the spectrograph. These achievements form a significant improvement over earlier methods.« less

VizieR Online Data Catalog: Very metal-poor stars in the Milky Way's halo (Carollo+, 2014)

NASA Astrophysics Data System (ADS)

Carollo, D.; Freeman, K.; Beers, T. C.; Placco, V. M.; Tumlinson, J.; Martell, S. L.

2017-07-01

The Aoki et al. (2013, J/AJ/145/13) sample comprises 137 stars observed at high spectral resolution (R~30000), in the course of four observing runs between 2008 March and October, using the High Dispersion Spectrograph (Noguchi et al. 2002PASJ...54..855N) at the Subaru Telescope. We also include 190 stars from the Yong et al. (2013, J/ApJ/762/26) sample - the 38 stars from their "program sample," and 152 stars in their literature compilation. High-resolution spectra (22000

VizieR Online Data Catalog: weak G-band stars abundances (Palacios+, 2016)

NASA Astrophysics Data System (ADS)

Palacios, A.; Jasniewicz, G.; Masseron, T.; Thevenin, F.; Itam-Pasquet, J.; Parthasarathy, M.

2016-05-01

Seventeen southern wGb stars were observed at La Silla, ESO Chile, with the high-efficiency Fiber-fed Extended Range Optical Spectrograph FEROS spectrograph mounted on the 2.2m telescope. FEROS is a bench-mounted, thermally controlled, prism-cross-dispersed echelle spectrograph, providing, in a single spectrogram spread over 39 orders, almost complete spectral coverage from ~350 to ~920nm at a resolution of 48000. The FEROS observations were carried out during an observing run between May 10 and 13, 2012. All these spectra were flat-fielded and calibrated by means of ThArNe exposures using standard processing tools available at ESO. In addition, two northern wGb stars, HD 18474 and HD 166208, were observed in service mode at the Observatoire du Pic du Midi, France, with the NARVAL spectrograph mounted on the Bernard Lyot 2.0m telescope. The NARVAL instrument consists of a bench-mounted cross-dispersed echelle spectrograph, fibre-fed from a Cassegrain-mounted polarimeter unit. It was used in its non-polarimetric mode; it provided almost complete spectral coverage from ~375 to ~1050nm at a resolution of 75000 in a single spectrogram spread over 40 orders. (6 data files).

Spectral multiplexing using stacked volume-phase holographic gratings - I

NASA Astrophysics Data System (ADS)

Zanutta, A.; Landoni, M.; Riva, M.; Bianco, A.

2017-08-01

Many focal-reducer spectrographs, currently available at state-of-the-art telescopes facilities, would benefit from a simple refurbishing that could increase both the resolution and spectral range in order to cope with the progressively challenging scientific requirements, but, in order to make this update appealing, it should minimize the changes in the existing structure of the instrument. In the past, many authors proposed solutions based on stacking subsequently layers of dispersive elements and recording multiple spectra in one shot (multiplexing). Although this idea is promising, it brings several drawbacks and complexities that prevent the straightforward integration of such a device in a spectrograph. Fortunately, nowadays, the situation has changed dramatically, thanks to the successful experience achieved through photopolymeric holographic films, used to fabricate common volume-phase holographic gratings (VPHGs). Thanks to the various advantages made available by these materials in this context, we propose an innovative solution to design a stacked multiplexed VPHG that is able to secure efficiently different spectra in a single shot. This allows us to increase resolution and spectral range enabling astronomers to greatly economize their awarded time at the telescope. In this paper, we demonstrate the applicability of our solution, both in terms of expected performance and feasibility, supposing the upgrade of the Gran Telescopio CANARIAS (GTC) Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy (OSIRIS).

Automatic parquet block sorting using real-time spectral classification

NASA Astrophysics Data System (ADS)

Astrom, Anders; Astrand, Erik; Johansson, Magnus

1999-03-01

This paper presents a real-time spectral classification system based on the PGP spectrograph and a smart image sensor. The PGP is a spectrograph which extracts the spectral information from a scene and projects the information on an image sensor, which is a method often referred to as Imaging Spectroscopy. The classification is based on linear models and categorizes a number of pixels along a line. Previous systems adopting this method have used standard sensors, which often resulted in poor performance. The new system, however, is based on a patented near-sensor classification method, which exploits analogue features on the smart image sensor. The method reduces the enormous amount of data to be processed at an early stage, thus making true real-time spectral classification possible. The system has been evaluated on hardwood parquet boards showing very good results. The color defects considered in the experiments were blue stain, white sapwood, yellow decay and red decay. In addition to these four defect classes, a reference class was used to indicate correct surface color. The system calculates a statistical measure for each parquet block, giving the pixel defect percentage. The patented method makes it possible to run at very high speeds with a high spectral discrimination ability. Using a powerful illuminator, the system can run with a line frequency exceeding 2000 line/s. This opens up the possibility to maintain high production speed and still measure with good resolution.

The X-ray spectrographic telescope. [for solar corona observation

NASA Technical Reports Server (NTRS)

Vaiana, G. S.; Krieger, A. S.; Petrasso, R.; Silk, J. K.; Timothy, A. F.

1974-01-01

The S-054 X-ray telescope, which operated successfully throughout the eight-month Skylab mission, is a grazing incidence instrument with a spatial resolution of the order of 2 arc sec on axis. The total wavelength range observed by the instrument is 2 to 60 A. Crude spectral resolution within this range is achieved by means of a series of six X-ray filter materials. A spectrographic mode of operation, employing an objective grating, is used to obtain spectra of flare events and selected coronal features.

Emirates Mars Ultraviolet Spectrometer (EMUS) Overview from the Emirates Mars Mission

NASA Astrophysics Data System (ADS)

Almatroushi, Hessa; Lootah, Fatma; Holsclaw, Greg; Deighan, Justin; Chaffin, Michael; Lillis, Robert; Fillingim, Matthew; England, Scott; AlMheiri, Suhail; Reed, Heather

2017-04-01

The Emirates Mars Ultraviolet Spectrometer (EMUS) instrument is one of three science instruments to be carried on board the Emirate Mars Mission (EMM), the "Hope Probe". EMM is a United Arab Emirates' (UAE) mission to Mars launching in 2020 to explore the dynamics in the Martian atmosphere globally, while sampling on both diurnal and seasonal timescales. The EMUS instrument is a far-ultraviolet imaging spectrograph that measures emissions in the spectral range 100-170 nm. Using spacecraft motion, it will build up two-dimensional far-ultraviolet images of the Martian disk and near-space environment at several important wavelengths: Lyman beta atomic hydrogen emission (102.6 nm), Lyman alpha atomic hydrogen emission (121.6 nm), atomic oxygen emission (130.4 nm and 135.6 nm), and carbon monoxide fourth positive group band emission (140 nm-170 nm). Radiances at these wavelengths will be used to derive the column abundance of atomic oxygen, and carbon monoxide in the Martian thermosphere, and the density of atomic oxygen and atomic hydrogen in the Martian exosphere both with spatial and sub-seasonal variability. EMUS consists of a single telescope mirror feeding a Rowland circle imaging spectrograph capable of selectable spectral resolution (1.3 nm, 1.8 nm, or 5 nm) with a photon-counting and locating detector (provided by the Space Sciences Laboratory at the University of California, Berkeley). The EMUS spatial resolution of less than 300km on the disk is sufficient to characterize spatial variability in the Martian thermosphere (100-200 km altitude) and exosphere (>200 km altitude). The instrument is jointly developed by the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder and Mohammed Bin Rashid Space Centre (MBRSC) in Dubai, UAE

The Stellar-IRIS Connection: Four Years of FUV Measurements of Alpha Centauri by HST/STIS

NASA Astrophysics Data System (ADS)

Ayres, Thomas R.

2014-06-01

Since 2010 January, shortly after the miraculous repair of Hubble's Space Telescope Imaging Spectrograph (STIS) by SM4, the two sun-like stars of Alpha Centauri ("A" [G2V] and "B" [K1V]) have been recorded on a semi-annual basis utilizing STIS's far-ultraviolet (115-170 nm) medium resolution mode (about 8 km/s FWHM resolving power), jointly with an X-ray imaging study of AB by the Chandra Observatory. Both efforts are intended to assess the long-term behavior of high-energy (multimillion K) coronal, and subcoronal, processes on the two relatively low-activity solar-age dwarfs. In fact, the near-solar-twin Alpha Cen A has been mired in a coronal lull since 2005, originally recognized by XMM-Newton, and only recently has begun to climb out of the extended X-ray minimum. Meanwhile, the lower mass, lower luminosity, but coronally more active secondary has displayed a clear 8-year X-ray cycle, extending from the mid-1990's ROSAT era. The current study focuses on properties of the "transition zone" lines ( 100,000 K) of the Alpha Centauri stars, namely the bulk redshifts exhibited by the Si IV, C IV, and N V doublets; the multi-component nature of the hot-line profiles; behavior of the Fe XII 124 nm coronal forbidden line; and variability of the FUV fluxes relative to the higher-energy X-ray time series. These stellar measurements, with their high precision in wavelength and flux, complement the detailed high-spatial and high-temporal resolution spectral mapping of the solar corona and lower atmosphere being carried out by NASA's Interface Region Imaging Spectrograph (IRIS). [This work supported by GO grants 12758, 13060, and 13465 from Space Telescope Science Institute.

Goodman High Throughput Spectrograph | SOAR

Science.gov Websites

SPARTAN Near-IR Camera Ohio State Infrared Imager/Spectrograph (OSIRIS) - NO LONGER AVAILABLE SOAR 320-850 nm wavelength range. The paper describing the instrument is Clemens et al. (2004) Applying for IRAF. Publishing results based on Goodman data?: ADS link to 2004 SPIE Goodman Spectrograph paper

Stratospheric Observatory for Infrared Astronomy (SOFIA)

NASA Astrophysics Data System (ADS)

Becklin, E. E.; Tielens, A. G. G. M.; Gehrz, R. D.; Callis, H. H. S.

2007-09-01

The joint U.S. and German SOFIA project to develop and operate a 2.5-meter infrared airborne telescope in a Boeing 747-SP is now in its final stages of development. Flying in the stratosphere, SOFIA allows observations throughout the infrared and submillimeter region with an average transmission of >= 80%. The SOFIA instrument complement includes broadband imagers, moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. These instruments will enable SOFIA to make unique contributions to a broad array of science topics. First science flights will begin in 2009, and the observatory is expected to operate for more than 20 years. The sensitivity, characteristics, science instrument complement, and examples of first light science are discussed.

Apollo 16 far-ultraviolet imagery and spectra of the Large Magellanic Cloud

NASA Technical Reports Server (NTRS)

Page, T.; Carruthers, G. R.

1976-01-01

The Large Magellanic Cloud was observed by the far ultraviolet camera spectrograph from the lunar surface during the Apollo 16 mission 22 April 1972. Images were obtained with about 3 arc min resolution, in the 1,050 to 1,600 and 1,250 to 1,600 A wavelength ranges, of nearly the entire LMC. Spectra were also obtained in the 1,050 to 1,600 and 900 to 1,600 A ranges along a strip 1/4 deg wide (determined by the instrument's grid collimator) passing across the LMC. The images and spectra have been scanned with a PDS microdensitometer, and isodensity contour plots have been prepared using the Univac 1108 computer.

The interaction of the outflow with the molecular disk in the Active Galactic Nucleus of NGC 6951

NASA Astrophysics Data System (ADS)

May, D.; Steiner, J. E.; Ricci, T. V.; Menezes, R. B.; Andrade, I. S.

2015-02-01

Context: we present a study of the central 200 pc of NGC 6951, in the optical and NIR, taken with the Gemini North Telescope integral field spectrographs, with resolution of ~ 0''.1 Methods: we used a set of image processing techniques, as the filtering of high spatial and spectral frequencies, Richardson-Lucy deconvolution and PCA Tomography (Steiner et al. 2009) to map the distribution and kinematics of the emission lines. Results: we found a thick molecular disk, with the ionization cone highly misaligned.

The Performance and Scientific Rationale for an Infrared Imaging Fourier Transform Spectrograph on a Large Space Telescope

DTIC Science & Technology

1998-06-22

micromirrors . Thus, an IFTS will produce a rich scientific legacy with tremendous potential for serendipity. Table 1 details the capabilities of an IFTS...maintain modulation efficiency. Curves are plotted for resolutions , 105, and 1064R 5 k/dk 5 10 assuming an 8 m diameter primary aperture and a beam splitter...passbands centered at 1.1, 1.3, 1.7, 2.3, and 3.6 mm. Colors are plotted from ; a triangle is plotted at every interval of unit redshift. These curves

First light results from the Hermes spectrograph at the AAT

NASA Astrophysics Data System (ADS)

Sheinis, Andrew; Barden, Sam; Birchall, Michael; Carollo, Daniela; Bland-Hawthorn, Joss; Brzeski, Jurek; Case, Scott; Cannon, Russell; Churilov, Vladimir; Couch, Warrick; Dean, Robert; De Silva, Gayandhi; D'Orazi, Valentina; Farrell, Tony; Fiegert, Kristin; Freeman, Kenneth; Frost, Gabriella; Gers, Luke; Goodwin, Michael; Gray, Doug; Heald, Ron; Heijmans, Jeroen; Jones, Damien; Keller, Stephan; Klauser, Urs; Kondrat, Yuriy; Lawrence, Jon; Lee, Steve; Mali, Slavko; Martell, Sarah; Mathews, Darren; Mayfield, Don; Miziarski, Stan; Muller, Rolf; Pai, Naveen; Patterson, Robert; Penny, Ed; Orr, David; Shortridge, Keith; Simpson, Jeffrey; Smedley, Scott; Smith, Greg; Stafford, Darren; Staszak, Nicholas; Vuong, Minh; Waller, Lewis; Wylie de Boer, Elizabeth; Xavier, Pascal; Zheng, Jessica; Zhelem, Ross; Zucker, Daniel

2014-07-01

The High Efficiency and Resolution Multi Element Spectrograph, HERMES is an facility-class optical spectrograph for the AAT. It is designed primarily for Galactic Archeology [21], the first major attempt to create a detailed understanding of galaxy formation and evolution by studying the history of our own galaxy, the Milky Way. The goal of the GALAH survey is to reconstruct the mass assembly history of the of the Milky Way, through a detailed spatially tagged abundance study of one million stars. The spectrograph is based at the Anglo Australian Telescope (AAT) and is fed by the existing 2dF robotic fiber positioning system. The spectrograph uses VPH-gratings to achieve a spectral resolving power of 28,000 in standard mode and also provides a high-resolution mode ranging between 40,000 to 50,000 using a slit mask. The GALAH survey requires a SNR greater than 100 for a star brightness of V=14. The total spectral coverage of the four channels is about 100nm between 370 and 1000nm for up to 392 simultaneous targets within the 2 degree field of view. Hermes has been commissioned over 3 runs, during bright time in October, November and December 2013, in parallel with the beginning of the GALAH Pilot survey starting in November 2013. In this paper we present the first-light results from the commissioning run and the beginning of the GALAH Survey, including performance results such as throughput and resolution, as well as instrument reliability. We compare the abundance calculations from the pilot survey to those in the literature.

Efficient photonic reformatting of celestial light for diffraction-limited spectroscopy

NASA Astrophysics Data System (ADS)

MacLachlan, D. G.; Harris, R. J.; Gris-Sánchez, I.; Morris, T. J.; Choudhury, D.; Gendron, E.; Basden, A. G.; Spaleniak, I.; Arriola, A.; Birks, T. A.; Allington-Smith, J. R.; Thomson, R. R.

2017-02-01

The spectral resolution of a dispersive astronomical spectrograph is limited by the trade-off between throughput and the width of the entrance slit. Photonic guided wave transitions have been proposed as a route to bypass this trade-off, by enabling the efficient reformatting of incoherent seeing-limited light collected by the telescope into a linear array of single modes: a pseudo-slit which is highly multimode in one axis but diffraction-limited in the dispersion axis of the spectrograph. It is anticipated that the size of a single-object spectrograph fed with light in this manner would be essentially independent of the telescope aperture size. A further anticipated benefit is that such spectrographs would be free of `modal noise', a phenomenon that occurs in high-resolution multimode fibre-fed spectrographs due to the coherent nature of the telescope point spread function (PSF). We seek to address these aspects by integrating a multicore fibre photonic lantern with an ultrafast laser inscribed three-dimensional waveguide interconnect to spatially reformat the modes within the PSF into a diffraction-limited pseudo-slit. Using the CANARY adaptive optics (AO) demonstrator on the William Herschel Telescope, and 1530 ± 80 nm stellar light, the device exhibits a transmission of 47-53 per cent depending upon the mode of AO correction applied. We also show the advantage of using AO to couple light into such a device by sampling only the core of the CANARY PSF. This result underscores the possibility that a fully optimized guided-wave device can be used with AO to provide efficient spectroscopy at high spectral resolution.

The Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS)

NASA Technical Reports Server (NTRS)

Oegerle, William (Technical Monitor); Rabin, D.; Davila, J.; Thomas, R. J.; Engler, C.; Irish, S.; Keski-Kuha, R.; Novello, J.; Nowak, M.; Payne, L.;

SOFIA science instruments: commissioning, upgrades and future opportunities

NASA Astrophysics Data System (ADS)

Smith, Erin C.; Miles, John W.; Helton, L. Andrew; Sankrit, Ravi; Andersson, B. G.; Becklin, Eric E.; De Buizer, James M.; Dowell, C. D.; Dunham, Edward W.; Güsten, Rolf; Harper, Doyal A.; Herter, Terry L.; Keller, Luke D.; Klein, Randolf; Krabbe, Alfred; Logsdon, Sarah; Marcum, Pamela M.; McLean, Ian S.; Reach, William T.; Richter, Matthew J.; Roellig, Thomas L.; Sandell, Göran; Savage, Maureen L.; Temi, Pasquale; Vacca, William D.; Vaillancourt, John E.; Van Cleve, Jeffrey E.; Young, Erick T.

2014-07-01

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is the world's largest airborne observatory, featuring a 2.5 meter effective aperture telescope housed in the aft section of a Boeing 747SP aircraft. SOFIA's current instrument suite includes: FORCAST (Faint Object InfraRed CAmera for the SOFIA Telescope), a 5-40 μm dual band imager/grism spectrometer developed at Cornell University; HIPO (High-speed Imaging Photometer for Occultations), a 0.3-1.1μm imager built by Lowell Observatory; GREAT (German Receiver for Astronomy at Terahertz Frequencies), a multichannel heterodyne spectrometer from 60-240 μm, developed by a consortium led by the Max Planck Institute for Radio Astronomy; FLITECAM (First Light Infrared Test Experiment CAMera), a 1-5 μm wide-field imager/grism spectrometer developed at UCLA; FIFI-LS (Far-Infrared Field-Imaging Line Spectrometer), a 42-200 μm IFU grating spectrograph completed by University Stuttgart; and EXES (Echelon-Cross-Echelle Spectrograph), a 5-28 μm highresolution spectrometer designed at the University of Texas and being completed by UC Davis and NASA Ames Research Center. HAWC+ (High-resolution Airborne Wideband Camera) is a 50-240 μm imager that was originally developed at the University of Chicago as a first-generation instrument (HAWC), and is being upgraded at JPL to add polarimetry and new detectors developed at Goddard Space Flight Center (GSFC). SOFIA will continually update its instrument suite with new instrumentation, technology demonstration experiments and upgrades to the existing instrument suite. This paper details the current instrument capabilities and status, as well as the plans for future instrumentation.

Tunable laser techniques for improving the precision of observational astronomy

NASA Astrophysics Data System (ADS)

Cramer, Claire E.; Brown, Steven W.; Lykke, Keith R.; Woodward, John T.; Bailey, Stephen; Schlegel, David J.; Bolton, Adam S.; Brownstein, Joel; Doherty, Peter E.; Stubbs, Christopher W.; Vaz, Amali; Szentgyorgyi, Andrew

2012-09-01

Improving the precision of observational astronomy requires not only new telescopes and instrumentation, but also advances in observing protocols, calibrations and data analysis. The Laser Applications Group at the National Institute of Standards and Technology in Gaithersburg, Maryland has been applying advances in detector metrology and tunable laser calibrations to problems in astronomy since 2007. Using similar measurement techniques, we have addressed a number of seemingly disparate issues: precision flux calibration for broad-band imaging, precision wavelength calibration for high-resolution spectroscopy, and precision PSF mapping for fiber spectrographs of any resolution. In each case, we rely on robust, commercially-available laboratory technology that is readily adapted to use at an observatory. In this paper, we give an overview of these techniques.

Shuttle-based measurements: GLO ultraviolet earthlimb view

NASA Astrophysics Data System (ADS)

Gardner, James A.; Murad, Edmond; Viereck, Rodney A.; Knecht, David J.; Pike, Charles P.; Broadfoot, A. Lyle

1996-11-01

The GLO experiment is an on-going shuttle-based spectrograph/imager project that has returned ultraviolet (100 - 400 nm) limb views. High spectral (0.35 nm FWHM) and temporal (4 s) resolution spectra include simultaneous altitude profiles (in the range of 80 - 400 km tangent height with 10 km resolution) of dayglow and nightglow features. Measured emissions include the NO gamma, N2 Vegard-Kaplan and second positive, N2+ first negative, and O2 Herzberg I band systems and both atomic and cation lines of N, O, and Mg. This data represents a low solar activity benchmark for future observations. We report on the status of the GLO project, which included three space flights in 1995, and present spectral data on important ultraviolet band systems.

15x optical zoom and extreme optical image stabilisation: diffraction limited integral field spectroscopy with the Oxford SWIFT spectrograph

NASA Astrophysics Data System (ADS)

Tecza, Matthias; Thatte, Niranjan; Clarke, Fraser; Lynn, James; Freeman, David; Roberts, Jennifer; Dekany, Richard

2012-09-01

When commissioned in November 2008 at the Palomar 200 inch Hale Telescope, the Oxford SWIFT I and z band integral field spectrograph, fed by the adaptive optics system PALAO, provided a wide (3×) range of spatial resolutions: three plate scales of 235 mas, 160 mas, and 80 mas per spaxel over a contiguous field-of-view of 89×44 pixels. Depending on observing conditions and guide star brightness we can choose a seeing limited scale of 235 mas per spaxel, or 160 mas and 80 mas per spaxel for very bright guide star AO with substantial increase of enclosed energy. Over the last two years PALAO was upgraded to PALM-3000: an extreme, high-order adaptive optics system with two deformable mirrors with more than 3000 actuators, promising diffraction limited performance in SWIFT's wavelength range. In order to take advantage of this increased spatial resolution we upgraded SWIFT with new pre-optics allowing us to spatially Nyquist sample the diffraction limited PALM-3000 point spread function with 16 mas resolution, reducing the spaxel scale by another factor of 5×. We designed, manufactured, integrated and tested the new pre-optics in the first half of 2011 and commissioned it in December 2011. Here we present the opto-mechanical design and assembly of the new scale changing optics, as well as laboratory and on-sky commissioning results. In optimal observing conditions we achieve substantial Strehl ratios, delivering the near diffraction limited spatial resolution in the I and z bands.

VizieR Online Data Catalog: Kinematic analysis of M7-L8 dwarfs (Faherty+, 2016)

NASA Astrophysics Data System (ADS)

Faherty, J. K.; Riedel, A. R.; Cruz, K. L.; Gagne, J.; Filippazzo, J. C.; Lambrides, E.; Fica, H.; Weinberger, A.; Thorstensen, J. R.; Tinney, C. G.; Baldassare, V.; Lemonier, E.; Rice, E. L.

2017-08-01

The sample of 152 M7-L8 ultra-cool dwarfs comprising our sample (see table 1) were placed on follow-up programs --either imaging (parallax, proper motion), spectroscopy (radial velocity), or both-- to determine kinematic membership in a nearby moving group. For Northern Hemisphere astrometry targets, we obtained I-band images with the MDM Observatory 2.4m Hiltner telescope on Kitt Peak, Arizona. We also observed 16 of the most southern targets with the Carnegie Astrometric Planet Search Camera (CAPSCam) on the 100 inch du Pont telescope and 5 with the FourStar imaging camera on the Magellan Baade Telescope. Table 2 gives the pertinent astrometric information; Table 3 lists our measured parallaxes and proper motions. New proper-motion measurements are listed in Table 5. See also section 3.1. We used the 6.5m Baade Magellan telescope and the FIRE spectrograph to obtain near-infrared spectra of 36 sources. Observations were made over seven runs between 2013 July and 2014 September. All observations (resolution R~6000) cover the full 0.8-2.5um band with a spatial resolution of 0.18"/pixel. We used the 3m NASA IRTF to obtain low-resolution near-infrared spectroscopy for 10 targets. All of the observations were aligned to the parallactic angle to obtain R~120 spectral data over the wavelength range of 0.7-2.5um. We used the Triple Spectrograph (TSpec) at the 5m Hale Telescope at Palomar Observatory to obtain near-infrared spectra of two targets. TSpec covers simultaneously the range from 1.0 to 2.45um and achieves a resolution of ~2500. Exposure times for each source and the number of images acquired are listed in Table 6; see also section 3.2. Multiple observations of 17 sources were taken in high-resolution mode on Keck II on 2008 September 14-16, using the NIRSPEC-5 filter to obtain H-band spectra in Order 49 (1.545-1.570um ). Observations of 18 sources were taken during semesters 2007B and 2009B using the H6420 filter of the Phoenix instrument (previously on Gemini South) to select H-band spectra in Order 36 (1.551-1.558um). Red-side spectra were taken with MIKE on the Magellan II (Clay) telescope on 2006 July 4, 2006 November 1 and 2 for 17 targets. Observational data for each source are listed in Table 7; see also section 3.3. (10 data files).

Handheld spatial frequency domain spectrographic imager for depth-sensitive, quantitative spectroscopy of skin tissue

NASA Astrophysics Data System (ADS)

Saager, Rolf B.; Dang, An N.; Huang, Samantha S.; Kelly, Kristen M.; Durkin, Anthony J.

2017-02-01

Here we present a handheld, implementation of Spatial Frequency Domain Spectroscopy (SFDS) that employs line imaging. The new instrument can measure 1088 spatial locations that span a 3 cm line as opposed to our benchtop system that only collects a single 1 mm diameter spot. This imager, however, retains the spectral resolution ( 1 nm) and range (450 to 1000 nm) of our benchtop system. The device also has tremendously improved mobility and portability, allowing for greater ease of use in clinical setting. A smaller size also enables access to different tissue locations, which increases the flexibility of the device. The design of this portable system not only enables SFDS to be used in clinical settings, but also enables visualization of properties of layered tissues such as skin.

An echelle spectrograph for middle ultraviolet solar spectroscopy from rockets.

PubMed

Tousey, R; Purcell, J D; Garrett, D L

1967-03-01

An echelle grating spectrograph is ideal for use in a rocket when high resolution is required becaus itoccupies a minimum of space. The instrument described covers the range 4000-2000 A with a resolution of 0.03 A. It was designed to fit into the solar biaxial pointing-control section of an Aerobee-150 rocket. The characteristics of the spectrograph are illustrated with laboratory spectra of iron and carbon are sources and with solar spectra obtained during rocket flights in 1961 and 1964. Problems encountered in analyzing the spectra are discussed. The most difficult design problem was the elimination of stray light when used with the sun. Of the several methods investigated, the most effective was a predispersing system in the form of a zero-dispersion double monochromator. This was made compact by folding the beam four times.

The Stratospheric Observatory for Infrared Astronomy (sofia)

NASA Astrophysics Data System (ADS)

Gehrz, R. D.; Becklin, E. E.

2011-06-01

The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (SOFIA) is a 2.5- meter infrared airborne telescope in a Boeing 747-SP that began science flights in 2010. Flying in the stratosphere at altitudes as high as 45,000 feet, SOFIA can conduct photometric, spectroscopic, and imaging observations at wavelengths from 0.3 microns to 1.6 millimeters with an average transmission of greater than 80 percent. SOFIA is staged out of the NASA Dryden Flight Research Center aircraft operations facility at Palmdale, CA and the SOFIA Science Mission Operations Center (SSMOC) is located at NASA Ames Research Center, Moffett Field, CA. SOFIA's first-generation instrument complement includes high speed photometers, broadband imagers, moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. About 100 eight to ten hour flights per year are expected by 2014, and the observatory will operate until the mid 2030's. We will review the status of the SOFIA facility, its initial complement of science instruments, and the opportunities for advanced instrumentation.

Temperature-dependent refractive index measurements of L-BBH2 glass for the Subaru CHARIS integral field spectrograph

NASA Astrophysics Data System (ADS)

Leviton, Douglas B.; Miller, Kevin H.; Quijada, Manuel A.; Groff, Tyler D.

2015-09-01

Using the Cryogenic High Accuracy Refraction Measuring System (CHARMS) at NASA's Goddard Space Flight Center, we have made the first cryogenic measurements of absolute refractive index for Ohara L-BBH2 glass to enable the design of a prism for the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) at the Subaru telescope. L-BBH2 is employed in CHARIS's prism design for improving the spectrograph's dispersion uniformity. Index measurements were made at temperatures from 110 to 305 K at wavelengths from 0.46 to 3.16 μm. We report absolute refractive index (n), dispersion (dn/dλ), and thermo-optic coefficient (dn/dT) for this material along with estimated single measurement uncertainties as a function of wavelength and temperature. We provide temperature-dependent Sellmeier coefficients based on our data to allow accurate interpolation of index to other wavelengths and temperatures within applicable ranges. This paper also speaks of the challenges in measuring index for a material which is not available in sufficient thickness to fabricate a typical prism for measurement in CHARMS, the tailoring of the index prism design that allowed these index measurements to be made, and the remarkable results obtained from that prism for this practical infrared material.

Temperature-Dependent Refractive Index Measurements of L-BBH2 Glass for the Subaru CHARIS Integral Field Spectrograph

NASA Technical Reports Server (NTRS)

Leviton, Douglas B.; Miller, Kevin H.; Quijada, Manuel A.; Groff, Tyler D.

2015-01-01

Using the Cryogenic High Accuracy Refraction Measuring System (CHARMS) at NASA's Goddard Space Flight Center, we have made the first cryogenic measurements of absolute refractive index for Ohara L-BBH2 glass to enable the design of a prism for the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) at the Subaru telescope. L-BBH2 is employed in CHARIS's prism design for improving the spectrograph's dispersion uniformity. Index measurements were made at temperatures from 110 to 305 K at wavelengths from 0.46 to 3.16 micron. We report absolute refractive index (n), dispersion (dn/d(lambda), and thermo-optic coefficient (dn/dT) for this material along with estimated single measurement uncertainties as a function of wavelength and temperature. We provide temperature-dependent Sellmeier coefficients based on our data to allow accurate interpolation of index to other wavelengths and temperatures within applicable ranges. This paper also speaks of the challenges in measuring index for a material which is not available in sufficient thickness to fabricate a typical prism for measurement in CHARMS, the tailoring of the index prism design that allowed these index measurements to be made, and the remarkable results obtained from that prism for this practical infrared material.

Using CeSiC for UV spectrographs for the WSO/UV

NASA Astrophysics Data System (ADS)

Reutlinger, A.; Gál, C.; Brandt, C.; Haberler, P.; Zuknik, K.-H.; Sedlmaier, T.; Shustov, B.; Sachkov, M.; Moisheev, A.; Kappelmann, N.; Barnstedt, J.; Werner, K.

2017-11-01

The World Space Observatory Ultraviolet (WSO/UV) is a multi-national project lead by the Russian Federal Space Agency (Roscosmos) with the objective of high performance observations in the ultraviolet range. The 1.7 m WSO/UV telescope feeds UV spectrometers and UV imagers. The UV spectrometers comprise two high resolution Echelle spectrographs for the 100 - 170 nm and 170 - 300 nm wavelength range and a long slit spectrograph for the 100 - 300 nm band. All three spectrometers represent individual instruments that are assembled and aligned separately. In order to save mass while maintaining high stiffness, the instruments are combined to a monoblock. Cesic has been selected to reduce CTE related distortions of the instruments. In contrast to aluminium, the stable structure of Cesic is significantly less sensitive to thermal gradients. No further mechanism for focus correction with high functional, technical and operational complexity and dedicated System costs are necessary. Using Cesic also relaxes the thermal control requirements of +/-5°C, which represents a considerable cost driver for the S/C design. The WUVS instrument is currently studied in the context of a phase B2 study by Kayser-Threde GmbH including a Structural Thermal Model (STM) for verification of thermal and mechanical loads, stability due to thermal distortions and Cesic manufacturing feasibility.

Vacuum ultraviolet instrumentation for solar irradiance and thermospheric airglow

NASA Technical Reports Server (NTRS)

Woods, Thomas N.; Rottman, Gary J.; Bailey, Scott M.; Solomon, Stanley C.

1993-01-01

A NASA sounding rocket experiment was developed to study the solar extreme ultraviolet (EUV) spectral irradiance and its effect on the upper atmosphere. Both the solar flux and the terrestrial molecular nitrogen via the Lyman-Birge-Hopfield bands in the far ultraviolet (FUV) were measured remotely from a sounding rocket on October 27, 1992. The rocket experiment also includes EUV instruments from Boston University (Supriya Chakrabarti), but only the National Center for Atmospheric Research (NCAR)/University of Colorado (CU) four solar instruments and one airglow instrument are discussed here. The primary solar EUV instrument is a 1/4 meter Rowland circle EUV spectrograph which has flown on three rockets since 1988 measuring the solar spectral irradiance from 30 to 110 nm with 0.2 nm resolution. Another solar irradiance instrument is an array of six silicon XUV photodiodes, each having different metallic filters coated directly on the photodiodes. This photodiode system provides a spectral coverage from 0.1 to 80 nm with about 15 nm resolution. The other solar irradiance instrument is a silicon avalanche photodiode coupled with pulse height analyzer electronics. This avalanche photodiode package measures the XUV photon energy providing a solar spectrum from 50 to 12,400 eV (25 to 0.1 nm) with an energy resolution of about 50 eV. The fourth solar instrument is an XUV imager that images the sun at 17.5 nm with a spatial resolution of 20 arc-seconds. The airglow spectrograph measures the terrestrial FUV airglow emissions along the horizon from 125 to 160 nm with 0.2 nm spectral resolution. The photon-counting CODACON detectors are used for three of these instruments and consist of coded arrays of anodes behind microchannel plates. The one-dimensional and two-dimensional CODACON detectors were developed at CU by Dr. George Lawrence. The pre-flight and post-flight photometric calibrations were performed at our calibration laboratory and at the Synchrotron Ultraviolet Radiation Facility (SURF) at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland.

The design and performance of high resolution échelle spectrographs in astronomy

NASA Astrophysics Data System (ADS)

Barnes, Stuart

The design and performance of several high resolution spectrographs for use in astronomy will be described. After a basic outline of the required theory, the design and performance of HERCULES will be presented. HERCULES is an R2 spectrograph fibre-fed from the MJUO 1-m telescope. The échelle grating has 31.6 grooves/mm and it uses a BK7 prism with a 50° apex angle in double-pass for cross-dispersion. A folded Schmidt camera is used for imaging. With a detector having an area 50 x 50 mm, and pixels less than 25 µm, HERCULES is capable of resolving powers of 40,000 to 80,000 and wavelength coverage from 380 to 880 nm. The total throughput (from the fibre entrance to the CCD) is expected to be nearly 20% (in 1" seeing). Measured efficiencies are only slightly less than this. HERCULES is also shown to be capable of excellent radial velocity precision with no apparent difference between long-term and short-term stability. Several significant upgrade options are also described. As part of the evolution of the design of a high resolution spectrograph for SALT, several instruments were developed for 10-metre class telescopes. Early designs, based in part on the successful HERCULES design, did not meet the requirements of a number of potential users, due in particular to the limited ability to inter-leave object and sky orders. This resulted in the design of SALT HRS R2 which uses a mosaic of two 308 x 413 mm R2 échelle gratings with 87 grooves/mm. Cross-dispersion is achieved with a pair of large 40° apex angle BK7 prisms used in double-pass. The échelle grating accepts a 365-mm collimated beam. The camera is a catadioptric system having a 1.2-m primary mirror and three lenses made of BK7 each around 850 mm in diameter. Complete unvignetted (except by the CCD obstruction) wavelength coverage from 370nm to 890nm is possible on a mosaic of three 2k by 4k CCDS with 15 µm pixels. A maximum resolving power of R ≈ 80,000 is possible. For immunity to atmospheric pressure and temperature changes the entire spectrograph is designed to be housed inside either a helium atmosphere or a light vacuum. The spectrograph chamber is nearly seven metres long. An alternative to the R2 SALT HRS is also described. This instrument is an R4 dual beam spectrograph based on a white pupil layout. The design is based on suggestions by B. Delabre and follows closely this authors SOAR HRS instrument. SALT HRS R4 uses volume-phased holographic gratings for cross-dispersion and a 836 x 204 mm échelle grating with 41.6 grooves/mm. The grating will be replicated from two smaller gratings onto a single Zerodur blank. The spectrograph is split into blue and red arms by a dichroic located near the white pupil relay intermediate focus. Wavelengths from 370 nm to 890 nm are covered by two fixed format blue and red dedicated dioptric cameras. The detectors will be a single 2k by 4k CCD with 15 µm pixels for the blue camera and a 4k by 4k CCD with 15 µm pixels for the red. The size of the cameras is reduced significantly by white pupil demagnification from an initial 200-mm diameter collimated beam incident on the échelle grating to around 100 mm (in undispersed light) on the VPH gratings. The final SALT HRS R4 instrument is also designed to be immersed in a vacuum vessel which is considerably smaller than that proposed for the R2 spectrograph. SALT HRS R4 is currently being developed in detail and will be presented for a critical design review in 2005 April.

High efficiency spectrographs for the EUV and soft X-rays

NASA Technical Reports Server (NTRS)

Cash, W.

1983-01-01

The use of grazing incidence optics and reflection grating designs is shown to be a method that improves the performance of spectrographs at wavelengths shorter than 1200 A. Emphasis is laid on spectroscopic designs for X ray and EUV astronomy, with sample designs for an objective reflection grating spectrograph (ORGS) and an echelle spectrograph for wavelengths longer than 100 A. Conical diffraction allows operations at grazing incidence in the echelle spectrograph. In ORGS, the extreme distance of X ray objects aids in collimating the source radiation, which encounters conical diffraction within the instrument, proceeds parallel to the optical axis, and arrives at the detector. A series of gratings is used to achieve the effect. A grazing echelle is employed for EUV observations, and offers a resolution of 20,000 over a 300 A bandpass.

Lithium abundance in a sample of solar-like stars

NASA Astrophysics Data System (ADS)

López-Valdivia, R.; Hernández-Águila, J. B.; Bertone, E.; Chávez, M.; Cruz-Saenz de Miera, F.; Amazo-Gómez, E. M.

2015-08-01

We report on the determination of the lithium abundance [A(Li)] of 52 solar-like stars. For 41 objects the A(Li) here presented corresponds to the first measurement. We have measured the equivalent widths of the 6708 Å lithium feature in high-resolution spectroscopic images (R ˜ 80 000), obtained at the Observatorio Astrofísico Guillermo Haro (Sonora, Mexico), as part of the first scientific observations of the revitalized Lunar and Planetary Laboratory (LPL) Echelle Spectrograph, now known as the Cananea High-resolution Spectrograph (CanHiS). Lithium abundances were derived with the Fortran code MOOG, using as fundamental input a set of atmospheric parameters recently obtained by our group. With the help of an additional small sample with previous A(Li) determinations, we demonstrate that our lithium abundances are in agreement, to within uncertainties, with other works. Two target objects stand out from the rest of the sample. The star BD+47 3218 (Teff = 6050 ± 52 K, A(Li) = 1.86 ± 0.07 dex) lies inside the so-called lithium desert in the A(Li)-Teff plane. The other object, BD+28 4515, has an A(Li) = 3.05 ± 0.07 dex, which is the highest of our sample and compatible with the expected abundances of relatively young stars.

“MODAL NOISE” IN SINGLE-MODE FIBERS: A CAUTIONARY NOTE FOR HIGH PRECISION RADIAL VELOCITY INSTRUMENTS

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

Halverson, Samuel; Roy, Arpita; Mahadevan, Suvrath

2015-12-01

Exploring the use of single-mode fibers (SMFs) in high precision Doppler spectrometers has become increasingly attractive since the advent of diffraction-limited adaptive optics systems on large-aperture telescopes. Spectrometers fed with these fibers can be made significantly smaller than typical “seeing-limited” instruments, greatly reducing cost and overall complexity. Importantly, classical mode interference and speckle issues associated with multi-mode fibers, also known as “modal noise,” are mitigated when using SMFs, which also provide perfect radial and azimuthal image scrambling. However, SMFs do support multiple polarization modes, an issue that is generally ignored for larger-core fibers given the large number of propagation modes.more » Since diffraction gratings used in most high resolution astronomical instruments have dispersive properties that are sensitive to incident polarization changes, any birefringence variations in the fiber can cause variations in the efficiency profile, degrading illumination stability. Here we present a cautionary note outlining how the polarization properties of SMFs can affect the radial velocity (RV) measurement precision of high resolution spectrographs. This work is immediately relevant to the rapidly expanding field of diffraction-limited, extreme precision RV spectrographs that are currently being designed and built by a number of groups.« less

Development of the MAMA Detectors for the Hubble Space Telescope Imaging Spectrograph

NASA Technical Reports Server (NTRS)

Timothy, J. Gethyn

1997-01-01

The development of the Multi-Anode Microchannel Array (MAMA) detector systems started in the early 1970's in order to produce multi-element detector arrays for use in spectrographs for solar studies from the Skylab-B mission. Development of the MAMA detectors for spectrographs on the Hubble Space Telescope (HST) began in the late 1970's, and reached its culmination with the successful installation of the Space Telescope Imaging Spectrograph (STIS) on the second HST servicing mission (STS-82 launched 11 February 1997). Under NASA Contract NAS5-29389 from December 1986 through June 1994 we supported the development of the MAMA detectors for STIS, including complementary sounding rocket and ground-based research programs. This final report describes the results of the MAMA detector development program for STIS.

Observations of hydrogen-rich supernovae in the first days after explosion and new instruments to study them

NASA Astrophysics Data System (ADS)

Rubin, Adam; PTF

2018-01-01

I will discuss our results studying light curves of hydrogen-rich supernovae during the first few days after explosion. The first days of emission encode important information about the physical system, and it is possible to relate the early-time light curve to the radius of the progenitor star by using shock-cooling models. I will show the first systematic application of these models to data from the Palomar Transient Factory (PTF). We found that R-band data alone at PTF cadence cannot constrain the radius but can constrain the energy per unit mass of the explosion, uncovering new correlations with other supernova observables. We constrained the radii for events with multi-wavelength observations, and for two events observed with the Kepler mission at 30 min cadence. I will discuss improved observing strategies to obtain more constraining results in the future. Some tensions have arisen between our results and the expected radii from identified progenitors of hydrogen-rich supernovae. The resolution of these tensions may be related to the effect of circumstellar material on the light curves, motivating future systematic spectroscopic sequencing of these events. To this end, we have designed a new medium resolution UV-VIS spectrograph. The Multi-Imaging Transient Spectrograph (MITS) is the R~4500 UV-VIS arm of the Son Of X-Shooter (SOXS) spectrograph proposed for ESO’s 3.6 m New Technology Telescope. Our design divides the spectrum into several sub-bands, allowing optimization for each narrow part of the spectrum. We estimate a 50-100% improvement in throughput relative to a classical 4-C echelle design. Our design has passed a preliminary design review and is expected on the telescope in early 2021.

James Webb Space Telescope (JWST) and Star Formation

NASA Technical Reports Server (NTRS)

Greene, Thomas P.

2010-01-01

The 6.5-m aperture James Webb Space Telescope (JWST) will be a powerful tool for studying and advancing numerous areas of astrophysics. Its Fine Guidance Sensor, Near-Infrared Camera, Near-Infrared Spectrograph, and Mid-Infrared Instrument will be capable of making very sensitive, high angular resolution imaging and spectroscopic observations spanning 0.7 - 28 ?m wavelength. These capabilities are very well suited for probing the conditions of star formation in the distant and local Universe. Indeed, JWST has been designed to detect first light objects as well as to study the fine details of jets, disks, chemistry, envelopes, and the central cores of nearby protostars. We will be able to use its cameras, coronagraphs, and spectrographs (including multi-object and integral field capabilities) to study many aspects of star forming regions throughout the galaxy, the Local Group, and more distant regions. I will describe the basic JWST scientific capabilities and illustrate a few ways how they can be applied to star formation issues and conditions with a focus on Galactic regions.

Stellar spectral classification of previously unclassified stars GSC 4461-698 and GSC 4466-870

NASA Astrophysics Data System (ADS)

Grau, Darren Moser

Stellar spectral classification is one of the first efforts undertaken to begin defining the physical characteristics of stars. However, many stars lack even this basic information, which is the foundation for later research to constrain stellar effective temperatures, masses, radial velocities, the number of stars in the system, and age. This research obtained visible-λ stellar spectra via the testing and commissioning of a Santa Barbara Instruments Group (SBIG) Self-Guiding Spectrograph (SGS) at the UND Observatory. Utilizing a 16-inch-aperture telescope on Internet Observatory #3, the SGS obtained spectra of GSC 4461-698 and GSC 4466-870 in the low-resolution mode using an 18-µm wide slit with dispersion of 4.3 Å/pixel, resolution of 8 Å, and a spectral range from 3800-7500 Å. Observational protocols include automatic bias/dark frame subtraction for each stellar spectrum obtained. This was followed by spectral averaging to obtain a combined spectrum for each star observed. Image calibration and spectral averaging was performed using the software programs, Maxim DL, Image J, Microsoft Excel, and Winmk. A wavelength calibration process was used to obtain spectra of an Hg/Ne source that allowed the conversion of spectrograph channels into wavelengths. Stellar emission and absorption lines, such as those for hydrogen (H) and helium (He), were identified, extracted, and rectified. Each average spectrum was compared to the MK stellar spectral standards to determine an initial spectral classification for each star. The hope is that successful completion of this project will allow long-term stellar spectral observations to begin at the UND Observatory.

Retrieval of stratospheric ozone and nitrogen dioxide profiles from Odin Optical Spectrograph and Infrared Imager System (OSIRIS) limb-scattered sunlight measurements

NASA Astrophysics Data System (ADS)

Haley, Craig Stuart

2009-12-01

Key to understanding and predicting the effects of global environmental problems such as ozone depletion and global warming is a detailed understanding of the atmospheric processes, both dynamical and chemical. Essential to this understanding are accurate global data sets of atmospheric constituents with adequate temporal and spatial (vertical and horizontal) resolutions. For this purpose the Canadian satellite instrument OSIRIS (Optical Spectrograph and Infrared Imager System) was launched on the Odin satellite in 2001. OSIRIS is primarily designed to measure minor stratospheric constituents, including ozone (O3) and nitrogen dioxide (NO2), employing the novel limb-scattered sunlight technique, which can provide both good vertical resolution and near global coverage. This dissertation presents a method to retrieve stratospheric O 3 and NO2 from the OSIRIS limb-scatter observations. The retrieval method incorporates an a posteriori optimal estimator combined with an intermediate spectral analysis, specifically differential optical absorption spectroscopy (DOAS). A detailed description of the retrieval method is presented along with the results of a thorough error analysis and a geophysical validation exercise. It is shown that OSIRIS limb-scatter observations successfully produce accurate stratospheric O3 and NO2 number density profiles throughout the stratosphere, clearly demonstrating the strength of the limb-scatter technique. The OSIRIS observations provide an extremely useful data set that is of particular importance for studies of the chemistry of the middle atmosphere. The long OSIRIS record of stratospheric ozone and nitrogen dioxide may also prove useful for investigating variability and trends.

The Keck Cosmic Web Imager (KCWI): A Powerful New Integral Field Spectrograph for the Keck Observatory

NASA Astrophysics Data System (ADS)

Morrissey, Patrick; KCWI Team

2013-01-01

The Keck Cosmic Web Imager (KCWI) is a new facility instrument being developed for the W. M. Keck Observatory and funded for construction by the Telescope System Instrumentation Program (TSIP) of the National Science Foundation (NSF). KCWI is a bench-mounted spectrograph for the Keck II right Nasmyth focal station, providing integral field spectroscopy over a seeing-limited field up to 20"x33" in extent. Selectable Volume Phase Holographic (VPH) gratings provide high efficiency and spectral resolution in the range of 1000 to 20000. The dual-beam design of KCWI passed a Preliminary Design Review in summer 2011. The detailed design of the KCWI blue channel (350 to 700 nm) is now nearly complete, with the red channel (530 to 1050 nm) planned for a phased implementation contingent upon additional funding. KCWI builds on the experience of the Caltech team in implementing the Cosmic Web Imager (CWI), in operation since 2009 at Palomar Observatory. KCWI adds considerable flexibility to the CWI design, and will take full advantage of the excellent seeing and dark sky above Mauna Kea with a selectable nod-and-shuffle observing mode. The KCWI team is lead by Caltech (project management, design and implementation) in partnership with the University of California at Santa Cruz (camera optical and mechanical design) and the W. M. Keck Observatory (program oversight and observatory interfaces).

OBSERVATION AND ANALYSIS OF BALLISTIC DOWNFLOWS IN AN M-CLASS FLARE WITH THE INTERFACE REGION IMAGING SPECTROGRAPH

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

Brannon, Sean R.

Despite significant advances in instrumentation, there remain no studies that analyze observations of on-disk flare loop plasma flows covering the entire evolution from chromospheric evaporation, through plasma cooling, to draining downflows. We present results from an imaging and spectroscopic observation from the Interface Region Imaging Spectrograph ( IRIS ) of the SOL2015–03–12T11:50:00 M-class flare, at high spatial resolution and time cadence. Our analysis of this event reveals initial plasma evaporation at flare temperatures indicated by 100–200 km s{sup −1} blueshifts in the Fe xxi line. We subsequently observe plasma cooling into chromospheric lines (Si iv and O iv) with ∼11more » minute delay, followed by loop draining at ∼40 km s{sup −1} as indicated by a “C”-shaped redshift structure and significant (∼60 km s{sup −1}) non-thermal broadening. We use density-sensitive lines to calculate a plasma density for the flare loops, and estimate a theoretical cooling time approximately equal to the observed delay. Finally, we use a simple elliptical free-fall draining model to construct synthetic spectra, and perform what we believe to be the first direct comparison of such synthetic spectra to observations of draining downflows in flare loops.« less

UNDERCOVER EUV SOLAR JETS OBSERVED BY THE INTERFACE REGION IMAGING SPECTROGRAPH

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

Chen, N.-H.; Innes, D. E.

It is well-known that extreme ultraviolet (EUV) emission emitted at the solar surface is absorbed by overlying cool plasma. Especially in active regions, dark lanes in EUV images suggest that much of the surface activity is obscured. Simultaneous observations from the Interface Region Imaging Spectrograph, consisting of UV spectra and slit-jaw images (SJI), give vital information with sub-arcsecond spatial resolution on the dynamics of jets not seen in EUV images. We studied a series of small jets from recently formed bipole pairs beside the trailing spot of active region 11991, which occurred on 2014 March 5 from 15:02:21 UT tomore » 17:04:07 UT. Collimated outflows with bright roots were present in SJI 1400 Å (transition region) and 2796 Å (upper chromosphere) that were mostly not seen in Atmospheric Imaging Assembly (AIA) 304 Å (transition region) and AIA 171 Å (lower corona) images. The Si iv spectra show a strong blue wing enhancement, but no red wing, in the line profiles of the ejecta for all recurrent jets, indicating outward flows without twists. We see two types of Mg ii line profiles produced by the jets spires: reversed and non-reversed. Mg ii lines remain optically thick, but turn optically thin in the highly Doppler shifted wings. The energy flux contained in each recurrent jet is estimated using a velocity differential emission measure technique that measures the emitting power of the plasma as a function of the line-of-sight velocity. We found that all the recurrent jets release similar energy (10{sup 8} erg cm{sup −2} s{sup −1}) toward the corona and the downward component is less than 3%.« less

Undercover EUV Solar Jets Observed by the Interface Region Imaging Spectrograph

NASA Astrophysics Data System (ADS)

Chen, N.-H.; Innes, D. E.

2016-12-01

It is well-known that extreme ultraviolet (EUV) emission emitted at the solar surface is absorbed by overlying cool plasma. Especially in active regions, dark lanes in EUV images suggest that much of the surface activity is obscured. Simultaneous observations from the Interface Region Imaging Spectrograph, consisting of UV spectra and slit-jaw images (SJI), give vital information with sub-arcsecond spatial resolution on the dynamics of jets not seen in EUV images. We studied a series of small jets from recently formed bipole pairs beside the trailing spot of active region 11991, which occurred on 2014 March 5 from 15:02:21 UT to 17:04:07 UT. Collimated outflows with bright roots were present in SJI 1400 Å (transition region) and 2796 Å (upper chromosphere) that were mostly not seen in Atmospheric Imaging Assembly (AIA) 304 Å (transition region) and AIA 171 Å (lower corona) images. The Si IV spectra show a strong blue wing enhancement, but no red wing, in the line profiles of the ejecta for all recurrent jets, indicating outward flows without twists. We see two types of Mg II line profiles produced by the jets spires: reversed and non-reversed. Mg II lines remain optically thick, but turn optically thin in the highly Doppler shifted wings. The energy flux contained in each recurrent jet is estimated using a velocity differential emission measure technique that measures the emitting power of the plasma as a function of the line-of-sight velocity. We found that all the recurrent jets release similar energy (108 erg cm-2 s-1) toward the corona and the downward component is less than 3%.

Design and Construction of VUES: The Vilnius University Echelle Spectrograph

NASA Astrophysics Data System (ADS)

Jurgenson, Colby; Fischer, Debra; McCracken, Tyler; Sawyer, David; Giguere, Matt; Szymkowiak, Andrew; Santoro, Fernando; Muller, Gary

2016-03-01

In February 2014, the Yale Exoplanet Laboratory was commissioned to design, build, and deliver a high resolution (R=60,000) spectrograph for the 1.65m telescope at the Molėtai Astronomical Observatory. The observatory is operated by the Institute of Theoretical Physics and Astronomy at Vilnius University. The Vilnius University Echelle Spectrograph (VUES) is a white-pupil design that is fed via an octagonal fiber from the telescope and has an operational bandpass from 400nm to 880nm. VUES incorporates a novel modular optomechanical design that allows for quick assembly and alignment on commercial optical tables. This approach allowed the spectrograph to be assembled and commissioned at Yale using lab optical tables and then reassembled at the observatory on a different optical table with excellent repeatability. The assembly and alignment process for the spectrograph was reduced to a few days, allowing the spectrograph to be completely disassembled for shipment to Lithuania, and then installed at the observatory during a 10-day period in June of 2015.

Observing Exoplanets with High-dispersion Coronagraphy. II. Demonstration of an Active Single-mode Fiber Injection Unit

NASA Astrophysics Data System (ADS)

Mawet, D.; Ruane, G.; Xuan, W.; Echeverri, D.; Klimovich, N.; Randolph, M.; Fucik, J.; Wallace, J. K.; Wang, J.; Vasisht, G.; Dekany, R.; Mennesson, B.; Choquet, E.; Delorme, J.-R.; Serabyn, E.

2017-04-01

High-dispersion coronagraphy (HDC) optimally combines high-contrast imaging techniques such as adaptive optics/wavefront control plus coronagraphy to high spectral resolution spectroscopy. HDC is a critical pathway toward fully characterizing exoplanet atmospheres across a broad range of masses from giant gaseous planets down to Earth-like planets. In addition to determining the molecular composition of exoplanet atmospheres, HDC also enables Doppler mapping of atmosphere inhomogeneities (temperature, clouds, wind), as well as precise measurements of exoplanet rotational velocities. Here, we demonstrate an innovative concept for injecting the directly imaged planet light into a single-mode fiber, linking a high-contrast adaptively corrected coronagraph to a high-resolution spectrograph (diffraction-limited or not). Our laboratory demonstration includes three key milestones: close-to-theoretical injection efficiency, accurate pointing and tracking, and on-fiber coherent modulation and speckle nulling of spurious starlight signal coupling into the fiber. Using the extreme modal selectivity of single-mode fibers, we also demonstrated speckle suppression gains that outperform conventional image-based speckle nulling by at least two orders of magnitude.

Opto-mechanical design of a new cross dispersion unit for the CRIRES+ high resolution spectrograph for the VLT

NASA Astrophysics Data System (ADS)

Lizon, Jean Louis; Klein, Barbara; Oliva, Ernesto; Löwinger, Tom; Anglada Escude, Guillem; Baade, Dietrich; Bristow, Paul; Dorn, Reinhold J.; Follert, Roman; Grunhut, Jason; Hatzes, Artie; Heiter, Ulrike; Ives, Derek; Jung, Yves; Kerber, Florian; Lockhart, Matt; Marquart, Thomas; Origlia, Livia; Pasquini, Luca; Paufique, Jerome; Piskunov, N.; Pozna, Eszter; Reiners, Ansgar; Smette, Alain; Smoker, Jonathan; Seemann, Ulf; Stempels, Eric; Valenti, Elena

2014-07-01

CRIRES is one of the few IR (0.92-5.2 μm) high-resolution spectrographs in operation at the VLT since 2006. Despite good performance it suffers a limitation that significantly hampers its ability: a small spectral coverage per exposure. The CRIRES upgrade (CRIRES+) proposes to transform CRIRES into a cross-dispersed spectrograph while maintaining the high resolution (100000) and increasing the wavelength coverage by a factor 10 compared to the current capabilities. A major part of the upgrade is the exchange of the actual cryogenic pre-disperser module by a new cross disperser unit. In addition to a completely new optical design, a number of important changes are required on key components and functions like the slit unit and detectors units. We will outline the design of these new units fitting inside a predefined and restricted space. The mechanical design of the new functions including a description and analysis will be presented. Finally we will present the strategy for the implementation of the changes.

Spectroscopic observations with the Stratospheric Observatory for Infrared Astronomy (SOFIA)

NASA Astrophysics Data System (ADS)

Becklin, E. E.; Tielens, A. G. G. M.; Callis, H. H. S.

The joint US and German SOFIA project to develop and operate a 2.5-meter infrared airborne telescope in a Boeing 747-SP is now in its final stages of development. Flying in the stratosphere, SOFIA allows observations through the infrared and submillimeter region, with an average transmission of greater than 80%. SOFIA is characterized by a wide instrument complement ranging from broadband imagers, through moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, to high-resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. This broad range in instruments will enable SOFIA to make unique contributions to a broad array of science topics. First science flights will begin in 2009 and the observatory is expected to operate for over 20 years. The sensitivity, characteristics, science instrument complement, and examples of first light spectroscopic science are discussed.

Stratospheric Observatory for Infrared Astronomy (sofia)

NASA Astrophysics Data System (ADS)

Becklin, E. E.; Tielens, A. G. G. M.; Callis, H. H. S.

The joint U.S. and German SOFIA project to develop and operate a 2.5-meter infrared airborne telescope in a Boeing 747-SP is now in its final stages of development. Flying in the stratosphere, SOFIA allows observations through the infrared and submillimeter region, with an average transmission of ≳ 80%. SOFIA is characterized by a wide instrument complement ranging from broadband imagers, through moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, to high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. This broad range in instruments will enable SOFIA to make unique contributions to a broad array of science topics. First science flights will begin in 2009 and the observatory is expected to operate for over 20 years. The sensitivity, characteristics, science instrument complement, and examples of first light science are discussed.

Stratospheric Observatory for Infrared Astronomy (SOFIA)

NASA Astrophysics Data System (ADS)

Becklin, E. E.; Gehrz, R. D.

2009-08-01

The joint U.S. and German SOFIA project to develop and operate a 2.5-meter infrared airborne telescope in a Boeing 747-SP is in its final stages of development. Flying in the stratosphere, SOFIA allows observations throughout the infrared and submillimeter region, with an average transmission of greater than 80%. SOFIA's first generation instrument complement includes high-speed photometers, broadband imagers, moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km/s resolution. These instruments will enable SOFIA to make unique contributions to a broad array of science topics. First science flights will begin in 2010, and the observatory is expected to operate for more than 20 years. The sensitivity, characteristics, science instrument complement, future instrument opportunities and examples of first light science will be discussed.

On-sky calibration performance of a monolithic Michelson interferometer filtered source

NASA Astrophysics Data System (ADS)

Ge, Jian; Ma, Bo; Powell, Scott; Varosi, Frank; Schofield, Sidney; Grieves, Nolan; Liu, Jian

2014-07-01

In the new era of searching for Earth-like planets, new generation radial velocity (RV) high resolution spectrographs requires ~0.1 m/s Doppler calibration accuracy in the visible band and a similar calibration precision in the near infrared. The patented stable monolithic Michelson interferometer filtered source called the Sine source emerges as a very promising calibration device. This Sine source has the potential of covering the practical working wavelengths (~0.38- 2.5 μm) for Doppler measurements with high resolution optical and near infrared high resolution spectrographs at the ground-based telescopes. The single frame calibration precision can reach < 0.1 m/s for the state of the art spectrographs, and it can be easily designed to match the intrinsic sensitivities of future Doppler instruments. The Sine source also has the great practical advantages in compact (portable) size and low cost. Here we report early results from on-sky calibration of a Sine source measured with two state-of-the-art TOU optical high resolution spectrograph (R=100,000, 0.38-0.9 microns) and FIRST near infrared spectrograph (R=50,000, 0.8-1.8 microns) at a 2 meter robotic telescope at Fairborn Observatory in Arizona. The results with the TOU spectrograph monitoring over seven days show that the Sine source has produced ~3 times better calibration precision than the ThAr calibration (RMS = 2.7m/s vs. 7.4m/s) at 0.49-0.62 microns where calibration data have been processed by our preliminary data pipeline and ~1.4 times better than the iodine absorption spectra (RMS=3.6 m/s) at the same wavelength region. As both ThAr and Iodine have reached sub m/s calibration accuracy with existing Doppler instruments (such as HARPS and HIRES), it is likely that the sine source would provide similar improvement once a better data pipeline and an upgraded version of a Sine source are developed. It is totally possible to reach ~0.1 m/s in the optical wavelength region. In addition, this Sine source offers potential very accurate calibration at 0.7-0.9 μm where ThAr lines are totally dominated by strong and saturated Argon lines and the ThAr calibration data are nearly useless. The early measurements with the FIRST near infrared spectrograph show that this Sine source produces very homogenous fringe modulations over 0.8-1.8 μm which can potentially provide better precision than the UrNe lamp for instrument drift measurements.

The LST scientific instruments

NASA Technical Reports Server (NTRS)

Levin, G. M.

1975-01-01

Seven scientific instruments are presently being studied for use with the Large Space Telescope (LST). These instruments are the F/24 Field Camera, the F/48-F/96 Planetary Camera, the High Resolution Spectrograph, the Faint Object Spectrograph, the Infrared Photometer, and the Astrometer. These instruments are being designed as facility instruments to be replaceable during the life of the Observatory.

Optomechanical design concept for the Giant Magellan Telescope Multi-object Astronomical and Cosmological Spectrograph (GMACS)

NASA Astrophysics Data System (ADS)

Prochaska, Travis; Sauseda, Marcus; Beck, James; Schmidt, Luke; Cook, Erika; DePoy, Darren L.; Marshall, Jennifer L.; Ribeiro, Rafael; Taylor, Keith; Jones, Damien; Froning, Cynthia; Pak, Soojong; Mendes de Oliveira, Claudia; Papovich, Casey; Ji, Tae-Geun; Lee, Hye-In

2016-08-01

We describe a preliminary conceptual optomechanical design for GMACS, a wide-field, multi-object, moderate resolution optical spectrograph for the Giant Magellan Telescope (GMT). This paper describes the details of the GMACS optomechanical conceptual design, including the requirements and considerations leading to the design, mechanisms, optical mounts, and predicted flexure performance.

HST image restoration: A comparison of pre- and post-servicing mission results

NASA Technical Reports Server (NTRS)

Hanisch, R. J.; Mo, J.

1992-01-01

A variety of image restoration techniques (e.g., Wiener filter, Lucy-Richardson, MEM) have been applied quite successfully to the aberrated HST images. The HST servicing mission (scheduled for late 1993 or early 1994) will install a corrective optics system (COSTAR) for the Faint Object Camera and spectrographs and replace the Wide Field/Planetary Camera with a second generation instrument (WF/PC-II) having its own corrective elements. The image quality is expected to be improved substantially with these new instruments. What then is the role of image restoration for the HST in the long term? Through a series of numerical experiments using model point-spread functions for both aberrated and unaberrated optics, we find that substantial improvements in image resolution can be obtained for post-servicing mission data using the same or similar algorithms as being employed now to correct aberrated images. Included in our investigations are studies of the photometric integrity of the restoration algorithms and explicit models for HST pointing errors (spacecraft jitter).

An Ultraviolet Spectrograph Concept for Exploring Ocean Worlds

NASA Astrophysics Data System (ADS)

Schindhelm, E. R.; Hendrix, A. R.; Fleming, B. T.

2018-05-01

UV spectroscopy can probe dust/ice composition of the surface or plumes via uniquely identifying features. We present a technology concept for a future planetary science UV multi-object imaging spectrograph.

The Ultraviolet Spectrograph (UVS) on ESA’s JUICE Mission

NASA Astrophysics Data System (ADS)

Gladstone, Randy; Retherford, K.; Steffl, A.; Eterno, J.; Davis, M.; Versteeg, M.; Greathouse, T.; Araujo, M.; Walther, B.; Persson, K.; Persyn, S.; Dirks, G.; McGrath, M.; Feldman, P.; Bagenal, F.; Spencer, J.; Schindhelm, E.; Fletcher, L.

2013-10-01

The Jupiter Icy Moons Explorer (JUICE) was selected in May 2012 as the first L-class mission of ESA’s Cosmic Vision Program. JUICE will launch in 2022 on a 7.6-year journey to the Jovian system, including a Venus and multiple Earth gravity assists, before entering Jupiter orbit in January 2030. JUICE will study the entire Jovian system for 3.5 years, concentrating on Europa, Ganymede, and Callisto, with the last 10 months spent in Ganymede orbit. The Ultraviolet Spectrograph (UVS) on JUICE was jointly selected by NASA and ESA as part of its ~130 kg payload of 11 scientific instruments. UVS is the fifth in a series of successful ultraviolet imaging spectrographs (Rosetta-Alice, New Horizons Pluto-Alice, LRO-LAMP) and is largely based on the most recent of these, Juno-UVS. It observes photons in the 55-210 nm wavelength range, at moderate spectral and spatial resolution along a 7.5-degree slit. A main entrance “airglow port” (AP) is used for most observations (e.g., airglow, aurora, surface mapping, and stellar occultations), while a separate “solar port” (SP) allows for solar occultations. Another aperture door, with a small hole through the centre, is used as a “high-spatial-resolution port” (HP) for detailed observations of bright targets. Time-tagging (pixel list mode) and programmable spectral imaging (histogram mode) allow for observational flexibility and optimal data management. As on Juno-UVS, the effects of penetrating electron radiation on electronic parts and data quality are substantially mitigated through contiguous shielding, filtering of pulse height amplitudes, management of high voltage settings, and careful use of radiation-hard, flight-tested parts. The science goals of UVS are to: 1) explore the atmospheres, plasma interactions, and surfaces of the Galilean satellites; 2) determine the dynamics, chemistry, and vertical structure of Jupiter’s upper atmosphere from equator to pole; and 3) investigate the Jupiter-Io connection by quantifying energy and mass flow in the Io atmosphere, neutral clouds, and torus. Here we present the salient features of the UVS instrument and describe the science we plan to address.

The Cosmic Evolution Through UV Spectroscopy (CETUS) Probe Mission Concept

NASA Astrophysics Data System (ADS)

Danchi, William; Heap, Sara; Woodruff, Robert; Hull, Anthony; Kendrick, Stephen E.; Purves, Lloyd; McCandliss, Stephan; Kelly Dodson, Greg Mehle, James Burge, Martin Valente, Michael Rhee, Walter Smith, Michael Choi, Eric Stoneking

2018-01-01

CETUS is a mission concept for an all-UV telescope with 3 scientific instruments: a wide-field camera, a wide-field multi-object spectrograph, and a point-source high-resolution and medium resolution spectrograph. It is primarily intended to work with other survey telescopes in the 2020’s (e.g. E-ROSITA (X-ray), LSST, Subaru, WFIRST (optical-near-IR), SKA (radio) to solve major, outstanding problems in astrophysics. In this poster presentation, we give an overview of CETUS key science goals and a progress report on the CETUS mission and instrument design.

Optical design of MEMS-based infrared multi-object spectrograph concept for the Gemini South Telescope

NASA Astrophysics Data System (ADS)

Chen, Shaojie; Sivanandam, Suresh; Moon, Dae-Sik

2016-08-01

We discuss the optical design of an infrared multi-object spectrograph (MOS) concept that is designed to take advantage of the multi-conjugate adaptive optics (MCAO) corrected field at the Gemini South telescope. This design employs a unique, cryogenic MEMS-based focal plane mask to select target objects for spectroscopy by utilizing the Micro-Shutter Array (MSA) technology originally developed for the Near Infrared Spectrometer (NIRSpec) of the James Webb Space Telescope (JWST). The optical design is based on all spherical refractive optics, which serves both imaging and spectroscopic modes across the wavelength range of 0.9-2.5 μm. The optical system consists of a reimaging system, MSA, collimator, volume phase holographic (VPH) grisms, and spectrograph camera optics. The VPH grisms, which are VPH gratings sandwiched between two prisms, provide high dispersing efficiencies, and a set of several VPH grisms provide the broad spectral coverage at high throughputs. The imaging mode is implemented by removing the MSA and the dispersing unit out of the beam. We optimize both the imaging and spectrographic modes simultaneously, while paying special attention to the performance of the pupil imaging at the cold stop. Our current design provides a 1' ♢ 1' and a 0.5' ♢ 1' field of views for imaging and spectroscopic modes, respectively, on a 2048 × 2048 pixel HAWAII-2RG detector array. The spectrograph's slit width and spectral resolving power are 0.18'' and 3,000, respectively, and spectra of up to 100 objects can be obtained simultaneously. We present the overall results of simulated performance using optical model we designed.

MEGARA spectrograph optics

NASA Astrophysics Data System (ADS)

Carrasco, E.; Sánchez-Blanco, E.; García-Vargas, M. L.; Gil de Paz, A.; Páez, G.; Gallego, J.; Sánchez, F. M.; Vílchez, J. M.

2012-09-01

MEGARA is the next optical Integral-Field Unit (IFU) and Multi-Object Spectrograph (MOS) for Gran Telescopio Canarias. The instrument offers two IFUs plus a Multi-Object Spectroscopy (MOS) mode: a large compact bundle covering 12.5 arcsec x 11.3 arcsec on sky with 100 μm fiber-core; a small compact bundle, of 8.5 arcsec x 6.7 arcsec with 70 μm fiber-core and a fiber MOS positioner that allows to place up to 100 mini-bundles, 7 fibers each, with 100 μm fiber-core, within a 3.5 arcmin x 3.5 arcmin field of view, around the two IFUs. The fibers, organized in bundles, end in the pseudo-slit plate, which will be placed at the entrance focal plane of the MEGARA spectrograph. The large IFU and MOS modes will provide intermediate to high spectral resolutions, R=6800-17000. The small IFU mode will provide R=8000-20000. All these resolutions are possible thanks to a spectrograph design based in the used of volume phase holographic gratings in combination with prisms to keep fixed the collimator and camera angle. The MEGARA optics is composed by a total of 53 large optical elements per spectrograph: the field lens, the collimator and the camera lenses plus the complete set of pupil elements including holograms, windows and prisms. INAOE, a partner of the GTC and a partner of MEGARA consortium, is responsible of the optics manufacturing and tests. INAOE will carry out this project working in an alliance with CIO. This paper summarizes the status of MEGARA spectrograph optics at the Preliminary Design Review, held on March 2012.

First light results from the HERMES spectrograph at the AAT

NASA Astrophysics Data System (ADS)

Sheinis, Andrew I.

2016-08-01

The High Efficiency and Resolution Multi Element Spectrograph, HERMES is a facility-class optical spectrograph for the AAT. It is designed primarily for Galactic Archeology, the first major attempt to create a detailed understanding of galaxy formation and evolution by studying the history of our own galaxy, the Milky Way. The goal of the Galactic Archeology with Hermes (GALAH) survey is to reconstruct the mass assembly history of the Milky Way, through a detailed spatially tagged abundance study of one million stars. The spectrograph is based at the Anglo Australian Telescope (AAT) and is fed by the existing 2dF robotic fiber positioning system. The spectrograph uses VPH-gratings to achieve a spectral resolving power of 28,000 in standard mode and also provides a high-resolution mode ranging between 40,000 to 50,000 using a slit mask. The GALAH survey requires a SNR greater than 100 for a star brightness of V=14. The total spectral coverage of the four channels is about 100nm between 370 and 1000nm for up to 392 simultaneous targets within the 2- degree field of view. Hermes was commissioned in late 2013, with the GALAH Pilot starting in parallel with the commissioning. The GALAH survey started in early 2014 is currently about 33% complete. We present a description of the motivating science; an overview the instrument; and a status report on GALAH Survey.

CARMENES instrument overview

NASA Astrophysics Data System (ADS)

Quirrenbach, A.; Amado, P. J.; Caballero, J. A.; Mundt, R.; Reiners, A.; Ribas, I.; Seifert, W.; Abril, M.; Aceituno, J.; Alonso-Floriano, F. J.; Ammler-von Eiff, M.; Antona Jiménez, R.; Anwand-Heerwart, H.; Azzaro, M.; Bauer, F.; Barrado, D.; Becerril, S.; Béjar, V. J. S.; Benítez, D.; Berdiñas, Z. M.; Cárdenas, M. C.; Casal, E.; Claret, A.; Colomé, J.; Cortés-Contreras, M.; Czesla, S.; Doellinger, M.; Dreizler, S.; Feiz, C.; Fernández, M.; Galadí, D.; Gálvez-Ortiz, M. C.; García-Piquer, A.; García-Vargas, M. L.; Garrido, R.; Gesa, L.; Gómez Galera, V.; González Álvarez, E.; González Hernández, J. I.; Grözinger, U.; Guàrdia, J.; Guenther, E. W.; de Guindos, E.; Gutiérrez-Soto, J.; Hagen, H.-J.; Hatzes, A. P.; Hauschildt, P. H.; Helmling, J.; Henning, T.; Hermann, D.; Hernández Castaño, L.; Herrero, E.; Hidalgo, D.; Holgado, G.; Huber, A.; Huber, K. F.; Jeffers, S.; Joergens, V.; de Juan, E.; Kehr, M.; Klein, R.; Kürster, M.; Lamert, A.; Lalitha, S.; Laun, W.; Lemke, U.; Lenzen, R.; López del Fresno, Mauro; López Martí, B.; López-Santiago, J.; Mall, U.; Mandel, H.; Martín, E. L.; Martín-Ruiz, S.; Martínez-Rodríguez, H.; Marvin, C. J.; Mathar, R. J.; Mirabet, E.; Montes, D.; Morales Muñoz, R.; Moya, A.; Naranjo, V.; Ofir, A.; Oreiro, R.; Pallé, E.; Panduro, J.; Passegger, V.-M.; Pérez-Calpena, A.; Pérez Medialdea, D.; Perger, M.; Pluto, M.; Ramón, A.; Rebolo, R.; Redondo, P.; Reffert, S.; Reinhardt, S.; Rhode, P.; Rix, H.-W.; Rodler, F.; Rodríguez, E.; Rodríguez-López, C.; Rodríguez-Pérez, E.; Rohloff, R.-R.; Rosich, A.; Sánchez-Blanco, E.; Sánchez Carrasco, M. A.; Sanz-Forcada, J.; Sarmiento, L. F.; Schäfer, S.; Schiller, J.; Schmidt, C.; Schmitt, J. H. M. M.; Solano, E.; Stahl, O.; Storz, C.; Stürmer, J.; Suárez, J. C.; Ulbrich, R. G.; Veredas, G.; Wagner, K.; Winkler, J.; Zapatero Osorio, M. R.; Zechmeister, M.; Abellán de Paco, F. J.; Anglada-Escudé, G.; del Burgo, C.; Klutsch, A.; Lizon, J. L.; López-Morales, M.; Morales, J. C.; Perryman, M. A. C.; Tulloch, S. M.; Xu, W.

2014-07-01

This paper gives an overview of the CARMENES instrument and of the survey that will be carried out with it during the first years of operation. CARMENES (Calar Alto high-Resolution search for M dwarfs with Exoearths with Near-infrared and optical Echelle Spectrographs) is a next-generation radial-velocity instrument under construction for the 3.5m telescope at the Calar Alto Observatory by a consortium of eleven Spanish and German institutions. The scientific goal of the project is conducting a 600-night exoplanet survey targeting ~ 300 M dwarfs with the completed instrument. The CARMENES instrument consists of two separate echelle spectrographs covering the wavelength range from 0.55 to 1.7 μm at a spectral resolution of R = 82,000, fed by fibers from the Cassegrain focus of the telescope. The spectrographs are housed in vacuum tanks providing the temperature-stabilized environments necessary to enable a 1 m/s radial velocity precision employing a simultaneous calibration with an emission-line lamp or with a Fabry-Perot etalon. For mid-M to late-M spectral types, the wavelength range around 1.0 μm (Y band) is the most important wavelength region for radial velocity work. Therefore, the efficiency of CARMENES has been optimized in this range. The CARMENES instrument consists of two spectrographs, one equipped with a 4k x 4k pixel CCD for the range 0.55 - 1.05 μm, and one with two 2k x 2k pixel HgCdTe detectors for the range from 0.95 - 1.7μm. Each spectrograph will be coupled to the 3.5m telescope with two optical fibers, one for the target, and one for calibration light. The front end contains a dichroic beam splitter and an atmospheric dispersion corrector, to feed the light into the fibers leading to the spectrographs. Guiding is performed with a separate camera; on-axis as well as off-axis guiding modes are implemented. Fibers with octagonal cross-section are employed to ensure good stability of the output in the presence of residual guiding errors. The fibers are continually actuated to reduce modal noise. The spectrographs are mounted on benches inside vacuum tanks located in the coudé laboratory of the 3.5m dome. Each vacuum tank is equipped with a temperature stabilization system capable of keeping the temperature constant to within +/-0.01°C over 24 hours. The visible-light spectrograph will be operated near room temperature, while the near-IR spectrograph will be cooled to ~ 140 K. The CARMENES instrument passed its final design review in February 2013. The MAIV phase is currently ongoing. First tests at the telescope are scheduled for early 2015. Completion of the full instrument is planned for the fall of 2015. At least 600 useable nights have been allocated at the Calar Alto 3.5m Telescope for the CARMENES survey in the time frame until 2018. A data base of M stars (dubbed CARMENCITA) has been compiled from which the CARMENES sample can be selected. CARMENCITA contains information on all relevant properties of the potential targets. Dedicated imaging, photometric, and spectroscopic observations are underway to provide crucial data on these stars that are not available in the literature.

VizieR Online Data Catalog: Spectroscopy of 104 objects in the ONC (Ingraham+, 2014)

NASA Astrophysics Data System (ADS)

Ingraham, P.; Albert, L.; Doyon, R.; Artigau, E.

2016-03-01

In 2003 December, we obtained six nights (on CFHT to perform MOS observations of faint objects in the central region of the Orion Trapezium cluster. The observations used the infrared imager and multi-object spectrograph SIMON (Spectrometre Infrarouge de Montreal). The optical design is fully achromatic between 0.8 and 2.5μm and features a HAWAII-I 1024*1024 HgCdTe detector with an image scale of 0.2'' on CFHT. SIMON utilizes a low-dispersion Amici prism enabling multi-object low-resolution (R~30) spectroscopy over the wavelength range of 0.9-2.4μm. The slit width, in the spectral direction, was chosen to be 0.6'' (3pixels) resulting in a spectral resolution of R~30. In total, spectra for 240 point sources were obtained. Here, we present only the 104 objects (see Table5) with low-extinction (AV<8) spectra having well constrained spectral types. (2 data files).

The SAMI Galaxy Survey: cubism and covariance, putting round pegs into square holes

NASA Astrophysics Data System (ADS)

Sharp, R.; Allen, J. T.; Fogarty, L. M. R.; Croom, S. M.; Cortese, L.; Green, A. W.; Nielsen, J.; Richards, S. N.; Scott, N.; Taylor, E. N.; Barnes, L. A.; Bauer, A. E.; Birchall, M.; Bland-Hawthorn, J.; Bloom, J. V.; Brough, S.; Bryant, J. J.; Cecil, G. N.; Colless, M.; Couch, W. J.; Drinkwater, M. J.; Driver, S.; Foster, C.; Goodwin, M.; Gunawardhana, M. L. P.; Ho, I.-T.; Hampton, E. J.; Hopkins, A. M.; Jones, H.; Konstantopoulos, I. S.; Lawrence, J. S.; Leslie, S. K.; Lewis, G. F.; Liske, J.; López-Sánchez, Á. R.; Lorente, N. P. F.; McElroy, R.; Medling, A. M.; Mahajan, S.; Mould, J.; Parker, Q.; Pracy, M. B.; Obreschkow, D.; Owers, M. S.; Schaefer, A. L.; Sweet, S. M.; Thomas, A. D.; Tonini, C.; Walcher, C. J.

2015-01-01

We present a methodology for the regularization and combination of sparse sampled and irregularly gridded observations from fibre-optic multiobject integral field spectroscopy. The approach minimizes interpolation and retains image resolution on combining subpixel dithered data. We discuss the methodology in the context of the Sydney-AAO multiobject integral field spectrograph (SAMI) Galaxy Survey underway at the Anglo-Australian Telescope. The SAMI instrument uses 13 fibre bundles to perform high-multiplex integral field spectroscopy across a 1° diameter field of view. The SAMI Galaxy Survey is targeting ˜3000 galaxies drawn from the full range of galaxy environments. We demonstrate the subcritical sampling of the seeing and incomplete fill factor for the integral field bundles results in only a 10 per cent degradation in the final image resolution recovered. We also implement a new methodology for tracking covariance between elements of the resulting data cubes which retains 90 per cent of the covariance information while incurring only a modest increase in the survey data volume.

VizieR Online Data Catalog: RAVE J203843.2-002333 high-resolution spectroscopy (Placco+, 2017)

NASA Astrophysics Data System (ADS)

Placco, V. M.; Holmbeck, E. M.; Frebel, A.; Beers, T. C.; Surman, R. A.; Ji, A. P.; Ezzeddine, R.; Points, S. D.; Kaleida, C. C.; Hansen, T. T.; Sakari, C. M.; Casey, A. R.

2018-03-01

Medium-resolution spectroscopic follow-up was carried out with the Mayall 4m Telescope at Kitt Peak National Observatory. The observations were obtained in semester 2014B, using the R-C spectrograph covering the wavelength range [3500,6000]Å (R~1600). High-resolution spectroscopic data were obtained during the 2014B and 2016A semesters, using the Magellan Inamori Kyocera Echelle (MIKE) spectrograph on the Magellan/Clay Telescope at Las Campanas Observatory. For the 2014B run, the setup yielding a resolving power of R~38000 (blue spectral range) and R~30000 (red spectral range). For the 2016A run, the resolving power was R~66000 (coverage [~3500,9000]Å). (4 data files).

Extra Solar Planet Science With a Non Redundant Mask

NASA Astrophysics Data System (ADS)

Minto, Stefenie Nicolet; Sivaramakrishnan, Anand; Greenbaum, Alexandra; St. Laurent, Kathryn; Thatte, Deeparshi

2017-01-01

To detect faint planetary companions near a much brighter star, at the Resolution Limit of the James Webb Space Telescope (JWST) the Near-Infrared Imager and Slitless Spectrograph (NIRISS) will use a non-redundant aperture mask (NRM) for high contrast imaging. I simulated NIRISS data of stars with and without planets, and run these through the code that measures interferometric image properties to determine how sensitive planetary detection is to our knowledge of instrumental parameters, starting with the pixel scale. I measured the position angle, distance, and contrast ratio of the planet (with respect to the star) to characterize the binary pair. To organize this data I am creating programs that will automatically and systematically explore multi-dimensional instrument parameter spaces and binary characteristics. In the future my code will also be applied to explore any other parameters we can simulate.

An Overview of the HST Advanced Camera for Surveys' On-orbit Performance

NASA Astrophysics Data System (ADS)

Hartig, G. F.; Ford, H. C.; Illingworth, G. D.; Clampin, M.; Bohlin, R. C.; Cox, C.; Krist, J.; Sparks, W. B.; De Marchi, G.; Martel, A. R.; McCann, W. J.; Meurer, G. R.; Sirianni, M.; Tsvetanov, Z.; Bartko, F.; Lindler, D. J.

2002-05-01

The Advanced Camera for Surveys (ACS) was installed in the HST on 7 March 2002 during the fourth servicing mission to the observatory, and is now beginning science operations. The ACS provides HST observers with a considerably more sensitive, higher-resolution camera with wider field and polarimetric, coronagraphic, low-resolution spectrographic and solar-blind FUV capabilities. We review selected results of the early verification and calibration program, comparing the achieved performance with the advertised specifications. Emphasis is placed on the optical characteristics of the camera, including image quality, throughput, geometric distortion and stray-light performance. More detailed analyses of various aspects of the ACS performance are presented in other papers at this meeting. This work was supported by a NASA contract and a NASA grant.

Classification of High Spatial Resolution, Hyperspectral ...

EPA Pesticide Factsheets

EPA announced the availability of the final report,

Very high spatial resolution two-dimensional solar spectroscopy with video CCDs

NASA Technical Reports Server (NTRS)

Johanneson, A.; Bida, T.; Lites, B.; Scharmer, G. B.

1992-01-01

We have developed techniques for recording and reducing spectra of solar fine structure with complete coverage of two-dimensional areas at very high spatial resolution and with a minimum of seeing-induced distortions. These new techniques permit one, for the first time, to place the quantitative measures of atmospheric structure that are afforded only by detailed spectral measurements into their proper context. The techniques comprise the simultaneous acquisition of digital spectra and slit-jaw images at video rates as the solar scene sweeps rapidly by the spectrograph slit. During data processing the slit-jaw images are used to monitor rigid and differential image motion during the scan, allowing measured spectrum properties to be remapped spatially. The resulting quality of maps of measured properties from the spectra is close to that of the best filtergrams. We present the techniques and show maps from scans over pores and small sunspots obtained at a resolution approaching 1/3 arcsec in the spectral region of the magnetically sensitive Fe I lines at 630.15 and 630.25 nm. The maps shown are of continuum intensity and calibrated Doppler velocity. More extensive spectral inversion of these spectra to yield the strength of the magnetic field and other parameters is now underway, and the results of that analysis will be presented in a following paper.

Classification of PSN J13505285-3017097 as an old Type Ia SN with WiFeS

NASA Astrophysics Data System (ADS)

Childress, M.; Scalzo, R.; Tucker, B.; Yuan, F.; Schmidt, B.; Klotz, A.; Conseil, E.

2013-06-01

We report spectroscopic classification of PSN J13505285-3017097 with the Wide Field Spectrograph (WiFeS - Dopita et al., 2007, ApSS, 310, 255) on the ANU 2.3m telescope at Siding Spring Observatory, NSW Australia, using the B3000/R3000 gratings (3500-9800 A, 1 A resolution). PSN J13505285-3017097 was discovered by Conseil on 2013 May 02.22 at mag 18.4 on TAROT images, and photometric follow up shows the light curve peaks in brightness at mag 16 on 2013 May 15.

Constraints on active region coronal heating properties from observations and modeling of chromospheric, transition region, and coronal emission

NASA Astrophysics Data System (ADS)

Testa, P.; Polito, V.; De Pontieu, B.; Carlsson, M.; Reale, F.; Allred, J. C.; Hansteen, V. H.

2017-12-01

We investigate coronal heating properties in active region cores in non-flaring conditions, using high spatial, spectral, and temporal resolution chromospheric/transition region/coronal observations coupled with detailed modeling. We will focus, in particular, on observations with the Interface Region Imaging Spectrograph (IRIS), joint with observations with Hinode (XRT and EIS) and SDO/AIA. We will discuss how these observations and models (1D HD and 3D MHD, with the RADYN and Bifrost codes) provide useful diagnostics of the coronal heating processes and mechanisms of energy transport.

Spectrographic imaging system

DOEpatents

Morris, Michael D.; Treado, Patrick J.

1991-01-01

An imaging system for providing spectrographically resolved images. The system incorporates a one-dimensional spatial encoding mask which enables an image to be projected onto a two-dimensional image detector after spectral dispersion of the image. The dimension of the image which is lost due to spectral dispersion on the two-dimensional detector is recovered through employing a reverse transform based on presenting a multiplicity of different spatial encoding patterns to the image. The system is especially adapted for detecting Raman scattering of monochromatic light transmitted through or reflected from physical samples. Preferably, spatial encoding is achieved through the use of Hadamard mask which selectively transmits or blocks portions of the image from the sample being evaluated.

Deriving Atmospheric Properties and Escape Rates from MAVEN's Imaging UV Spectrograph (IUVS)

NASA Astrophysics Data System (ADS)

Schneider, Nicholas M.; IUVS Science Team

2013-10-01

MAVEN (Mars Volatile and Atmosphere EvolutioN) is a Mars Scout mission being readied for launch in November 2013. The key hardware and management partners are University of Colorado, Goddard Space Flight Center, University of California at Berkeley, Lockheed Martin, and the Jet Propulsion Laboratory. MAVEN carries a powerful suite of fields and particles instruments and a sophisticated remote sensing instrument, the Imaging UltraViolet Spectrograph (IUVS). This presentation begins by describing IUVS' science goals, instrument design, operational approach and data analysis strategy. IUVS supports the top-level MAVEN science goals: measure the present state of the atmosphere, observe its response to varying solar stimuli, and use the information to estimate loss from Mars' atmosphere over time. The instrument operates at low spectral resolution spanning the FUV and MUV ranges in separate channels, and at high resolution around the hydrogen Lyman alpha line to measure the D/H ratio in the upper atmosphere. MAVEN carries the instrument on an Articulated Payload Platform which orients the instrument for optimal observations during four segments of its 4.5 hr elliptical orbit. During periapse passage, IUVS uses a scan mirror to obtain vertical profiles of emissions from the atmosphere and ionosphere. Around apoapse, the instrument builds up low-resolution images of the atmosphere at multiple wavelengths. In between, the instrument measures emissions from oxygen, hydrogen and deuterium in the corona. IUVS also undertakes day-long stellar occultation campaigns at 2 month intervals, to measure the state of the atmosphere at altitudes below the airglow layer and in situ sampling. All data will be pipeline-processed from line brightnesses to column abundances, local densities and global 3-D maps. The focus of the presentation is development of these automatic processing algorithms and the data products they will provide to the Mars community through the PDS Atmospheres Node. The combined results from all instruments on ion and neutral escape will bear on the central question of the history of Mars' atmosphere and climate history. This work has been supported by NASA's MAVEN mission.

PISCES: An Integral Field Spectrograph Technology Demonstration for the WFIRST Coronagraph

NASA Technical Reports Server (NTRS)

McElwain, Michael W.; Mandell, Avi M.; Gong, Qian; Llop-Sayson, Jorge; Brandt, Timothy; Chambers, Victor J.; Grammer, Bryan; Greeley, Bradford; Hilton, George; Perrin, Marshall D.;

PISCES: an integral field spectrograph technology demonstration for the WFIRST coronagraph

NASA Astrophysics Data System (ADS)

McElwain, Michael W.; Mandell, Avi M.; Gong, Qian; Llop-Sayson, Jorge; Brandt, Timothy; Chambers, Victor J.; Grammer, Bryan; Greeley, Bradford; Hilton, George; Perrin, Marshall D.; Stapelfeldt, Karl R.; Demers, Richard; Tang, Hong; Cady, Eric

2016-07-01

We present the design, integration, and test of the Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) integral field spectrograph (IFS). The PISCES design meets the science requirements for the Wide-Field InfraRed Survey Telescope (WFIRST) Coronagraph Instrument (CGI). PISCES was integrated and tested in the integral field spectroscopy laboratory at NASA Goddard. In June 2016, PISCES was delivered to the Jet Propulsion Laboratory (JPL) where it was integrated with the Shaped Pupil Coronagraph (SPC) High Contrast Imaging Testbed (HCIT). The SPC/PISCES configuration will demonstrate high contrast integral field spectroscopy as part of the WFIRST CGI technology development program.

Exploring the Universe with the Hubble Space Telescope

NASA Technical Reports Server (NTRS)

1990-01-01

A general overview is given of the operations, engineering challenges, and components of the Hubble Space Telescope. Deployment, checkout and servicing in space are discussed. The optical telescope assembly, focal plane scientific instruments, wide field/planetary camera, faint object spectrograph, faint object camera, Goddard high resolution spectrograph, high speed photometer, fine guidance sensors, second generation technology, and support systems and services are reviewed.

The SED Machine: a dedicated transient IFU spectrograph

NASA Astrophysics Data System (ADS)

Ben-Ami, Sagi; Konidaris, Nick; Quimby, Robert; Davis, Jack T.; Ngeow, Chow Choong; Ritter, Andreas; Rudy, Alexander

2012-09-01

The Spectral Energy Distribution (SED) Machine is an Integral Field Unit (IFU) spectrograph designed specifically to classify transients. It is comprised of two subsystems. A lenselet based IFU, with a 26" × 26" Field of View (FoV) and ˜ 0.75" spaxels feeds a constant resolution (R˜100) triple-prism. The dispersed rays are than imaged onto an off-the-shelf CCD detector. The second subsystem, the Rainbow Camera (RC), is a 4-band seeing-limited imager with a 12.5' × 12.5' FoV around the IFU that will allow real time spectrophotometric calibrations with a ˜ 5% accuracy. Data from both subsystems will be processed in real time using a dedicated reduction pipeline. The SED Machine will be mounted on the Palomar 60-inch robotic telescope (P60), covers a wavelength range of 370 - 920nm at high throughput and will classify transients from on-going and future surveys at a high rate. This will provide good statistics for common types of transients, and a better ability to discover and study rare and exotic ones. We present the science cases, optical design, and data reduction strategy of the SED Machine. The SED machine is currently being constructed at the Calofornia Institute of Technology, and will be comissioned on the spring of 2013.

VizieR Online Data Catalog: Bubble HII region Sh2-39 (N5) (Duronea+, 2017)

NASA Astrophysics Data System (ADS)

Duronea, N. U.; Cappa, C. E.; Bronfman, L.; Borissova, J.; Gromadzki, M.; Kuhn, M. A.

2017-06-01

The molecular observations were carried out in August 2015 with the 10m Atacama Submillimeter Telescope Experiment (ASTE). We used DASH345, a two sideband single-polarization heterodyne receiver, tunable in LO frequency range from 327GHz to 370GHz at observable frequency range from 321GHz to 376GHz. The XF digital spectrometer was set to a bandwidth and spectral resolution of 128MHz and 125KHz, respectively. The spectral velocity resolution was 0.11km/s, the half power beamwidth (HPBW) is ~22", and the main beam efficiency (mb) is 0.65. Observations were made using the on-the-fly (OTF) mode with two orthogonal scan directions along RA and Dec. (J2000) centered on RA, Dec.(J2000)= (18:17:02.1, -18:40:19). We observed simultaneously the lines CO(3-2) (345.796GHz) and HCO+(4-3) (356.734) in a region of ~17'x17' (see Fig. 1). The spectra were reduced with NOSTAR2 using the standard procedure. The brightest star projected at the center of [BDS2003] 6 (2MASS J18165113-1841488) was observed on August 2016 with Astronomy Research using the Cornell Infra Red Imaging Spectrograph (ARCoIRIS), a cross-dispersed, single-object, longslit, infrared imaging spectrograph,mounted on Blanco 4-m Telescope, CTIO. The spectra cover a simultaneous wavelength range of 0.80 to 2.47um, at a spectral resolution of about 3500 λ{δλ, encompassing the entire zYJHK photometric range. The spectrum was taken with 480 sec integration time, at 1.03 average airmass. The HD163336 telluric A0 V standard is observed immediately after target. The basic steps of the reduction procedure are described in Chene et al. (2012A&A...545A..54C, Cat. J/A+A/545/A54, 2013A&A...549A..98C). We used the corresponding pipeline. (3 data files).

Lhires III High Resolution Spectrograph

NASA Astrophysics Data System (ADS)

Thizy, O.

2007-05-01

By spreading the light from celestial objects by wavelength, spectroscopists are like detectives looking for clues and identifying guilty phenomena that shape their spectra. We will review some basic principles in spectroscopy that will help, at our amateur level, to understand how spectra are shaped. We will review the Lhires III highresolution spectrograph Mark Three that was designed to reveal line profile details and subtle changes. Then, we will do an overview of educational and scientific projects that are conducted with the Lhires III and detail the COROT Be star program and the BeSS database for which the spectrograph is a key instrument.

A soft x-ray octadecyl hydrogen maleate crystal spectrograph

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

Fan, P.Z.; Fill, E.E.; Tietang, G.

1996-03-01

A crystal spectrograph is described which can be used to investigate laser-produced plasmas in the region of soft x rays at wavelengths of up to 60 A. The spectrograph uses an octadecyl hydrogen maleate crystal with a 2{ital d} of 63.5 A, combined with a very thin carbon filter (3000 A thick). As examples of its application, soft x-ray spectra in the range of 43{endash}51 A from laser plasmas of Si and Cu are presented. A spectral resolution of {lambda}/{Delta}{lambda}=1100 is deduced from the spectra. {copyright} {ital 1996 American Institute of Physics.}

VizieR Online Data Catalog: The AllWISE motion survey (AllWISE2) (Kirkpatrick+, 2016)

NASA Astrophysics Data System (ADS)

Kirkpatrick, J. D.; Kellogg, K.; Schneider, A. C.; Fajardo-Acosta, S.; Cushing, M. C.; Greco, J.; Mace, G. N.; Gelino, C. R.; Wright, E. L.; Eisenhardt, P. R. M.; Stern, D.; Faherty, J. K.; Sheppard, S. S.; Lansbury, G. B.; Logsdon, S. E.; Martin, E. C.; McLean, I. S.; Schurr, S. D.; Cutri, R. M.; Conrow, T.

2016-07-01

Observations for the spectroscopic follow-up of interesting AllWISE sources are listed in Table 4. Optical follow-up was conducted with the Palomar/Double Spectrograph on the Hale 5m telescope on Palomar Mountain, California, as our primary optical spectrograph in the northern hemisphere. It was used during the UT nights of 2014 January 26, February 23/24, April 22, June 25/26, July 21, September 27, October 24, and November 15 as well as 2015 June 08, September 07, and December 10. The Boller & Chivens Spectrograph (BCSpec) on the 2.5m Irenee duPont telescope at Las Campanas Observatory, Chile, served as our primary optical spectrograph in the southern hemisphere and was used on the UT nights of 2014 April 30, May 01-04, and November 16-20. Spectra of 10 objects were obtained on the UT nights of 2014 July 03-04 and 2015 December 07-10 at the European Southern Observatory (ESO) 3.58m New Technology Telescope (NTT) at La Silla, Chile. Spectra of seven objects were obtained on the UT nights of 2014 June 26, 2015 August 13, and 2015 December 05 with the Low Resolution Imaging Spectrometer (LRIS) at the 10m W. M. Keck Observatory on Mauna Kea, Hawaii. SpeX on the NASA 3m Infrared Telescope Facility (IRTF) on Mauna Kea, Hawaii, served as our primary near-infrared spectrograph in the northern hemisphere. The UT dates of observation were 2014 November 11 and 2015 January 27, May 08-09, June 27, July 03-05, and July 20. The Folded-port Infrared Echellette (FIRE) at the 6.5m Walter Baade Telescope at Las Campanas Observatory, Chile, served as our primary near-infrared spectrograph in the southern hemisphere. The UT dates of observation were 2014 August 07-09, 2015 February 08, and 2015 May 31. Several sources were also observed with the Near-Infrared Spectrometer (NIRSPEC) at the 10m W. M. Keck Observatory on Mauna Kea, Hawaii. The observation dates were UT 2014 April 12 and December 03, and 2015 July 03 and July 11. (9 data files).

SALT high resolution spectroscopy of GX339-4 in outburst

NASA Astrophysics Data System (ADS)

Buckley, D. A. H.; Aydi, E.; Kotze, M. M.; Gandhi, P.; Altamirano, D.; Charles, P. A.; Russell, D.

2017-10-01

High resolution (R = 15,000) spectroscopy of the current outbursting black hole transient GX339-4 (ATel #10797) was obtained with the SALT High Resolution Spectrograph (HRS; Crause et al. 2014, Proc SPIE, 91476) on 2017-09-29 starting at 17:28 UTC, during evening twilight.

Minor Distortions with Major Consequences: Correcting Distortions in Imaging Spectrographs

PubMed Central

Esmonde-White, Francis W. L.; Esmonde-White, Karen A.; Morris, Michael D.

2010-01-01

Projective transformation is a mathematical correction (implemented in software) used in the remote imaging field to produce distortion-free images. We present the application of projective transformation to correct minor alignment and astigmatism distortions that are inherent in dispersive spectrographs. Patterned white-light images and neon emission spectra were used to produce registration points for the transformation. Raman transects collected on microscopy and fiber-optic systems were corrected using established methods and compared with the same transects corrected using the projective transformation. Even minor distortions have a significant effect on reproducibility and apparent fluorescence background complexity. Simulated Raman spectra were used to optimize the projective transformation algorithm. We demonstrate that the projective transformation reduced the apparent fluorescent background complexity and improved reproducibility of measured parameters of Raman spectra. Distortion correction using a projective transformation provides a major advantage in reducing the background fluorescence complexity even in instrumentation where slit-image distortions and camera rotation were minimized using manual or mechanical means. We expect these advantages should be readily applicable to other spectroscopic modalities using dispersive imaging spectrographs. PMID:21211158

A high resolution ultraviolet Shuttle glow spectrograph

NASA Technical Reports Server (NTRS)

Carruthers, George R.

1993-01-01

The High Resolution Shuttle Glow Spectrograph-B (HRSGS-B) is a small payload being developed by the Naval Research Laboratory. It is intended for study of shuttle surface glow in the 180-400 nm near- and middle-ultraviolet wavelength range, with a spectral resolution of 0.2 nm. It will search for, among other possible features, the band systems of excited NO which result from surface-catalyzed combination of N and O. It may also detect O2 Hertzberg bands and N2 Vegard-Kaplan bands resulting from surface recombination. This wavelength range also includes possible N2+ and OH emissions. The HRSGS-B will be housed in a Get Away Special canister, mounted in the shuttle orbiter payload bay, and will observe the glow on the tail of the orbiter.

Spectroscopic classification of Gaia17apq and Gaia17apv with Double Spectrograph on Palomar 200-inch telescope

NASA Astrophysics Data System (ADS)

Blagorodnova, N.; Adams, S.

2017-03-01

We report the classification of Gaia17apq and Gaia17apv (SN2017cao and SN2017cat), discovered by the Gaia ESA survey. The observations were performed on UT 2017-03-16 with the Double Spectrograph (DBSP; range 350-1000nm, spectral resolution R 4000) on Palomar 200-inch (P200) telescope.

Performance of the CHIRON high-resolution Echelle spectrograph

NASA Astrophysics Data System (ADS)

Schwab, Christian; Spronck, Julien F. P.; Tokovinin, Andrei; Szymkowiak, Andrew; Giguere, Matthew; Fischer, Debra A.

2012-09-01

CHIRON is a fiber-fed Echelle spectrograph with observing modes for resolutions from 28,000 to 120,000, built primarily for measuring precise radial velocities (RVs). We present the instrument performance as determined during integration and commissioning. We discuss the PSF, the effect of glass inhomogeneity on the cross-dispersion prism, temperature stabilization, stability of the spectrum on the CCD, and detector characteristics. The RV precision is characterized, with an iodine cell or a ThAr lamp as the wavelength reference. Including all losses from the sky to the detector, the overall efficiency is about 6%; the dominant limitation is coupling losses into the fiber due to poor guiding.

The LUVOIR Large Mission Concept

NASA Astrophysics Data System (ADS)

O'Meara, John; LUVOIR Science and Technology Definition Team

2018-01-01

LUVOIR is one of four large mission concepts for which the NASA Astrophysics Division has commissioned studies by Science and Technology Definition Teams (STDTs) drawn from the astronomical community. We are currently developing two architectures: Architecture A with a 15.1 meter segmented primary mirror, and Architecture B with a 9.2 meter segmented primary mirror. Our focus in this presentation is the Architecture A LUVOIR. LUVOIR will operate at the Sun-Earth L2 point. It will be designed to support a broad range of astrophysics and exoplanet studies. The initial instruments developed for LUVOIR Architecture A include 1) a high-performance optical/NIR coronagraph with imaging and spectroscopic capability, 2) a UV imager and spectrograph with high spectral resolution and multi-object capability, 3) a high-definition wide-field optical/NIR camera, and 4) a high resolution UV/optical spectropolarimeter. LUVOIR will be designed for extreme stability to support unprecedented spatial resolution and coronagraphy. It is intended to be a long-lifetime facility that is both serviceable, upgradable, and primarily driven by guest observer science programs. In this presentation, we will describe the observatory, its instruments, and survey the transformative science LUVOIR can accomplish.

Remote Sensing of the Upper Atmosphere and the Ionosphere in the Extreme and Far Ultraviolet: Results from the LITES Experiment aboard the IS

NASA Astrophysics Data System (ADS)

Finn, S. C.; Chakrabarti, S.; Stephan, A. W.; Geddes, G.; Budzien, S. A.; Cook, T.; Aryal, S.; Martel, J.; Galkin, I. A.; Erickson, P. J.

2017-12-01

The Limb-Imaging Ionospheric and Thermospheric Extreme-ultraviolet Spectrograph (LITES) was launched as part of the Space Test Program Houston #5 (STP-H5) payload aboard a commercial resupply flight on February 19, 2017 and was subsequently installed on the International Space Station (ISS). LITES is an imaging spectrograph that spans the 60 - 140 nm wavelength range at 1 nm spectral resolution and samples tangent altitudes 150 - 350 km with 0.2° angular resolution. LITES, in combination with the GPS Radio Occultation and Ultraviolet Photometry - Colocated (GROUP-C) experiment, which includes a GPS receiver and a nadir viewing 135.6 nm photometer, jointly collect new information on the thermosphere and the ionosphere using simultaneous UV and radio emissions. LITES, which uses standard stars to perform in-flight calibration, observes altitude profiles of day and night airglow emissions that are being used to infer thermospheric and ionospheric density profiles. Furthermore, due to the inclination of the ISS, LITES has also observed auroral spectrum and their altitude and spatial variations. Finally, geomagnetic storm effects on its UV emissions can be used to remotely sense their effects on the upper atmospheric morphology. These ISS observations,which are complement to the upcoming ICON and GOLD NASA missions, are focused on ionosphere-atmosphere coupling and global-scale atmospheric response to space weather observed from higher altitudes . We will present an overview of the LITES instrument, some early results from the first few months of operations. We will also summarize the advantages in calibration and validation activities that are possible through space-based LITES, GROUP-C and stellar measurements and simultaneous ground-based optical and radar observations.

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

De Pontieu, B.; Martinez-Sykora, J.; McIntosh, S.

Spectral observations of the solar transition region (TR) and corona show broadening of spectral lines beyond what is expected from thermal and instrumental broadening. The remaining non-thermal broadening is significant (5–30 km s{sup −1}) and correlated with intensity. Here we study spectra of the TR Si iv 1403 Å line obtained at high resolution with the Interface Region Imaging Spectrograph (IRIS). We find that the large improvement in spatial resolution (0.″33) of IRIS compared to previous spectrographs (2″) does not resolve the non-thermal line broadening which, in most regions, remains at pre-IRIS levels of about 20 km s{sup −1}. Thismore » invariance to spatial resolution indicates that the processes behind the broadening occur along the line-of-sight (LOS) and/or on spatial scales (perpendicular to the LOS) smaller than 250 km. Both effects appear to play a role. Comparison with IRIS chromospheric observations shows that, in regions where the LOS is more parallel to the field, magneto-acoustic shocks driven from below impact the TR and can lead to significant non-thermal line broadening. This scenario is supported by MHD simulations. While these do not show enough non-thermal line broadening, they do reproduce the long-known puzzling correlation between non-thermal line broadening and intensity. This correlation is caused by the shocks, but only if non-equilibrium ionization is taken into account. In regions where the LOS is more perpendicular to the field, the prevalence of small-scale twist is likely to play a significant role in explaining the invariance and correlation with intensity. (letters)« less

Optomechanical design concept for GMACS: a wide-field multi-object moderate resolution optical spectrograph for the Giant Magellan Telescope (GMT)

NASA Astrophysics Data System (ADS)

Smee, Stephen A.; Prochaska, Travis; Shectman, Stephen A.; Hammond, Randolph P.; Barkhouser, Robert H.; DePoy, D. L.; Marshall, J. L.

2012-09-01

We describe the conceptual optomechanical design for GMACS, a wide-field, multi-object, moderate-resolution optical spectrograph for the Giant Magellan Telescope (GMT). GMACS is a candidate first-light instrument for the GMT and will be one of several instruments housed in the Gregorian Instrument Rotator (GIR) located at the Gregorian focus. The instrument samples a 9 arcminute x 18 arcminute field of view providing two resolution modes (i.e, low resolution, R ~ 2000, and moderate resolution, R ~ 4000) over a 3700 Å to 10200 Å wavelength range. To minimize the size of the optics, four fold mirrors at the GMT focal plane redirect the full field into four individual "arms", that each comprises a double spectrograph with a red and blue channel. Hence, each arm samples a 4.5 arcminute x 9 arcminute field of view. The optical layout naturally leads to three separate optomechanical assemblies: a focal plane assembly, and two identical optics modules. The focal plane assembly contains the last element of the telescope's wide-field corrector, slit-mask, tent-mirror assembly, and slit-mask magazine. Each of the two optics modules supports two of the four instrument arms and houses the aft-optics (i.e. collimators, dichroics, gratings, and cameras). A grating exchange mechanism, and articulated gratings and cameras facilitate multiple resolution modes. In this paper we describe the details of the GMACS optomechanical design, including the requirements and considerations leading to the design, mechanism details, optics mounts, and predicted flexure performance.

Adaptive optics at the Subaru telescope: current capabilities and development

NASA Astrophysics Data System (ADS)

Guyon, Olivier; Hayano, Yutaka; Tamura, Motohide; Kudo, Tomoyuki; Oya, Shin; Minowa, Yosuke; Lai, Olivier; Jovanovic, Nemanja; Takato, Naruhisa; Kasdin, Jeremy; Groff, Tyler; Hayashi, Masahiko; Arimoto, Nobuo; Takami, Hideki; Bradley, Colin; Sugai, Hajime; Perrin, Guy; Tuthill, Peter; Mazin, Ben

2014-08-01

Current AO observations rely heavily on the AO188 instrument, a 188-elements system that can operate in natural or laser guide star (LGS) mode, and delivers diffraction-limited images in near-IR. In its LGS mode, laser light is transported from the solid state laser to the launch telescope by a single mode fiber. AO188 can feed several instruments: the infrared camera and spectrograph (IRCS), a high contrast imaging instrument (HiCIAO) or an optical integral field spectrograph (Kyoto-3DII). Adaptive optics development in support of exoplanet observations has been and continues to be very active. The Subaru Coronagraphic Extreme-AO (SCExAO) system, which combines extreme-AO correction with advanced coronagraphy, is in the commissioning phase, and will greatly increase Subaru Telescope's ability to image and study exoplanets. SCExAO currently feeds light to HiCIAO, and will soon be combined with the CHARIS integral field spectrograph and the fast frame MKIDs exoplanet camera, which have both been specifically designed for high contrast imaging. SCExAO also feeds two visible-light single pupil interferometers: VAMPIRES and FIRST. In parallel to these direct imaging activities, a near-IR high precision spectrograph (IRD) is under development for observing exoplanets with the radial velocity technique. Wide-field adaptive optics techniques are also being pursued. The RAVEN multi-object adaptive optics instrument was installed on Subaru telescope in early 2014. Subaru Telescope is also planning wide field imaging with ground-layer AO with the ULTIMATE-Subaru project.

The Magellan Telescopes

NASA Astrophysics Data System (ADS)

Shectman, Stephen A.; Johns, Matthew

2003-02-01

Commissioning of the two 6.5-meter Magellan telescopes is nearing completion at the Las Campanas Observatory in Chile. The Magellan 1 primary mirror was successfully aluminized at Las Campanas in August 2000. Science operations at Magellan 1 began in February 2001. The second Nasmyth focus on Magellan 1 went into operation in September 2001. Science operations on Magellan 2 are scheduled to begin shortly. The ability to deliver high-quality images is maintained at all times by the simultaneous operation of the primary mirror support system, the primary mirror thermal control system, and a real-time active optics system, based on a Shack-Hartmann image analyzer. Residual aberrations in the delivered image (including focus) are typically 0.10-0.15" fwhm, and real images as good as 0.25" fwhm have been obtained at optical wavelengths. The mount points reliably to 2" rms over the entire sky, using a pointing model which is stable from year to year. The tracking error under typical wind conditions is better than 0.03" rms, although some degradation is observed under high wind conditions when the dome is pointed in an unfavorable direction. Instruments used at Magellan 1 during the first year of operation include two spectrographs previously used at other telescopes (B&C, LDSS-2), a mid-infrared imager (MIRAC) and an optical imager (MAGIC, the first Magellan-specific facility instrument). Two facility spectrographs are scheduled to be installed shortly: IMACS, a wide-field spectrograph, and MIKE, a double echelle spectrograph.

TIMED solar EUV experiment: preflight calibration results for the XUV photometer system

NASA Astrophysics Data System (ADS)

Woods, Thomas N.; Rodgers, Erica M.; Bailey, Scott M.; Eparvier, Francis G.; Ucker, Gregory J.

1999-10-01

The Solar EUV Experiment (SEE) on the NASA Thermosphere, Ionosphere, and Mesosphere Energetics and Dynamics (TIMED) mission will measure the solar vacuum ultraviolet (VUV) spectral irradiance from 0.1 to 200 nm. To cover this wide spectral range two different types of instruments are used: a grating spectrograph for spectra between 25 and 200 nm with a spectral resolution of 0.4 nm and a set of silicon soft x-ray (XUV) photodiodes with thin film filters as broadband photometers between 0.1 and 35 nm with individual bandpasses of about 5 nm. The grating spectrograph is called the EUV Grating Spectrograph (EGS), and it consists of a normal- incidence, concave diffraction grating used in a Rowland spectrograph configuration with a 64 X 1024 array CODACON detector. The primary calibrations for the EGS are done using the National Institute for Standards and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF-III) in Gaithersburg, Maryland. In addition, detector sensitivity and image quality, the grating scattered light, the grating higher order contributions, and the sun sensor field of view are characterized in the LASP calibration laboratory. The XUV photodiodes are called the XUV Photometer System (XPS), and the XPS includes 12 photodiodes with thin film filters deposited directly on the silicon photodiodes' top surface. The sensitivities of the XUV photodiodes are calibrated at both the NIST SURF-III and the Physikalisch-Technische Bundesanstalt (PTB) electron storage ring called BESSY. The other XPS calibrations, namely the electronics linearity and field of view maps, are performed in the LASP calibration laboratory. The XPS and solar sensor pre-flight calibration results are primarily discussed as the EGS calibrations at SURF-III have not yet been performed.

The infrared imaging spectrograph (IRIS) for TMT: overview of innovative science programs

NASA Astrophysics Data System (ADS)

Wright, Shelley A.; Larkin, James E.; Moore, Anna M.; Do, Tuan; Simard, Luc; Adamkovics, Maté; Armus, Lee; Barth, Aaron J.; Barton, Elizabeth; Boyce, Hope; Cooke, Jeffrey; Cote, Patrick; Davidge, Timothy; Ellerbroek, Brent; Ghez, Andrea M.; Liu, Michael C.; Lu, Jessica R.; Macintosh, Bruce A.; Mao, Shude; Marois, Christian; Schoeck, Matthias; Suzuki, Ryuji; Tan, Jonathan C.; Treu, Tommaso; Wang, Lianqi; Weiss, Jason

2014-07-01

IRIS (InfraRed Imaging Spectrograph) is a first light near-infrared diffraction limited imager and integral field spectrograph being designed for the future Thirty Meter Telescope (TMT). IRIS is optimized to perform astronomical studies across a significant fraction of cosmic time, from our Solar System to distant newly formed galaxies (Barton et al. [1]). We present a selection of the innovative science cases that are unique to IRIS in the era of upcoming space and ground-based telescopes. We focus on integral field spectroscopy of directly imaged exoplanet atmospheres, probing fundamental physics in the Galactic Center, measuring 104 to 1010 M supermassive black hole masses, resolved spectroscopy of young star-forming galaxies (1 < z < 5) and first light galaxies (6 < z < 12), and resolved spectroscopy of strong gravitational lensed sources to measure dark matter substructure. For each of these science cases we use the IRIS simulator (Wright et al. [2], Do et al. [3]) to explore IRIS capabilities. To highlight the unique IRIS capabilities, we also update the point and resolved source sensitivities for the integral field spectrograph (IFS) in all five broadband filters (Z, Y, J, H, K) for the finest spatial scale of 0.004" per spaxel. We briefly discuss future development plans for the data reduction pipeline and quicklook software for the IRIS instrument suite.

[Design and analysis of a novel light visible spectrum imaging spectrograph optical system].

PubMed

Shen, Man-de; Li, Fei; Zhou, Li-bing; Li, Cheng; Ren, Huan-huan; Jiang, Qing-xiu

2015-02-01

A novel visible spectrum imaging spectrograph optical system was proposed based on the negative dispersion, the arbitrary phase modulation characteristics of diffractive optical element and the aberration correction characteristics of freeform optical element. The double agglutination lens was substituted by a hybrid refractive/diffractive lens based on the negative dispersion of diffractive optical element. Two freeform optical elements were used in order to correct some aberration based on the aberration correction characteristics of freeform optical element. An example and frondose design process were presented. When the design parameters were uniform, compared with the traditional system, the novel visible spectrum imaging spectrograph optical system's weight was reduced by 22.9%, the total length was reduced by 26.6%, the maximal diameter was reduced by 30.6%, and the modulation transfer function (MTF) in 1.0 field-of-view was improved by 0.35 with field-of-view improved maximally. The maximal distortion was reduced by 1.6%, the maximal longitudinal aberration was reduced by 56.4%, and the lateral color aberration was reduced by 59. 3%. From these data, we know that the performance of the novel system was advanced quickly and it could be used to put forward a new idea for modern visible spectrum imaging spectrograph optical system design.

MicroRaman Spectroscopy and Raman Imaging of Basal Cell Carcinoma

NASA Astrophysics Data System (ADS)

Short, M. A.; Zeng, H.; Lui, H.

2005-03-01

We have measured the Raman spectra of normal and cancerous skin tissues using a confocal microRaman spectrograph with a sub-micron spatial resolution. We found that the Raman spectrum of a cell nucleolus is different from the spectra measured outside the nucleolus and considerably different from those measured outside the nucleus. In addition, we found significant spectroscopic differences between normal and cancer-bearing sites in the dermis region. In order to utilize these differences for non-invasive skin cancer diagnosis, we have developed a Raman imaging system that clearly demonstrates the structure, location and distribution of cells in unstained skin biopsy samples. Our method is expected to be useful for the detection and characterization of skin cancer based on the known distinct cellular differences between normal and malignant skin.

A LWIR hyperspectral imager using a Sagnac interferometer and cooled HgCdTe detector array

NASA Astrophysics Data System (ADS)

Lucey, Paul G.; Wood, Mark; Crites, Sarah T.; Akagi, Jason

2012-06-01

LWIR hyperspectral imaging has a wide range of civil and military applications with its ability to sense chemical compositions at standoff ranges. Most recent implementations of this technology use spectrographs employing varying degrees of cryogenic cooling to reduce sensor self-emission that can severely limit sensitivity. We have taken an interferometric approach that promises to reduce the need for cooling while preserving high resolution. Reduced cooling has multiple benefits including faster system readiness from a power off state, lower mass, and potentially lower cost owing to lower system complexity. We coupled an uncooled Sagnac interferometer with a 256x320 mercury cadmium telluride array with an 11 micron cutoff to produce a spatial interferometric LWIR hyperspectral imaging system operating from 7.5 to 11 microns. The sensor was tested in ground-ground applications, and from a small aircraft producing spectral imagery including detection of gas emission from high vapor pressure liquids.

GRACES, the Gemini remote access CFHT ESPaDOnS spectrograph: initial design and testing

NASA Astrophysics Data System (ADS)

Tollestrup, Eric V.; Pazder, John; Barrick, Gregory; Martioli, Eder; Schiavon, Ricardo; Anthony, André; Halman, Mark; Veillet, Christian

2012-09-01

The Gemini Remote Access CFHT ESPaDOnS Spectrograph (GRACES) is an innovative instrumentation experiment that will demonstrate if ESPaDOnS, a bench-mounted high-resolution optical spectrograph at CFHT, can be fed by a 270-m long fiber from the Gemini-North telescope with low enough losses to remain competitive with conventional spectrographs on other 8 to 10-m telescopes. Detailed simulations have shown that GRACES should be more sensitive than the HIRES spectrograph at Keck Observatory at wavelengths longer than about 600-700 nm. This result is possible by using FPB-type of optical fibers made by Polymicro Technologies and by keeping the critical focal ratio degradation (FRD) losses to less than 10%. Laboratory tests on these FPB optical fibers are underway and show that for 36-m lengths that the FRD losses are as low as 0.8% with a repeatability of 1%. Tests are currently underway on 280-m lengths.

HESP: Instrument control, calibration and pipeline development

NASA Astrophysics Data System (ADS)

Anantha, Ch.; Roy, Jayashree; Mahesh, P. K.; Parihar, P. S.; Sangal, A. K.; Sriram, S.; Anand, M. N.; Anupama, G. C.; Giridhar, S.; Prabhu, T. P.; Sivarani, T.; Sundararajan, M. S.

Hanle Echelle SPectrograph (HESP) is a fibre-fed, high resolution (R = 30,000 and 60,000) spectrograph being developed for the 2m HCT telescope at IAO, Hanle. The major components of the instrument are a) Cassegrain unit b) Spectrometer instrument. An instrument control system interacting with a guiding unit at Cassegrain interface as well as handling spectrograph functions is being developed. An on-axis auto-guiding using the spill-over angular ring around the input pinhole is also being developed. The stellar light from the Cassegrain unit is taken to the spectrograph using an optical fiber which is being characterized for spectral transmission, focal ratio degradation and scrambling properties. The design of the thermal enclosure and thermal control for the spectrograph housing is presented. A data pipeline for the entire Echelle spectral reduction is being developed. We also plan to implement an instrument physical model based calibration into the main data pipeline and in the maintenance and quality control operations.

CUBES: cassegrain U-band Brazil-ESO spectrograph

NASA Astrophysics Data System (ADS)

Barbuy, B.; Bawden Macanhan, V.; Bristow, P.; Castilho, B.; Dekker, H.; Delabre, B.; Diaz, M.; Gneiding, C.; Kerber, F.; Kuntschner, H.; La Mura, G.; Maciel, W.; Meléndez, J.; Pasquini, L.; Pereira, C. B.; Petitjean, P.; Reiss, R.; Siqueira-Mello, C.; Smiljanic, R.; Vernet, J.

2014-11-01

CUBES is a high-efficiency, medium-resolution ( R˜20,000) ground based UV (300-400 nm) spectrograph, to be installed in the cassegrain focus of one of ESO's VLT unit telescopes in 2017/18. The CUBES project is a joint venture between ESO and IAG/USP, and LNA/MCTI. CUBES will provide access to a wealth of new and relevant information for stellar as well as extragalactic sources. Main science cases include the study of beryllium and heavy elements in metal-poor stars, the direct determination of carbon, nitrogen and oxygen abundances by study of molecular bands in the UV range, as well as the study of active galactic nuclei and the quasar absorption lines. With a streamlined modern instrument design, high efficiency dispersing elements and UV-sensitive detectors, it will give a significant gain in sensitivity over existing ground based medium-high resolution spectrographs, enabling vastly increased sample sizes accessible to the astronomical community. We present here a brief overview of the project including the status, science cases and a discussion of the design options.

MEGARA: large pupil element tests and performance

NASA Astrophysics Data System (ADS)

Martínez-Delgado, I.; Sánchez-Blanco, E.; Pérez-Calpena, A.; García-Vargas, M. L.; Maldonado, X. M.; Gil de Paz, A.; Carrasco, E.; Gallego, J.; Iglesias-Páramo, J.; Sánchez-Moreno, F. M.

2016-07-01

MEGARA is a third generation spectrograph for the Spanish 10.4m telescope (GTC) providing two observing modes: a large central Integral Field Unit (IFU), called the Large Compact Bundle (LCB), covering a FOV of 12.5 × 11.3 arcsec2, and a Multi-Object Spectrograph (MOS) with a FOV of 3.5 × 3.5 arcmin2. MEGARA will observe the whole visible range from 3650A to 10000A allowing different spectral resolutions (low, medium and high) with R = 6000, 11000 and 18000 respectively. The dispersive elements are placed at the spectrograph pupil position in the path of the collimated beam and they are composed of a set of volume phase hologram gratings (VPHs) sandwiched between two flat windows and coupled in addition to two prisms in the case of the medium- and high-resolution units. We will describe the tests and setups developed to check the requirements of all units, as well as the obtained performance at laboratory

VizieR Online Data Catalog: Accurate astrometry & RVs of 4 multiple systems (Tokovinin+, 2017)

NASA Astrophysics Data System (ADS)

Tokovinin, A.; Latham, D. W.

2017-10-01

The outer subsystems are classical visual binaries. Historic micrometric measurements and modern speckle interferometric data have been obtained from the WDS database on our request. Additionally, we secured new speckle astrometry and relative photometry of two systems at the 4.1m SOAR telescope. Published radial velocities (RVs) are used here together with the new data. The RVs were measured with the CfA Digital Speedometers, initially using the 1.5m Wyeth Reflector at the Oak Ridge Observatory in the town of Harvard, Massachusetts, and subsequently with the 1.5m Tillinghast Reflector at the Whipple Observatory on Mount Hopkins, Arizona. Starting in 2009, the new fiber-fed Tillinghast Reflector Echelle Spectrograph (TRES) was used. The spectral resolution was 44000 for all three spectrographs. Two objects, HIP 101955 and 103987, were observed in 2015 with the CHIRON echelle spectrograph at the 1.5m telescope at CTIO with a spectral resolution of 80000. (4 data files).

Deployment of the Hobby-Eberly Telescope wide-field upgrade

NASA Astrophysics Data System (ADS)

Hill, Gary J.; Drory, Niv; Good, John M.; Lee, Hanshin; Vattiat, Brian L.; Kriel, Herman; Ramsey, Jason; Bryant, Randy; Elliot, Linda; Fowler, Jim; Häuser, Marco; Landiau, Martin; Leck, Ron; Odewahn, Stephen; Perry, Dave; Savage, Richard; Schroeder Mrozinski, Emily; Shetrone, Matthew; DePoy, D. L.; Prochaska, Travis; Marshall, J. L.; Damm, George; Gebhardt, Karl; MacQueen, Phillip J.; Martin, Jerry; Armandroff, Taft; Ramsey, Lawrence W.

2016-07-01

The Hobby-Eberly Telescope (HET) is an innovative large telescope, located in West Texas at the McDonald Observatory. The HET operates with a fixed segmented primary and has a tracker, which moves the four-mirror corrector and prime focus instrument package to track the sidereal and non-sidereal motions of objects. We have completed a major multi-year upgrade of the HET that has substantially increased the pupil size to 10 meters and the field of view to 22 arcminutes by replacing the corrector, tracker, and prime focus instrument package. The new wide field HET will feed the revolutionary integral field spectrograph called VIRUS, in support of the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX§), a new low resolution spectrograph (LRS2), an upgraded high resolution spectrograph (HRS2), and later the Habitable Zone Planet Finder (HPF). The upgrade is being commissioned and this paper discusses the completion of the installation, the commissioning process and the performance of the new HET.

FIEStool: Automated data reduction for FIber-fed Echelle Spectrograph (FIES)

NASA Astrophysics Data System (ADS)

Stempels, Eric; Telting, John

2017-08-01

FIEStool automatically reduces data obtained with the FIber-fed Echelle Spectrograph (FIES) at the Nordic Optical Telescope, a high-resolution spectrograph available on a stand-by basis, while also allowing the basic properties of the reduction to be controlled in real time by the user. It provides a Graphical User Interface and offers bias subtraction, flat-fielding, scattered-light subtraction, and specialized reduction tasks from the external packages IRAF (ascl:9911.002) and NumArray. The core of FIEStool is instrument-independent; the software, written in Python, could with minor modifications also be used for automatic reduction of data from other instruments.

TAIPAN fibre feed and spectrograph: engineering overview

NASA Astrophysics Data System (ADS)

Staszak, Nicholas F.; Lawrence, Jon; Zhelem, Ross; Content, Robert; Churilov, Vladimir; Case, Scott; Brown, Rebecca; Hopkins, Andrew M.; Kuehn, Kyler; Pai, Naveen; Klauser, Urs; Nichani, Vijay; Waller, Lew

2016-07-01

TAIPAN will conduct a stellar and galaxy survey of the Southern sky. The TAIPAN positioner is being developed as a prototype for the MANIFEST instrument on the GMT. The TAIPAN Spectrograph is an AAO designed all-refractive 2-arm design that delivers a spectral resolution of R>2000 over the wavelength range 370-870 nm. It is fed by a custom fibre cable from the TAIPAN Starbugs positioner. The design for TAIPAN incorporates 150 optical fibres (with an upgrade path to 300). Presented is an engineering overview of the UKST Fibre Cable design used to support Starbugs, the custom slit design, and the overall design and build plan for the TAIPAN Spectrograph.

Rise to SUMMIT: the Sydney University Multiple-Mirror Telescope

NASA Astrophysics Data System (ADS)

Moore, Anna M.; Davis, John

2000-07-01

The Sydney University Multiple Mirror Telescope (SUMMIT) is a medium-sized telescope designed specifically for high resolution stellar spectroscopy. Throughout the design emphasis has been placed on high efficiency at low cost. The telescope consists of four 0.46 m diameter mirrors mounted on a single welded steel frame. Specially designed mirror cells support and point each mirror, allowing accurate positioning of the images on optical fibers located at the foci of the mirrors. Four fibers convey the light to the future location of a high resolution spectrograph away from the telescope in a stable environment. An overview of the commissioning of the telescope is presented, including the guidance and automatic mirror alignment and focussing systems. SUMMIT is located alongside the Sydney University Stellar Interferometer at the Paul Wild Observatory, near Narrabri, Northern New South Wales.

Iranian National Observatory

NASA Astrophysics Data System (ADS)

Khosroshahi, H. G.; Danesh, A.; Molaeinezhad, A.

2016-09-01

The Iranian National Observatory is under construction at an altitude of 3600m at Gargash summit 300km southern Tehran. The site selection was concluded in 2007 and the site monitoring activities have begun since then, which indicates a high quality of the site with a median seeing of 0.7 arcsec through the year. One of the major observing facilities of the observatory is a 3.4m Alt-Az Ritchey-Chretien optical telescope which is currently under design. This f/11 telescope will be equipped with high resolution medium-wide field imaging cameras as well as medium and high resolution spectrographs. In this review, I will give an overview of astronomy research and education in Iran. Then I will go through the past and present activities of the Iranian National Observatory project including the site quality, telescope specifications and instrument capabilities.

General Astrophysics Science Enabled by the HabEx Ultraviolet Spectrograph (UVS)

NASA Astrophysics Data System (ADS)

Scowen, Paul; Clarke, John; Gaudi, B. Scott; Kiessling, Alina; Martin, Stefan; Somerville, Rachel; Stern, Daniel; HabEx Science and Technology Definition Team

2018-01-01

The Habitable Exoplanet Imaging Mission (HabEx) is one of the four large mission concepts being studied by NASA as input to the upcoming 2020 Decadal Survey. The mission implements two world-class General Astrophysics instruments as part of its complement of instrumentation to enable compelling science using the 4m aperture. The Ultraviolet Spectrograph has been designed to address cutting edge far ultraviolet (FUV) science that has not been possible with the Hubble Space Telescope, and to open up a wide range of capabilities that will advance astrophysics as we look into the 2030s. Our poster discusses some of those science drivers and possible applications, which range from Solar System science, to nearby and more distant studies of star formation, to studies of the circumgalactic and intergalactic mediums where the ecology of mass and energy transfer are vital to understanding stellar and galactic evolution. We discuss the performance features of the instrument that include a large 3’x3’ field of view for multi-object spectroscopy, and some 20 grating modes for a variety of spectral resolution and coverage.

The NASA probe-class mission concept, CETUS (Cosmic Evolution Through Ultraviolet Spectroscopy)

NASA Astrophysics Data System (ADS)

Heap, Sara; Danchi, William; Burge, James; Dodson, Kelly; Hull, Anthony; Kendrick, Steven; McCandliss, Stephan; Mehle, Gregory; Purves, Lloyd; Sheikh, David; Valente, Martin; Woodruff, Robert A.

2017-09-01

We report on the early phases of a NASA-sponsored study of CETUS (Cosmic Evolution Through Ultraviolet Spectroscopy), a Probe-class mission concept. By definition, the full lifecycle cost of a Probe mission is greater than 400M (i.e. Explorer missions) and less than 1.00B ("Flagship" missions). The animating idea behind our study is that CETUS can help answer fundamental questions about galaxy evolution by carrying out a massive UV imaging and spectroscopic survey of galaxies and combining its findings with data obtained by other survey telescopes of the 2020's. The CETUS mission concept comprises a 1.5-m wide-field telescope and three scientific instruments: a near-UV multi-object slit spectrograph with a micro-shutter array as the slit device; a near-UV and far-UV camera with angular resolution of 0.42" (near-UV) or 0.55" (far-UV); and a near-UV or far-UV single-object spectrograph aimed at providing access to the UV after Hubble is gone. We describe the scientific rationale for CETUS and the telescope and instruments in their early design phase.

Realizing software longevity over a system's lifetime

NASA Astrophysics Data System (ADS)

Lanclos, Kyle; Deich, William T. S.; Kibrick, Robert I.; Allen, Steven L.; Gates, John

2010-07-01

A successful instrument or telescope will measure its productive lifetime in decades; over that period, the technology behind the control hardware and software will evolve, and be replaced on a per-component basis. These new components must successfully integrate with the old, and the difficulty of that integration depends strongly on the design decisions made over the course of the facility's history. The same decisions impact the ultimate success of each upgrade, as measured in terms of observing efficiency and maintenance cost. We offer a case study of these critical design decisions, analyzing the layers of software deployed for instruments under the care of UCO/Lick Observatory, including recent upgrades to the Low Resolution Imaging Spectrometer (LRIS) at Keck Observatory in Hawaii, as well as the Kast spectrograph, Lick Adaptive Optics system, and Hamilton spectrograph, all at Lick Observatory's Shane 3-meter Telescope at Mt. Hamilton. These issues play directly into design considerations for the software intended for use at the next generation of telescopes, such as the Thirty Meter Telescope. We conduct our analysis with the future of observational astronomy infrastructure firmly in mind.

MuSICa: the Multi-Slit Image Slicer for the est Spectrograph

NASA Astrophysics Data System (ADS)

Calcines, A.; López, R. L.; Collados, M.

2013-09-01

Integral field spectroscopy (IFS) is a technique that allows one to obtain the spectra of all the points of a bidimensional field of view simultaneously. It is being applied to the new generation of the largest night-time telescopes but it is also an innovative technique for solar physics. This paper presents the design of a new image slicer, MuSICa (Multi-Slit Image slicer based on collimator-Camera), for the integral field spectrograph of the 4-m aperture European Solar Telescope (EST). MuSICa is a multi-slit image slicer that decomposes an 80 arcsec2 field of view into slices of 50 μm and reorganizes it into eight slits of 0.05 arcsec width × 200 arcsec length. It is a telecentric system with an optical quality at diffraction limit compatible with the two modes of operation of the spectrograph: spectroscopic and spectro-polarimetric. This paper shows the requirements, technical characteristics and layout of MuSICa, as well as other studied design options.

The infrared imaging spectrograph (IRIS) for TMT: latest science cases and simulations

NASA Astrophysics Data System (ADS)

Wright, Shelley A.; Walth, Gregory; Do, Tuan; Marshall, Daniel; Larkin, James E.; Moore, Anna M.; Adamkovics, Mate; Andersen, David; Armus, Lee; Barth, Aaron; Cote, Patrick; Cooke, Jeff; Chisholm, Eric M.; Davidge, Timothy; Dunn, Jennifer S.; Dumas, Christophe; Ellerbroek, Brent L.; Ghez, Andrea M.; Hao, Lei; Hayano, Yutaka; Liu, Michael; Lopez-Rodriguez, Enrique; Lu, Jessica R.; Mao, Shude; Marois, Christian; Pandey, Shashi B.; Phillips, Andrew C.; Schoeck, Matthias; Subramaniam, Annapurni; Subramanian, Smitha; Suzuki, Ryuji; Tan, Jonathan C.; Terai, Tsuyoshi; Treu, Tommaso; Simard, Luc; Weiss, Jason L.; Wincentsen, James; Wong, Michael; Zhang, Kai

2016-07-01

The Thirty Meter Telescope (TMT) first light instrument IRIS (Infrared Imaging Spectrograph) will complete its preliminary design phase in 2016. The IRIS instrument design includes a near-infrared (0.85 - 2.4 micron) integral field spectrograph (IFS) and imager that are able to conduct simultaneous diffraction-limited observations behind the advanced adaptive optics system NFIRAOS. The IRIS science cases have continued to be developed and new science studies have been investigated to aid in technical performance and design requirements. In this development phase, the IRIS science team has paid particular attention to the selection of filters, gratings, sensitivities of the entire system, and science cases that will benefit from the parallel mode of the IFS and imaging camera. We present new science cases for IRIS using the latest end-to-end data simulator on the following topics: Solar System bodies, the Galactic center, active galactic nuclei (AGN), and distant gravitationally-lensed galaxies. We then briefly discuss the necessity of an advanced data management system and data reduction pipeline.

Spectroscopic classification of PS17chm with Double Spectrograph on Palomar 200-inch telescope

NASA Astrophysics Data System (ADS)

Blagorodnova, N.; Kupfer, T.; Burdge, K.; Kasliwal, M.; Adams, S.

2017-04-01

We report the classification of PS17chm, discovered by the by the Pan-STARRS Survey for Transients (see Chambers et al. 2016, arXiv:1612.05560, and http://pswww.ifa.hawaii.edu ). The observations were performed on UT 2017-04-19 with the Double Spectrograph (DBSP; range 350-1000nm, spectral resolution R 4000) on Palomar 200-inch (P200) telescope.

GIANO and HARPS-N together: towards an Earth-mass detection instrument

NASA Astrophysics Data System (ADS)

Tozzi, A.; Oliva, E.; Iuzzolino, M.; Fini, L.; Puglisi, A.; Sozzi, M.; Falcini, G.; Carbonaro, L.; Ghedina, A.; Mercatelli, L.; Seemann, U.; Claudi, R.

2016-08-01

This article describes the works we are doing for modifying the interface between the high resolution infrared spectrograph GIANO (0.97-2.4 micron) and the TNG telescope, passing from a fiber feed configuration to the original design of a direct light-feeding from the telescope to the spectrograph. So doing the IR spectrograph, GIANO, will work in parallel to HARPS-N spectrometer (0.38-0.70 micron), the visible high resolution spectrograph, thanks to a new telescope interface based on a dichroic window that simultaneously feeds the two instrumentes: this is GIARPS (GIAno and haRPS). The scientific aims of this project are to improve the radial velocity accuracy achievable with GIANO, down to a goal of 1 m/s, the value necessary to detect Earth-mass planets on habitable orbits around late-M stars, to implement simultaneous observations with Harps-N and GIANO optimizing the study of planets around cool stars. The very broad wavelengths range is particularly important to discriminate false radial velocity signals caused by stellar activity. We therefore include several absorption cells with different mixtures of gases and a stabilized Fabry Perot cavity, necessary to have absorption lines over the 0.97-2.4 microns range covered by GIANO. The commissioning of GIARPS is scheduled by the end of 2016.

Explosive Events in the Quiet Sun: Extreme Ultraviolet Imaging Spectroscopy Instrumentation and Observations

NASA Astrophysics Data System (ADS)

Rust, Thomas Ludwell

Explosive event is the name given to slit spectrograph observations of high spectroscopic velocities in solar transition region spectral lines. Explosive events show much variety that cannot yet be explained by a single theory. It is commonly believed that explosive events are powered by magnetic reconnection. The evolution of the line core appears to be an important indicator of which particular reconnection process is at work. The Multi-Order Solar Extreme Ultraviolet Spectrograph (MOSES) is a novel slitless spectrograph designed for imaging spectroscopy of solar extreme ultraviolet (EUV) spectral lines. The spectrograph design forgoes a slit and images instead at three spectral orders of a concave grating. The images are formed simultaneously so the resulting spatial and spectral information is co-temporal over the 20' x 10' instrument field of view. This is an advantage over slit spectrographs which build a field of view one narrow slit at a time. The cost of co-temporal imaging spectroscopy with the MOSES is increased data complexity relative to slit spectrograph data. The MOSES data must undergo tomographic inversion for recovery of line profiles. I use the unique data from the MOSES to study transition region explosive events in the He ii 304 A spectral line. I identify 41 examples of explosive events which include 5 blue shifted jets, 2 red shifted jets, and 10 bi-directional jets. Typical doppler speeds are approximately 100kms-1. I show the early development of one blue jet and one bi-directional jet and find no acceleration phase at the onset of the event. The bi-directional jets are interesting because they are predicted in models of Petschek reconnection in the transition region. I develop an inversion algorithm for the MOSES data and test it on synthetic observations of a bi-directional jet. The inversion is based on a multiplicative algebraic reconstruction technique (MART). The inversion successfully reproduces synthetic line profiles. I then use the inversion to study the time evolution of a bi-directional jet. The inverted line profiles show fast doppler shifted components and no measurable line core emission. The blue and red wings of the jet show increasing spatial separation with time.

Toroidal varied-line space (TVLS) gratings

NASA Astrophysics Data System (ADS)

Thomas, Roger J.

2003-02-01

It is a particular challenge to develop a stigmatic spectrograph for EUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both re-imaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-space rulings (TULS). A number of solar EUV spectrographs have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets SERTS and EUNIS. More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. These ideas are now combined into a spectrograph concept that considers varied-line space grooves ruled onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of two solar spectrographs based on this concept are described: SUMI, proposed as a sounding rocket experiment, and NEXUS, proposed for the Solar Dynamics Observatory mission.

Rocket instrument for far-UV spectrophotometry of faint astronomical objects.

PubMed

Hartig, G F; Fastie, W G; Davidsen, A F

1980-03-01

A sensitive sounding rocket instrument for moderate (~10-A) resolution far-UV (lambda1160-lambda1750-A) spectrophotometry of faint astronomical objects has been developed. The instrument employs a photon-counting microchannel plate imaging detector and a concave grating spectrograph behind a 40-cm Dall-Kirkham telescope. A unique remote-control pointing system, incorporating an SIT vidicon aspect camera, two star trackers, and a tone-encoded command telemetry link, permits the telescope to be oriented to within 5 arc sec of any target for which suitable guide stars can be found. The design, construction, calibration, and flight performance of the instrument are discussed.

Stellar Oscillations Network Group

NASA Astrophysics Data System (ADS)

Grundahl, F.; Kjeldsen, H.; Christensen-Dalsgaard, J.; Arentoft, T.; Frandsen, S.

2007-06-01

Stellar Oscillations Network Group (SONG) is an initiative aimed at designing and building a network of 1m-class telescopes dedicated to asteroseismology and planet hunting. SONG will have 8 identical telescope nodes each equipped with a high-resolution spectrograph and an iodine cell for obtaining precision radial velocities and a CCD camera for guiding and imaging purposes. The main asteroseismology targets for the network are the brightest (V < 6) stars. In order to improve performance and reduce maintenance costs the instrumentation will only have very few modes of operation. In this contribution we describe the motivations for establishing a network, the basic outline of SONG and the expected performance.

First light of the Gemini Planet Imager

PubMed Central

Macintosh, Bruce; Graham, James R.; Ingraham, Patrick; Konopacky, Quinn; Marois, Christian; Perrin, Marshall; Poyneer, Lisa; Bauman, Brian; Barman, Travis; Burrows, Adam S.; Cardwell, Andrew; Chilcote, Jeffrey; De Rosa, Robert J.; Dillon, Daren; Doyon, Rene; Dunn, Jennifer; Erikson, Darren; Fitzgerald, Michael P.; Gavel, Donald; Goodsell, Stephen; Hartung, Markus; Hibon, Pascale; Kalas, Paul; Larkin, James; Maire, Jerome; Marchis, Franck; Marley, Mark S.; McBride, James; Millar-Blanchaer, Max; Morzinski, Katie; Norton, Andrew; Oppenheimer, B. R.; Palmer, David; Patience, Jennifer; Pueyo, Laurent; Rantakyro, Fredrik; Sadakuni, Naru; Saddlemyer, Leslie; Savransky, Dmitry; Serio, Andrew; Soummer, Remi; Sivaramakrishnan, Anand; Song, Inseok; Thomas, Sandrine; Wallace, J. Kent; Wiktorowicz, Sloane; Wolff, Schuyler

2014-01-01

The Gemini Planet Imager is a dedicated facility for directly imaging and spectroscopically characterizing extrasolar planets. It combines a very high-order adaptive optics system, a diffraction-suppressing coronagraph, and an integral field spectrograph with low spectral resolution but high spatial resolution. Every aspect of the Gemini Planet Imager has been tuned for maximum sensitivity to faint planets near bright stars. During first-light observations, we achieved an estimated H band Strehl ratio of 0.89 and a 5-σ contrast of 106 at 0.75 arcseconds and 105 at 0.35 arcseconds. Observations of Beta Pictoris clearly detect the planet, Beta Pictoris b, in a single 60-s exposure with minimal postprocessing. Beta Pictoris b is observed at a separation of 434 ± 6 milliarcseconds (mas) and position angle 211.8 ± 0.5°. Fitting the Keplerian orbit of Beta Pic b using the new position together with previous astrometry gives a factor of 3 improvement in most parameters over previous solutions. The planet orbits at a semimajor axis of 9.0−0.4+0.8 AU near the 3:2 resonance with the previously known 6-AU asteroidal belt and is aligned with the inner warped disk. The observations give a 4% probability of a transit of the planet in late 2017. PMID:24821792

First light of the Gemini Planet imager.

PubMed

Macintosh, Bruce; Graham, James R; Ingraham, Patrick; Konopacky, Quinn; Marois, Christian; Perrin, Marshall; Poyneer, Lisa; Bauman, Brian; Barman, Travis; Burrows, Adam S; Cardwell, Andrew; Chilcote, Jeffrey; De Rosa, Robert J; Dillon, Daren; Doyon, Rene; Dunn, Jennifer; Erikson, Darren; Fitzgerald, Michael P; Gavel, Donald; Goodsell, Stephen; Hartung, Markus; Hibon, Pascale; Kalas, Paul; Larkin, James; Maire, Jerome; Marchis, Franck; Marley, Mark S; McBride, James; Millar-Blanchaer, Max; Morzinski, Katie; Norton, Andrew; Oppenheimer, B R; Palmer, David; Patience, Jennifer; Pueyo, Laurent; Rantakyro, Fredrik; Sadakuni, Naru; Saddlemyer, Leslie; Savransky, Dmitry; Serio, Andrew; Soummer, Remi; Sivaramakrishnan, Anand; Song, Inseok; Thomas, Sandrine; Wallace, J Kent; Wiktorowicz, Sloane; Wolff, Schuyler

2014-09-02

The Gemini Planet Imager is a dedicated facility for directly imaging and spectroscopically characterizing extrasolar planets. It combines a very high-order adaptive optics system, a diffraction-suppressing coronagraph, and an integral field spectrograph with low spectral resolution but high spatial resolution. Every aspect of the Gemini Planet Imager has been tuned for maximum sensitivity to faint planets near bright stars. During first-light observations, we achieved an estimated H band Strehl ratio of 0.89 and a 5-σ contrast of 10(6) at 0.75 arcseconds and 10(5) at 0.35 arcseconds. Observations of Beta Pictoris clearly detect the planet, Beta Pictoris b, in a single 60-s exposure with minimal postprocessing. Beta Pictoris b is observed at a separation of 434 ± 6 milliarcseconds (mas) and position angle 211.8 ± 0.5°. Fitting the Keplerian orbit of Beta Pic b using the new position together with previous astrometry gives a factor of 3 improvement in most parameters over previous solutions. The planet orbits at a semimajor axis of [Formula: see text] near the 3:2 resonance with the previously known 6-AU asteroidal belt and is aligned with the inner warped disk. The observations give a 4% probability of a transit of the planet in late 2017.

First results from the Goddard High-Resolution spectrograph - High-resolution observations of the 1942 A resonance line of HG II in the chemically peculiar B star, Chi Lupi

NASA Technical Reports Server (NTRS)

Leckrone, David S.; Wahlgren, Glenn M.; Johansson, Sveneric G.

1991-01-01

The Goddard High-Resolution Spectrograph on the HST has been used to obtain high S/N observations of the sharp-lined, Hg- and Pt-rich B-type star, Chi Lupi, with a resolving power of 87,000. The observations reveal a level of spectroscopic detail never before observed at ultraviolet wavelengths for any star other than the sun. Concentrating on the region around the resonance line of Hg II at 1942 A, the profile and central position of this line confirm beyond doubt that the Hg isotope anomaly in Chi Lupi is real and extreme, with Hg being heavily concentrated in the form of Hg-204. The problems in atomic physics which impair the accurate analysis of spectra of this quality are emphasized.

Thirty-Meter Telescope: A Technical Study of the InfraRed Multiobject Spectrograph

NASA Astrophysics Data System (ADS)

U, Vivian; Dekany, R.; Mobasher, B.

2013-01-01

The InfraRed Multiobject Spectrograph (IRMS) is an adaptive optics (AO)-fed, reconfigurable near-infrared multi-object spectrograph and imager on the Thirty Meter Telescope (TMT). Its design is based on the MOSFIRE spectrograph currently operating on the Keck Observatory. As one of the first three first-light instruments on the TMT, IRMS is in a mini-conceptual design phase. Here we motivate the science goals of the instrument and present the anticipated sensitivity estimates based on the combination of MOSFIRE with the AO system NFIRAOS on TMT. An assessment of the IRMS on-instrument wavefront sensor performance and vignetting issue will also be discussed.

SpS1-SOFIA studies of stellar evolution

NASA Astrophysics Data System (ADS)

Gehrz, R. D.; Becklin, E. E.; Roellig, T. L.

2010-11-01

The U.S./German Stratospheric Observatory for Infrared Astronomy (SOFIA, Figure 1) is a 2.5-meter infrared airborne telescope in a Boeing 747-SP flying in the stratosphere at altitudes as high as 45,000 feet where the atmospheric transmission averages ≥ 80% throughout the 0.3 - 1600 μm spectral region. SOFIA's first-generation instruments include broadband imagers, moderate resolution spectrographs capable of resolving broad features due to dust and large molecules, and high resolution spectrometers suitable for kinematic studies of molecular and atomic gas lines at km s-1 resolution. These and future instruments will enable SOFIA to make unique contributions to studies of the physics and chemistry of stellar evolution for many decades. Science flights will begin in 2010. A full operations schedule of at least 100 flights per year will begin in 2014 and will continue for 20 years. The SOFIA Guest Investigator (GI) program, open to investigators worldwide, will constitute the major portion of the SOFIA observing program.

First light of a laser frequency comb at SALT

NASA Astrophysics Data System (ADS)

Depagne, Éric; McCracken, Richard A.; Reid, Derryck T.; Kuhn, Rudi B.; Erasmus, Nicolas; Crause, Lisa A.

2016-08-01

We present preliminary results of the commissioning and testing of SALT-CRISP (SALT-Calibration Ruler for Increased Spectrograph Precision), a Laser Frequency Comb (LFC) built by Heriot-Watt University and temporarily installed at the Southern African Large Telescope (SALT). The comb feeds the High Stability mode of SALT's High Resolution Spectrograph (HRS) and fully covers the wavelength range of the red channel of the HRS: 555-890 nm. The LFC provides significantly improved wavelength calibration compared to a standard Thorium-Argon (ThAr) lamp and hence offers unprecedented opportunities to characterise the resolution, stability and radial velocity precision of the HRS. Results from this field trial will be incorporated into subsequent LFC designs.

Compact optics for high resolution spectroscopy of celestial x-ray sources

NASA Astrophysics Data System (ADS)

Cash, W.; Lillie, C.; McEntaffer, R.; Zhang, W.

2011-05-01

The astronomy community has never flown a celestial source spectrograph that can resolve natural line widths in absorption the way the ultraviolet community since OAO-3 Copernicus in 1972. Yet there is important science to be mined there, and right now there are now missions on track to pursue it. We present a modified off-plane grating spectrograph design that will support high resolution (λ/δλ ~ 4000) in the soft x-ray band with a high packing density that will enable a modest cost space mission. We discuss the design for the WHIMEx mission which was proposed as an Explorer earlier this year with the goal of detecting high temperature oxygen in the Intergalactic Medium.

Hubble illuminates the universe

NASA Technical Reports Server (NTRS)

Maran, Stephen P.

1992-01-01

Latest observations by the Hubble Space Telescope (HST) are described, including the first 'parallel' observations (on January 6, 1992) by the two of the Hubble's instruments of two different targets at the same time. On this date, the faint-object camera made images of the quasar 3C 273 in Virgo, while the wide-field and planetary camera recorded an adjacent field. The new HST images include those of the nucleus and the jet of M85, the giant elliptical galaxy at the heart of the Virgo cluster, and what appears to be a black hole of mass 2.6 billion solar masses in M87, and an image of N66, a planetary nebula in the LMC. Other images yield evidence of 'blue stragglers' in the core of 47 Tucanae, a globular cluster about 16,000 light-years from earth. The Goddard spectrograph recorded the spectrum of the star Capella at very high wavelength resolution, which made it possible to measure deuterium from the Big Bang.

Coral reef monitoring by the compact airborne spectrographic imager (CASI)

NASA Astrophysics Data System (ADS)

Miyazaki, Tadakuni; Tokumura, Kimiaki; Sugita, Mikio

1997-12-01

The casi has the spatial resolution of about 3 m X 3 m at the ground level and its spectral resolution is about 6 nm. The wavelength range for the measurement is from 430 to 870 nm and the number of the bands is 72 bands. An airplane carrying casi flew over Kuroshima Island, Okinawa and acquired image data of Kuroshima Island and the surrounding sea area. The flight courses were 6 courses at the altitude of 9,000 feet and 2 courses of 6,000 feet. At the same time, spectral measurements of the sea surface and several coral reefs underwater were carried out at an area of coral reefs off Kuroshima Island. The supervised and unsupervised classification were applied to the casi imageries to extract and classify the area of coral reefs off Kuroshima Island. The produced classification maps of the coral reefs were compared with the ground truth map of coral reefs made by the professional divers to evaluate the results. The results showed significant similarity of the distribution pattern of corral reefs.

The Stratospheric Observatory for Infrared Astronomy (sofia)

NASA Astrophysics Data System (ADS)

Gehrz, R. D.; Becklin, E. E.

2012-06-01

The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (SOFIA) is a 2.5- meter infrared airborne telescope in a Boeing 747-SP. SOFIA can conduct photometric, spectroscopic, and imaging observations at wavelengths from 0.3 microns to 1.6 millimeters. At SOFIA's maximum service ceiling of 45,000 feet, the average transmission at these wavelengths is greater than 80 percent. SOFIA flys out of the NASA Dryden Flight Research Center aircraft operations facility at Palmdale, CA and the SOFIA Science Mission Operations (SMO) Center is located at NASA Ames Research Center, Moffett Field, CA. SOFIA's first-generation instrument complement includes broadband imagers and spectrographs that can resolve spectral features due to dust and large molecules, and high resolution spectrometers facilitating kinematic studies of molecular and atomic gas lines at km/s resolution. More than 30 science flights of 10 hours length (take-off to landing) were conducted in the past year. About 100 eight to ten hour flights per year are planned by 2014, and the observatory will operate until the mid-2030's.

StarCAT: A Catalog of Space Telescope Imaging Spectrograph Ultraviolet Echelle Spectra of Stars

NASA Astrophysics Data System (ADS)

Ayres, Thomas R.

2010-03-01

StarCAT is a catalog of high resolution ultraviolet spectra of objects classified as "stars," recorded by Space Telescope Imaging Spectrograph (STIS) during its initial seven years of operations (1997-2004). StarCAT is based on 3184 echelle observations of 545 distinct targets, with a total exposure duration of 5.2 Ms. For many of the objects, broad ultraviolet coverage has been achieved by splicing echellegrams taken in two or more FUV (1150-1700 Å) and/or NUV (1600-3100 Å) settings. In cases of multiple pointings on conspicuously variable sources, spectra were separated into independent epochs. Otherwise, different epochs were combined to enhance the signal-to-noise ratio (S/N). A post-facto correction to the calstis pipeline data sets compensated for subtle wavelength distortions identified in a previous study of the STIS calibration lamps. An internal "fluxing" procedure yielded coherent spectral energy distributions (SEDs) for objects with broadly overlapping wavelength coverage. The best StarCAT material achieves 300 m s-1 internal velocity precision; absolute accuracy at the 1 km s-1 level; photometric accuracy of order 4%; and relative flux precision several times better (limited mainly by knowledge of SEDs of UV standard stars). While StarCAT represents a milestone in the large-scale post-processing of STIS echellegrams, a number of potential improvements in the underlying "final" pipeline are identified.

Space vehicle glow measurements on STS 41-D

NASA Technical Reports Server (NTRS)

Mende, S. B.; Swenson, G. R.; Clifton, K. S.; Gause, R.; Leger, L.; Garriott, O. K.

1985-01-01

A flight experiment using a hand-held, image-intensified spectrographic camera was performed on mission 41-D. The instrument enabled the photographic documentation of the position of the spectral slit on the image to be subjected to spectrographic analysis. Because of this instrument feature, the spectrum of the glow on the Shuttle tail pod could be clearly separated from spectrum of the scattered light from the Orbiter. From the measurements it is clear that the spectrum of the glow is a continuum in the passband of the instrument between 4200 A and 8000 A. The measured spectral resolution of the instrument was 35 A. The scattered light from the Orbiter surfaces distinctly show the components of the earth's airglow at 5577 A and 7620 A. On the same flight material samples were also carried by the Orbiter attached to the Remote Manipulating System arm. These samples were representative of the material overcoatings used on the space telescope. The altitude of the 41-D flight was 290 km, instead of the 220 km which was originally planned for this experiment. The signal to noise ratio in the material glow discrimination experiment was quite low. This made it difficult to draw strong conclusions regarding the glow propensity of the materials. Nevertheless it was clear that polyethylene produces a very weak glow, while most black overcoating materials produce significant glow. MgF2 was also found to produce a relatively intense glow.

Doppler Imaging of Exoplanets and Brown Dwarfs

NASA Astrophysics Data System (ADS)

Crossfield, I.; Biller, B.; Schlieder, J.; Deacon, N.; Bonnefoy, M.; Homeier, D.; Allard, F.; Buenzli, E.; Henning, T.; Brandner, W.; Goldman, Bertr; Kopytova, T.

2014-03-01

Doppler Imaging produces 2D global maps. When applied to cool planets or more massive brown dwarfs, it can map atmospheric features and track global weather patterns. The first substellar map, of the 2pc-distant brown dwarf Luhman 16B (Crossfeld et al. 2014), revealed patchy regions of thin & thick clouds. Here, I investigate the feasibility of future Doppler Imaging of additional objects. Searching the literature, I find that all 3 of P, v sin i, and variability are published for 22 brown dwarfs. At least one datum exists for 333 targets. The sample is very incomplete below ~L5; we need more surveys to find the best targets for Doppler Imaging! I estimate limiting magnitudes for Doppler Imaging with various hi-resolution near-infrared spectrographs. Only a handful of objects - at the M/L and L/T transitions - can be mapped with current tools. Large telescopes such as TMT and GMT will allow Doppler Imaging of many dozens of brown dwarfs and the brightest exoplanets. More targets beyond type L5 likely remain to be found. Future observations will let us probe the global atmospheric dynamics of many diverse objects.

Immersion echelle spectrograph

DOEpatents

Stevens, Charles G.; Thomas, Norman L.

2000-01-01

A small spectrograph containing no moving components and capable of providing high resolution spectra of the mid-infrared region from 2 microns to 4 microns in wavelength. The resolving power of the spectrograph exceeds 20,000 throughout this region and at an optical throughput of about 10.sup.-5 cm.sup.2 sr. The spectrograph incorporates a silicon immersion echelle grating operating in high spectral order combined with a first order transmission grating in a cross-dispersing configuration to provide a two-dimensional (2-D) spectral format that is focused onto a two-dimensional infrared detector array. The spectrometer incorporates a common collimating and condensing lens assembly in a near aberration-free axially symmetric design. The spectrometer has wide use potential in addition to general research, such as monitoring atmospheric constituents for air quality, climate change, global warming, as well as monitoring exhaust fumes for smog sources or exhaust plumes for evidence of illicit drug manufacture.

Far Ultraviolet Imaging from the Image Spacecraft

NASA Technical Reports Server (NTRS)

Mende, S. B.; Heetderks, H.; Frey, H. U.; Lampton, M.; Geller, S. P.; Stock, J. M.; Abiad, R.; Siegmund, O. H. W.; Tremsin, A. S.; Habraken, S.

2000-01-01

Direct imaging of the magnetosphere by the IMAGE spacecraft will be supplemented by observation of the global aurora. The IMAGE satellite instrument complement includes three Far Ultraviolet (FUV) instruments. The Wideband Imaging Camera (WIC) will provide broad band ultraviolet images of the aurora for maximum spatial and temporal resolution by imaging the LBH N2 bands of the aurora. The Spectrographic Imager (SI), a novel form of monochromatic imager, will image the aurora, filtered by wavelength. The proton-induced component of the aurora will be imaged separately by measuring the Doppler-shifted Lyman-a. Finally, the GEO instrument will observe the distribution of the geocoronal emission to obtain the neutral background density source for charge exchange in the magnetosphere. The FUV instrument complement looks radially outward from the rotating IMAGE satellite and, therefore, it spends only a short time observing the aurora and the Earth during each spin. To maximize photon collection efficiency and use efficiently the short time available for exposures the FUV auroral imagers WIC and SI both have wide fields of view and take data continuously as the auroral region proceeds through the field of view. To minimize data volume, the set of multiple images are electronically co-added by suitably shifting each image to compensate for the spacecraft rotation. In order to minimize resolution loss, the images have to be distort ion-corrected in real time. The distortion correction is accomplished using high speed look up tables that are pre-generated by least square fitting to polynomial functions by the on-orbit processor. The instruments were calibrated individually while on stationary platforms, mostly in vacuum chambers. Extensive ground-based testing was performed with visible and near UV simulators mounted on a rotating platform to emulate their performance on a rotating spacecraft.

Progress along the E-ELT instrumentation roadmap

NASA Astrophysics Data System (ADS)

Ramsay, Suzanne; Casali, Mark; Cirasuolo, Michele; Egner, Sebastian; Gray, Peter; Gonzáles Herrera, Juan Carlos; Hammersley, Peter; Haupt, Christoph; Ives, Derek; Jochum, Lieselotte; Kasper, Markus; Kerber, Florian; Lewis, Steffan; Mainieri, Vincenzo; Manescau, Antonio; Marchetti, Enrico; Oberti, Sylvain; Padovani, Paolo; Schmid, Christian; Schimpelsberger, Johannes; Siebenmorgen, Ralf; Szecsenyi, Orsolya; Tamai, Roberto; Vernet, Joël.

2016-08-01

A suite of seven instruments and associated AO systems have been planned as the "E-ELT Instrumentation Roadmap". Following the E-ELT project approval in December 2014, rapid progress has been made in organising and signing the agreements for construction with European universities and institutes. Three instruments (HARMONI, MICADO and METIS) and one MCAO module (MAORY) have now been approved for construction. In addition, Phase-A studies have begun for the next two instruments - a multi-object spectrograph and high-resolution spectrograph. Technology development is also ongoing in preparation for the final instrument in the roadmap, the planetary camera and spectrograph. We present a summary of the status and capabilities of this first set of instruments for the E-ELT.

Science highlights from MAVEN/IUVS after two years in Mars Orbit

NASA Astrophysics Data System (ADS)

Schneider, N. M.; Deighan, J.; Stiepen, A.; Jain, S.; Lefèvre, F.; Stevens, M. H.; Gröller, H.; Yelle, R. V.; Lo, D.; Evans, J. S.; Stewart, I. F.; Chaffin, M.; Crismani, M. M. J.; Mayyasi, M.; McClintock, W. E.; Holsclaw, G.; Clarke, J. T.; Montmessin, F.; Jakosky, B. M.

2016-12-01

The broad capabilities of the Imaging UltraViolet Spectrograph on the MAVEN mission are enabling new science ranging from Mars' lower atmosphere up though the escaping corona. After two years in Mars orbit, the instrument has yielded insights on present-day processes at Mars including dayglow, nightglow, aurora, meteor showers, clouds, and solar-planetary interactions. In this presentation we will highlight several new discoveries in the mesosphere and below. First, spatial mapping of nitric oxide nightglow reveals regions of atmospheric downwelling necessitating substantial changes to global atmospheric circulation models. Second, a new high-spatial-resolution UV imaging mode allows detection of clouds from nadir to limb and their local time evolution, as well as unprecedented determinations of Mars' low-altitude ozone. Finally, IUVS has obtained hundreds of stellar occultation profiles probing atmospheric structure, composition, waves and tides.

Visible camera cryostat design and performance for the SuMIRe Prime Focus Spectrograph (PFS)

NASA Astrophysics Data System (ADS)

Smee, Stephen A.; Gunn, James E.; Golebiowski, Mirek; Hope, Stephen C.; Madec, Fabrice; Gabriel, Jean-Francois; Loomis, Craig; Le fur, Arnaud; Dohlen, Kjetil; Le Mignant, David; Barkhouser, Robert; Carr, Michael; Hart, Murdock; Tamura, Naoyuki; Shimono, Atsushi; Takato, Naruhisa

2016-08-01

We describe the design and performance of the SuMIRe Prime Focus Spectrograph (PFS) visible camera cryostats. SuMIRe PFS is a massively multi-plexed ground-based spectrograph consisting of four identical spectrograph modules, each receiving roughly 600 fibers from a 2394 fiber robotic positioner at the prime focus. Each spectrograph module has three channels covering wavelength ranges 380 nm - 640 nm, 640 nm - 955 nm, and 955 nm - 1.26 um, with the dispersed light being imaged in each channel by a f/1.07 vacuum Schmidt camera. The cameras are very large, having a clear aperture of 300 mm at the entrance window, and a mass of 280 kg. In this paper we describe the design of the visible camera cryostats and discuss various aspects of cryostat performance.

VizieR Online Data Catalog: Spectroscopy of EG And over roughly 14 years (Kenyon+, 2016)

NASA Astrophysics Data System (ADS)

Kenyon, S. J.; Garcia, M. R.

2016-08-01

From 1994 September to 2016 January, P. Berlind, M. Calkins, and other observers acquired 480 low-resolution optical spectra of EG And with FAST, a high throughput, slit spectrograph mounted at the Fred L. Whipple Observatory 1.5m telescope on Mount Hopkins, Arizona They used a 300g/mm grating blazed at 4750Å, a 3'' slit, and a thinned 512*2688 CCD. These spectra cover 3800-7500Å at a resolution of 6Å. The full wavelength solution is derived from calibration lamps acquired immediately after each exposure. The wavelength solution for each frame has a probable error of <~+/-0.5Å. Most of the resulting spectra have moderate signal-to-noise ratio, S/N >~15-30 per pixel. Prior to the start of the FAST observations, we obtained occasional optical spectrophotometric observations of EG And throughout 1982-1989 with the cooled dual-beam intensified Reticon scanner (IRS) mounted on the white spectrograph at the KPNO No. 1 and No. 2 90cm telescopes. Various remote observers acquired high-resolution spectroscopic observations of EG And with the echelle spectrographs and Reticon detectors on the 1.5m telescopes of the Fred L. Whipple Observatory on Mount Hopkins, Arizona and the Oak Ridge Observatory in Harvard, Massachusetts. These spectra cover a 44Å bandpass centered near 5190Å or 5200Å and have a resolution of roughly 12km/s. (1 data file).

VizieR Online Data Catalog: Candidate eruptive young stars in Lynds 1340 (Kun+, 2014)

NASA Astrophysics Data System (ADS)

Kun, M.; Apai, D.; O'Linger-Luscusk, J.; Moor, A.; Stecklum, B.; Szegedi-Elek, E.; Wolf-Chase, G.

2016-07-01

Lynds 1340 was observed by the Spitzer Space Telescope using the Infrared Array Camera (IRAC) on 2009 March 16 and the Multiband Imaging Photometer (MIPS) for Spitzer on 2008 November 26 (Prog. ID: 50691, PI: G. Fazio). The observations covered ~1deg2 in each band. We obtained low-resolution optical spectra for the star coinciding with IRAS 02224+7227 on 2003 February 5 using CAFOS with the G-100 grism on the 2.2m Telescope of the Calar Alto Observatory, and on 2004 December 11 using FAST on the 1.5m FLWO Telescope. High angular resolution JHK images, centered on the same star, were obtained on 2002 October 24 using the near-infrared camera Omega-Cass, mounted on the 3.5m Telescope of the Calar Alto Observatory. We performed a new search for Hα emission stars in L1340 using the Wide Field Grism Spectrograph 2 installed on the University of Hawaii 2.2m Telescope. We observed 2MASS J02263797+7304575 on 2011 October 16 and detected a Hα emission with EW(Hα)=-80Å in its spectrum. The Ks magnitude of 2MASS J02325605+7246055 was measured on the images obtained on 2010 October 18, during the monitoring program of V1180 Cas (Kun et al. 2011, J/ApJ/733/L8), using the MAGIC camera on the 2.2m Telescope of the Calar Alto Observatory. Narrow-band images through [SII] and Hα filters, as well as broad R-band images containing the environment of 2MASSJ02325605+7246055, were obtained with the Schmidt Telescope of the Thuringer Landessternwarte (TLS), Tautenburg in 2011 May, June, and September. Spectra of the nebula and the two brightest HH knots were obtained using the TLS medium-resolution Nasmyth spectrograph (R~700) in 2011 November. BVRCIC photometric observations of IRAS 02224+7227 were performed with the 1m Ritchey-Chretien-Coude (RCC) Telescope of the Konkoly Observatory at three epochs between 2001 and 2011. We measured the RC and IC magnitudes of IRAS 02224+7227 and 2MASSJ02263797+7304575 at several epochs between 2011 January and 2014 June on the images collected with the wide-field camera on the Schmidt Telescope of the Konkoly Observatory to monitor the light variations of V1180 Cas (Kun et al. 2011, J/ApJ/733/L8). L1340 is situated within Stripe 1260 of the SEGUE survey (Yanny et al. 2009, J/AJ/137/4377), thus its entire area was observed in the ugriz bands in 2005 November-December. Each target star has high-quality 3.4, 4.6, 12, and 22um fluxes in the AllWISE data base. (1 data file).

VizieR Online Data Catalog: Black hole masses in megamaser disk galaxies (Greene+, 2016)

NASA Astrophysics Data System (ADS)

Greene, J. E.; Seth, A.; Kim, M.; Lasker, R.; Goulding, A.; Gao, F.; Braatz, J. A.; Henkel, C.; Condon, J.; Lo, K. Y.; Zhao, W.

2016-11-01

The velocity dispersion (σ*) presented here for megamaser disk galaxies are measured from three data sets. Two galaxies (NGC1320, NGC5495) were observed with the B&C spectrograph on the Dupont telescope at the Las Campanas Observatory. These spectra have an instrumental resolution of σr~120km/s and a wavelength range of 3400-6000Å. Two galaxies (Mrk1029, ESO558-G009) have σ* measurements from the cross-dispersed near-infrared spectrograph Triplespec on the 3.5m telescope at Apache Point. Triplespec has a wavelength range of 0.9-2.4um with a spectral resolution of σr~37km/s. Finally, three galaxies (J0437+2456, NGC5765b, UGC6093) have spectra from the SDSS. They have a spectral resolution of σr~65km/s and cover a range of 3800-9200Å. (1 data file).

PISCES High Contrast Integral Field Spectrograph Simulations and Data Reduction Pipeline

NASA Technical Reports Server (NTRS)

Llop Sayson, Jorge Domingo; Memarsadeghi, Nargess; McElwain, Michael W.; Gong, Qian; Perrin, Marshall; Brandt, Timothy; Grammer, Bryan; Greeley, Bradford; Hilton, George; Marx, Catherine

2015-01-01

The PISCES (Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies) is a lenslet array based integral field spectrograph (IFS) designed to advance the technology readiness of the WFIRST (Wide Field Infrared Survey Telescope)-AFTA (Astrophysics Focused Telescope Assets) high contrast Coronagraph Instrument. We present the end to end optical simulator and plans for the data reduction pipeline (DRP). The optical simulator was created with a combination of the IDL (Interactive Data Language)-based PROPER (optical propagation) library and Zemax (a MatLab script), while the data reduction pipeline is a modified version of the Gemini Planet Imager's (GPI) IDL pipeline. The simulations of the propagation of light through the instrument are based on Fourier transform algorithms. The DRP enables transformation of the PISCES IFS data to calibrated spectral data cubes.

Beyond MOS and Fibers: Wide-FoV Imaging Fourier Transform Spectroscopy - an Instrumentation Proposal for the Present and Future Mexican Telescopes

NASA Astrophysics Data System (ADS)

Rosales-Ortega, F. F.; Castillo, E.; Sánchez, S. F.; Iglesias-Páramo, J.; Mollá, J. I. M.; Chávez, M.

2016-10-01

In order to extend the current suite of instruments offered in the Observatorio Astrofísico Guillermo Haro (OAGH) in Cananea, Mexico (INAOE), and to explore a second-generation instrument for the future 6.5 m Telescopio San Pedro Martir (TSPM), we propose a prototype instrument that will provide un-biased wide-field (few arcmin) spectroscopic information, with the flexibility of operating at different spectral resolutions (R˜1-104), with a spatial resolution limited by seeing, and therefore to be used in a wide range of astronomical problems. This instrument will make use of the Fourier Transform Spectroscopy technique, which has been proved to be feasible in the optical wavelength range. Here we give the basic technical description of a Fourier transform spectrograph, as well as the technical advantages and weaknesses, and the science cases in which this instrument can be implemented.

Report of the facility definition team spacelab UV-Optical Telescope Facility

NASA Technical Reports Server (NTRS)

1975-01-01

Scientific requirements for the Spacelab Ultraviolet-Optical Telescope (SUOT) facility are presented. Specific programs involving high angular resolution imagery over wide fields, far ultraviolet spectroscopy, precisely calibrated spectrophotometry and spectropolarimetry over a wide wavelength range, and planetary studies, including high resolution synoptic imagery, are recommended. Specifications for the mounting configuration, instruments for the mounting configuration, instrument mounting system, optical parameters, and the pointing and stabilization system are presented. Concepts for the focal plane instruments are defined. The functional requirements of the direct imaging camera, far ultraviolet spectrograph, and the precisely calibrated spectrophotometer are detailed, and the planetary camera concept is outlined. Operational concepts described in detail are: the makeup and functions of shuttle payload crew, extravehicular activity requirements, telescope control and data management, payload operations control room, orbital constraints, and orbital interfaces (stabilization, maneuvering requirements and attitude control, contamination, utilities, and payload weight considerations).

CARMENES. Mining public archives for stellar parameters and spectra of M dwarfs with master thesis students

NASA Astrophysics Data System (ADS)

Caballero, J. A.; Montes, D.; Alonso-Floriano, F. J.; Cortés-Contreras, M.; González-Álvarez, E.; Hidalgo, D.; Holgado, G.; Martínez-Rodríguez, H.; Sanz-Forcada, J.; López-Santiago, J.

2015-05-01

We are compiling the most comprehensive database of M dwarfs ever built, CARMENCITA, the CARMENES Cool dwarf Information and daTa Archive, which will be the CARMENES 'input catalogue'. In addition to the science preparation with low- and high-resolution spectrographs and lucky imagers, we compile a huge pile of public data on over 2200 M dwarfs, and analyse them, mostly using virtual-observatory tools. Here we describe four specific actions carried out by master students. They mine public archives for additional high-resolution spectroscopy (UVES, FEROS and HARPS), multi-band photometry (FUV-NUV-u-B-g-V-r-R-i-J-H-Ks-W1-W2-W3-W4), X-ray data (ROSAT, XMM-Newton and Chandra), and periods, rotational velocities and Hα pseudo-equivalent widths. As described, there are many interdependences between all these data.

SOFIA, an airborne observatory for infrared astronomy

NASA Astrophysics Data System (ADS)

Krabbe, Alfred; Mehlert, Dörte; Röser, Hans-Peter; Scorza, Cecilia

2013-11-01

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a joint US/German project operating a 2.7 m infrared airborne telescope onboard a modified Boeing 747-SP in the stratosphere at altitudes up to 13.7 km. SOFIA covers a spectral range from 0.3 µm to 1.6 mm, with an average atmospheric transmission greater than 80%. After successfully completing its commissioning, SOFIA commenced regular astronomical observation in spring 2013, and will ramp up to more than one hundred 8 to 10 h flights per year by 2015. The observatory is expected to operate until the mid 2030s. SOFIA's initial complement of seven focal plane instruments includes broadband imagers, moderate-resolution spectrographs and high-resolution spectrometers. SOFIA also includes an elaborate program for Education and Public Outreach. We describe the SOFIA facility together with its first light instrumentation and include some of its first scientific results. In addition, the education and public outreach program is presented.

Variability in the vacuum-ultraviolet transmittance of magnesium fluoride windows. [for Space Telescope Imaging Spectrograph

NASA Technical Reports Server (NTRS)

Herzig, Howard; Fleetwood, Charles M., Jr.; Toft, Albert R.

1992-01-01

Sample window materials tested during the development of a domed magnesium fluoride detector window for the Hubble Space Telescope's Imaging Spectrograph are noted to exhibit wide variability in VUV transmittance; a test program was accordingly instituted to maximize a prototype domed window's transmittance. It is found that VUV transmittance can be maximized if the boule from which the window is fashioned is sufficiently large to allow such a component to be cut from the purest available portion of the boule.

The re-flight of the Colorado high-resolution Echelle stellar spectrograph (CHESS): improvements, calibrations, and post-flight results

NASA Astrophysics Data System (ADS)

Hoadley, Keri; France, Kevin; Kruczek, Nicholas; Fleming, Brian; Nell, Nicholas; Kane, Robert; Swanson, Jack; Green, James; Erickson, Nicholas; Wilson, Jacob

2016-07-01

In this proceeding, we describe the scientific motivation and technical development of the Colorado High- resolution Echelle Stellar Spectrograph (CHESS), focusing on the hardware advancements and testing supporting the second flight of the payload (CHESS-2). CHESS is a far ultraviolet (FUV) rocket-borne instrument designed to study the atomic-to-molecular transitions within translucent cloud regions in the interstellar medium (ISM). CHESS is an objective f/12.4 echelle spectrograph with resolving power > 100,000 over the band pass 1000 - 1600 Å. The spectrograph was designed to employ an R2 echelle grating with "low" line density. We compare the FUV performance of experimental echelle etching processes (lithographically by LightSmyth, Inc. and etching via electron-beam technology by JPL Microdevices Laboratory) with traditional, mechanically-ruled gratings (Bach Research, Inc. and Richardson Gratings). The cross-dispersing grating, developed and ruled by Horiba Jobin-Yvon, is a holographically-ruled, "low" line density, powered optic with a toroidal surface curvature. Both gratings were coated with aluminum and lithium fluoride (Al+LiF) at Goddard Space Flight Center (GSFC). Results from final efficiency and reflectivity measurements for the optical components of CHESS-2 are presented. CHESS-2 utilizes a 40mm-diameter cross-strip anode readout microchannel plate (MCP) detector fabricated by Sensor Sciences, Inc., to achieve high spatial resolution with high count rate capabilities (global rates 1 MHz). We present pre-flight laboratory spectra and calibration results. CHESS-2 launched on 21 February 2016 aboard NASA/CU sounding rocket mission 36.297 UG. We observed the intervening ISM material along the sightline to epsilon Per and present initial characterization of the column densities, temperature, and kinematics of atomic and molecular species in the observation.

The Mars Microbeam Raman Spectrometer: An Improved Advanced Brassboard

NASA Technical Reports Server (NTRS)

Haskin, L. A.; Wang, Alian

2003-01-01

An advanced brassboard (ADBB) of the Mars Miscrobeam Raman Spectrometer is being developed. The probe and spectrograph have been redesigned with improved optics and the electronics have been miniaturized. The modified optical design in the probe and spectrograph provides better spectral resolution than the previous model and enables the probe design to be more compatible with robotic arm deployment. The CCD detector is now cooled thermoelectrically in anticipation of eventual terrestrial field testing of the instrument.

Magnetic field geometry and chemical abundance distribution of the He-strong star CPD -57°3509

NASA Astrophysics Data System (ADS)

Hubrig, S.; Przybilla, N.; Korhonen, H.; Ilyin, I.; Schöller, M.; Järvinen, S. P.; Nieva, M.-F.; Scholz, R.-D.; Kimeswenger, S.; Ramolla, M.; Kholtygin, A. F.; Briquet, M.

2017-10-01

The magnetic field of CPD -57°3509 was recently detected in the framework of the BOB (B fields in OB stars) collaboration. We acquired low-resolution spectropolarimetric observations of CPD -57°3509 with the FOcal Reducer low-dispersion Spectrograph 2 and high-resolution UV-Visual Echelle Spectrograph observations randomly distributed over a few months to search for periodicity, to study the magnetic field geometry and to determine the surface distribution of silicon and helium. We also obtained supplementary photometric observations at a timeline similar to the spectroscopic and spectropolarimetric observations. A period of 6.36 d was detected in the measurements of the mean longitudinal magnetic field. A sinusoidal fit to our measurements allowed us to constrain the magnetic field geometry and estimate the dipole strength in the range of 3.9-4.5 kG. Our application of the Doppler imaging technique revealed the presence of He I spots located around the magnetic poles, with a strong concentration at the positive pole and a weaker one around the negative pole. In contrast, high-concentration Si III spots are located close to the magnetic equator. Furthermore, our analysis of the spectral variability of CPD -57°3509 on short time-scales indicates distinct changes in shape and position of line profiles possibly caused by the presence of β Cep like pulsations. A small periodic variability in line with the changes of the magnetic field strength is clearly seen in the photometric data.

Precision stellar radial velocity measurements with FIDEOS at the ESO 1-m telescope of La Silla

NASA Astrophysics Data System (ADS)

Vanzi, L.; Zapata, A.; Flores, M.; Brahm, R.; Tala Pinto, M.; Rukdee, S.; Jones, M.; Ropert, S.; Shen, T.; Ramirez, S.; Suc, V.; Jordán, A.; Espinoza, N.

2018-07-01

We present results from the commissioning and early science programs of FIbre Dual Echelle Optical Spectrograph (FIDEOS), the new high-resolution echelle spectrograph developed at the Centre of Astro Engineering of Pontificia Universidad Catolica de Chile, and recently installed at the ESO 1-m telescope of La Silla. The instrument provides spectral resolution R ˜ 43 000 in the visible spectral range 420-800 nm, reaching a limiting magnitude of 11 in V band. Precision in the measurement of radial velocity is guaranteed by light feeding with an octagonal optical fibre, suitable mechanical isolation, thermal stabilization, and simultaneous wavelength calibration. Currently the instrument reaches radial velocity stability of ˜8 m s-1 over several consecutive nights of observation.

The star identification, pointing and tracking system of UVSTAR, an attached payload instrument system for the Shuttle Hitchhiker-M platform

NASA Technical Reports Server (NTRS)

Decarlo, Francesco; Stalio, Roberto; Trampus, Paolo; Broadfoot, A. Lyle; Sandel, Bill R.; Sicuranza, Giovanni

1993-01-01

We describe an algorithm for star identification and pointing/tracking of a spaceborne electro-optical system and simulation analyses to test the algorithm. The algorithm will be implemented in the guiding system of UVSTAR, a spectrographic telescope for observations of astronomical and planetary sources operating in the 500-1250 A waveband at approximately 1 A resolution. The experiment is an attached payload and will fly as a Hitchhiker-M payload on the Shuttle. UVSTAR includes capabilities for independent target acquisition and tracking. The spectrograph package has internal gimbals that allow angular movement of plus or minus 3 deg from the central position. Rotation about the azimuth axis (parallel to the Shuttle z axis) and elevation axis (parallel to the Shuttle x axis) will actively position the field of view to center the target of interest in the fields of the spectrographs. The algorithm is based on an on-board catalog of stars. To identify star fields, the algorithm compares the positions of stars recorded by the guiding imager to positions computed from the on-board catalog. When the field has been identified, its position within the guiding imager field of view can be used to compute the pointing corrections necessary to point to a target of interest. In tracking mode, the software uses the past history to predict the quasi-periodic attitude control motions of the shuttle and sends pointing commands to cancel the motion and stabilize UVSTAR on the target. The guiding imager (guider) will have an 80-mm focal length and f/1.4 optics giving a field of view of 6 deg x 4.5 deg using a 385 x 288 pixel intensified CCD. It will be capable of providing high accuracy (better than 2 arc-sec) attitude determination from coarse (6 deg x 4.5 deg) initial knowledge of the pointing direction; and of pointing toward the target. It will also be capable of tracking at the same high accuracy with a processing time of less than a few hundredths of a second.

ERIS: preliminary design phase overview

NASA Astrophysics Data System (ADS)

Kuntschner, Harald; Jochum, Lieselotte; Amico, Paola; Dekker, Johannes K.; Kerber, Florian; Marchetti, Enrico; Accardo, Matteo; Brast, Roland; Brinkmann, Martin; Conzelmann, Ralf D.; Delabre, Bernard A.; Duchateau, Michel; Fedrigo, Enrico; Finger, Gert; Frank, Christoph; Rodriguez, Fernando G.; Klein, Barbara; Knudstrup, Jens; Le Louarn, Miska; Lundin, Lars; Modigliani, Andrea; Müller, Michael; Neeser, Mark; Tordo, Sebastien; Valenti, Elena; Eisenhauer, Frank; Sturm, Eckhard; Feuchtgruber, Helmut; George, Elisabeth M.; Hartl, Michael; Hofmann, Reiner; Huber, Heinrich; Plattner, Markus P.; Schubert, Josef; Tarantik, Karl; Wiezorrek, Erich; Meyer, Michael R.; Quanz, Sascha P.; Glauser, Adrian M.; Weisz, Harald; Esposito, Simone; Xompero, Marco; Agapito, Guido; Antichi, Jacopo; Biliotti, Valdemaro; Bonaglia, Marco; Briguglio, Runa; Carbonaro, Luca; Cresci, Giovanni; Fini, Luca; Pinna, Enrico; Puglisi, Alfio T.; Quirós-Pacheco, Fernando; Riccardi, Armando; Di Rico, Gianluca; Arcidiacono, Carmelo; Dolci, Mauro

2014-07-01

The Enhanced Resolution Imager and Spectrograph (ERIS) is the next-generation adaptive optics near-IR imager and spectrograph for the Cassegrain focus of the Very Large Telescope (VLT) Unit Telescope 4, which will soon make full use of the Adaptive Optics Facility (AOF). It is a high-Strehl AO-assisted instrument that will use the Deformable Secondary Mirror (DSM) and the new Laser Guide Star Facility (4LGSF). The project has been approved for construction and has entered its preliminary design phase. ERIS will be constructed in a collaboration including the Max- Planck Institut für Extraterrestrische Physik, the Eidgenössische Technische Hochschule Zürich and the Osservatorio Astrofisico di Arcetri and will offer 1 - 5 μm imaging and 1 - 2.5 μm integral field spectroscopic capabilities with a high Strehl performance. Wavefront sensing can be carried out with an optical high-order NGS Pyramid wavefront sensor, or with a single laser in either an optical low-order NGS mode, or with a near-IR low-order mode sensor. Due to its highly sensitive visible wavefront sensor, and separate near-IR low-order mode, ERIS provides a large sky coverage with its 1' patrol field radius that can even include AO stars embedded in dust-enshrouded environments. As such it will replace, with a much improved single conjugated AO correction, the most scientifically important imaging modes offered by NACO (diffraction limited imaging in the J to M bands, Sparse Aperture Masking and Apodizing Phase Plate (APP) coronagraphy) and the integral field spectroscopy modes of SINFONI, whose instrumental module, SPIFFI, will be upgraded and re-used in ERIS. As part of the SPIFFI upgrade a new higher resolution grating and a science detector replacement are envisaged, as well as PLC driven motors. To accommodate ERIS at the Cassegrain focus, an extension of the telescope back focal length is required, with modifications of the guider arm assembly. In this paper we report on the status of the baseline design. We will also report on the main science goals of the instrument, ranging from exoplanet detection and characterization to high redshift galaxy observations. We will also briefly describe the SINFONI-SPIFFI upgrade strategy, which is part of the ERIS development plan and the overall project timeline.

DMDs for multi-object near-infrared spectrographs in astronomy

NASA Astrophysics Data System (ADS)

Smee, Stephen A.; Barkhouser, Robert; Hope, Stephen; Conley, Devin; Gray, Aidan; Hope, Gavin; Robberto, Massimo

2018-02-01

The Digital Micromirror Device (DMD), typically used in projection screen technology, has utility in instrumentation for astronomy as a digitally programmable slit in a spectrograph. When placed at an imaging focal plane the device can be used to selectively direct light from astronomical targets into the optical path of a spectrograph, while at the same time directing the remaining light into an imaging camera, which can be used for slit alignment, science imaging, or both. To date the use of DMDs in astronomy has been limited, especially for instruments that operate in the near infrared (1 - 2.5 μm). This limitation is due in part to a host of technical challenges with respect to DMDs that, to date, have not been thoroughly explored. Those challenges include operation at cryogenic temperature, control electronics that facilitate DMD use at these temperatures, window coatings properly coated for the near infrared bandpass, and scattered light. This paper discusses these technical challenges and presents progress towards understanding and mitigating them.

Deuterium Abundance Toward G191-B2B: Results from the Far Ultraviolet Spectroscopic Explorer (FUSE) Mission

NASA Technical Reports Server (NTRS)

Lemoine, M.; Vidal-Madjar, A.; Hebrard, G.; Desert, J.-M.; Ferlet, R.; LecavelierdesEtangs, A.; Howk, J. C.; Andre, M.; Blair, W. P.; Friedman, S. D.;

PRAXIS: a low background NIR spectrograph for fibre Bragg grating OH suppression

NASA Astrophysics Data System (ADS)

Horton, Anthony; Ellis, Simon; Lawrence, Jon; Bland-Hawthorn, Joss

2012-09-01

Fibre Bragg grating (FBG) OH suppression is capable of greatly reducing the bright sky background seen by near infrared spectrographs. By filtering out the airglow emission lines at high resolution before the light enters the spectrograph this technique prevents scattering from the emission lines into interline regions, thereby reducing the background at all wavelengths. In order to take full advantage of this sky background reduction the spectrograph must have very low instrumental backgrounds so that it remains sky noise limited. Both simulations and real world experience with the prototype GNOSIS system show that existing spectrographs, designed for higher sky background levels, will be unable to fully exploit the sky background reduction. We therefore propose PRAXIS, a spectrograph optimised specifically for this purpose. The PRAXIS concept is a fibre fed, fully cryogenic, fixed format spectrograph for the J and H-bands. Dark current will be minimised by using the best of the latest generation of NIR detectors while thermal backgrounds will be reduced by the use of a cryogenic fibre slit. Optimised spectral formats and the use of high throughput volume phase holographic gratings will further enhance sensitivity. Our proposal is for a modular system, incorporating exchangeable fore-optics units, integral field units and OH suppression units, to allow PRAXIS to operate as a visitor instrument on any large telescope and enable new developments in FBG OH suppression to be incorporated as they become available. As a high performance fibre fed spectrograph PRAXIS could also serve as a testbed for other astrophotonic technologies.

Simulating the WFIRST coronagraph integral field spectrograph

NASA Astrophysics Data System (ADS)

Rizzo, Maxime J.; Groff, Tyler D.; Zimmermann, Neil T.; Gong, Qian; Mandell, Avi M.; Saxena, Prabal; McElwain, Michael W.; Roberge, Aki; Krist, John; Riggs, A. J. Eldorado; Cady, Eric J.; Mejia Prada, Camilo; Brandt, Timothy; Douglas, Ewan; Cahoy, Kerri

2017-09-01

A primary goal of direct imaging techniques is to spectrally characterize the atmospheres of planets around other stars at extremely high contrast levels. To achieve this goal, coronagraphic instruments have favored integral field spectrographs (IFS) as the science cameras to disperse the entire search area at once and obtain spectra at each location, since the planet position is not known a priori. These spectrographs are useful against confusion from speckles and background objects, and can also help in the speckle subtraction and wavefront control stages of the coronagraphic observation. We present a software package, the Coronagraph and Rapid Imaging Spectrograph in Python (crispy) to simulate the IFS of the WFIRST Coronagraph Instrument (CGI). The software propagates input science cubes using spatially and spectrally resolved coronagraphic focal plane cubes, transforms them into IFS detector maps and ultimately reconstructs the spatio-spectral input scene as a 3D datacube. Simulated IFS cubes can be used to test data extraction techniques, refine sensitivity analyses and carry out design trade studies of the flight CGI-IFS instrument. crispy is a publicly available Python package and can be adapted to other IFS designs.

An Integral-Field Spectrograph for a Terrestrial Planet Finding Mission

NASA Technical Reports Server (NTRS)

Heap, Sara R.

2011-01-01

We describe a conceptual design for an integral field spectrograph for characterizing exoplanets that we developed for NASA's Terrestrial Planet Finder Coronagraph (TPF-C), although it is equally applicable to an external-occulter mission. The spectrograph fulfills all four scientific objectives of a terrestrial planet finding mission by: (1) Spectrally characterizing the atmospheres of detected planets in search of signatures of habitability or even biological activity; (2) Directly detecting terrestrial planets in the habitable zone around nearby stars; (3) Studying all constituents of a planetary system including terrestrial and giant planets, gas and dust around sun-like stars of different ages and metallicities; (4) Enabling simultaneous, high-spatial-resolution, spectroscopy of all astrophysical sources regardless of central source luminosity, such as AGN's, proplyds, etc.

The infrared spectrograph during the SIRTF pre-definition phase

NASA Technical Reports Server (NTRS)

Houck, James R.

1988-01-01

A test facility was set up to evaluate back-illuminated impurity band detectors constructed for an infrared spectrograph to be used on the Space Infrared Telescope Facility (SIRTF). Equipment built to perform the tests on these arrays is described. Initial tests have been geared toward determining dark current and read noise for the array. Four prior progress reports are incorporated into this report. They describe the first efforts in the detector development and testing effort; testing details and a new spectrograph concept; a discussion of resolution issues raised by the new design; management activities; a review of computer software and testing facility hardware; and a review of the preamplifier constructed as well as a revised schematic of the detector evaluation facility.

Distribución Espacial de Ancho Equivalente del Triplete del CaII a partir de Imágenes GMOS

NASA Astrophysics Data System (ADS)

Díaz, R. J.; Mast, D.

Using Gemini+GMOS imagery obtained through the filters i, z and CaT, we developed a technique for estimating the value of the Ca II triplet (CaT) equivalent width (EW). The map generated through arithmetic operations with the near infrared images was calibrated with long slit spectra obtained with REOSC spectrograph at CASLEO. We apply this technique to the study of M 83 central region and present the preliminary results on the spatial distribution of the EW(CaT) within an area of 40 per 40 square arcsec around the double nucleus of M 83, with a spatial resolution of 0.8 arcsec. FULL TEXT IN SPANISH.

Hi-C OBSERVATIONS OF SUNSPOT PENUMBRAL BRIGHT DOTS

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

Alpert, Shane E.; Tiwari, Sanjiv K.; Moore, Ronald L.

We report observations of bright dots (BDs) in a sunspot penumbra using High Resolution Coronal Imager (Hi-C) data in 193 Å and examine their sizes, lifetimes, speeds, and intensities. The sizes of the BDs are on the order of 1″ and are therefore hard to identify in the Atmospheric Imaging Assembly (AIA) 193 Å images, which have a 1.″2 spatial resolution, but become readily apparent with Hi-C's spatial resolution, which is five times better. We supplement Hi-C data with data from AIA's 193 Å passband to see the complete lifetime of the BDs that appeared before and/or lasted longer thanmore » Hi-C's three-minute observation period. Most Hi-C BDs show clear lateral movement along penumbral striations, either toward or away from the sunspot umbra. Single BDs often interact with other BDs, combining to fade away or brighten. The BDs that do not interact with other BDs tend to have smaller displacements. These BDs are about as numerous but move slower on average than Interface Region Imaging Spectrograph (IRIS) BDs, which was recently reported by Tian et al., and the sizes and lifetimes are on the higher end of the distribution of IRIS BDs. Using additional AIA passbands, we compare the light curves of the BDs to test whether the Hi-C BDs have transition region (TR) temperatures like those of the IRIS BDs. The light curves of most Hi-C BDs peak together in different AIA channels, indicating that their temperatures are likely in the range of the cooler TR (1−4 × 10{sup 5} K).« less

Normal-incidence EXtreme-Ultraviolet imaging Spectrometer - NEXUS

NASA Astrophysics Data System (ADS)

Dere, K. P.

2003-05-01

NEXUS is the result of a breakthrough optical design that incorporates new technologies to achieve high optical throughput at high spatial (1 arcsec) and spectral (1-2 km s-1) resolution over a wide field of view in an optimal extreme-ultraviolet spectral band. This achievement was made possible primarily by two technical developments. First, a coating of boron-carbide deposited onto a layer of iridium provided a greatly enhanced reflectivity at EUV wavelengths that would enable NEXUS to observe the Sun over a wide temperature range at high cadence. The reflectivity of these coatings have been measured and demonstrated in the laboratory. The second key development was the use of a variable-line-spaced toroidal grating spectrometer. The spectrometer design allowed the Sun to be imaged at high spatial and spectral resolution along a 1 solar radius-long slit and over a wavelength range from 450 to 800 Å, nearly an entire spectral order. Because the spectrograph provided a magnification of about a factor of 6, only 2 optical elements are required to achieved the desired imaging performance. Throughput was enhanced by the use of only 2 reflections. The could all be accomodated within a total instrument length of 1.5m. We would like to acknowledge support from ONR

First light of the Gemini Planet Imager

DOE PAGES

Macintosh, Bruce; Graham, James R.; Ingraham, Patrick; ...

2014-05-12

The Gemini Planet Imager is a dedicated facility for directly imaging and spectroscopically characterizing extrasolar planets. It combines a very high-order adaptive optics system, a diffraction-suppressing coronagraph, and an integral field spectrograph with low spectral resolution but high spatial resolution. Every aspect of the Gemini Planet Imager has been tuned for maximum sensitivity to faint planets near bright stars. During first-light observations, we achieved an estimated H band Strehl ratio of 0.89 and a 5-σ contrast of 10 6 at 0.75 arcseconds and 10 5 at 0.35 arcseconds. Observations of Beta Pictoris clearly detect the planet, Beta Pictoris b, inmore » a single 60-s exposure with minimal postprocessing. Beta Pictoris b is observed at a separation of 434 ± 6 milliarcseconds (mas) and position angle 211.8 ± 0.5°. Fitting the Keplerian orbit of Beta Pic b using the new position together with previous astrometry gives a factor of 3 improvement in most parameters over previous solutions. The planet orbits at a semimajor axis of 9.0 +0.8 –0.4 AU near the 3:2 resonance with the previously known 6-AU asteroidal belt and is aligned with the inner warped disk. In conclusion, the observations give a 4% probability of a transit of the planet in late 2017.« less

Robotic Spectroscopy at the Dark Sky Observatory

NASA Astrophysics Data System (ADS)

Rosenberg, Daniel E.; Gray, Richard O.; Mashburn, Jonathan; Swenson, Aaron W.; McGahee, Courtney E.; Briley, Michael M.

2018-06-01

Spectroscopic observations using the classification-resolution Gray-Miller spectrograph attached to the Dark Sky Observatory 32 inch telescope (Appalachian State University, North Carolina) have been automated with a robotic script called the “Robotic Spectroscopist” (RS). RS runs autonomously during the night and controls all operations related to spectroscopic observing. At the heart of RS are a number of algorithms that first select and center the target star in the field of an imaging camera and then on the spectrograph slit. RS monitors the observatory weather station, and suspends operations and closes the dome when weather conditions warrant, and can reopen and resume observations when the weather improves. RS selects targets from a list using a queue-observing protocol based on observer-assigned priorities, but also uses target-selection criteria based on weather conditions, especially seeing. At the end of the night RS transfers the data files to the main campus, where they are reduced with an automatic pipeline. Our experience has shown that RS is more efficient and consistent than a human observer, and produces data sets that are ideal for automatic reduction. RS should be adaptable for use at other similar observatories, and so we are making the code freely available to the astronomical community.

A Rare Encounter with Very Massive Stars in NGC~3125-A1

NASA Astrophysics Data System (ADS)

Wofford, A.; Leitherer, C.; Chandar, R.; Bouret, J. C.

2014-09-01

Super star cluster A1 in the nearby starburst galaxy NGC~3125 shows broad He II λ1640 emission (FWHM ~ 1200 km/s) of unprecedented strength (equivalent width, EW = 7.1+/-0.4 angstroms). Previous attempts to characterize A1's massive star content were hampered by the low resolution of the UV spectrum and the lack of co-spatial panchromatic data. We obtained far-UV to near-IR spectroscopy of the two principal emitting regions in the galaxy with the Space Telescope Imaging Spectrograph and the Cosmic Origins Spectrograph on board the Hubble Space Telescope. We use these data to derive the ages, reddenings, masses, and Wolf-Rayet (WR) to O star ratios of three compact clusters in the galaxy. We rule out that the extraordinary HeII lambda 1640 emission and OV lambda 1371 absorption in A1 are due to an extremely flat upper Initial Mass Function (IMF), and suggest that they originate in the winds of Very Massive Stars ( > 120 Msun, VMS). In order to reproduce the properties of peculiar clusters such as A1, the stellar evolution tracks implemented in Starburst99 need to be extended to masses >120 Msun.

VizieR Online Data Catalog: Keck+Magellan survey for LLSs. III. (Prochaska+, 2015)

NASA Astrophysics Data System (ADS)

Prochaska, J. X.; O'Meara, J. M.; Fumagalli, M.; Bernstein, R. A.; Burles, S. M.

2016-01-01

The sample presented in this manuscript is intended to be a nearly all-inclusive set of Lyman Limit Systems (LLSs) discovered in the high-dispersion (echelle or echellette; R>5000) spectra that we have gathered at the Keck and Magellan telescopes. Regarding Keck, we have examined all of the data obtained by Principal Investigators (PIs) A. M. Wolfe and J. X. Prochaska at the W. M. Keck Observatory through 2012 April, and from PIs Burles, O'Meara, Bernstein, and Fumagalli at Magellan through 2012 July. We also include the Keck spectra analyzed by Penprase et al. (2010, J/ApJ/721/1). We present data obtained at the W. M. Keck and Las Campanas Observatories using the twin 10m Keck I and Keck II telescopes and the twin 6.5m Baade and Clay telescopes. Altogether, we used four spectrometers: (1) the High Resolution Echelle Spectrometer (HIRES); (2) the Echellette Spectrograph and Imager (ESI); (3) the Magellan Inamori Kyocera Echelle (MIKE); and (4) the Magellan Echellette Spectrograph (MagE). Observing logs for the HIRES and MIKE spectra are provided in Tables 1 and 2. (5 data files).

Branching Ratios for The Radiometric Calibration of EUNIS-2012

NASA Technical Reports Server (NTRS)

Daw, Adrian N.; Bhatia, A. K.; Rabin, Douglas M.

2012-01-01

The Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS) sounding rocket instrument is a two-channel imaging spectrograph that observes the solar corona and transition region with high spectral resolution and a rapid cadence made possible by unprecedented sensitivity. The upcoming flight will incorporate a new wavelength channel covering the range 524-630 Angstroms, the previously-flown 300-370 Angstroms channel, and the first flight demonstration of cooled active pixel sensor (APS) arrays. The new 524-630 Angstrom channel incorporates a Toroidal Varied Line Space (TVLS) grating coated with B4C/Ir, providing broad spectral coverage and a wide temperature range of 0.025 to 10 MK. Absolute radiometric calibration of the two channels is being performed using a hollow cathode discharge lamp and NIST-calibrated AXUV-100G photodiode. Laboratory observations of He I 584 Angstroms and He II 304 Angstroms provide absolute radiometric calibrations of the two channels at those two respective wavelengths by using the AXUV photodiode as a transfer standard. The spectral responsivity is being determined by observing line pairs with a common upper state in the spectra of Ne I-III and Ar II-III. Calculations of A-values for the observed branching ratios are in progress.

MUSE: the Multi-Slit Solar Explorer

NASA Astrophysics Data System (ADS)

Tarbell, Theodore D.; De Pontieu, Bart

2017-08-01

The Multi-Slit Solar Explorer is a proposed Small Explorer mission for studying the dynamics of the corona and transition region using both conventional and novel spectral imaging techniques. The physical processes that heat the multi-million degree solar corona, accelerate the solar wind and drive solar activity (CMEs and flares) remain poorly known. A breakthrough in these areas can only come from radically innovative instrumentation and state-of-the-art numerical modeling and will lead to better understanding of space weather origins. MUSE’s multi-slit coronal spectroscopy will use a 100x improvement in spectral raster cadence to fill a crucial gap in our knowledge of Sun-Earth connections; it will reveal temperatures, velocities and non-thermal processes over a wide temperature range to diagnose physical processes that remain invisible to current or planned instruments. MUSE will contain two instruments: an EUV spectrograph (SG) and EUV context imager (CI). Both have similar spatial resolution and leverage extensive heritage from previous high-resolution instruments such as IRIS and the HiC rocket payload. The MUSE investigation will build on the success of IRIS by combining numerical modeling with a uniquely capable observatory: MUSE will obtain EUV spectra and images with the highest resolution in space (1/3 arcsec) and time (1-4 s) ever achieved for the transition region and corona, along 35 slits and a large context FOV simultaneously. The MUSE consortium includes LMSAL, SAO, Stanford, ARC, HAO, GSFC, MSFC, MSU, ITA Oslo and other institutions.

JWST DD ERS Team Update: Decoding Smoke Signals from WR140 using NIRISS+AMI and MIRI/MRS

NASA Astrophysics Data System (ADS)

Lau, Ryan M.; Hankins, Matt; WR DustERS Team

2018-06-01

Dust is a key component of the interstellar medium and plays and important role in the formation of stars and planets. However, the dominant channels of dust production throughout cosmic time are uncertain. With its unprecedented sensitivity and spatial resolution in the mid-IR, the James Webb Space Telescope (JWST) is the ideal platform to address this issue by investigating the dust abundance, composition, and production rates of various dusty sources. In particular, colliding-wind Wolf-Rayet (WR) binaries are known to be efficient dust producers in the local Universe and likely existed in the earliest galaxies. In our Early Release Science (ERS) program, we will use JWST to observe the archetypal colliding-wind binary, WR 140, to study its dust composition, abundance, and formation mechanisms. We will utilize two key JWST observing modes with the medium-resolution spectrometer (MRS) on the Mid-Infrared Instrument (MIRI) and the Aperture Masking Interferometry (AMI) mode with the Near Infrared Imager and Slitless Spectrograph (NIRISS).Our planned observations will establish a benchmark for key observing modes for imaging bright sources with faint extended emission at high spatial resolutions. This will be valuable in various astrophysical contexts including mass-loss from evolved stars, dusty tori around active galactic nuclei, and protoplanetary disks. We are committed to delivering science-enabling products for the JWST community that include high-level pipeline tools to mitigate bright source artifacts and image reconstruction tools compatible with NIRISS+AMI data.

Single Mode, Extreme Precision Doppler Spectrographs

NASA Astrophysics Data System (ADS)

Schwab, Christian; Leon-Saval, Sergio G.; Betters, Christopher H.; Bland-Hawthorn, Joss; Mahadevan, Suvrath

2014-04-01

The `holy grail' of exoplanet research today is the detection of an earth-like planet: a rocky planet in the habitable zone around a main-sequence star. Extremely precise Doppler spectroscopy is an indispensable tool to find and characterize earth-like planets; however, to find these planets around solar-type stars, we need nearly one order of magnitude better radial velocity (RV) precision than the best current spectrographs provide. Recent developments in astrophotonics (Bland-Hawthorn & Horton 2006, Bland-Hawthorn et al. 2010) and adaptive optics (AO) enable single mode fiber (SMF) fed, high resolution spectrographs, which can realize the next step in precision. SMF feeds have intrinsic advantages over multimode fiber or slit coupled spectrographs: The intensity distribution at the fiber exit is extremely stable, and as a result the line spread function of a well-designed spectrograph is fully decoupled from input coupling conditions, like guiding or seeing variations (Ihle et al. 2010). Modal noise, a limiting factor in current multimode fiber fed instruments (Baudrand & Walker 2001), can be eliminated by proper design, and the diffraction limited input to the spectrograph allows for very compact instrument designs, which provide excellent optomechanical stability. A SMF is the ideal interface for new, very precise wavelength calibrators, like laser frequency combs (Steinmetz et al. 2008, Osterman et al. 2012), or SMF based Fabry-Perot Etalons (Halverson et al. 2013). At near infrared wavelengths, these technologies are ready to be implemented in on-sky instruments, or already in use. We discuss a novel concept for such a spectrograph.

Optical alignment of the Chromospheric Lyman-Alpha Spectro-Polarimeter using sophisticated methods to minimize activities under vacuum

NASA Astrophysics Data System (ADS)

Giono, G.; Katsukawa, Y.; Ishikawa, R.; Narukage, N.; Kano, R.; Kubo, M.; Ishikawa, S.; Bando, T.; Hara, H.; Suematsu, Y.; Winebarger, A.; Kobayashi, K.; Auchère, F.; Trujillo Bueno, J.

2016-07-01

The Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) is a sounding-rocket instrument developed at the National Astronomical Observatory of Japan (NAOJ) as a part of an international collaboration. The instrument main scientific goal is to achieve polarization measurement of the Lyman-α line at 121.56 nm emitted from the solar upper-chromosphere and transition region with an unprecedented 0.1% accuracy. The optics are composed of a Cassegrain telescope coated with a "cold mirror" coating optimized for UV reflection and a dual-channel spectrograph allowing for simultaneous observation of the two orthogonal states of polarization. Although the polarization sensitivity is the most important aspect of the instrument, the spatial and spectral resolutions of the instrument are also crucial to observe the chromospheric features and resolve the Ly-α profiles. A precise alignment of the optics is required to ensure the resolutions, but experiments under vacuum conditions are needed since Ly-α is absorbed by air, making the alignment experiments difficult. To bypass this issue, we developed methods to align the telescope and the spectrograph separately in visible light. We explain these methods and present the results for the optical alignment of the CLASP telescope and spectrograph. We then discuss the combined performances of both parts to derive the expected resolutions of the instrument, and compare them with the flight observations performed on September 3rd 2015.

Habitable Exoplanet Imaging Mission (HabEx): Architecture of the 4m Mission Concept

NASA Astrophysics Data System (ADS)

Kuan, Gary M.; Warfield, Keith R.; Mennesson, Bertrand; Kiessling, Alina; Stahl, H. Philip; Martin, Stefan; Shaklan, Stuart B.; amini, rashied

2018-01-01

The Habitable Exoplanet Imaging Mission (HabEx) study is tasked by NASA to develop a scientifically compelling and technologically feasible exoplanet direct imaging mission concept, with extensive general astrophysics capabilities, for the 2020 Decadal Survey in Astrophysics. The baseline architecture of this space-based observatory concept encompasses an unobscured 4m diameter aperture telescope flying in formation with a 72-meter diameter starshade occulter. This large aperture, ultra-stable observatory concept extends and enhances upon the legacy of the Hubble Space Telescope by allowing us to probe even fainter objects and peer deeper into the Universe in the same ultraviolet, visible, and near infrared wavelengths, and gives us the capability, for the first time, to image and characterize potentially habitable, Earth-sized exoplanets orbiting nearby stars. Revolutionary direct imaging of exoplanets will be undertaken using a high-contrast coronagraph and a starshade imager. General astrophysics science will be undertaken with two world-class instruments – a wide-field workhorse camera for imaging and multi-object grism spectroscopy, and a multi-object, multi-resolution ultraviolet spectrograph. This poster outlines the baseline architecture of the HabEx flagship mission concept.

Investigation of focal ratio degradation in optical fibres for astronomical instrumentation

NASA Astrophysics Data System (ADS)

Crause, Lisa; Bershady, Matthew; Buckley, David

2008-07-01

A differential method was used to investigate the focal ratio degradation (FRD) exhibited by, and throughput of, a selection of current-generation optical fibres. These fibres were tested to establish which would be best suited to feed the High Resolution Spectrograph being built for the Southern African Large Telescope (SALT), as well as for future instruments on WIYN and SALT. The double re-imaging system of Bershady et al. (2004) was substantially modified to improve image quality and measurement efficiency, and to permit a direct FRD-measurement in the far-field. The re-imaging method compares the beam profile produced by light which passes through a fibre to that which does not. Broad and intermediate band-pass filters were used between 400-800 nm to test for wavelength dependence in the observed FRD over a wide range in beam-speeds. Our results continue to be at odds with a mico-bend model for FRD. We conclude that the new Polymicro FBP fibre is the most suitable product for broadband applications.

Second Announcement - ESO/ST-ECF Workshop on NICMOS and the VLT: A New Era of High-Resolution Near-Infrared Imaging and Spectroscopy - May 26-27, 1998 - Hotel Baia di Nora, Pula, Sardinia, Italy

NASA Astrophysics Data System (ADS)

1998-03-01

ST-ECF and ESO are organising in collaboration with the NICMOS IDT and STScI a workshop on near infrared imaging from space and ground. The purpose of the workshop is to review what has been achieved with the Near Infrared and Multi Object Spectrograph (NICMOS) on board of HST, what can be achieved in the remaining lifetime of the instrument, and how NICMOS observations can be optimised taking into account the availability of IR imaging and spectroscopy on ESO's Very large Telescope (VLT) in the near future. The meeting will be held in May 1998, about one year after science observations started with NICMOS, and about half a year before the Infrared Spectrometer and Array Camera (ISAAC) starts to operate on the VLT. Currently, it is expected that NICMOS will operate until the end of 1998.

Estado y rendimiento del espectrógrafo infrarrojo criogénico F2

NASA Astrophysics Data System (ADS)

Diaz, R. J.; Gomez, P.; Schirmer, M.; Navarrete, F.; Stephens, A.; Bosch, G.; Gaspar, G.; Camperi, J.; Gunthardt, G.

First results related to the commissioning phase of Flamingos-2 spectrograph are reported. The available operation modes for observation and expected performance for 2014 are also presented. After the replacement of the first collimator lens; broken in 2012; a problem persisted in the optical alignment. The troubleshooting will require a new instrument refurbishing schedule; meanwhile; the available operation modes are limited to direct image and longslit spectroscopy. We found that the direct image () achieves its highest quality (0.4'') only in the inner 3' of the field and resolution drops toward the spectrum ends. The longslit mode provides for the / ranges; and for the R3k grism in the ranges ; or . We also determine the uncertainties for emission line kinematics; and study the relative flexion between the guiding system; the slit and the detector. FULL TEXT IN SPANISH

NASA's IRIS Observed a Gigantic Eruption on the Sun!

NASA Image and Video Library

2014-05-30

A coronal mass ejection, or CME, surged off the side of the sun on May 9, 2014, and NASA's newest solar observatory caught it in extraordinary detail. This was the first CME observed by the Interface Region Imaging Spectrograph, or IRIS, which launched in June 2013 to peer into the lowest levels of the sun's atmosphere with better resolution than ever before. Watch the movie to see how a curtain of solar material erupts outward at speeds of 1.5 million miles per hour. Read more: 1.usa.gov/1kp7O4F Credit: NASA's Goddard Space Flight Center NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

The optical design of solar spectrograph

NASA Astrophysics Data System (ADS)

Zhang, Yang; Pan, Wen-Qiang; Meng, Xiang-Yue; Lv, Xian-Kui; Feng, Jie; Zhu, Jia-Wei; Zhang, Xiao-Xiao; Li, Lei; Yang, Wei-Ping

2017-08-01

At the beginning of this paper, we simply describe the theories of spectrograph and the operating principle of grating. Based on the Spectrometer theory and optical theory we design a solar spectrograph by analyzing and calculating. And the working waveband of this solar spectrograph is between 510nm and 540nm. Besides, according to the design data, we ensure the blaze level of grating and the focal length of collimate. Due to the presence of the collimate in the optical structure, astigmatism exists in the system. For this reason, we add a cylindrical lens to the structure to correct. The optical system is characterized by using white-pupil design and folding light path to make the whole system simple. In the end, according to the calculated design parameters, we use the Zemax software for simulation, then the result is RMS only has 4μm at the 520nm. It's worth nothing that the resolution merely near the reference wavelength (520nm)meets the design requirements.

VizieR Online Data Catalog: Radial velocity follow-up of the HD 3167 system (Gandolfi+, 2017)

NASA Astrophysics Data System (ADS)

Gandolfi, D.; Barragan, O.; Hatzes, A. P.; Fridlund, M.; Fossati, L.; Donati, P.; Johnson, M. C.; Nowak, G.; Prieto-Arranz, J.; Albrecht, S.; Dai, F.; Deeg, H.; Endl, M.; Grziwa, S.; Hjorth, M.; Korth, J.; Nespral, D.; Saario, J.; Smith, A. M. S.; Antoniciello, G.; Alarcon, J.; Bedell, M.; Blay, P.; Brems, S. S.; Cabrera, J.; Csizmadia, S.; Cusano, F.; Cochran, W. D.; Eigmuller, P.; Erikson, A.; Gonzalez Hernandez, J. I.; Guenther, E. W.; Hirano, T.; Suarez Mascareno, A.; Narita, N.; Palle, E.; Parviainen, H.; Patzold, M.; Persson, C. M.; Rauer, H.; Saviane, I.; Schmidtobreick, L.; van Eylen, V.; Winn, J. N.; Zakhozhay, O. V.

2018-06-01

We used the FIbre-fed Echelle Spectrograph (FIES; Frandsen & Lindberg 1999anot.conf...71F; Telting et al. 2014AN....335...41T) mounted at the 2.56 m Nordic Optical Telescope (NOT) of Roque de los Muchachos Observatory (La Palma, Spain) to acquire 37 high-resolution spectra (R~67000) in 12 different nights between July and September 2016. We also acquired 50 spectra with the HARPS spectrograph (R~115000; Mayor et al. 2003Msngr.114...20M) and 32 spectra with the HARPS-N spectrograph (R~115000; Cosentino et al. 2012SPIE.8446E..1VC). HARPS and HARPS-N are fiber-fed cross-dispersed echelle spectrographs specifically designed to achieve very high-precision long-term RV stabilities (<1 m/s). They are mounted at the ESO-3.6 m telescope of La Silla observatory (Chile) and at the 3.58 m Telescopio Nazionale Galileo (TNG) of Roque de los Muchachos Observatory (La Palma, Spain). (1 data file).

Medium Resolution Spectroscopy of Boyajian's Star (KIC 8462852)

NASA Astrophysics Data System (ADS)

Steele, I. A.; Lamb, G. P.; Copperwheat, C. M.; Jermak, H. E.

2017-05-01

ATel #10405 reports that a several percent dip in the brightness of KIC 8462852 is underway. We report medium resolution spectroscopy (R=2500) taken with the FRODOSpec fibre fed integral field spectrograph of the 2.0 meter Liverpool Telescope, La Palma obtained on 20th May 2017 starting at 01:20UT.

Temporal intensity interferometry for characterization of very narrow spectral lines

NASA Astrophysics Data System (ADS)

Tan, P. K.; Kurtsiefer, C.

2017-08-01

Some stellar objects exhibit very narrow spectral lines in the visible range additional to their blackbody radiation. Natural lasing has been suggested as a mechanism to explain narrow lines in Wolf-Rayet stars. However, the spectral resolution of conventional astronomical spectrographs is still about two orders of magnitude too low to test this hypothesis. We want to resolve the linewidth of narrow spectral emissions in starlight. A combination of spectral filtering with single-photon-level temporal correlation measurements breaks the resolution limit of wavelength-dispersing spectrographs by moving the linewidth measurement into the time domain. We demonstrate in a laboratory experiment that temporal intensity interferometry can determine a 20-MHz-wide linewidth of Doppler-broadened laser light and identify a coherent laser light contribution in a blackbody radiation background.

Technical aspects of the Space Telescope Imaging Spectrograph Repair (STIS-R)

NASA Astrophysics Data System (ADS)

Rinehart, S. A.; Domber, J.; Faulkner, T.; Gull, T.; Kimble, R.; Klappenberger, M.; Leckrone, D.; Niedner, M.; Proffitt, C.; Smith, H.; Woodgate, B.

2008-07-01

In August 2004, the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) ceased operation due to a failure of the 5V mechanism power converter in the Side 2 Low Voltage Power Supply (LVPS2). The failure precluded movement of any STIS mechanism and, because of the earlier (2001) loss of the Side 1 electronics chain, left the instrument shuttered and in safe mode after 7.5 years of science operations. A team was assembled to analyze the fault and to determine if STIS repair (STIS-R) was feasible. The team conclusively pinpointed the Side 2 failure to the 5V mechanism converter, and began studying EVA techniques for opening STIS during Servicing Mission 4 (SM4) to replace the failed LVPS2 board. The restoration of STIS functionality via surgical repair by astronauts has by now reached a mature and final design state, and will, along with a similar repair procedure for the Advanced Camera for Surveys (ACS), represent a first for Hubble servicing. STIS-R will restore full scientific functionality of the spectrograph on Side 2, while Side 1 will remain inoperative. Because of the high degree of complementarity between STIS and the new Cosmic Origins Spectrograph (COS, to be installed during SM4)), successful repair of the older spectrograph is an important scientific objective. In this presentation, we focus on the technical aspects associated with STIS-R.

VizieR Online Data Catalog: Abundances in the local region. II. F, G, and K dwarfs (Luck+, 2017)

NASA Astrophysics Data System (ADS)

Luck, R. E.

2017-06-01

The McDonald Observatory 2.1m Telescope and Sandiford Cassegrain Echelle Spectrograph provided much of the observational data for this study. High-resolution spectra were obtained during numerous observing runs, from 1996 to 2010. The spectra cover a continuous wavelength range from about 484 to 700nm, with a resolving power of about 60000. The wavelength range used demands two separate observations--one centered at about 520nm, and the other at about 630nm. Typical S/N values per pixel for the spectra are more than 150. Spectra of 57 dwarfs were obtained using the Hobby-Eberly telescope and High-Resolution Spectrograph. The spectra have a resolution of 30000, spanning the wavelength range of 400 to 785nm. They also have very high signal-to-noise ratios, >300 per resolution element in numerous cases. The last set of spectra were obtained from the ELODIE Archive (Moultaka et al. 2004PASP..116..693M). These spectra are fully processed, including order co-addition, and have a continuous wavelength span of 400 to 680nm and a resolution of 42000. The ELODIE spectra utilized here all have S/N>75 per pixel. (6 data files).

SOAR Optical Imager (SOI) | SOAR

Science.gov Websites

SPARTAN Near-IR Camera Ohio State Infrared Imager/Spectrograph (OSIRIS) - NO LONGER AVAILABLE SOAR ?: ADS link to SOI instrument SPIE paper Last update: C. Briceño, Aug 23, 2017 SOAR Optical Imager

Using confidence intervals to evaluate the focus alignment of spectrograph detector arrays.

PubMed

Sawyer, Travis W; Hawkins, Kyle S; Damento, Michael

2017-06-20

High-resolution spectrographs extract detailed spectral information of a sample and are frequently used in astronomy, laser-induced breakdown spectroscopy, and Raman spectroscopy. These instruments employ dispersive elements such as prisms and diffraction gratings to spatially separate different wavelengths of light, which are then detected by a charge-coupled device (CCD) or complementary metal-oxide-semiconductor (CMOS) detector array. Precise alignment along the optical axis (focus position) of the detector array is critical to maximize the instrumental resolution; however, traditional approaches of scanning the detector through focus lack a quantitative measure of precision, limiting the repeatability and relying on one's experience. Here we propose a method to evaluate the focus alignment of spectrograph detector arrays by establishing confidence intervals to measure the alignment precision. We show that propagation of uncertainty can be used to estimate the variance in an alignment, thus providing a quantitative and repeatable means to evaluate the precision and confidence of an alignment. We test the approach by aligning the detector array of a prototype miniature echelle spectrograph. The results indicate that the procedure effectively quantifies alignment precision, enabling one to objectively determine when an alignment has reached an acceptable level. This quantitative approach also provides a foundation for further optimization, including automated alignment. Furthermore, the procedure introduced here can be extended to other alignment techniques that rely on numerically fitting data to a model, providing a general framework for evaluating the precision of alignment methods.

Total Solar Eclipse to Introduce Scientific Research

NASA Astrophysics Data System (ADS)

Choudhary, D. P.

2015-12-01

We are designing an experiment to record time lapse slit-less flash spectra of solar chromosphere and corona before, during and after the Total Solar Eclipse (TSE). As the moon gradually covers different heights of chromosphere and corona, the time lapse spectra would provide high hight-resolution information about the line formation starting at very close proximity to the solar limb. The flash spectrum will be recored with a slit-less spectrograph consisting of a transmission grating of 300 lines/mm, blazed at 5000 Å, and an 135 mm f/3.5 telephoto lens. Based on earlier such instruments, the system's efficiency is expected to be about 60% at 5303 Å (Fe XIV emission line) and 20% at 6374 Å (Fe X emission line) (Voulgaris, 2010). We shall place the grating before the telephoto lens on a wedge shaped. The full range of the visible spectrum, from 3900 Å to 6700 Å will be projected on the CCD sensor of the digital camera. The resolution of the spectrograph is expected to be 0.5 Å/pixel at 5215 Å. The diameter of the Sun would corresponded to 275 pixels or 6.87''/pixel. By turning the grating, the direction of the ruling shall be set parallel to the direction of the last visible elongated crescent of the Sun; which will play the role of the "slit" in the slitless spectrograph. The spectrograph will be mounted on a solar tracker to observe the sun during TSE.

Hartmann wavefront sensing of the corrective optics for the Hubble Space Telescope

NASA Astrophysics Data System (ADS)

Davila, Pam S.; Eichhorn, William L.; Wilson, Mark E.

1994-06-01

There is no doubt that astronomy with the `new, improved' Hubble Space Telescope will significantly advance our knowledge and understanding of the universe for years to come. The Corrective Optics Space Telescope Axial Replacement (COSTAR) was designed to restore the image quality to nearly diffraction limited performance for three of the first generation instruments; the faint object camera, the faint object spectrograph, and the Goddard high resolution spectrograph. Spectacular images have been obtained from the faint object camera after the installation of the corrective optics during the first servicing mission in December of 1993. About 85% of the light in the central core of the corrected image is contained within a circle with a diameter of 0.2 arcsec. This is a vast improvement over the previous 15 to 17% encircled energies obtained before COSTAR. Clearly COSTAR is a success. One reason for the overwhelming success of COSTAR was the ambitious and comprehensive test program conducted by various groups throughout the program. For optical testing of COSTAR on the ground, engineers at Ball Aerospace designed and built the refractive Hubble simulator to produce known amounts of spherical aberration and astigmatism at specific points in the field of view. The design goal for this refractive aberrated simulator (RAS) was to match the aberrations of the Hubble Space Telescope to within (lambda) /20 rms over the field at a wavelength of 632.8 nm. When the COSTAR optics were combined with the RAS optics, the corrected COSTAR output images were produced. These COSTAR images were recorded with a high resolution 1024 by 1024 array CCD camera, the Ball image analyzer (BIA). The image quality criteria used for assessment of COSTAR performance was encircled energy in the COSTAR focal plane. This test with the BIA was very important because it was a direct measurement of the point spread function. But it was difficult with this test to say anything quantitative about the aberration content of the corrected images. Also, from only this test it was difficult to measure important pupil parameters, such as pupil intensity profiles and pupil sizes and location. To measure the COSTAR wavefront accurately and to determine pupil parameters, another very important test was performed on the COSTAR optics. A Hartmann test of the optical system consisting of the RAS and COSTAR was conducted by the Goddard Independent Verification Team (IVT). In this paper, we first describe the unique Hartmann sensor that was developed by the IVT. Then we briefly describe the RAS and COSTAR optical systems and the test setup. Finally, we present the results of the test and compare our results with results obtained from optical analysis and from image tests with the BIA.

VizieR Online Data Catalog: Astrometry and photometry of nearby white dwarfs (Limoges+, 2013)

NASA Astrophysics Data System (ADS)

Limoges, M.-M.; Lepine, S.; Bergeron, P.

2014-06-01

Optical spectra have been obtained with the Steward Observatory 2.3m telescope and the B&C spectrograph on 2009 May, 2009 Nov, 2010 July, with the NOAO Mayall 4m telescope and the RC spectrograph on 2009 Aug, 2010 Mar, 2010 Oct, and with the NOAO 2.1m and the Goldcam spectrograph on 2009 Dec, 2010 May. The adopted configurations allow a spectral coverage of λλ3800-5600 and λλ3800-6700, at an intermediate resolution of ~6ÅFWHM. Spectra were first obtained at low signal-to-noise ratio (S/N ~25). As a result of our spectroscopic observations, 193 newly identified white dwarfs from the SUPERBLINK catalog have been spectroscopically confirmed (Tables 3 and 4). (3 data files).

The Hubble Space Telescope: UV, Visible, and Near-Infrared Pursuits

NASA Technical Reports Server (NTRS)

Wiseman, Jennifer

2010-01-01

The Hubble Space Telescope continues to push the limits on world-class astrophysics. Cameras including the Advanced Camera for Surveys and the new panchromatic Wide Field Camera 3 which was installed nu last year's successful servicing mission S2N4,o{fer imaging from near-infrared through ultraviolet wavelengths. Spectroscopic studies of sources from black holes to exoplanet atmospheres are making great advances through the versatile use of STIS, the Space Telescope Imaging Spectrograph. The new Cosmic Origins Spectrograph, also installed last year, is the most sensitive UV spectrograph to fly io space and is uniquely suited to address particular scientific questions on galaxy halos, the intergalactic medium, and the cosmic web. With these outstanding capabilities on HST come complex needs for laboratory astrophysics support including atomic and line identification data. I will provide an overview of Hubble's current capabilities and the scientific programs and goals that particularly benefit from the studies of laboratory astrophysics.

The SALT HRS Spectrograph

NASA Astrophysics Data System (ADS)

Tyas, Luke Martin Graham

2012-05-01

SALT HRS (Southern African Large Telescope High Resolution Échelle Spectrograph) is a high-resolution, high-efficiency spectrograph for the 11m SALT telescope in Sutherland, South Africa. The initial optical design work was performed at the University of Canterbury, New Zealand. Revisions to the concept, the mechanical design, manufacture, assembly and testing have been handled by the Centre for Advanced Instrumentation, at Durham University in the United Kingdom. SALT HRS is a fibre-fed échelle grating spectrograph with four operational modes: low-, medium- and high-resolution and high-stability modes, having spectral resolutions of R≈16000, 37000, 67000 and 67000 respectively over a wavelength range of 370-890nm. The instrument is of a dual channel, 'white pupil' design, in which the primary mirror acts to collimate light onto a single R4 échelle grating, and also to focus dispersed light to an intermediate focus. A dichroic beam-splitter separates the dispersed light into two separate spectral channels. Spherical pupil mirrors transfer the separated beams via a fold mirror to two wavelength-specific volume-phase holographic gratings (VPHGs) used as cross-dispersers. Cross-dispersed spectra are then imaged by two fully dioptric camera systems onto optimized CCD detectors. This thesis presents the results of the laboratory testing and specification of several critical sub-systems of SALT HRS, as well as the development of key software tools for the design verification and operation at the telescope. In Chapter 1 we first review the technical development of high-resolution spectroscopy and its specific implementation in SALT HRS. In Chapter 2 we develop a comprehensive throughput model of the entire system based on a combination of as-built performance and specific throughput measurements in the laboratory. This is used to make some specific predictions for the on-sky performance of SALT HRS and the magnitude limits for science targets. We also present a graphical exposure time calculator based on these measurements which can be used by an astronomer to plan their observations with SALT HRS. Chapter 3 contains a detailed treatise on the optical fibre system of SALT HRS. Considerations for the use of optical fibres in astronomy are provided, as are details of an optional double scrambler, and the various instrument fibre modes. Extensive measurements of focal ratio degradation (FRD) are also presented, with testing of input beam speed; wavelength; fibre bending; variable pupil mirror illumination; and vacuum tank pressure dependency. The systems for fibre management are reviewed, as is the fibre bundle assembly process. Testing of two further sub-systems is described in Chapter 4. Firstly the long-term stability of the mirror mounting mechanisms is determined. The advantages of cross-dispersion of échelle spectra using volume-phase holographic gratings are then discussed, and the results of diffraction efficiency measurements are given for both red and blue channel gratings. Modern CCD technologies are examined in Chapter 5, and the blue detector is experimentally characterized using photon transfer and quantum efficiency curves. It is also used for an investigation into cosmic ray events in CCDs. Results from shielding the detector using lead are described, as is an attempt to distinguish the source of the events based on their morphology. Finally, Chapter 6 deals with the handling of data produced by SALT HRS. Methods of wavelength calibration of the spectra are discussed, including the use of Thorium-Argon lamps and an iodine absorption cell. The implementation of a Python based quick-look data reduction pipeline is reviewed, with a description of the processes performed. A summary of the thesis is given in Chapter 7.

Development of the fibres of MOONS

NASA Astrophysics Data System (ADS)

Guinouard, Isabelle; Lee, David; Schnetler, Hermine; Taylor, William; Amans, Jean-Philippe; Montgomery, David; Oliva, Ernesto

2014-07-01

MOONS will exploit the full 500 square arcmin field of view offered by the Nasmyth focus of the Very Large Telescope and will be equipped with two identical triple arm cryogenic spectrographs covering the wavelength range 0.8 - 1.8 μm, with a multiplex capability of approximately 1000 fibres. Each triple arm spectrograph will produce spectra for half of the targets simultaneously. The system will have both a medium resolution (R~4000-6000) mode and a high resolution (R~20000) mode. The fibres are used to pick off each sub field of 1.05 arcseconds and are used to transport the light from the instrument focal plane to the two spectrographs. Each fibre has a microlens to focus the beam into the fibre at a relative fast focal ratio of F/3.65 to reduce the Focal Ratio Degradation (FRD). This paper presents the overall design of the fibre system and describes the specific developments required to optimise its performance. The design of the fibre input optics, the choice of the fibre connector, and the layout of the slit end are described. The results of preliminary tests to measure the effect of twisting on the FRD performance of prototype fibres are also discussed.

Affordable spectroscopy for 1m-class telescopes: recent developments and applications

NASA Astrophysics Data System (ADS)

Csák, B.; Kovács, J.; Szabó, Gy. M.; Kiss, L. L.; Dózsa, Á.; Sódor, Á.; Jankovics, I.

2014-03-01

Doppler observations of exoplanet systems have been a very expensive technique, mainly due to the high costs of high-resolution stable spectrographs. Recent advances in instrumentation enable affordable Doppler planet detections with surprisingly small optical telescopes. We investigate the possibility of measuring Doppler reflex motion of planet hosting stars with small-aperture telescopes that have traditionally been neglected for this kind of studies. After thoroughly testing the recently developed and commercially available Shelyak eShel echelle spectrograph, we demonstrated that it is routinely possible to achieve velocity precision at the 100 m s-1 level, reaching down to ¬± 50 m s-1 for the best cases. We describe our off-the-shelf instrumentation, including a new 0.5m RC telescope at the Gothard Astrophysical Observatory of Loránd E&ötv&ös University equipped with an intermediate resolution fiber-fed echelle spectrograph. We present some follow-up radial velocity measurements of planet hosting stars and point out that updating the orbital solution of Doppler-planets is a very important task that can be fulfilled with sub-meter sized optical telescopes without requesting very expensive telescope times on 2—4 m (or larger) class telescopes.

VizieR Online Data Catalog: H-band spectroscopic analysis of 25 bright M31 GCs (Sakari+, 2016)

NASA Astrophysics Data System (ADS)

Sakari, C. M.; Shetrone, M. D.; Schiavon, R. P.; Bizyaev, D.; Prieto, C. A.; Beers, T. C.; Caldwell, N.; Garcia-Hernandez, D. A.; Lucatello, S.; Majewski, S.; O'Connell, R. W.; Pan, K.; Strader, J.

2016-11-01

H-band spectra (1.51-1.69um) of the target clusters were obtained with the moderately high resolution (R=22500) APOGEE spectrograph on the 2.5m Telescope at Apache Point Observatory in 2011 and 2013. The details of the observations can be found in Majewski+ (2015arXiv150905420M) and Zasowski+ (2013AJ....146...81Z), including descriptions of the plates and fibers that were utilized for the observations. The high-resolution optical abundances from Colucci et al. (2009, J/ApJ/704/385 and 2014ApJ...797..116C) are supplemented with new results for five globular clusters (GCs). The new optical spectra were obtained in 2009 and 2010 with the High Resolution Spectrograph on the Hobby-Eberly Telescope at McDonald Observatory in Fort Davis, TX (R=30000; spectral coverage over ~5320-6290 and ~6360-7340Å in the blue and the red, respectively). (5 data files).

FISICA: The Florida Image Slicer for Infrared Astrophysics and Cosmology

NASA Astrophysics Data System (ADS)

Raines, S. N.; Eikenberry, S. S.; Elston, R.; Guzman, R.; Gruel, N.; Julian, J.; Boreman, G.; Hoffman, J.; Rodgers, M.; Glenn, P.; Hull-Allen, G.; Myrick, B.; Flint, S.; Comstock, L.

2005-12-01

We report on the design, manufacture, and scientific performance of the Florida Image Slicer for Infrared Astrophysics and Cosmology (FISICA) - a fully cryogenic all-reflective image slicing integral field unit for the FLAMINGOS near-infrared spectrograph. Originally conceived as a bench-top demonstration proof-of-concept instrument, after three productive engineering runs at the KPNO 4-m telescope (as of 15 Oct 2005) we find that FISICA is capable of delivering excellent scientific results. It now operates as a 'turnkey' instrument at the KPNO 4-m telescope. FISICA is now open for community access as a visitor instrument on the KPNO 4-m telescope via collaboration with the instrument team, who can assist with the proposal preparation and observations, as well as provide the data reduction tools for integral field spectroscopy. We review the optical and opto-mechanical design, fabrication, laboratory test results, and on-telescope performance for FISICA. Designed to accept input beams near f/15, FISICA with FLAMINGOS slices a 16x33 arcsec field of view into 22 parallel elements using three sets of monolithic powered mirror arrays, each with 22 mirrored surfaces cut into a single piece of aluminum. However, slight vignetting for some field positions limits the effective field of view to 15x32 arcsec. The effective spatial sampling of 0.70 arcsec delivers 960 spatial resolution elements. Combined with the FLAMINGOS spectrograph, R 1300 spectroscopy over the 1-2.4 micron wavelength range is possible, in either the J+H combined bandpass or the H+K combined bandpass. FISICA was funded by the UCF-UF Space Research Initiative; FLAMINGOS was designed and was constructed by the IR Instrumentation Group (PI: R. Elston) at the University of Florida, Department of Astronomy, with support from NSF grant AST97-31180 and Kitt Peak National Observatory.

The Eleventh and Twelfth Data Releases of the Sloan Digital Sky Survey: Final Data from SDSS-III

NASA Astrophysics Data System (ADS)

Alam, Shadab; Albareti, Franco D.; Allende Prieto, Carlos; Anders, F.; Anderson, Scott F.; Anderton, Timothy; Andrews, Brett H.; Armengaud, Eric; Aubourg, Éric; Bailey, Stephen; Basu, Sarbani; Bautista, Julian E.; Beaton, Rachael L.; Beers, Timothy C.; Bender, Chad F.; Berlind, Andreas A.; Beutler, Florian; Bhardwaj, Vaishali; Bird, Jonathan C.; Bizyaev, Dmitry; Blake, Cullen H.; Blanton, Michael R.; Blomqvist, Michael; Bochanski, John J.; Bolton, Adam S.; Bovy, Jo; Shelden Bradley, A.; Brandt, W. N.; Brauer, D. E.; Brinkmann, J.; Brown, Peter J.; Brownstein, Joel R.; Burden, Angela; Burtin, Etienne; Busca, Nicolás G.; Cai, Zheng; Capozzi, Diego; Carnero Rosell, Aurelio; Carr, Michael A.; Carrera, Ricardo; Chambers, K. C.; Chaplin, William James; Chen, Yen-Chi; Chiappini, Cristina; Chojnowski, S. Drew; Chuang, Chia-Hsun; Clerc, Nicolas; Comparat, Johan; Covey, Kevin; Croft, Rupert A. C.; Cuesta, Antonio J.; Cunha, Katia; da Costa, Luiz N.; Da Rio, Nicola; Davenport, James R. A.; Dawson, Kyle S.; De Lee, Nathan; Delubac, Timothée; Deshpande, Rohit; Dhital, Saurav; Dutra-Ferreira, Letícia; Dwelly, Tom; Ealet, Anne; Ebelke, Garrett L.; Edmondson, Edward M.; Eisenstein, Daniel J.; Ellsworth, Tristan; Elsworth, Yvonne; Epstein, Courtney R.; Eracleous, Michael; Escoffier, Stephanie; Esposito, Massimiliano; Evans, Michael L.; Fan, Xiaohui; Fernández-Alvar, Emma; Feuillet, Diane; Filiz Ak, Nurten; Finley, Hayley; Finoguenov, Alexis; Flaherty, Kevin; Fleming, Scott W.; Font-Ribera, Andreu; Foster, Jonathan; Frinchaboy, Peter M.; Galbraith-Frew, J. G.; García, Rafael A.; García-Hernández, D. A.; García Pérez, Ana E.; Gaulme, Patrick; Ge, Jian; Génova-Santos, R.; Georgakakis, A.; Ghezzi, Luan; Gillespie, Bruce A.; Girardi, Léo; Goddard, Daniel; Gontcho, Satya Gontcho A.; González Hernández, Jonay I.; Grebel, Eva K.; Green, Paul J.; Grieb, Jan Niklas; Grieves, Nolan; Gunn, James E.; Guo, Hong; Harding, Paul; Hasselquist, Sten; Hawley, Suzanne L.; Hayden, Michael; Hearty, Fred R.; Hekker, Saskia; Ho, Shirley; Hogg, David W.; Holley-Bockelmann, Kelly; Holtzman, Jon A.; Honscheid, Klaus; Huber, Daniel; Huehnerhoff, Joseph; Ivans, Inese I.; Jiang, Linhua; Johnson, Jennifer A.; Kinemuchi, Karen; Kirkby, David; Kitaura, Francisco; Klaene, Mark A.; Knapp, Gillian R.; Kneib, Jean-Paul; Koenig, Xavier P.; Lam, Charles R.; Lan, Ting-Wen; Lang, Dustin; Laurent, Pierre; Le Goff, Jean-Marc; Leauthaud, Alexie; Lee, Khee-Gan; Lee, Young Sun; Licquia, Timothy C.; Liu, Jian; Long, Daniel C.; López-Corredoira, Martín; Lorenzo-Oliveira, Diego; Lucatello, Sara; Lundgren, Britt; Lupton, Robert H.; Mack, Claude E., III; Mahadevan, Suvrath; Maia, Marcio A. G.; Majewski, Steven R.; Malanushenko, Elena; Malanushenko, Viktor; Manchado, A.; Manera, Marc; Mao, Qingqing; Maraston, Claudia; Marchwinski, Robert C.; Margala, Daniel; Martell, Sarah L.; Martig, Marie; Masters, Karen L.; Mathur, Savita; McBride, Cameron K.; McGehee, Peregrine M.; McGreer, Ian D.; McMahon, Richard G.; Ménard, Brice; Menzel, Marie-Luise; Merloni, Andrea; Mészáros, Szabolcs; Miller, Adam A.; Miralda-Escudé, Jordi; Miyatake, Hironao; Montero-Dorta, Antonio D.; More, Surhud; Morganson, Eric; Morice-Atkinson, Xan; Morrison, Heather L.; Mosser, Benôit; Muna, Demitri; Myers, Adam D.; Nandra, Kirpal; Newman, Jeffrey A.; Neyrinck, Mark; Nguyen, Duy Cuong; Nichol, Robert C.; Nidever, David L.; Noterdaeme, Pasquier; Nuza, Sebastián E.; O'Connell, Julia E.; O'Connell, Robert W.; O'Connell, Ross; Ogando, Ricardo L. C.; Olmstead, Matthew D.; Oravetz, Audrey E.; Oravetz, Daniel J.; Osumi, Keisuke; Owen, Russell; Padgett, Deborah L.; Padmanabhan, Nikhil; Paegert, Martin; Palanque-Delabrouille, Nathalie; Pan, Kaike; Parejko, John K.; Pâris, Isabelle; Park, Changbom; Pattarakijwanich, Petchara; Pellejero-Ibanez, M.; Pepper, Joshua; Percival, Will J.; Pérez-Fournon, Ismael; P´rez-Ra`fols, Ignasi; Petitjean, Patrick; Pieri, Matthew M.; Pinsonneault, Marc H.; Porto de Mello, Gustavo F.; Prada, Francisco; Prakash, Abhishek; Price-Whelan, Adrian M.; Protopapas, Pavlos; Raddick, M. Jordan; Rahman, Mubdi; Reid, Beth A.; Rich, James; Rix, Hans-Walter; Robin, Annie C.; Rockosi, Constance M.; Rodrigues, Thaíse S.; Rodríguez-Torres, Sergio; Roe, Natalie A.; Ross, Ashley J.; Ross, Nicholas P.; Rossi, Graziano; Ruan, John J.; Rubiño-Martín, J. A.; Rykoff, Eli S.; Salazar-Albornoz, Salvador; Salvato, Mara; Samushia, Lado; Sánchez, Ariel G.; Santiago, Basílio; Sayres, Conor; Schiavon, Ricardo P.; Schlegel, David J.; Schmidt, Sarah J.; Schneider, Donald P.; Schultheis, Mathias; Schwope, Axel D.; Scóccola, C. G.; Scott, Caroline; Sellgren, Kris; Seo, Hee-Jong; Serenelli, Aldo; Shane, Neville; Shen, Yue; Shetrone, Matthew; Shu, Yiping; Silva Aguirre, V.; Sivarani, Thirupathi; Skrutskie, M. F.; Slosar, Anže; Smith, Verne V.; Sobreira, Flávia; Souto, Diogo; Stassun, Keivan G.; Steinmetz, Matthias; Stello, Dennis; Strauss, Michael A.; Streblyanska, Alina; Suzuki, Nao; Swanson, Molly E. C.; Tan, Jonathan C.; Tayar, Jamie; Terrien, Ryan C.; Thakar, Aniruddha R.; Thomas, Daniel; Thomas, Neil; Thompson, Benjamin A.; Tinker, Jeremy L.; Tojeiro, Rita; Troup, Nicholas W.; Vargas-Magaña, Mariana; Vazquez, Jose A.; Verde, Licia; Viel, Matteo; Vogt, Nicole P.; Wake, David A.; Wang, Ji; Weaver, Benjamin A.; Weinberg, David H.; Weiner, Benjamin J.; White, Martin; Wilson, John C.; Wisniewski, John P.; Wood-Vasey, W. M.; Ye`che, Christophe; York, Donald G.; Zakamska, Nadia L.; Zamora, O.; Zasowski, Gail; Zehavi, Idit; Zhao, Gong-Bo; Zheng, Zheng; Zhou, Xu; Zhou, Zhimin; Zou, Hu; Zhu, Guangtun

2015-07-01

The third generation of the Sloan Digital Sky Survey (SDSS-III) took data from 2008 to 2014 using the original SDSS wide-field imager, the original and an upgraded multi-object fiber-fed optical spectrograph, a new near-infrared high-resolution spectrograph, and a novel optical interferometer. All of the data from SDSS-III are now made public. In particular, this paper describes Data Release 11 (DR11) including all data acquired through 2013 July, and Data Release 12 (DR12) adding data acquired through 2014 July (including all data included in previous data releases), marking the end of SDSS-III observing. Relative to our previous public release (DR10), DR12 adds one million new spectra of galaxies and quasars from the Baryon Oscillation Spectroscopic Survey (BOSS) over an additional 3000 deg2 of sky, more than triples the number of H-band spectra of stars as part of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE), and includes repeated accurate radial velocity measurements of 5500 stars from the Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS). The APOGEE outputs now include the measured abundances of 15 different elements for each star. In total, SDSS-III added 5200 deg2 of ugriz imaging; 155,520 spectra of 138,099 stars as part of the Sloan Exploration of Galactic Understanding and Evolution 2 (SEGUE-2) survey; 2,497,484 BOSS spectra of 1,372,737 galaxies, 294,512 quasars, and 247,216 stars over 9376 deg2; 618,080 APOGEE spectra of 156,593 stars; and 197,040 MARVELS spectra of 5513 stars. Since its first light in 1998, SDSS has imaged over 1/3 of the Celestial sphere in five bands and obtained over five million astronomical spectra.

Beyond MOS and fibers: Optical Fourier-transform Imaging Unit for Cananea Observatory (OFIUCO)

NASA Astrophysics Data System (ADS)

Nieto-Suárez, M. A.; Rosales-Ortega, F. F.; Castillo, E.; García, P.; Escobedo, G.; Sánchez, S. F.; González, J.; Iglesias-Páramo, J.; Mollá, M.; Chávez, M.; Bertone, E.; et al.

2017-11-01

Many physical processes in astronomy are still hampered by the lack of spatial and spectral resolution, and also restricted to the field-of-view (FoV) of current 2D spectroscopy instruments available worldwide. It is due to that, many of the ongoing or proposed studies are based on large-scale imaging and/or spectroscopic surveys. Under this philosophy, large aperture telescopes are dedicated to the study of intrinsically faint and/or distance objects, covering small FoVs, with high spatial resolution, while smaller telescopes are devoted to wide-field explorations. However, future astronomical surveys, should be addressed by acquiring un-biases, spatially resolved, high-quality spectroscopic information for a wide FoV. Therefore, and in order to improve the current instrumental offer in the Observatorio Astrofísico Guillermo Haro (OAGH) in Cananea, Mexico (INAOE); and to explore a possible instrument for the future Telescopio San Pedro Mártir (6.5m), we are currently integrating at INAOE an instrument prototype that will provide us with un-biased wide-field (few arcmin) spectroscopic information, and with the flexibility of operating at different spectral resolutions (R 1-20000), with a spatial resolution limited by seeing, and therefore, to be used in a wide range of astronomical problems. This instrument called OFIUCO: Optical Fourier-transform Imaging Unit for Cananea Observatory, will make use of the Fourier Transform Spectroscopic technique, which has been proved to be feasible in the optical wavelength range (350-1000 nm) with designs such as SITELLE (CFHT). We describe here the basic technical description of a Fourier transform spectrograph with important modifications from previous astronomical versions, as well as the technical advantages and weakness, and the science cases in which this instrument can be implemented.

Development of micro-mirror slicer integral field unit for space-borne solar spectrographs

NASA Astrophysics Data System (ADS)

Suematsu, Yoshinori; Saito, Kosuke; Koyama, Masatsugu; Enokida, Yukiya; Okura, Yukinobu; Nakayasu, Tomoyasu; Sukegawa, Takashi

2017-12-01

We present an innovative optical design for image slicer integral field unit (IFU) and a manufacturing method that overcomes optical limitations of metallic mirrors. Our IFU consists of a micro-mirror slicer of 45 arrayed, highly narrow, flat metallic mirrors and a pseudo-pupil-mirror array of off-axis conic aspheres forming three pseudo slits of re-arranged slicer images. A prototype IFU demonstrates that the final optical quality is sufficiently high for a visible light spectrograph. Each slicer micro-mirror is 1.58 mm long and 30 μm wide with surface roughness ≤1 nm rms, and edge sharpness ≤ 0.1 μm, etc. This IFU is small size and can be implemented in a multi-slit spectrograph without any moving mechanism and fore optics, in which one slit is real and the others are pseudo slits from the IFU. The IFU mirrors were deposited by a space-qualified, protected silver coating for high reflectivity in visible and near IR wavelength regions. These properties are well suitable for space-borne spectrograph such as the future Japanese solar space mission SOLAR-C. We present the optical design, performance of prototype IFU, and space qualification tests of the silver coating.

Fiber IFU unit for the second generation VLT spectrograph KMOS

NASA Astrophysics Data System (ADS)

Tomono, Daigo; Weisz, Harald; Hofmann, Reiner

2003-03-01

KMOS is a cryogenic multi-object near-infrared spectrograph for the VLT. It will be equipped with about 20 deployable integral field units (IFUs) which can be positioned anywhere in the 7.2 arcmin diameter field o the VLT Nasmyth focus by a cryogenic robot. We describe IFUs using micro lens arrays and optical fibers to arrange the two-dimensional fields from the IFUs on the spectrograph entrance slit. Each micro-lens array is mounted in a spider arm which also houses the pre-optics with a cold stop. The spider arms are positioned by a cryogenic robot which is built around the image plane. For the IFUs, two solutions are considered: monolithic mirco-lens arrays with fibers attached to the back where the entrance pupil is imaged, and tapered fibers with integrated lenses which are bundled together to form a lens array. The flexibility of optical fibers relaxes boundary conditions for integration of the instrument components. On the other hand, FRD and geometric characteristics of optical fibers leads to higher AΩ accepted by the spectrograph. Conceptual design of the instrument is presented as well as advantages and disadvantages of the fiber IFUs.

SPDE: Solar Plasma Diagnostic Experiment

NASA Technical Reports Server (NTRS)

Bruner, Marilyn E.

1995-01-01

The physics of the Solar corona is studied through the use of high resolution soft x-ray spectroscopy and high resolution ultraviolet imagery. The investigation includes the development and application of a flight instrument, first flown in May, 1992 on NASA sounding rocket 36.048. A second flight, NASA founding rocket 36.123, took place on 25 April 1994. Both flights were successful in recording new observations relevant to the investigation. The effort in this contract covers completion of the modifications to the existing rocket payload, its reflight, and the preliminary day reduction and analysis. Experience gained from flight 36.048 led us to plan several payload design modifications. These were made to improve the sensitivity balance between the UV and EUV spectrographs, to improve the scattered light rejection in the spectrographs, to protect the visible light rejection filter for the Normal Incidence X-ray Imager instrument (NIXI), and to prepare one new multilayer mirror coating to the NIXI. We also investigated the addition of a brassboard CCD camera to the payload to test it as a possible replacement for the Eastman type 101-07 film used by the SPDE instruments. This camera was included in the experimeter's data package for the Project Initiation Conference for the flight of NASA Mission 36.123, held in January, 1994, but for programmatic reasons was deleted from the final payload configuration. The payload was shipped to the White Sands Missile Range on schedule in early April. The launch and successful recovery took place on 25 April, in coordination with the Yohkoh satellite and a supporting ground-based observing campaign.

Activity status and future plans for the Optical Laboratory of the National Astronomical Research Institute of Thailand

NASA Astrophysics Data System (ADS)

Buisset, Christophe; Poshyachinda, Saran; Soonthornthum, Boonrucksar; Prasit, Apirat; Alagao, Mary Angelie; Choochalerm, Piyamas; Wanajaroen, Weerapot; Lepine, Thierry; Rabbia, Yves; Aukkaravittayapun, Suparerk; Leckngam, Apichat; Thummasorn, Griangsak; Ngernsujja, Surin; Inpan, Anuphong; Kaewsamoet, Pimon; Lhospice, Esther; Meemon, Panomsak; Artsang, Pornapa; Suwansukho, Kajpanya; Sirichote, Wichit; Paenoi, Jitsupa

2018-03-01

The National Astronomical Research Institute of Thailand (NARIT) has developed since June 2014 an optical laboratory that comprises all the activities and facilities related to the research and development of new instruments in the following areas: telescope design, high dynamic and high resolution imaging systems and spectrographs. The facilities include ZEMAX and Solidwork software for design and simulation activities as well as an optical room with all the equipment required to develop optical setup with cutting-edge performance. The current projects include: i) the development of a focal reducer for the 2.3 m Thai National Telescope (TNT), ii) the development of the Evanescent Wave Coronagraph dedicated to the high contrast observations of star close environment and iii) the development of low resolution spectrographs for the Thai National Telescope and for the 0.7 m telescopes of NARIT regional observatories. In each project, our activities start from the instrument optical and mechanical design to the simulation of the performance, the development of the prototype and finally to the final system integration, alignment and tests. Most of the mechanical parts are manufactured by using the facilities of NARIT precision mechanical workshop that includes a 3-axis Computer Numerical Control (CNC) to machine the mechanical structures and a Coordinate Measuring Machine (CMM) to verify the dimensions. In this paper, we give an overview of the optical laboratory activities and of the associated facilities. We also describe the objective of the current projects, present the specifications and the design of the instruments and establish the status of development and we present our future plans.

VizieR Online Data Catalog: VANDELS High-Redshift Galaxy Evolution (McLure+, 2017)

NASA Astrophysics Data System (ADS)

McLure, R.; Pentericci, L.; Vandels Team

2017-11-01

This is the first data release (DR1) of the VANDELS survey, an ESO public spectroscopy survey targeting the high-redshift Universe. The VANDELS survey uses the VIMOS spectrograph on ESO's VLT to obtain ultra-deep, medium resolution, optical spectra of galaxies within the UKIDSS Ultra Deep Survey (UDS) and Chandra Deep Field South (CDFS) survey fields (0.2 sq. degree total area). Using robust photometric redshift pre-selection, VANDELS is targeting ~2100 galaxies in the redshift interval 1.0=3. In addition, VANDELS is targeting a substantial number of passive galaxies in the redshift interval 1.0

Performance characteristics of a suite of volume phase holographic gratings produced for the Subaru prime focus spectrograph

NASA Astrophysics Data System (ADS)

Arns, James A.

2016-08-01

The Subaru Prime Focus Spectrograph[1] (PFS) requires a suite of volume phase holographic (VPH) gratings that parse the observational spectrum into three sub-spectral regions. In addition, the red region has a second, higher resolution arm that includes a VPH grating that will eventually be incorporated into a grism. This paper describes the specifications of the four grating types, gives the theoretical performances of diffraction efficiency for the production designs and presents the measured performances on the gratings produced to date.

VizieR Online Data Catalog: SN2009ip UBVRI, UVOT and JHK light curves (Fraser+, 2013)

NASA Astrophysics Data System (ADS)

Fraser, M.; Inserra, C.; Jerkstrand, A.; Kotak, R.; Pignata, G.; Benetti, S.; Botticella, M.-T.; Bufano, F.; Childress, M.; Mattila, S.; Pastorello, A.; Smartt, S. J.; Turatto, M.; Yuan, F.; Anderson, J. P.; Bayliss, D. D. R.; Bauer, F. E.; Chen, T.-W.; Forster Buron, F.; Gal-Yam, A.; Haislip, J. B.; Knapic, C.; Le Guillou, L.; Marchi, S.; Mazzali, P.; Molinaro, M.; Moore, J. P.; Reichart, D.; Smareglia, R.; Smith, K. W.; Sternberg, A.; Sullivan, M.; Takats, K.; Tucker, B. E.; Valenti, S.; Yaron, O.; Young, D. R.; Zhou, G.

2014-11-01

Optical spectroscopic follow-up of SN 2009ip was chiefly obtained with the New Technology Telescope (NTT) + ESO Faint Object Spectrograph and Camera 2 (EFOSC2), as part of the Public European Southern Observatory (ESO) Spectroscopic Survey of Transient Objects (PESSTO). The PESSTO data were supplemented with data from the Telescopio Nazionale Galileo (TNG) + Device Optimized for the LOw RESolution (DOLORES), and the Australian National University (ANU) 2.3m telescope + Wide Field Spectrograph (WiFeS). (3 data files).

VizieR Online Data Catalog: WIYN open cluster study. LIX. RVs of NGC 6791 (Tofflemire+, 2014)

NASA Astrophysics Data System (ADS)

Tofflemire, B. M.; Gosnell, N. M.; Mathieu, R. D.; Platais, I.

2014-11-01

Our observations utilize the Hydra Multi-Object Spectrograph (MOS) on the WIYN 3.5m telescope. We use 3.1'' diameter fibers along with the bench spectrograph echelle grating, resulting in a spectral resolution of ~20000 (15km/s). See Geller et al. 2008 (cat. J/AJ/135/2264; Paper XXXII) for full details about our observing and data reduction procedures. Variations in our methods from previous WIYN Open Cluster Study (WOCS) radial velocity papers are given in Section 3. (3 data files).

NIRPS: an adaptive-optics assisted radial velocity spectrograph to chase exoplanets around M-stars

NASA Astrophysics Data System (ADS)

Wildi, F.; Blind, N.; Reshetov, V.; Hernandez, O.; Genolet, L.; Conod, U.; Sordet, M.; Segovilla, A.; Rasilla, J. L.; Brousseau, D.; Thibault, S.; Delabre, B.; Bandy, T.; Sarajlic, M.; Cabral, A.; Bovay, S.; Vallée, Ph.; Bouchy, F.; Doyon, R.; Artigau, E.; Pepe, F.; Hagelberg, J.; Melo, C.; Delfosse, X.; Figueira, P.; Santos, N. C.; González Hernández, J. I.; de Medeiros, J. R.; Rebolo, R.; Broeg, Ch.; Benz, W.; Boisse, I.; Malo, L.; Käufl, U.; Saddlemyer, L.

2017-09-01

Since 1st light in 2002, HARPS has been setting the standard in the exo-planet detection by radial velocity (RV) measurements[1]. Based on this experience, our consortium is developing a high accuracy near-infrared RV spectrograph covering YJH bands to detect and characterize low-mass planets in the habitable zone of M dwarfs. It will allow RV measurements at the 1-m/s level and will look for habitable planets around M- type stars by following up the candidates found by the upcoming space missions TESS, CHEOPS and later PLATO. NIRPS and HARPS, working simultaneously on the ESO 3.6m are bound to become a single powerful high-resolution, high-fidelity spectrograph covering from 0.4 to 1.8 micron. NIRPS will complement HARPS in validating earth-like planets found around G and K-type stars whose signal is at the same order of magnitude than the stellar noise. Because at equal resolving power the overall dimensions of a spectrograph vary linearly with the input beam étendue, spectrograph designed for seeing-limited observations are large and expensive. NIRPS will use a high order adaptive optics system to couple the starlight into a fiber corresponding to 0.4" on the sky as efficiently or better than HARPS or ESPRESSO couple the light 0.9" fiber. This allows the spectrograph to be very compact, more thermally stable and less costly. Using a custom tan(θ)=4 dispersion grating in combination with a start-of-the-art Hawaii4RG detector makes NIRPS very efficient with complete coverage of the YJH bands at 110'000 resolution. NIRPS works in a regime that is in-between the usual multi-mode (MM) where 1000's of modes propagates in the fiber and the single mode well suited for perfect optical systems. This regime called few-modes regime is prone to modal noise- Results from a significant R and D effort made to characterize and circumvent the modal noise show that this contribution to the performance budget shall not preclude the RV performance to be achieved.

Resolving z ~2 galaxy using adaptive coadded source plane reconstruction

NASA Astrophysics Data System (ADS)

Sharma, Soniya; Richard, Johan; Kewley, Lisa; Yuan, Tiantian

2018-06-01

Natural magnification provided by gravitational lensing coupled with Integral field spectrographic observations (IFS) and adaptive optics (AO) imaging techniques have become the frontier of spatially resolved studies of high redshift galaxies (z>1). Mass models of gravitational lenses hold the key for understanding the spatially resolved source–plane (unlensed) physical properties of the background lensed galaxies. Lensing mass models very sensitively control the accuracy and precision of source-plane reconstructions of the observed lensed arcs. Effective source-plane resolution defined by image-plane (observed) point spread function (PSF) makes it challenging to recover the unlensed (source-plane) surface brightness distribution.We conduct a detailed study to recover the source-plane physical properties of z=2 lensed galaxy using spatially resolved observations from two different multiple images of the lensed target. To deal with PSF’s from two data sets on different multiple images of the galaxy, we employ a forward (Source to Image) approach to merge these independent observations. Using our novel technique, we are able to present a detailed analysis of the source-plane dynamics at scales much better than previously attainable through traditional image inversion methods. Moreover, our technique is adapted to magnification, thus allowing us to achieve higher resolution in highly magnified regions of the source. We find that this lensed system is highly evident of a minor merger. In my talk, I present this case study of z=2 lensed galaxy and also discuss the applications of our algorithm to study plethora of lensed systems, which will be available through future telescopes like JWST and GMT.

Autonomous spectrographic system to analyse the main elements of fireballs and meteors

NASA Astrophysics Data System (ADS)

Espartero, Francisco Ángel; Martínez, Germán; Frías, Marta; Montes Moya, Francisco Simón; Castro-Tirado, Alberto Javier

2018-01-01

We present a meteor observation system based on imaging CCD cameras, wide-field optics and a diffraction grating. This system is composed of two independent spectrographs with different configurations, which allows us to capture images of fireballs and meteors with several fields of view and sensitivities. The complete set forms a small autonomous observatory, comprised of a sealed box with a sliding roof, weather station and computers for data storing and reduction. Since 2014, several meteors have been studied using this facility, such as the Alcalá la Real fireball recorded on 30 September 2016.

Spectral classification of ASASSN-14az

NASA Astrophysics Data System (ADS)

Benetti, S.; Pastorello, A.; Elias-Rosa, N.; Cappellaro, E.; Tomasella, L.; Ochner, P.; Turatto, M.; Pedani, M.; Harutyunyan, A.

2014-05-01

We report that an optical spectrogram (range 340-800 nm; resolution 1.1 nm), obtained on May 30.19 UT with the TNG (+ DOLORES spectrograph) under the Asiago Transient Classification Program (Tomasella et al. ...

KiwiSpec - an advanced spectrograph for high resolution spectroscopy: optical design and variations

NASA Astrophysics Data System (ADS)

Barnes, Stuart I.; Gibson, Steve; Nield, Kathryn; Cochrane, Dave

2012-09-01

The KiwiSpec R4-100 is an advanced high resolution spectrograph developed by KiwiStar Optics, Industrial Research Ltd, New Zealand. The instrument is based around an R4 echelle grating and a 100mm collimated beam diameter. The optical design employs a highly asymmetric white pupil design, whereby the transfer collimator has a focal length only 1/3 that of the primary collimator. This allows the cross-dispersers (VPH gratings) and camera optics to be small and low cost while also ensuring a very compact instrument. The KiwiSpec instrument will be bre-fed and is designed to be contained in both thermal and/or vacuum enclosures. The instrument concept is highly exible in order to ensure that the same basic design can be used for a wide variety of science cases. Options include the possibility of splitting the wavelength coverage into 2 to 4 separate channels allowing each channel to be highly optimized for maximum eciency. CCDs ranging from smaller than 2K2K to larger than 4K4K can be accommodated. This allows good (3-4 pixel) sampling of resolving powers ranging from below 50,000 to greater than 100,000. Among the specic design options presented here will be a two-channel concept optimized for precision radial velocities, and a four-channel concept developed for the Gemini High- Resolution Optical Spectrograph (GHOST). The design and performance of a single-channel prototype will be presented elsewhere in these proceedings.

Optical Alignment of the Chromospheric Lyman-Alpha SpectroPolarimeter using Sophisticated Methods to Minimize Activities under Vacuum

NASA Technical Reports Server (NTRS)

Giono, G.; Katsukawa, Y.; Ishikawa, R.; Narukage, N.; Kano, R.; Kubo, M.; Ishikawa, S.; Bando, T.; Hara, H.; Suematsu, Y.;

Extreme Ultraviolet Variability Experiment (EVE) on the Solar Dynamics Observatory (SDO): Overview of Science Objectives, Instrument Design, Data Products, and Model Developments

NASA Technical Reports Server (NTRS)

Woods, T. N.; Eparvier, F. G.; Hock, R.; Jones, A. R.; Woodraska, D.; Judge, D.; Didkovsky, L.; Lean, J.; Mariska, J.; Warren, H.;

PRISM Spectrograph Optical Design

NASA Technical Reports Server (NTRS)

Chipman, Russell A.

1995-01-01

The objective of this contract is to explore optical design concepts for the PRISM spectrograph and produce a preliminary optical design. An exciting optical configuration has been developed which will allow both wavelength bands to be imaged onto the same detector array. At present the optical design is only partially complete because PRISM will require a fairly elaborate optical system to meet its specification for throughput (area*solid angle). The most complex part of the design, the spectrograph camera, is complete, providing proof of principle that a feasible design is attainable. This camera requires 3 aspheric mirrors to fit inside the 20x60 cm cross-section package. A complete design with reduced throughput (1/9th) has been prepared. The design documents the optical configuration concept. A suitable dispersing prism material, CdTe, has been identified for the prism spectrograph, after a comparison of many materials.

CARMENES: an overview six months after first light

NASA Astrophysics Data System (ADS)

Quirrenbach, A.; Amado, P. J.; Caballero, J. A.; Mundt, R.; Reiners, A.; Ribas, I.; Seifert, W.; Abril, M.; Aceituno, J.; Alonso-Floriano, F. J.; Anwand-Heerwart, H.; Azzaro, M.; Bauer, F.; Barrado, D.; Becerril, S.; Bejar, V. J. S.; Benitez, D.; Berdinas, Z. M.; Brinkmöller, M.; Cardenas, M. C.; Casal, E.; Claret, A.; Colomé, J.; Cortes-Contreras, M.; Czesla, S.; Doellinger, M.; Dreizler, S.; Feiz, C.; Fernandez, M.; Ferro, I. M.; Fuhrmeister, B.; Galadi, D.; Gallardo, I.; Gálvez-Ortiz, M. C.; Garcia-Piquer, A.; Garrido, R.; Gesa, L.; Gómez Galera, V.; González Hernández, J. I.; Gonzalez Peinado, R.; Grözinger, U.; Guàrdia, J.; Guenther, E. W.; de Guindos, E.; Hagen, H.-J.; Hatzes, A. P.; Hauschildt, P. H.; Helmling, J.; Henning, T.; Hermann, D.; Hernández Arabi, R.; Hernández Castaño, L.; Hernández Hernando, F.; Herrero, E.; Huber, A.; Huber, K. F.; Huke, P.; Jeffers, S. V.; de Juan, E.; Kaminski, A.; Kehr, M.; Kim, M.; Klein, R.; Klüter, J.; Kürster, M.; Lafarga, M.; Lara, L. M.; Lamert, A.; Laun, W.; Launhardt, R.; Lemke, U.; Lenzen, R.; Llamas, M.; Lopez del Fresno, M.; López-Puertas, M.; López-Santiago, J.; Lopez Salas, J. F.; Magan Madinabeitia, H.; Mall, U.; Mandel, H.; Mancini, L.; Marin Molina, J. A.; Maroto Fernández, D.; Martín, E. L.; Martín-Ruiz, S.; Marvin, C.; Mathar, R. J.; Mirabet, E.; Montes, D.; Morales, J. C.; Morales Muñoz, R.; Nagel, E.; Naranjo, V.; Nowak, G.; Palle, E.; Panduro, J.; Passegger, V. M.; Pavlov, A.; Pedraz, S.; Perez, E.; Pérez-Medialdea, D.; Perger, M.; Pluto, M.; Ramón, A.; Rebolo, R.; Redondo, P.; Reffert, S.; Reinhart, S.; Rhode, P.; Rix, H.-W.; Rodler, F.; Rodríguez, E.; Rodríguez López, C.; Rohloff, R. R.; Rosich, A.; Sanchez Carrasco, M. A.; Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schäfer, S.; Schiller, J.; Schmidt, C.; Schmitt, J. H. M. M.; Schöfer, P.; Schweitzer, A.; Shulyak, D.; Solano, E.; Stahl, O.; Storz, C.; Tabernero, H. M.; Tala, M.; Tal-Or, L.; Ulbrich, R.-G.; Veredas, G.; Vico Linares, J. I.; Vilardell, F.; Wagner, K.; Winkler, J.; Zapatero Osorio, M.-R.; Zechmeister, M.; Ammler-von Eiff, M.; Anglada-Escudé, G.; del Burgo, C.; Garcia-Vargas, M. L.; Klutsch, A.; Lizon, J.-L.; Lopez-Morales, M.; Ofir, A.; Pérez-Calpena, A.; Perryman, M. A. C.; Sánchez-Blanco, E.; Strachan, J. B. P.; Stürmer, J.; Suárez, J. C.; Trifonov, T.; Tulloch, S. M.; Xu, W.

2016-08-01

The CARMENES instrument is a pair of high-resolution (R> 80,000) spectrographs covering the wavelength range from 0.52 to 1.71 μm, optimized for precise radial velocity measurements. It was installed and commissioned at the 3.5m telescope of the Calar Alto observatory in Southern Spain in 2015. The first large science program of CARMENES is a survey of 300 M dwarfs, which started on Jan 1, 2016. We present an overview of all subsystems of CARMENES (front end, fiber system, visible-light spectrograph, near-infrared spectrograph, calibration units, etalons, facility control, interlock system, instrument control system, data reduction pipeline, data flow, and archive), and give an overview of the assembly, integration, verification, and commissioning phases of the project. We show initial results and discuss further plans for the scientific use of CARMENES.

Final design of SITELLE: a wide-field imaging Fourier transform spectrometer for the Canada-France-Hawaii Telescope

NASA Astrophysics Data System (ADS)

Grandmont, F.; Drissen, L.; Mandar, Julie; Thibault, S.; Baril, Marc

2012-09-01

We report here on the current status of SITELLE, an imaging Fourier transform spectrometer to be installed on the Canada-France Hawaii Telescope in 2013. SITELLE is an Integral Field Unit (IFU) spectrograph capable of obtaining the visible (350 nm - 900 nm) spectrum of every pixel of a 2k x 2k CCD imaging a field of view of 11 x 11 arcminutes, with 100% spatial coverage and a spectral resolution ranging from R = 1 (deep panchromatic image) to R < 104 (for gas dynamics). SITELLE will cover a field of view 100 to 1000 times larger than traditional IFUs, such as GMOS-IFU on Gemini or the upcoming MUSE on the VLT. SITELLE follows on the legacy of BEAR, an imaging conversion of the CFHT FTS and the direct successor of SpIOMM, a similar instrument attached to the 1.6-m telescope of the Observatoire du Mont-Mégantic in Québec. SITELLE will be used to study the structure and kinematics of HII regions and ejecta around evolved stars in the Milky Way, emission-line stars in clusters, abundances in nearby gas-rich galaxies, and the star formation rate in distant galaxies.

Some inconvenient truths about biosignatures involving two chemical species on Earth-like exoplanets.

PubMed

Rein, Hanno; Fujii, Yuka; Spiegel, David S

2014-05-13

The detection of strong thermochemical disequilibrium in the atmosphere of an extrasolar planet is thought to be a potential biosignature. In this article we present a previously unidentified kind of false positive that can mimic a disequilibrium or any other biosignature that involves two chemical species. We consider a scenario where the exoplanet hosts a moon that has its own atmosphere and neither of the atmospheres is in chemical disequilibrium. Our results show that the integrated spectrum of the planet and the moon closely resembles that of a single object in strong chemical disequilibrium. We derive a firm limit on the maximum spectral resolution that can be obtained for both directly imaged and transiting planets. The spectral resolution of even idealized space-based spectrographs that might be achievable in the next several decades is in general insufficient to break the degeneracy. Both chemical species can only be definitively confirmed in the same object if absorption features of both chemicals can be unambiguously identified and their combined depth exceeds 100%.

Mg, Al, Si, Ca, Ti, Fe, and Ni abundance for a sample of solar analogues

NASA Astrophysics Data System (ADS)

López-Valdivia, Ricardo; Bertone, Emanuele; Chávez, Miguel

2017-05-01

We report on the determination of chemical abundances of 38 solar analogues, including 11 objects previously identified as super-metal-rich stars. We have measured the equivalent widths for 34 lines of 7 different chemical elements (Mg, Al, Si, Ca, Ti, Fe and Ni) in high-resolution (R ˜ 80 000) spectroscopic images, obtained at the Observatorio Astrofísico Guillermo Haro (Sonora, Mexico), with the Cananea High-resolution Spectrograph. We derived chemical abundances using atlas12 model atmospheres and the Fortran code moog. We confirmed the super-metallicity status of six solar analogues. Within our sample, BD+60 600 is the most metal rich star ([Fe/H] = +0.35 dex), while for HD 166991, we obtained the lowest iron abundance ([Fe/H] = -0.53 dex). We also computed the so-called [Ref] index for 25 of our solar analogues, and we found that BD+60 600 ([Ref] = +0.42) and BD+28 3198 ([Ref] = +0.34) are good targets for exoplanet search.

Preparation of the CARMENES Input Catalogue: Mining Public Archives for Stellar Parameters and Spectra of M Dwarfs with Master Thesis Students

NASA Astrophysics Data System (ADS)

Montes, D.; Caballero, J. A.; Alonso-Floriano, F. J.; Cortes Contreras, M.; Gonzalez-Alvarez, E.; Hidalgo, D.; Holgado, G.; Llamas, M.; Martinez-Rodriguez, H.; Sanz-Forcada, J.

2015-01-01

We help compiling the most comprehensive database of M dwarfs ever built, CARMENCITA, the CARMENES Cool dwarf Information and daTa Archive, which will be the CARMENES `input catalogue'. In addition to the science preparation with low- and high-resolution spectrographs and lucky imagers (see the other contributions in this volume), we compile a huge pile of public data on over 2100 M dwarfs, and analyze them, mostly using virtual-observatory tools. Here we describe four specific actions carried out by master and grade students. They mine public archives for additional high-resolution spectroscopy (UVES, FEROS and HARPS), multi-band photometry (FUV-NUV-u-B-g-V-r-R-i-J-H-Ks-W1-W2-W3-W4), X-ray data (ROSAT, XMM-Newton and Chandra), periods, rotational velocities and Hα pseudo-equivalent widths. As described, there are many interdependences between all these data.

A New Approach to Observing Coronal Dynamics: MUSE, the Multi-Slit Solar Explorer

NASA Astrophysics Data System (ADS)

Tarbell, T. D.

2017-12-01

The Multi-Slit Solar Explorer is a Small Explorer mission recently selected for a Phase A study, which could lead to a launch in 2022. It will provide unprecendented observations of the dynamics of the corona and transition region using both conventional and novel spectral imaging techniques. The physical processes that heat the multi-million degree solar corona, accelerate the solar wind and drive solar activity (CMEs and flares) remain poorly known. A breakthrough in these areas can only come from radically innovative instrumentation and state-of-the-art numerical modeling and will lead to better understanding of space weather origins. MUSE's multi-slit coronal spectroscopy will exploit a 100x improvement in spectral raster cadence to fill a crucial gap in our knowledge of Sun-Earth connections; it will reveal temperatures, velocities and non-thermal processes over a wide temperature range to diagnose physical processes that remain invisible to current or planned instruments. MUSE will contain two instruments: an EUV spectrograph (SG) and EUV context imager (CI). Both have similar spatial resolution and leverage extensive heritage from previous high-resolution instruments such as IRIS and the HiC rocket payload. The MUSE investigation will build on the success of IRIS by combining numerical modeling with a uniquely capable observatory: MUSE will obtain EUV spectra and images with the highest resolution in space (1/3 arcsec) and time (1-4 s) ever achieved for the transition region and corona, along 35 slits and a large context FOV simultaneously. The MUSE consortium includes LMSAL, SAO, Stanford, ARC, HAO, GSFC, MSFC, MSU, ITA Oslo and other institutions.

PRAXIS: low thermal emission high efficiency OH suppressed fibre spectrograph

NASA Astrophysics Data System (ADS)

Content, Robert; Bland-Hawthorn, Joss; Ellis, Simon; Gers, Luke; Haynes, Roger; Horton, Anthony; Lawrence, Jon; Leon-Saval, Sergio; Lindley, Emma; Min, Seong-Sik; Shortridge, Keith; Staszak, Nick; Trinh, Christopher; Xavier, Pascal; Zhelem, Ross

2014-07-01

PRAXIS is a second generation instrument that follows on from GNOSIS, which was the first instrument using fibre Bragg gratings for OH suppression to be deployed on a telescope. The Bragg gratings reflect the NIR OH lines while being transparent to the light between the lines. This gives in principle a much higher signal-noise ratio at low resolution spectroscopy but also at higher resolutions by removing the scattered wings of the OH lines. The specifications call for high throughput and very low thermal and detector noise so that PRAXIS will remain sky noise limited even with the low sky background levels remaining after OH suppression. The optical and mechanical designs are presented. The optical train starts with fore-optics that image the telescope focal plane on an IFU which has 19 hexagonal microlenses each feeding a multi-mode fibre. Seven of these fibres are attached to a fibre Bragg grating OH suppression system while the others are reference/acquisition fibres. The light from each of the seven OH suppression fibres is then split by a photonic lantern into many single mode fibres where the Bragg gratings are imprinted. Another lantern recombines the light from the single mode fibres into a multi-mode fibre. A trade-off was made in the design of the IFU between field of view and transmission to maximize the signal-noise ratio for observations of faint, compact objects under typical seeing. GNOSIS used the pre-existing IRIS2 spectrograph while PRAXIS will use a new spectrograph specifically designed for the fibre Bragg grating OH suppression and optimised for 1.47 μm to 1.7 μm (it can also be used in the 1.09 μm to 1.26 μm band by changing the grating and refocussing). This results in a significantly higher transmission due to high efficiency coatings, a VPH grating at low incident angle and optimized for our small bandwidth, and low absorption glasses. The detector noise will also be lower thanks to the use of a current generation HAWAII-2RG detector. Throughout the PRAXIS design, from the fore-optics to the detector enclosure, special care was taken at every step along the optical path to reduce thermal emission or stop it leaking into the system. The spectrograph design itself was particularly challenging in this aspect because practical constraints required that the detector and the spectrograph enclosures be physically separate with air at ambient temperature between them. At present, the instrument uses the GNOSIS fibre Bragg grating OH suppression unit. We intend to soon use a new OH suppression unit based on multicore fibre Bragg gratings which will allow an increased field of view per fibre. Theoretical calculations show that the gain in interline sky background signal-noise ratio over GNOSIS may very well be as high as 9 with the GNOSIS OH suppression unit and 17 with the multicore fibre OH suppression unit.

Performance results from in-flight commissioning of the Juno Ultraviolet Spectrograph (Juno-UVS)

NASA Astrophysics Data System (ADS)

Greathouse, T. K.; Gladstone, G. R.; Davis, M. W.; Slater, D. C.; Versteeg, M. H.; Persson, K. B.; Walther, B. C.; Winters, G. S.; Persyn, S. C.; Eterno, J. S.

2013-09-01

We present a description of the Juno ultraviolet spectrograph (Juno-UVS) and results from its in-flight commissioning performed between December 5th and 13th 2011 and its first periodic maintenance between October 10th and 12th 2012. Juno-UVS is a modest power (9.0 W) ultraviolet spectrograph based on the Alice instruments now in flight aboard the European Space Agency's Rosetta spacecraft, NASA's New Horizons spacecraft, and the LAMP instrument aboard NASA's Lunar Reconnaissance Orbiter. However, unlike the other Alice spectrographs, Juno-UVS sits aboard a spin stabilized spacecraft. The Juno-UVS scan mirror allows for pointing of the slit approximately +/-30° from the spacecraft spin plane. This ability gives Juno-UVS access to half the sky at any given spacecraft orientation. The planned 2 rpm spin rate for the primary mission results in integration times per 0.2° spatial resolution element per spin of only ~17 ms. Thus, for calibration purposes, data were retrieved from many spins and then remapped and co-added to build up exposure times on bright stars to measure the effective area, spatial resolution, scan mirror pointing positions, etc. The primary job of Juno-UVS will be to characterize Jupiter's UV auroral emissions and relate them to in-situ particle measurements. The ability to point the slit will make operations more flexible, allowing Juno-UVS to observe the atmospheric footprints of magnetic field lines through which Juno flies, giving a direct connection between energetic particle measurements on the spacecraft and the far-ultraviolet emissions produced by Jupiter's atmosphere in response to those particles.

Test of multi-object exoplanet search spectral interferometer

NASA Astrophysics Data System (ADS)

Zhang, Kai; Wang, Liang; Jiang, Haijiao; Zhu, Yongtian; Hou, Yonghui; Dai, Songxin; Tang, Jin; Tang, Zhen; Zeng, Yizhong; Chen, Yi; Wang, Lei; Hu, Zhongwen

2014-07-01

Exoplanet detection, a highlight in the current astronomy, will be part of puzzle in astronomical and astrophysical future, which contains dark energy, dark matter, early universe, black hole, galactic evolution and so on. At present, most of the detected Exoplanets are confirmed through methods of radial velocity and transit. Guo shoujing Telescope well known as LAMOST is an advanced multi-object spectral survey telescope equipped with 4000 fibers and 16 low resolution fiber spectrographs. To explore its potential in different astronomical activities, a new radial velocity method named Externally Dispersed Interferometry (EDI) is applied to serve Exoplanet detection through combining a fixed-delay interferometer with the existing spectrograph in medium spectral resolution mode (R=5,000-10,000). This new technology has an impressive feature to enhance radial velocity measuring accuracy of the existing spectrograph through installing a fixed-delay interferometer in front of spectrograph. This way produces an interference spectrum with higher sensitivity to Doppler Effect by interference phase and fixed delay. This relative system named Multi-object Exoplanet Search Spectral Interferometer (MESSI) is composed of a few parts, including a pair of multi-fiber coupling sockets, a remote control iodine subsystem, a multi-object fixed delay interferometer and the existing spectrograph. It covers from 500 to 550 nm and simultaneously observes up to 21 stars. Even if it's an experimental instrument at present, it's still well demonstrated in paper that how MESSI does explore an effective way to build its own system under the existing condition of LAMOST and get its expected performance for multi-object Exoplanet detection, especially instrument stability and its special data reduction. As a result of test at lab, inside temperature of its instrumental chamber is stable in a range of +/-0.5degree Celsius within 12 hours, and the direct instrumental stability without further observation correction is equivalent to be +/-50m/s every 20mins.

Science Discoveries Enabled by Hosting Optical Imagers on Commercial Satellite Constellations

NASA Astrophysics Data System (ADS)

Erlandson, R. E.; Kelly, M. A.; Hibbitts, C.; Kumar, C.; Dyrud, L. P.

2012-12-01

The advent of commercial space activities that utilize large space-based constellations provide a new and cost effective opportunity to acquire multi-point observations. Previously, a custom designed space-based constellation, while technically feasible, would require a substantial monetary investment. However, commercial industry has now been entertaining the concept of hosting payloads on their space-based constellations resulting in low-cost access to space. Examples, include the low Earth orbit Iridium Next constellation as well as communication satellites in geostationary. In some of these constellations data distribution can be provided in real time, a feature relevant to applications in the areas of space weather and disaster monitoring. From the perspective of new scientific discoveries enabled by low cost access to space, the cost and thus value proposition is dramatically changed. For example, a constellation of sixty-six satellites (Iridium Next), hosting a single band or multi-spectral imager can now provide observations of the aurora with a spatial resolution of a few hundred meters at all local times and in both hemispheres simultaneously. Remote sensing of clouds is another example where it is now possible to acquire global imagery at resolutions between 100-1000m. Finally, land use imagery is another example where one can use either imaging or spectrographic imagers to solve a multitude of problems. In this work, we will discuss measurement architectures and the multi-disciplinary scientific discoveries that are enable by large space based constellations.

Spectroscopic Characterisation of CARMENES Target Candidates from FEROS, CAFE and HRS High-Resolution Spectra

NASA Astrophysics Data System (ADS)

Passegger, Vera Maria; Reiners, Ansgar; Jeffers, Sandra V.; Wende, Sebastian; Schöfer, Patrick; Amado, Pedro J.; Caballero, Jose A.; Montes, David; Mundt, Reinhard; Ribas, Ignasi; Quirrenbach, Andreas

2016-07-01

CARMENES (Calar Alto high-Resolution search for M dwarfs with Exoearths with Near-infrared and optical Échelle Spectrographs) started a new planet survey on M-dwarfs in January this year. The new high-resolution spectrographs are operating in the visible and near-infrared at Calar Alto Observatory. They will perform high-accuracy radial-velocity measurements (goal 1 m s-1) of about 300 M-dwarfs with the aim to detect low-mass planets within habitable zones. We characterised the candidate sample for CARMENES and provide fundamental parameters for these stars in order to constrain planetary properties and understand star-planet systems. Using state-of-the-art model atmospheres (PHOENIX-ACES) and χ2-minimization with a downhill-simplex method we determine effective temperature, surface gravity and metallicity [Fe/H] for high-resolution spectra of around 480 stars of spectral types M0.0-6.5V taken with FEROS, CAFE and HRS. We find good agreement between the models and our observed high-resolution spectra. We show the performance of the algorithm, as well as results, parameter and spectral type distributions for the CARMENES candidate sample, which is used to define the CARMENES target sample. We also present first preliminary results obtained from CARMENES spectra.

LWIR hyperspectral change detection for target acquisition and situation awareness in urban areas

NASA Astrophysics Data System (ADS)

Dekker, Rob J.; Schwering, Piet B. W.; Benoist, Koen W.; Pignatti, Stefano; Santini, Federico; Friman, Ola

2013-05-01

This paper studies change detection of LWIR (Long Wave Infrared) hyperspectral imagery. Goal is to improve target acquisition and situation awareness in urban areas with respect to conventional techniques. Hyperspectral and conventional broadband high-spatial-resolution data were collected during the DUCAS trials in Zeebrugge, Belgium, in June 2011. LWIR data were acquired using the ITRES Thermal Airborne Spectrographic Imager TASI-600 that operates in the spectral range of 8.0-11.5 μm (32 band configuration). Broadband data were acquired using two aeroplanemounted FLIR SC7000 MWIR cameras. Acquisition of the images was around noon. To limit the number of false alarms due to atmospheric changes, the time interval between the images is less than 2 hours. Local co-registration adjustment was applied to compensate for misregistration errors in the order of a few pixels. The targets in the data that will be analysed in this paper are different kinds of vehicles. Change detection algorithms that were applied and evaluated are Euclidean distance, Mahalanobis distance, Chronochrome (CC), Covariance Equalisation (CE), and Hyperbolic Anomalous Change Detection (HACD). Based on Receiver Operating Characteristics (ROC) we conclude that LWIR hyperspectral has an advantage over MWIR broadband change detection. The best hyperspectral detector is HACD because it is most robust to noise. MWIR high spatial-resolution broadband results show that it helps to apply a false alarm reduction strategy based on spatial processing.

VizieR Online Data Catalog: Arches cluster: IR phot., extinction and masses (Habibi+, 2013)

NASA Astrophysics Data System (ADS)

Habibi, M.; Stolte, A.; Brandner, W.; Hussmann, B.; Motohara, K.

2013-05-01

We observed the Arches cluster out to its tidal radius using Ks-band and H-band imaging obtained on June 6-10 2008 with NAOS/CONICA at the VLT combined with Subaro/Cisco J-band data to gain a full understanding of the cluster mass distribution. The acquired Ks-band images cover four fields of 27.8*27.8(arcsec) each, provided by the medium resolution camera (S27) with a pixel scale of 0.027(arcsec). During the Ks-band observations, the natural visual seeing varied from 0.61" to 0.98". We achieved typical spatial resolutions of 0.081-0.135(arcsec) on individual frames using this AO setup. Seeing-limited J-band observations, on July 17, 2000, were performed with the CISCO spectrograph and camera which provided a pixel scale of 0.116(arcsec) and a field of view of 2*2(arcmin). An average seeing of 0.49(arcsec) resulted into a Full Width at Half Maximum (FWHM) of the point-spread function (PSF) of 0.39(arcsec) on the combined image. The catalogue includes derived infrared-photometry in J, H and Ks bands as well as derived individual extinction value and stellar masses. We used the NAOS-CONICA observations obtained in March 2002 in the central part of the Arches cluster to cover the whole cluster area. (1 data file).

Status of the Geostationary Spectrograph (GeoSpec) for Earth and Atmospheric Science Applications

NASA Technical Reports Server (NTRS)

Janz, Scott; Hilsenrath, Ernest; Mount, G.; Brune, W.; Heath, D.

2004-01-01

GeoSpec will support future satellite mission concepts in the Atmospheric Sciences and in Land and Ocean Sciences by providing time-resolved measurements of both chemically linked atmospheric trace gas concentrations of important molecules such as O3, NO2, CH2O and SO2 and at the same time coastal and ocean pollution events, tidal effects, and the origin and evolution of aerosol plumes. The instrument design concept in development is a dual spectrograph covering the WMS wavelength region of 310-500 nm and the VIS/NIR wavelength region of 480-900 nm coupled to all reflective telescope and high sensitivity PIN/CMOS area detector. The goal of the project is to demonstrate a system capable of making moderate spatial resolution (750 meters at nadir) hyperspectral measurements (0.6 to 1.2 nm resolution) from a geostationary orbit. This would enable studies of time-varying pollution and coastal change processes with a temporal resolution of 5 minutes on a regional scale to 1 hour on a continental scale. Other spatial resolutions can be supported by varying the focal length of the input telescope. Scientific rationale and instrument design and status will be presented.

Optical design and optical properties of a VUV spectrographic imager for ICON mission

NASA Astrophysics Data System (ADS)

Loicq, Jerome; Kintziger, Christian; Mazzoli, Alexandra; Miller, Tim; Chou, Cathy; Frey, Harald U.; Immel, Thomas J.; Mende, Stephen B.

2016-07-01

In the frame of the ICON (Ionospheric Connection Explorer) mission of NASA led by UC Berkeley, CSL and SSL Berkeley have designed in cooperation a new Far UV spectro-imager. The instrument is based on a Czerny-Turner spectrograph coupled with two back imagers. The whole field of view covers [+/- 12° vertical, +/- 9° horizontal]. The instrument is surmounted by a rotating mirror to adjust the horizontal field of view pointing by +/- 30°. To meet the scientific imaging and spectral requirements the instrument has been optimized. The optimization philosophy and related analysis are presented in the present paper. PSF, distortion map and spectral properties are described. A tolerance study and alignment cases were performed to prove the instrument can be built and aligned. Finally straylight and out of band properties are discussed.

Near-Infrared high resolution spectral survey of comets with GIANO/TNG: The CN red-system at 1.1 μm

NASA Astrophysics Data System (ADS)

Faggi, Sara; Villanueva, Geronimo Luis; Mumma, Michael J.; Tozzi, Gian-Paolo; Brucato, John Robert

2016-10-01

High-resolution spectroscopy in the near-infrared spectral range is a powerful tool to investigate chemical composition and isotopic fractionation.Comets are the best preserved relic of the enfant stages of the solar system. By targeting biologically relevant species in cometary comae and retrieving isotopic (e.g. D/H) and spin isomeric (e.g., ortho- and para- water) ratios, we can study the formation and evolution of solar system matter, address the origin of Earth's oceans and characterize the delivery of organic matter that was essential for the appearance of life on early Earth. We initiated the first high resolution spectral survey of comets ever conducted in the 0.9-2.5 μm range, targeting C/2014 Q2 (Lovejoy), C/2013 US10 (Catalina) and C/2013 X1 (Panstarrs) with GIANO - the near-IR high resolution spectrograph on Telescopio Nazionale Galileo (TNG). In comet Lovejoy, we detected eight ro-vibrational bands of H2O (Faggi et al., 2016, ApJ in press), emission from the red-system of CN, and many other emission lines whose precursors are now being identified. In this talk we will present a new quantum mechanical solar fluorescence model for the CN red system and the retrievals obtained with it from our cometary spectra. These observations open new pathways for cometary science in the near-infrared spectral range (0.9-2.5 μm) and establish the feasibility of astrobiology-related scientific investigations with future high resolution IR spectrographs on 30-m class telescopes, e.g., the HIRES spectrograph on the E-ELT telescope. This work is part of Sara Faggi's Ph.D. thesis project. NASA's Planetary Astronomy Program supported GLV and MJM through funding awarded under proposal 11-PAST11-0045 (M. J. Mumma, PI ).

EMERGENCE OF GRANULAR-SIZED MAGNETIC BUBBLES THROUGH THE SOLAR ATMOSPHERE. III. THE PATH TO THE TRANSITION REGION

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

Ortiz, Ada; Hansteen, Viggo H.; Pontieu, Bart De

2016-07-10

We study, for the first time, the ascent of granular-sized magnetic bubbles from the solar photosphere through the chromosphere into the transition region and above. Such events occurred in a flux emerging region in NOAA 11850 on 2013 September 25. During that time, the first co-observing campaign between the Swedish 1-m Solar Telescope (SST) and the Interface Region Imaging Spectrograph (IRIS) spacecraft was carried out. Simultaneous observations of the chromospheric H α 656.28 nm and Ca ii 854.2 nm lines, plus the photospheric Fe i 630.25 nm line, were made with the CRISP spectropolarimeter at the Spitzer Space Telescope (more » SST ) reaching a spatial resolution of 0.″14. At the same time, IRIS was performing a four-step dense raster of the emerging flux region, taking slit jaw images at 133 (C ii, transition region), 140 (Si iv, transition region), 279.6 (Mg ii k, core, upper chromosphere), and 283.2 nm (Mg ii k, wing, photosphere). Spectroscopy of several lines was performed by the IRIS spectrograph in the far- and near-ultraviolet, of which we have used the Si iv 140.3 and the Mg ii k 279.6 nm lines. Coronal images from the Atmospheric Imaging Assembly of the Solar Dynamics Observatory were used to investigate the possible coronal signatures of the flux emergence events. The photospheric and chromospheric properties of small-scale emerging magnetic bubbles have been described in detail in Ortiz et al. Here we are able to follow such structures up to the transition region. We describe the properties, including temporal delays, of the observed flux emergence in all layers. We believe this may be an important mechanism of transporting energy and magnetic flux from subsurface layers to the transition region and corona.« less

An Infrared Multi-Object Spectrograph (IRMS) with adaptive optics for TMT: the science case

NASA Astrophysics Data System (ADS)

Mobasher, Bahram; Crampton, David; Simard, Luc

2010-07-01

It has been recognized that a Near-Infrared Multi-object Spectrograph (IRMS) as one of the first light instrument on the Thirty Meter Telescope (TMT) would significantly increase the scientific capability of the observatory. The IRMS is planned to be a clone of the MOSFIRE instrument on the Keck telescope. As a result, we use the already available MOSFIRE design and expertise, significantly reducing the total cost and its development time. The IRMS will be a quasi diffraction limited multi-slit spectrograph with moderate resolution (R~4000), fed by Narrow-Field Infrared Adaptive Optics System (NFIRAOS). It images over the 2 arcmin diameter field of view of the NFIRAOS. There are a number of exceedingly important scientific questions, waiting to be addressed by the TMT/IRMS combination. Given its relatively small field of view, it is less affected by the sky background, which is a limiting factor in ground-based observations at near-IR wavelengths. The IRMS is the ideal instrument for studying spectroscopic properties of galaxies at the re-ionization epoch (z > 7), where the Lyman alpha line shifts to the near-ir wavelenghths. It can be used to measure rotation curves of spiral and velocity dispersion of elliptical galaxies at z~2-3 and hence, their spectroscopic mass. It can be used to search for population III stars via their spectroscopic signature and to perform measurement of spectroscopic lines at high redshifts, diagnostic of metallicity. Finally, IRMS allows measurement of the blue shifts in the rest-frame MgII line for high redshift galaxies, used to study the winds, leading to the feedback mechanism, responsible for quenching star formation activity in galaxies.

Interstellar Medium Absorption Profile Spectrograph (IMAPS)

NASA Technical Reports Server (NTRS)

Jenkins, E. B.

1985-01-01

The design and fabrication of an objective-grating echelle spectrograph to fly on sounding rockets and record spectra of stars from approximately 920 to 1120A with a resolving power lambda/delta lambda = 200,000 is discussed. The scientific purpose of the program is to observe, with ten times better velocity resolution than before, the plentiful absorption lines in this spectral region produced by atoms, ions and molecules in the interstellar medium. In addition, an important technical goal is to develop and flight-quality a new ultraviolet, photon-counting image sensor which has a windowless, opaque photocathode and a CCD bombarded directly by the accelerated photoelectrons. Except for some initial difficulties with the performance of CCDs, the development of the payload instrument is relatively straightforward and our overall design goals are satisfied. The first flight occurred in late 1984, but no data were obtained because of an inrush of air degraded the instrument's vacuum and caused the detector's high voltage to arc. A second flight in early 1985 was a complete success and obtained a spectrum of pi Sco. Data from this mission are currently being reduced; quick-look versions of the spectra indicate that excellent results will be obtained. Currently, the payload is being reconfigured to fly on a Spartan mission in 1988.

The Lightcurve Legacy of COS and STIS

NASA Astrophysics Data System (ADS)

Ely, Justin; Bourque, Matthew; Debes, John; Kriss, Gerard; McCullough, Peter R.

2015-08-01

The Cosmic Origin Spectrograph (COS) and Space Telescope Imaging Spectrograph (STIS) onboard the Hubble Space Telescope (HST) have been advancing astronomy with high quality spectroscopic products for years, and in the case of STIS, more than a decade. Though already incredibly productive, there remains an untapped potential of discovery in the data of these instruments. Due to their specific detector designs, both of these instruments can operate in a TIME-TAG mode where each individual photon's arrival time is recorded. Though this ability is typically utilized to provide second-by-second calibrations to the final spectral data, this mode can also be exploited to re-examine the data in the time domain, turning spectra into lightcurves with high temporal and spectral resolution.Nearly all COS and many STIS observations are taken in TIME-TAG mode. For observations that were not specifically designed to carry out time-resolved spectroscopy, the archived data represent an untapped space for discovery. We present here the current status of our on-going efforts to produce a collection of high-level science lightcurves for the entire COS and STIS TIME-TAG archives. Included are details of the time-series reduction software, instrument capabilities in the time-domain, and demonstrations of the current reduced products for a wide range of variable targets such as transits, stellar flares, and white dwarf pulsations.

PyEmir: Data Reduction Pipeline for EMIR, the GTC Near-IR Multi-Object Spectrograph

NASA Astrophysics Data System (ADS)

Pascual, S.; Gallego, J.; Cardiel, N.; Eliche-Moral, M. C.

2010-12-01

EMIR is the near-infrared wide-field camera and multi-slit spectrograph being built for Gran Telescopio Canarias. We present here the work being done on its data processing pipeline. PyEmir is based on Python and it will process automatically data taken in both imaging and spectroscopy mode. PyEmir is begin developed by the UCM Group of Extragalactic Astrophysics and Astronomical Instrumentation.

Solar Imaging UV/EUV Spectrometers Using TVLS Gratings

NASA Technical Reports Server (NTRS)

Thomas, Roger J.

2003-01-01

It is a particular challenge to develop a stigmatic spectrograph for UV, EUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both reimaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-spaced rulings (TULS). A number of solar extreme ultraviolet (EUV) spectrometers have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets Solar Extreme ultraviolet Research Telescope and Spectrograph (SERTS) and Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS). More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. We now combine these ideas into a spectrometer concept that puts varied-line space rulings onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of three new solar spectrometers based on this concept are described: SUMI and RAISE, two sounding rocket payloads, and NEXUS, currently being proposed as a Small-Explorer (SMEX) mission.

The opto-mechanical design of HARMONI: a first light integral field spectrograph for the E-ELT

NASA Astrophysics Data System (ADS)

Thatte, Niranjan A.; Tecza, Mathias; Freeman, David; Gallie, Angus M.; Montgomery, David; Clarke, Fraser; Fragoso-Lopez, Ana Belén.; Fuentes, Javier; Gago, Fernando; Garcia, Adolfo; Gracia, Felix; Kosmalski, Johan; Lynn, James; Sosa, Dario; Arribas, Santiago; Bacon, Roland; Davies, Roger L.; Fusco, Thierry; Lunney, David; Mediavilla, Evencio; Remillieux, Alban; Schnetler, Hermine

2012-09-01

HARMONI is a visible and near-IR integral field spectrograph, providing the E-ELT's spectroscopic capability at first light. It obtains simultaneous spectra of 32000 spaxels, at a range of resolving powers from R~4000 to R~20000, covering the wavelength range from 0.47 to 2.45 μm. The 256 × 128 spaxel field of view has four different plate scales, with the coarsest scale (40 mas) providing a 5″ × 10″ FoV, while the finest scale is a factor of 10 finer (4mas). We describe the opto-mechanical design of HARMONI, prior to the start of preliminary design, including the main subsystems - namely the image de-rotator, the scale-changing optics, the splitting and slicing optics, and the spectrographs. We also present the secondary guiding system, the pupil imaging optics, the field and pupil stops, the natural guide star wavefront sensor, and the calibration unit.

Calibration of EFOSC2 Broadband Linear Imaging Polarimetry

NASA Astrophysics Data System (ADS)

Wiersema, K.; Higgins, A. B.; Covino, S.; Starling, R. L. C.

2018-03-01

The European Southern Observatory Faint Object Spectrograph and Camera v2 is one of the workhorse instruments on ESO's New Technology Telescope, and is one of the most popular instruments at La Silla observatory. It is mounted at a Nasmyth focus, and therefore exhibits strong, wavelength and pointing-direction-dependent instrumental polarisation. In this document, we describe our efforts to calibrate the broadband imaging polarimetry mode, and provide a calibration for broadband B, V, and R filters to a level that satisfies most use cases (i.e. polarimetric calibration uncertainty 0.1%). We make our calibration codes public. This calibration effort can be used to enhance the yield of future polarimetric programmes with the European Southern Observatory Faint Object Spectrograph and Camera v2, by allowing good calibration with a greatly reduced number of standard star observations. Similarly, our calibration model can be combined with archival calibration observations to post-process data taken in past years, to form the European Southern Observatory Faint Object Spectrograph and Camera v2 legacy archive with substantial scientific potential.

Introducing CUBES: the Cassegrain U-band Brazil-ESO spectrograph

NASA Astrophysics Data System (ADS)

Bristow, Paul; Barbuy, Beatriz; Macanhan, Vanessa B.; Castilho, Bruno; Dekker, Hans; Delabre, Bernard; Diaz, Marcos; Gneiding, Clemens; Kerber, Florian; Kuntschner, Harald; La Mura, Giovanni; Reiss, Roland; Vernet, J.

2014-07-01

CUBES is a high-efficiency, medium-resolution (R ≃ 20, 000) spectrograph dedicated to the "ground based UV" (approximately the wavelength range from 300 to 400nm) destined for the Cassegrain focus of one of ESO's VLT unit telescopes in 2018/19. The CUBES project is a joint venture between ESO and Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG) at the Universidade de São Paulo and the Brazilian Laboratório Nacional de Astrofísica (LNA). CUBES will provide access to a wealth of new and relevant information for stellar as well as extra-galactic sources. Principle science cases include the study of heavy elements in metal-poor stars, the direct determination of carbon, nitrogen and oxygen abundances by study of molecular bands in the UV range and the determination of the Beryllium abundance as well as the study of active galactic nuclei and the inter-galactic medium. With a streamlined modern instrument design, high efficiency dispersing elements and UV-sensitive detectors, it will enable a significant gain in sensitivity over existing ground based medium-high resolution spectrographs enabling vastly increased sample sizes accessible to the astronomical community. We present here a brief overview of the project, introducing the science cases that drive the design and discussing the design options and technological challenges.

MIRADAS control system

NASA Astrophysics Data System (ADS)

Rosich Minguell, Josefina; Garzón Lopez, Francisco

2012-09-01

The Mid-resolution InfRAreD Astronomical Spectrograph (MIRADAS, a near-infrared multi-object echelle spectrograph operating at spectral resolution R=20,000 over the 1-2.5μm bandpass) was selected in 2010 by the Gran Telescopio Canarias (GTC) partnership as the next-generation near-infrared spectrograph for the world's largest optical/infrared telescope, and is being developed by an international consortium. The MIRADAS consortium includes the University of Florida, Universidad de Barcelona, Universidad Complutense de Madrid, Instituto de Astrofísica de Canarias, Institut de Física d'Altes Energies, Institut d'Estudis Espacials de Catalunya and Universidad Nacional Autónoma de México. This paper shows an overview of the MIRADAS control software, which follows the standards defined by the telescope to permit the integration of this software on the GTC Control System (GCS). The MIRADAS Control System is based on a distributed architecture according to a component model where every subsystem is selfcontained. The GCS is a distributed environment written in object oriented C++, which runs components in different computers, using CORBA middleware for communications. Each MIRADAS observing mode, including engineering, monitoring and calibration modes, will have its own predefined sequence, which are executed in the GCS Sequencer. These sequences will have the ability of communicating with other telescope subsystems.

A Survey of Near-infrared Diffuse Interstellar Bands

NASA Astrophysics Data System (ADS)

Hamano, Satochi; Kobayashi, Naoto; Kawakita, Hideyo; Ikeda, Yuji; Kondo, Sohei; Sameshima, Hiroaki; Arai, Akira; Matsunaga, Noriyuki; Yasui, Chikako; Mizumoto, Misaki; Fukue, Kei; Izumi, Natsuko; Otsubo, Shogo; Takenada, Keiichi

2018-04-01

We propose a study of interstellar molecules with near-infrared (NIR) high-resolution spectroscopy as a science case for the 3.6-m Devasthal Optical Telescope (DOT). In particular, we present the results obtained on-going survey of diffuse interstellar bands (DIBs) in NIR with the newly developed NIR high-resolution spectrograph WINERED, which offers a high sensitivity in the wavelength range of 0.91-1.36 µm. Using the WINERED spectrograph attached to the 1.3-m Araki telescope in Japan, we obtained high-quality spectra of a number of early-type stars in various environments, such as diffuse interstellar clouds, dark clouds and star-forming regions, to investigate the properties of NIR DIBs and constrain their carriers. As a result, we successfully identified about 50 new NIR DIBs, where only five fairly strong DIBs had been identified previously. Also, some properties of DIBs in the NIR are discussed to constrain the carriers of DIBs.

Development of a near-infrared high-resolution spectrograph (WINERED) for a survey of bulge stars

NASA Astrophysics Data System (ADS)

Tsujimoto, T.; Kobayashi, N.; Yasui, C.; Kondo, S.; Minami, A.; Motohara, K.; Ikeda, Y.; Gouda, N.

2008-07-01

We are developing a new near-infrared high-resolution (R[max] = 100,000) and high-sensitive spectrograph WINERED, which is specifically customized for short NIR bands at 0.9 1.35 μm. WINERED employs an innovative optical system; a portable design and a warm optics without any cold stops. The planned astrometric space mission JASMINE will provide precise positions, distances, and proper motions of the bulge stars. The missing components, the radial velocity and chemical composition will be measured by WINERED. These combined data brought by JASMINE and WINERED will certainly reveal the nature of the Galactic bulge. We plan to complete this instrument for observations of single objects by the end of 2008 and to attach it to various 4 10m telescopes as a PI-type instrument. We hope to upgrade WINERED with a multi-object feed in the future for efficient survey of the JASMINE bulge stars.

VizieR Online Data Catalog: L-σ relation for massive star formation (Chavez+, 2014)

NASA Astrophysics Data System (ADS)

Chavez, R.; Terlevich, R.; Terlevich, E.; Bresolin, F.; Melnick, J.; Plionis, M.; Basilakos, S.

2015-03-01

We observed 128 HIIGx selected from the SDSS DR7 spectroscopic catalogue (Abazajian et al., 2009ApJS..182..543A) for having the strongest emission lines relative to the continuum (i.e. largest equivalent widths) and in the redshift range 0.01

Calibration and operation of the Faint Object Spectrograph

NASA Technical Reports Server (NTRS)

Harms, R.; Beaver, E.; Burbidge, E.; Hier, R.; Allen, R.; Angel, R.; Bartko, F.; Bohlin, R.; Ford, H.; Davidson, A.

1984-01-01

The design and basic performance characteristics of the Faint Object Spectrograph (FOS), one of five instruments built for use on the Space Telescope observatory, is summarized briefly. The results of the recently completed instrument-level calibration are presented with special emphasis on issues affecting plans for FOS astronomical observations. Examples include such fundamental characteristics as: limiting magnitudes (system sensitivity and noise figures), spectral coverage and resolution, scattered light properties, and instrumental polarization and modulation efficiencies. Also gated toward intended users, a rather detailed description of FOS operating modes is given. The discussion begins with the difficulties anticipated during target acquisition and their hoped-for resolution. Both the 'normal' spectroscopic operating modes of the FOS and its 'exotic' features (e.g. spectropolarimetric, time-tagged, and time-resolved modes) are presented. The paper concludes with an overview of the activities to assure proper alignment and operation of the FOS within the entire Space Telescope system (orbital and ground-based).

Cosmic Evolution Through UV Spectroscopy (CETUS): A NASA Probe-Class Mission Concept

NASA Astrophysics Data System (ADS)

Heap, Sara R.; CETUS Team

2017-01-01

CETUS is a probe-class mission concept proposed for study to NASA in November 2016. Its overarching objective is to provide access to the ultraviolet (~100-400 nm) after Hubble has died. CETUS will be a major player in the emerging global network of powerful, new telescopes such as E-ROSITA, DESI, Subaru/PFS, GMT, LSST, WFIRST, JWST, and SKA. The CETUS mission concept provisionally features a 1.5-m telescope with a suite of instruments including a near-UV multi-object spectrograph (200-400 nm) complementing Subaru/PFS observations, wide-field far-UV and near-UV cameras, and far-UV and near-UV spectrographs that can be operated in either high-resolution or low-resolution mode. We have derived the scope and specific science requirements for CETUS for understanding the evolutionary history of galaxies, stars, and dust, but other applications are possible.

Reflective correctors for the Hubble Space Telescope axial instruments

NASA Technical Reports Server (NTRS)

Bottema, Murk

1993-01-01

Reflective correctors to compensate the spherical aberration in the Hubble Space Telescope are placed in front of three of the axial scientific instruments (a camera and two spectrographs) during the first scheduled refurbishment mission. The five correctors required are deployed from a new module that replaces the fourth axial instrument. Each corrector consists of a field mirror and an aspherical, aberration-correcting reimaging mirror. In the camera the angular resolution capability is restored, be it in reduced fields, and in the spectrographs the potential for observations in crowded areas is regained along with effective light collection at the slits.

High-resolution Observations of Hα Spectra with a Subtractive Double Pass

NASA Astrophysics Data System (ADS)

Beck, C.; Rezaei, R.; Choudhary, D. P.; Gosain, S.; Tritschler, A.; Louis, R. E.

2018-02-01

High-resolution imaging spectroscopy in solar physics has relied on Fabry-Pérot interferometers (FPIs) in recent years. FPI systems, however, become technically challenging and expensive for telescopes larger than the 1 m class. A conventional slit spectrograph with a diffraction-limited performance over a large field of view (FOV) can be built at much lower cost and effort. It can be converted into an imaging spectro(polari)meter using the concept of a subtractive double pass (SDP). We demonstrate that an SDP system can reach a similar performance as FPI-based systems with a high spatial and moderate spectral resolution across a FOV of 100^'' ×100^' ' with a spectral coverage of 1 nm. We use Hα spectra taken with an SDP system at the Dunn Solar Telescope and complementary full-disc data to infer the properties of small-scale superpenumbral filaments. We find that the majority of all filaments end in patches of opposite-polarity fields. The internal fine-structure in the line-core intensity of Hα at spatial scales of about 0.5'' exceeds that in other parameters such as the line width, indicating small-scale opacity effects in a larger-scale structure with common properties. We conclude that SDP systems in combination with (multi-conjugate) adaptive optics are a valid alternative to FPI systems when high spatial resolution and a large FOV are required. They can also reach a cadence that is comparable to that of FPI systems, while providing a much larger spectral range and a simultaneous multi-line capability.

Mapping alteration using imagery from the Tiangong-1 hyperspectral spaceborne system: Example for the Jintanzi gold province, China

NASA Astrophysics Data System (ADS)

Liu, Lei; Feng, Jilu; Rivard, Benoit; Xu, Xinliang; Zhou, Jun; Han, Ling; Yang, Junlu; Ren, Guangli

2018-02-01

The Tiangong-1 Hyperspectral Imager (HSI) is a relatively new spaceborne hyperspectral remote sensing system that was launched by the Chinese government on September 29th 2011. The system has 64 shortwave infrared (SWIR) spectral bands (1000-2500 nm) and imagery is at a spatial resolution of 20 m. This study represents an evaluation of Tiangong-1 data for the production of alteration mineral maps. Alteration mineral maps resulting from the analysis of Tiangong-1 HSI data and airborne SASI (Shortwave infrared Airborne Spectrographic Imager) data are compared for the Jintanzi area, Beishan, Gansu province, northwest China where gold bearing veins are documented. The results illustrate the detection of muscovite, kaolinite, chlorite, epidote, calcite and dolomite from Tiangong-1 HSI data and most anomalies seen in the airborne SASI data are captured. The Tiangong-1 data appears to be well suited for the detection of surface mineralogy in support of regional mapping and exploration. The data complements that which will be offered by the Chinese GF-5 Hyperspectral Imager and the German EnMAP system, both scheduled for launch in 2018.

Observing Exoplanets with High-dispersion Coronagraphy. II. Demonstration of an Active Single-mode Fiber Injection Unit

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

Mawet, D.; Ruane, G.; Xuan, W.

2017-04-01

High-dispersion coronagraphy (HDC) optimally combines high-contrast imaging techniques such as adaptive optics/wavefront control plus coronagraphy to high spectral resolution spectroscopy. HDC is a critical pathway toward fully characterizing exoplanet atmospheres across a broad range of masses from giant gaseous planets down to Earth-like planets. In addition to determining the molecular composition of exoplanet atmospheres, HDC also enables Doppler mapping of atmosphere inhomogeneities (temperature, clouds, wind), as well as precise measurements of exoplanet rotational velocities. Here, we demonstrate an innovative concept for injecting the directly imaged planet light into a single-mode fiber, linking a high-contrast adaptively corrected coronagraph to a high-resolutionmore » spectrograph (diffraction-limited or not). Our laboratory demonstration includes three key milestones: close-to-theoretical injection efficiency, accurate pointing and tracking, and on-fiber coherent modulation and speckle nulling of spurious starlight signal coupling into the fiber. Using the extreme modal selectivity of single-mode fibers, we also demonstrated speckle suppression gains that outperform conventional image-based speckle nulling by at least two orders of magnitude.« less

ELLERMAN BOMBS AT HIGH RESOLUTION. III. SIMULTANEOUS OBSERVATIONS WITH IRIS AND SST

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

Vissers, G. J. M.; Voort, L. H. M. Rouppe van der; Rutten, R. J.

Ellerman bombs (EBs) are transient brightenings of the extended wings of the solar Balmer lines in emerging active regions. We describe their properties in the ultraviolet lines sampled by the Interface Region Imaging Spectrograph (IRIS), using simultaneous imaging spectroscopy in Hα with the Swedish 1-m Solar Telescope (SST) and ultraviolet images from the Solar Dynamics Observatory for Ellerman bomb detection and identification. We select multiple co-observed EBs for detailed analysis. The IRIS spectra strengthen the view that EBs mark reconnection between bipolar kilogauss fluxtubes with the reconnection and the resulting bi-directional jet located within the solar photosphere and shielded bymore » overlying chromospheric fibrils in the cores of strong lines. The spectra suggest that the reconnecting photospheric gas underneath is heated sufficiently to momentarily reach stages of ionization normally assigned to the transition region and the corona. We also analyze similar outburst phenomena that we classify as small flaring arch filaments and ascribe to reconnection at a higher location. They have different morphologies and produce hot arches in million-Kelvin diagnostics.« less

A laser frequency comb that enables radial velocity measurements with a precision of 1 cm s(-1).

PubMed

Li, Chih-Hao; Benedick, Andrew J; Fendel, Peter; Glenday, Alexander G; Kärtner, Franz X; Phillips, David F; Sasselov, Dimitar; Szentgyorgyi, Andrew; Walsworth, Ronald L

2008-04-03

Searches for extrasolar planets using the periodic Doppler shift of stellar spectral lines have recently achieved a precision of 60 cm s(-1) (ref. 1), which is sufficient to find a 5-Earth-mass planet in a Mercury-like orbit around a Sun-like star. To find a 1-Earth-mass planet in an Earth-like orbit, a precision of approximately 5 cm s(-1) is necessary. The combination of a laser frequency comb with a Fabry-Pérot filtering cavity has been suggested as a promising approach to achieve such Doppler shift resolution via improved spectrograph wavelength calibration, with recent encouraging results. Here we report the fabrication of such a filtered laser comb with up to 40-GHz (approximately 1-A) line spacing, generated from a 1-GHz repetition-rate source, without compromising long-term stability, reproducibility or spectral resolution. This wide-line-spacing comb, or 'astro-comb', is well matched to the resolving power of high-resolution astrophysical spectrographs. The astro-comb should allow a precision as high as 1 cm s(-1) in astronomical radial velocity measurements.

Studying focal ratio degradation of optical fibers for Subaru's Prime Focus Spectrograph

NASA Astrophysics Data System (ADS)

dos Santos, Jesulino Bispo; de Oliveira, Antonio Cesar; Gunn, James; de Oliveira, Ligia Souza; Vital de Arruda, Marcio; Castilho, Bruno; Gneiding, Clemens Darvin; Ribeiro, Flavio Felipe; Murray, Graham; Reiley, Daniel J.; Sodré Junior, Laerte; de Oliveira, Claudia Mendes

2014-07-01

Focal Ration Degradation (FRD) is a change in light's angular distribution caused by fiber optics. FRD is important to fiber-fed, spectroscopic astronomical systems because it can cause loss of signal, degradation in spectral resolution, or increased complexity in spectrograph design. Laboratório Nacional de Astrofísica (LNA) has developed a system that can accurately and precisely measures FRD, using an absolute method that can also measure fiber throughput. This paper describes the metrology system and shows measurements of Polymicro's fiber FBP129168190, FBP127165190 and Fujikura fiber 128170190. Although the FRD of the two fibers are low and similar to one another, it is very important to know the exact characteristics of these fibers since both will be used in the construction of FOCCoS (Fiber Optical Cable and Connectors System) for PFS (Prime Focus Spectrograph) to be installed at the Subaru telescope.

Characterization and optimization for detector systems of IGRINS

NASA Astrophysics Data System (ADS)

Jeong, Ueejeong; Chun, Moo-Young; Oh, Jae Sok; Park, Chan; Yuk, In-Soo; Oh, Heeyoung; Kim, Kang-Min; Ko, Kyeong Yeon; Pavel, Michael D.; Yu, Young Sam; Jaffe, Daniel T.

2014-07-01

IGRINS (Immersion GRating INfrared Spectrometer) is a high resolution wide-band infrared spectrograph developed by the Korea Astronomy and Space Science Institute (KASI) and the University of Texas at Austin (UT). This spectrograph has H-band and K-band science cameras and a slit viewing camera, all three of which use Teledyne's λc~2.5μm 2k×2k HgCdTe HAWAII-2RG CMOS detectors. The two spectrograph cameras employ science grade detectors, while the slit viewing camera includes an engineering grade detector. Teledyne's cryogenic SIDECAR ASIC boards and JADE2 USB interface cards were installed to control those detectors. We performed experiments to characterize and optimize the detector systems in the IGRINS cryostat. We present measurements and optimization of noise, dark current, and referencelevel stability obtained under dark conditions. We also discuss well depth, linearity and conversion gain measurements obtained using an external light source.

Electrostatic Spectrograph with a Wide Range of Simultaneously Recorded Energies Composed of Two Coaxial Electrodes with Closed End Faces and a Discrete Combined External Electrode

NASA Astrophysics Data System (ADS)

Fishkova, T. Ya.

2018-01-01

An optimal set of geometric and electrical parameters of a high-aperture electrostatic charged-particle spectrograph with a range of simultaneously recorded energies of E/ E min = 1-50 has been found by computer simulation, which is especially important for the energy analysis of charged particles during fast processes in various materials. The spectrograph consists of two coaxial electrodes with end faces closed by flat electrodes. The external electrode with a conical-cylindrical form is cut into parts with potentials that increase linearly, except for the last cylindrical part, which is electrically connected to the rear end electrode. The internal cylindrical electrode and the front end electrode are grounded. In the entire energy range, the system is sharply focused on the internal cylindrical electrode, which provides an energy resolution of no worse than 3 × 10-3.

Spectrum from Faint Galaxy IRAS F00183-7111

NASA Technical Reports Server (NTRS)

2003-01-01

NASA's Spitzer Space Telescope has detected the building blocks of life in the distant universe, albeit in a violent milieu. Training its powerful infrared eye on a faint object located at a distance of 3.2 billion light-years, Spitzer has observed the presence of water and organic molecules in the galaxy IRAS F00183-7111. With an active galactic nucleus, this is one of the most luminous galaxies in the universe, rivaling the energy output of a quasar. Because it is heavily obscured by dust (see visible-light image in the inset), most of its luminosity is radiated at infrared wavelengths.

The infrared spectrograph instrument onboard Spitzer breaks light into its constituent colors, much as a prism does for visible light. The image shows a low-resolution spectrum of the galaxy obtained by the spectrograph at wavelengths between 4 and 20 microns. Spectra are graphical representations of a celestial object's unique blend of light. Characteristic patterns, or fingerprints, within the spectra allow astronomers to identify the object's chemical composition and to determine such physical properties as temperature and density.

The broad depression in the center of the spectrum denotes the presence of silicates (chemically similar to beach sand) in the galaxy. An emission peak within the bottom of the trough is the chemical signature for molecular hydrogen. The hydrocarbons (orange) are organic molecules comprised of carbon and hydrogen, two of the most common elements on Earth. Since it has taken more than three billion years for the light from the galaxy to reach Earth, it is intriguing to note the presence of organics in a distant galaxy at a time when life is thought to have started forming on our home planet.

Additional features in the spectrum reveal the presence of water ice (blue), carbon dioxide ice (green) and carbon monoxide (purple) in both gas and solid forms. The magenta peak corresponds to singly ionized neon gas, a spectral line often used by astronomers as a diagnostic of star formation rates in distant galaxies.

The Spitzer spectrum is the result of only 14 minutes of integration time, highlighting the power of the infrared spectrograph to unlock the secrets of distant galaxies.

The Magellan Project

NASA Astrophysics Data System (ADS)

Shectman, Stephen A.

1995-05-01

The Magellan project is a collaboration between the Carnegie Institution of Washington and the University of Arizona to build and operate a 6.5-meter telescope at the Las Campanas Observatory in Chile. Negotiations which are presently underway with additional partners are likely to result in the construction of a second identical telescope as part of the same facility. The concrete work for the first telescope has been completed. The steel structure for the fixed part of the dome and for the aluminizing building has been shipped to the site. The structure for the rotating part of the dome should arrive at the site by the end of 1995. The telescope mount is being constructed by L&F Industries of Huntington Park, CA. Most of the structure has been fabricated and machining of the parts is underway. Shop assembly of the mount is scheduled to be completed by the end of 1995, and the mount should arrive at the site by mid-1996. The borosilicate honeycomb mirror blank for the first telescope was cast at the Steward Observatory Mirror Lab in February, 1994. The refractory material is presently being cleaned out of the honeycomb cores, and figuring should begin in 1996. The schedule calls for the mirror to be installed in the telescope by mid-1997. The optical design of the telescope features an f/11 Gregorian secondary for which the field curvature is matched to the collimator optics of a wide-field imaging spectrograph. A two-element field corrector incorporates an atmospheric dispersion compensator with no additional glass-air surfaces. The matching field curvatures permit the collimator to cover a very wide field (30 arc-min) with high image quality (0.1 arc-sec rms). Cameras and detectors which make use of such a wide field are challenging but at least conceivable from a technical point of view. A compact echelle spectrograph has also been designed to work in the resolution range 30-50,000. Spectral coverage will be complete between 3500A and 8500A. The spectrograph has been designed for high throughput and the CCD readouts will be optimized in a novel way to minimize the effect of amplifier noise for observations of faint objects.

CARMENES science preparation: characterisation of M dwarfs with low-resolution spectroscopy and search for low-mass wide companions to young stars

NASA Astrophysics Data System (ADS)

Alonso-Floriano, F. J.

2015-11-01

This thesis is focused on the study of low-mass objects that can be targets of exoplanet searches with near-infrared spectrographs in general and CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs; see Quirrenbach et al. 2014) in particular. The CARMENES consortium comprises 11 institutions from Germany and Spain that are building a high-resolution spectrograph (R=82,000) with two channels, visible (0.55 - 1.05 um) and infrared (0.95 - 1.7 um), for the 3.5 m Calar Alto telescope. It will observe a sample of 300 M dwarfs in 600 nights of guaranteed time during at least three years, starting in January 2016. The final sample will be chosen from the 2200 M dwarfs included in the CARMENCITA input catalogue. For these stars, we have obtained and collected a large amount of data: spectral types, radial and rotational velocities, photometry in several bands, etc. Part of the e effort of the science preparation necessary for the final selection of targets for CARMENES and other near-infrared spectrographs has been collected in two publications, which are presented in this PhD thesis. In the first publication (Alonso-Floriano et al., 2015A&A...577A.128A), we obtained low-resolution spectra for 753 stars using the CAFOS spectrograph at the 2.2 m Calar Alto telescope. The main goal was to derive accurate spectral types, which are fundamental parameters for the sample selection. We used a grid of 49 standard stars, from spectral types K3V to M8V, together with a double least-square minimisation technique and 31 spectral indices previously defined by other authors. In addition, we quantified the surface gravity, metallicity and chromospheric activity of the sample, in order to detect low-gravity stars (giants and very young), metal-poor and very metal-poor stars (subdwarfs), and very active stars. In the second publication (Alonso-Floriano et al., 2015A&A...583A..85A), we searched for common proper motion companions, especially of low mass, to members of the near young beta Pictoris moving group. First, we compiled a list of 185 members and candidate members to beta Pictoris from 35 representatives studies on this moving group. Next, we used the Aladin and STILTS virtual observatory tools, as well as the PPMXL proper motion and Washington double stars catalogues. The objects that showed similar proper motions to those stars of the sample were targets of an astro-photometric follow-up. The 36 common proper motion companion eventually obtained were subjects of a study of binding energies to determine their physical ligation.

Development of compact integral field unit for spaceborne solar spectro-polarimeter

NASA Astrophysics Data System (ADS)

Suematsu, Y.; Koyama, M.; Sukegawa, T.; Enokida, Y.; Saito, K.; Okura, Y.; Nakayasu, T.; Ozaki, S.; Tsuneta, S.

2017-11-01

A 1.5-m class aperture Solar Ultra-violet Visible and IR telescope (SUVIT) and its instruments for the Japanese next space solar mission SOLAR-C [1] are under study to obtain critical physical parameters in the lower solar atmosphere. For the precise magnetic field measurements covering field-of-view of 3 arcmin x3 acmin, a full stokes polarimetry at three magnetic sensitive lines in wavelength range of 525 nm to 1083 nm with a four-slit spectrograph of two dinesional image scanning mechanism is proposed: one is a true slit and the other three are pseudo-slits from integral field unit (IFU). To suit this configuration, besides a fiber bundle IFU, a compact mirror slicer IFU is designed and being developed. Integral field spectroscopy (IFS), which is realized with IFU, is a two dimensional spectroscopy, providing spectra simultaneously for each spatial direction of an extended two-dimensional field. The scientific advantages of the IFS for studies of localized and transient solar surface phenomena are obvious. There are in general three methods [2][3] to realize the IFS depending on image slicing devices such as a micro-lenslet array, an optical fiber bundle and a narrow rectangular image slicer array. So far, there exist many applications of the IFS for ground-based astronomical observations [4]. Regarding solar instrumentations, the IFS of micro-lenslet array was done by Suematsu et al. [5], the IFS of densely packed rectangular fiber bundle with thin clads was realized [6] and being developed for 4-m aperture solar telescope DKIST by Lin [7] and being considered for space solar telescope SOLAR-C by Katsukawa et al. [8], and the IFS with mirror slicer array was presented by Ren et al. [9] and under study for up-coming large-aperture solar telescope in Europe by Calcines et al. [10] From the view point of a high efficiency spectroscopy, a wide wavelength coverage, a precision spectropolarimetry and space application, the image slicer consisting of all reflective optics is the best option among the three. However, the image slicers are presently limited either by their risk in the case of classical glass polishing techniques (see Vivès et al. [11] for recent development) or by their optical performances when constituted by metallic mirrors. For space instruments, small sized units are much advantageous and demands that width of each slicer mirror is as narrow as an optimal slit width (< 100 micron) of spectrograph which is usually hard to manufacture with glass polishing techniques. On the other hand, Canon is developing a novel technique for such as high performance gratings which can be applicable for manufacturing high optical performance metallic mirrors of small dimensions. For the space-borne spectrograph of SUVIT to be aboard SOLAR-C, we designed the IFS made of a micro image slicer of 45 arrayed 30-micron-thick metal mirrors and a pseudo-pupil metal mirror array re-formatting three pseudo-slits; the design is feasible for optical configuration sharing a spectrograph with a conventional real slit. According to the optical deign, Canon manufactured a prototype IFU for evaluation, demonstrating high performances of micro image slicer and pupil mirrors; enough small micro roughness for visible light spectrographs, sharp edges for efficient image slices, surface figure for high image quality, etc. In the following, we describe the optical design of IFU feasible for space-borne spectrograph, manufacturing method to attain high optical performance of metal mirrors developed by Canon, and resulted performance of prototype IFU in detail.

KiwiSpec - an advanced spectrograph for high resolution spectroscopy: prototype design and performance

NASA Astrophysics Data System (ADS)

Gibson, Steve; Barnes, Stuart I.; Hearnshaw, John; Nield, Kathryn; Cochrane, Dave; Grobler, Deon

2012-09-01

A new advanced high resolution spectrograph has been developed by Kiwistar Optics of Industrial Research Ltd., New Zealand. The instrument, KiwiSpec R4-100, is bench-mounted, bre-fed, compact (0.75m by 1.5m footprint), and is well-suited for small to medium-sized telescopes. The instrument makes use of several advanced concepts in high resolution spectrograph design. The basic design follows the classical white pupil concept in an asymmetric implementation and employs an R4 echelle grating illuminated by a 100mm diameter collimated beam for primary dispersion. A volume phase holographic grating (VPH) based grism is used for cross-dispersion. The design also allows for up to four camera and detector channels to allow for extended wavelength coverage at high eciency. A single channel prototype of the instrument has been built and successfully tested with a 1m telescope. Targets included various spectrophotometric standard stars and several radial velocity standard stars to measure the instrument's light throughput and radial velocity capabilities. The prototype uses a 725 lines/mm VPH grism, an off-the-shelf camera objective, and a 2k×2k CCD. As such, it covers the wavelength range from 420nm to 660nm and has a resolving power of R ≍ 40,000. Spectrophotometric and precision radial velocity results from the on-sky testing period will be reported, as well as results of laboratory-based measurements. The optical design of KiwiSpec, and the various multi-channel design options, will be presented elsewhere in these proceedings.

New Thermal Infrared Hyperspectral Imagers

DTIC Science & Technology

2009-10-01

involve imaging systems based on both MCT and microbolometer detector . All the systems base on push-broom imaging spectrograph with transmission grating...application requirements. The studies involve imaging systems based on both MCT and microbolometer detector . All the systems base on push-broom...remote sensing imager utilizes MCT detector combined with BMC-technique (background monitoring on-chip), background suppression and temperature

Classification of ASASSN-18ix as a dwarf nova

NASA Astrophysics Data System (ADS)

Aydi, E.; Buckley, D. A. H.; Mohamed, S.; Whitelock, P. A.; Chomiuk, L.; Strader, J.; Stanek, K. Z.

2018-05-01

We report on SALT high-resolution spectroscopy of ASASSN-18ix which was reported as a possible Galactic nova by K. Z. Stanek et al. (ATel #11561). We obtained a 2000 s spectrum of this object under the SALT Large Science Program on transients on 2018 April 24.99 (HJD 2458233.50), using the High Resolution Spectrograph (HRS; Crause et al. 2014, Proc.

Prototype Imaging Spectrograph for Coronagraphic Exoplanet Studies (PISCES) for WFIRST/AFTA

NASA Technical Reports Server (NTRS)

Gong, Qian; McElwain, Michael; Greeley, Bradford; Grammer, Bryan; Marx, Catherine; Memarsadeghi, Nargess; Hilton, George; Perrin, Marshall; Sayson, Llop; Domingo, Jorge;

Origins, Structure, and Evolution of Magnetic Activity in the Cool Half of the H--R Diagram: an HST STIS Survey

NASA Astrophysics Data System (ADS)

Ayres, T. R.; Brown, A.; Drake, S. A.; Dupree, A. K.; Guedel, M.; Guinan, E.; Harper, G. M.; Jordan, C.; Linsky, J. L.; Reimers, D.; Schmitt, J. H. M. M.; Simon, T.

1999-12-01

In HST's cycle 8, we are carrying out a major ultraviolet spectral survey of late-type stars using the powerful capabilities of the Space Telescope Imaging Spectrograph (STIS). The origin of the hot UV emissions of otherwise cool stars is a fundamental puzzle in astrophysics. Magnetic phenomena---at the heart of chromospheric and coronal activity, and perhaps wind driving as well---play a central role in many cosmic settings. Our objective is to obtain high-quality ultraviolet spectra of a diverse collection of F--K stars, of all luminosity classes. Such a major project was unthinkable before STIS, but now is practical given the high resolution, broad spectral coverage, and sensitivity of the second generation spectrograph. Here, we discuss our choice of the thirteen targets; the observing strategy (which captures the entire UV spectrum between 1150--3000 Angstroms at resolutions λ /δ λ 30--100*E3 with good S/N); and preliminary results for the several targets observed to date (ζ Dor, F7 V, 1 May 1999, 2 CVZ orbits; V711 Tau, K1 IV+G5 IV, 15 September 1999, 5 orbits; β Cam, G0 I, 19 September 1999, 4 CVZ orbits). The observation of V711 Tau (HR 1099) was carried out during a long transmission grating pointing by the Chandra X-ray Observatory, in support of its ``Emission Line Project.'' This work was supported by grant GO-08280.01-97A from STScI. Observations were from the NASA/ESA HST, collected at the STScI, operated by AURA, under contract NAS5-26555.

VizieR Online Data Catalog: Spectroscopy of main-belt Ch/Cgh-type asteroids (Vernazza+, 2016)

NASA Astrophysics Data System (ADS)

Vernazza, P.; Marsset, M.; Beck, P.; Binzel, R. P.; Birlan, M.; Cloutis, E. A.; DeMeo, F. E.; Dumas, C.; Hiroi, T.

2016-09-01

We conducted an extensive spectroscopic survey in the near-infrared range of 70 main-belt Ch/Cgh-type asteroids and 4 Ch/Cgh-type families and combined these measurements with available visible wavelength spectra. New data presented here are near-infrared asteroid spectral measurements for Ch- and Cgh-type asteroids from 0.7-2.5μm obtained using SpeX, the low- to medium-resolution near-IR spectrograph and imager on the 3m NASA InfraRed Telescope Facility (IRTF) located on Mauna Kea, HI. Observing runs were conducted remotely primarily from the Observatory of Paris-Meudon, France between 2010 April and 2012 January. The spectrograph SpeX, combined with a 0.8*15arcsec slit, was used in the low-resolution prism mode for acquisition of the spectra in the 0.7-2.5μm wavelength range. In order to monitor the high luminosity and variability of the sky in the near-IR, the telescope was moved along the slit during the acquisition of the data so as to obtain a sequence of spectra located at two different positions (A and B) on the array. In addition, we complemented our data set with additional near-infrared spectra retrieved from the Small Main-Belt Asteroid Spectroscopic Survey (SMASS) database (http://smass.mit.edu/). Combining these near-infrared measurements with available visible wavelength spectra (Bus, 1999PhDT........50B; Lazzaro et al., 2004Icar..172..179L) allows for the first time an extensive visible and near-infrared (VNIR) spectral database of main-belt Ch and Cgh types with D>45km (78% or 49/63 of all Ch and Cgh types listed in SMASS; see Table1). (1 data file).

Performance of The Far Ultraviolet Spectroscopic Explorer Mirror Assemblies

NASA Technical Reports Server (NTRS)

Ohi, Raymond G.; Barkhouser, Robert H.; Conard, Steven J.; Friedman, Scott D.; Hampton, Jeffery; Moos, H. Warren; Nikulla, Paul; Oliveira, Cristina M.; Saha, Timo T.; Obenschain, Arthur (Technical Monitor)

2000-01-01

The Far Ultraviolet Spectroscopic Explorer is a NASA astrophysics satellite which produces high-resolution spectra in the far-ultraviolet (90.5-118.7 nm bandpass) using a high effective area and low background detectors. The observatory was launched on its three-year mission from Cape Canaveral Air Station on 24 June 1999. The instrument contains four coaligned, normal incidence, off-axis parabolic mirrors which illuminate separate Rowland circle spectrograph channels equipped with holographically ruled diffraction gratings and delay line microchannel plate detectors. The telescope mirrors have a 352 x 387 mm aperture and 2245 mm focal length and are attached to actuator assemblies, which provide on-orbit, tip, tilt, and focus control. Two mirrors are coated with silicon carbide (SiC) and two are coated with lithium fluoride over aluminum (Al:LiF). We describe mirror assembly in-flight optical and mechanical performance. On-orbit measurements of the far-ultraviolet point spread function associated with each mirror are compared to expectations based on pre-flight laboratory measurements and modeling using the Optical Surface Analysis Code and surface metrology data. On-orbit imaging data indicate that the mirrors meet their instrument-level requirement of 50 percent and 95 percent slit transmission for the high- and mid-resolution spectrograph entrance slits, respectively. The degradation of mirror reflectivity during satellite integration and test is also discussed. The far-ultraviolet reflectivity of the SiC- and AlLiF-coated mirrors decreased about six percent and three percent, respectively, between coating and launch. Each mirror is equipped with three actuators, which consist of a stepper motor driving a ball screw via a two-stage planetary gear train. We also discuss the mechanical performance of the mirror assemblies, including actuator performance and thermal effects.

Performance of the Far Ultraviolet Spectroscopic Explorer mirror assemblies

NASA Astrophysics Data System (ADS)

Ohl, Raymond G.; Barkhouser, Robert H.; Conard, Steven J.; Friedman, Scott D.; Hampton, Jeffrey; Moos, H. Warren; Nikulla, Paul; Oliveira, Cristina M.; Saha, Timo T.

2000-12-01

The Far Ultraviolet Spectroscopic Explorer is a NASA astrophysics satellite which produces high-resolution spectra in the far-ultraviolet (90.5 - 118.7 nm bandpass) using a high effective area and low background detectors. The observatory was launched on its three-year mission from Cape Canaveral Air Station on 24 June 1999. The instrument contains four co- aligned, normal incidence, off-axis parabolic mirrors which illuminate separate Rowland circle spectrograph channels equipped with holographically ruled diffraction gratings and delay line microchannel plate detectors. The telescope mirrors have a 352 X 387 mm aperture and 2245 mm focal length and are attached to actuator assemblies, which provide on-orbit, tip, tilt, and focus control. Two mirrors are coated with silicon carbide (SiC) and two are coated with lithium fluoride over aluminum (Al:LiF). We describe mirror assembly in-flight optical and mechanical performance. On-orbit measurements of the far-ultraviolet point spread function associated with each mirror are compared to expectations based on pre-flight laboratory measurements and modeling using the Optical Surface Analysis Code and surface metrology data. On-orbit imaging data indicate that the mirrors meet their instrument-level requirement of 50% and 95% slit transmission for the high- and mid-resolution spectrograph entrance slits, respectively. The degradation of mirror reflectivity during satellite integration and test is also discussed. The FUV reflectivity of the SiC- and Al:LiF-coated mirrors decreased about 6% and 3%, respectively, between coating and launch. Each mirror is equipped with three actuators, which consist of a stepper motor driving a ball screw via a two-stage planetary gear train. We also discuss the mechanical performance of the mirror assemblies, including actuator performance and thermal effects.

Spectroscopic Characterization of GEO Satellites with Gunma LOW Resolution Spectrograph

NASA Astrophysics Data System (ADS)

Endo, T.; Ono, H.; Hosokawa, M.; Ando, T.; Takanezawa, T.; Hashimoto, O.

The spectroscopic observation is potentially a powerful tool for understanding the Geostationary Earth Orbit (GEO) objects. We present here the results of an investigation of energy spectra of GEO satellites obtained from a groundbased optical telescope. The spectroscopic observations were made from April to June 2016 with the Gunma LOW resolution Spectrograph and imager (GLOWS) at the Gunma Astronomical Observatory (GAO) in JAPAN. The observation targets consist of eleven different satellites: two weather satellites, four communications satellites, and five broadcasting satellites. All the spectra of those GEO satellites are inferred to be solar-like. A number of well-known absorption features such as H-alpha, H-beta, Na-D,water vapor and oxygen molecules are clearly seen in thewavelength range of 4,000 - 8,000 Å. For comparison, we calculated the intensity ratio of the spectra of GEO satellites to that of the Moon which is the natural satellite of the earth. As a result, the following characteristics were obtained. 1) Some variations are seen in the strength of absorption features of water vapor and oxygen originated by the telluric atmosphere, but any other characteristic absorption features were not found. 2) For all observed satellites, the intensity ratio of the spectrum of GEO satellites decrease as a function of wavelength or to be flat. It means that the spectral reflectance of satellite materials is bluer than that of the Moon. 3) A characteristic dip at around 4,800 Å is found in all observed spectra of a weather satellite. Based on these observations, it is indicated that the characteristics of the spectrum are mainly derived from the solar panels because the apparent area of the solar cell is probably larger than that of the satellite body.

A First for NASA's IRIS: Observing a Gigantic Eruption of Solar Material

NASA Image and Video Library

2014-05-30

Watch a video from this event here: www.flickr.com/photos/gsfc/14118958800/ A coronal mass ejection, or CME, surged off the side of the sun on May 9, 2014, and NASA's newest solar observatory caught it in extraordinary detail. This was the first CME observed by the Interface Region Imaging Spectrograph, or IRIS, which launched in June 2013 to peer into the lowest levels of the sun's atmosphere with better resolution than ever before. Watch the movie to see how a curtain of solar material erupts outward at speeds of 1.5 million miles per hour. Read more: 1.usa.gov/1kp7O4F NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Hubble Space Telescope, Faint Object Spectrograph

NASA Technical Reports Server (NTRS)

1981-01-01

This drawing illustrates the Hubble Space Telescope's (HST's), Faint Object Spectrograph (FOS). The HST's two spectrographs, the Goddard High-Resolution Spectrograph and the FOS, can detect a broader range of wavelengths than is possible from the Earth because there is no atmosphere to absorb certain wavelengths. Scientists can determine the chemical composition, temperature, pressure, and turbulence of the stellar atmosphere producing the light, all from spectral data. The FOC can detect detail in very faint objects, such as those at great distances, and light ranging from ultraviolet to red spectral bands. Both spectrographs operate in essentially the same way. The incoming light passes through a small entrance aperture, then passes through filters and diffraction gratings, that work like prisms. The filter or grating used determines what range of wavelength will be examined and in what detail. Then the spectrograph detectors record the strength of each wavelength band and sends it back to Earth. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Cornecticut, developed the optical system and guidance sensors.

VizieR Online Data Catalog: CONCH-SHELL catalog of nearby M dwarfs (Gaidos+, 2014)

NASA Astrophysics Data System (ADS)

Gaidos, E.; Mann, A. W.; Lepine, S.; Buccino, A.; James, D.; Ansdell, M.; Petrucci, R.; Mauas, P.; Hilton, E. J.

2015-04-01

Lepinet et al. 2011 (J/AJ/142/138) selected candidate M dwarfs as stars that were (i) bright (J<10), (ii) red (V-J>2.7), (iii) had absolute magnitudes or reduced proper motions, proxies for absolute magnitudes, consistent with the main sequence and (iv) infrared Two Micron All-Sky Survey (2MASS; Skrutskie et al. 2006, Cat. II/246) JHKS colours that are consistent with M dwarfs. In this work, we constructed a revised catalogue of J<9 M dwarfs using modified criteria and new photometry from APASS. Spectroscopic observations with a resolution if ~1000 were achieved at the SuperNova Integral Field Spectrograph (SNIFS) on the University of Hawaii 2.2m telescope on Maunakea, Hawaii, the Mark III spectrograph and Boller & Chivens CCDS spectrograph (CCDS) on the 1.3m McGraw-Hill telescope at the MDM Observatory on Kitt Peak, Arizona, the REOSC spectrograph on the 2.15m Jorge Sahade telescope at the Complejo Astronomico El Leoncito Observatory (CASLEO), Argentina, and the RC spectrograph on the 1.9m Radcliffe telescope at the South African Astronomical Observatory. We obtained a total of 3071 spectra of 2583 stars or 86% of the catalog over the span 2002-2014 of more than 11 years. 425 stars were observed twice, 14 stars were observed thrice, and 6 stars had more than four observations. (2 data files).

Analysis of Inter-Moss Loops in the Solar Region with IRIS and SDO AIA: Automatic Event Detection and Characterization

NASA Technical Reports Server (NTRS)

Fayock, Brian; Winebarger, Amy; De Pontieu, Bart; Alexander, Caroline

2016-01-01

The Interface Region Imaging Spectrograph (IRIS), launched in the summer of 2013, is designed specifically to observe and investigate the transition region and adjacent layers of the solar atmosphere, obtaining images in high spatial, temporal, and spectral resolution. Our particular work is focused on the evolution of inter-moss loops, which have been detected in the lower corona by the Atmospheric Imaging Assembly (AIA) and the High-Resolution Coronal Imager (Hi- C), but are known to have foot points below the transition region. With the high-resolution capabilities of IRIS and its Si IV pass band, which measures activity in the upper chromosphere, we can study these magnetic loops in detail and compare their characteristic length and time scales to those obtained from several AIA image sets, particularly the 171, 193, and 211 pass bands. By comparing the results between these four data sets, one can potentially establish a measure of the ionization equilibrium for the location in question. To explore this idea, we found a large, sit-and-stare observation within the IRIS database that fit our specifications. This data set contained a number of well-defined inter-moss loops (by visual inspection) with a cadence less than or equal to that of AIA (approximately 12 seconds). This particular data set was recorded on October 23, 2013 at 07:09:30, lasting for 3219 seconds with a field of view of 120.6 by 128.1 arcseconds, centered on -53.9 by 59.1 arcseconds from disk center. For ease of comparison, the AIA data has been interpolated to match the IRIS cadence and resolution. In the main portion of the poster, we demonstrate the detection of events, the information collected, and the immediate results to the right, showing the progress of an event with green as the start, blue as the peak, and red as the end. Below here, we demonstrate how pixels are combined to form groups. The 3D results are shown to the right

Analysis of Inter-Moss Loops in the Solar Region with IRIS and SDO AIA: Automatic Event Detection and Characterization

NASA Technical Reports Server (NTRS)

Fayock, Brian; Winebarger, Amy; De Pontieu, Bart

2014-01-01

The Interface Region Imaging Spectrograph (IRIS), launched in the summer of 2013, is designed specifically to observe and investigate the transition region and adjacent layers of the solar atmosphere, obtaining images in high spatial, temporal, and spectral resolution. Our particular work is focused on the evolution of inter-moss loops, which have been detected in the lower corona by the Atmospheric Imaging Assembly (AIA) and the High-Resolution Coronal Imager (Hi- C), but are known to have foot points below the transition region. With the high-resolution capabilities of IRIS and its Si IV pass band, which measures activity in the upper chromosphere, we can study these magnetic loops in detail and compare their characteristic length and time scales to those obtained from several AIA image sets, particularly the 171, 193, and 211 pass bands. By comparing the results between these four data sets, one can potentially establish a measure of the ionization equilibrium for the location in question. To explore this idea, we found a large, sit-and-stare observation within the IRIS database that fit our specifications. This data set contained a number of well-defined inter-moss loops (by visual inspection) with a cadence less than or equal to that of AIA (approximately 12 seconds). This particular data set was recorded on October 23, 2013 at 07:09:30, lasting for 3219 seconds with a field of view of 120.6 by 128.1 arcseconds, centered on -53.9 by 59.1 arcseconds from disk center. For ease of comparison, the AIA data has been interpolated to match the IRIS cadence and resolution. In the main portion of the poster, we demonstrate the detection of events, the information collected, and the immediate results to the right, showing the progress of an event with green as the start, blue as the peak, and red as the end. Below here, we demonstrate how pixels are combined to form groups. The 3D results are shown to the right.

Volume phase holographic gratings for the Subaru Prime Focus Spectrograph: performance measurements of the prototype grating set

NASA Astrophysics Data System (ADS)

Barkhouser, Robert H.; Arns, James; Gunn, James E.

2014-08-01

The Prime Focus Spectrograph (PFS) is a major instrument under development for the 8.2 m Subaru telescope on Mauna Kea. Four identical, fixed spectrograph modules are located in a room above one Nasmyth focus. A 55 m fiber optic cable feeds light into the spectrographs from a robotic fiber positioner mounted at the telescope prime focus, behind the wide field corrector developed for Hyper Suprime-Cam. The positioner contains 2400 fibers and covers a 1.3 degree hexagonal field of view. Each spectrograph module will be capable of simultaneously acquiring 600 spectra. The spectrograph optical design consists of a Schmidt collimator, two dichroic beamsplitters to separate the light into three channels, and for each channel a volume phase holographic (VPH) grating and a dual- corrector, modified Schmidt reimaging camera. This design provides a 275 mm collimated beam diameter, wide simultaneous wavelength coverage from 380 nm to 1.26 µm, and good imaging performance at the fast f/1.1 focal ratio required from the cameras to avoid oversampling the fibers. The three channels are designated as the blue, red, and near-infrared (NIR), and cover the bandpasses 380-650 nm (blue), 630-970 nm (red), and 0.94-1.26 µm (NIR). A mosaic of two Hamamatsu 2k×4k, 15 µm pixel CCDs records the spectra in the blue and red channels, while the NIR channel employs a 4k×4k, substrate-removed HAWAII-4RG array from Teledyne, with 15 µm pixels and a 1.7 µm wavelength cutoff. VPH gratings have become the dispersing element of choice for moderate-resolution astronomical spectro- graphs due their potential for very high diffraction efficiency, low scattered light, and the more compact instru- ment designs offered by transmissive dispersers. High quality VPH gratings are now routinely being produced in the sizes required for instruments on large telescopes. These factors made VPH gratings an obvious choice for PFS. In order to reduce risk to the project, as well as fully exploit the performance potential of this technology, a set of three prototype VPH gratings (one each of the blue, red, and NIR designs) was ordered and has been recently delivered. The goal for these prototype units, but not a requirement, was to meet the specifications for the final gratings in order to serve as spares and also as early demonstration and integration articles. In this paper we present the design and specifications for the PFS gratings, the plan and setups used for testing both the prototype and final gratings, and results from recent optical testing of the prototype grating set.

MCT-based SWIR hyperspectral imaging system for evaluation of biological samples

USDA-ARS?s Scientific Manuscript database

Hyperspectral imaging has been shown to be a powerful tool for nondestructive evaluation of biological samples. We recently developed a new line-scan-based shortwave infrared (SWIR) hyperspectral imaging system. Critical sensing components of the system include a SWIR spectrograph, an MCT (HgCdTe) a...

Red to far-red multispectral fluorescence image fusion for detection of fecal contamination on apples

USDA-ARS?s Scientific Manuscript database

This research developed a multispectral algorithm derived from hyperspectral line-scan fluorescence imaging under violet/blue LED excitation for detection of fecal contamination on Golden Delicious apples. Using a hyperspectral line-scan imaging system consisting of an EMCCD camera, spectrograph, an...

Biological sample evaluation using a line-scan based SWIR hyperspectral imaging system

USDA-ARS?s Scientific Manuscript database

A new line-scan hyperspectral imaging system was developed to enable short wavelength infrared (SWIR) imagery for biological sample evaluation. Critical sensing components include a SWIR imaging spectrograph and an HgCdTe (MCT) focal plane array detector. To date, agricultural applications of infra...

Post-focus Instrumentation Of The NST

NASA Astrophysics Data System (ADS)

Cao, Wenda; Gorceix, N.; Andic, A.; Ahn, K.; Coulter, R.; Goode, P.

2009-05-01

The NST (New Solar Telescope), 1.6 m clear aperture, off-axis telescope, is in its commissioning phase at Big Bear Solar Observatory (BBSO). It will be the most capable, largest aperture solar telescope in the US until the 4 m ATST (Advanced Technology Solar Telescope) comes on-line in the middle of the next decade. The NST will be outfitted with state-of-the-art post-focus instrumentation, which currently include Adaptive Optics system (AO), InfraRed Imaging Magnetograph (IRIM), Visible Imaging Magnetograph (VIM), Real-time Image Reconstruction System (RIRS), and Fast Imaging Solar Spectrograph (FISS). A 308 sub-aperture (349-actuator Deformable Mirror) AO system will enable diffraction limited observations over the NST's principal operating wavelengths from 0.4 µm through 1.7 µm. IRIM and VIM are Fabry-Perot based narrow-band tunable filter, which provide high resolution two-dimensional spectroscopic and polarimetric imaging in the near infrared and visible respectively. Using a 32-node parallel computing system, RIRS is capable of performing real-time image reconstruction with one image every minute. FISS is a collaboration between NJIT and Seoul National University to focus on chromosphere dynamics. This instruments would be installed this Summer as a part of the NST commissioning and the implementation of Nysmyth focus instrumentation. Key tasks including optical design, hardware/software integration and subsequent setup/testing on the NST, will be presented in this poster. First light images from the NST will be shown.

Recovering the colour-dependent albedo of exoplanets with high-resolution spectroscopy: from ESPRESSO to the ELT.

NASA Astrophysics Data System (ADS)

Martins, J. H. C.; Figueira, P.; Santos, N. C.; Melo, C.; Garcia Muñoz, A.; Faria, J.; Pepe, F.; Lovis, C.

2018-05-01

The characterization of planetary atmospheres is a daunting task, pushing current observing facilities to their limits. The next generation of high-resolution spectrographs mounted on large telescopes - such as ESPRESSO@VLT and HIRES@ELT - will allow us to probe and characterize exoplanetary atmospheres in greater detail than possible to this point. We present a method that permits the recovery of the colour-dependent reflectivity of exoplanets from high-resolution spectroscopic observations. Determining the wavelength-dependent albedo will provide insight into the chemical properties and weather of the exoplanet atmospheres. For this work, we simulated ESPRESSO@VLT and HIRES@ELT high-resolution observations of known planetary systems with several albedo configurations. We demonstrate how the cross correlation technique applied to theses simulated observations can be used to successfully recover the geometric albedo of exoplanets over a range of wavelengths. In all cases, we were able to recover the wavelength dependent albedo of the simulated exoplanets and distinguish between several atmospheric models representing different atmospheric configurations. In brief, we demonstrate that the cross correlation technique allows for the recovery of exoplanetary albedo functions from optical observations with the next generation of high-resolution spectrographs that will be mounted on large telescopes with reasonable exposure times. Its recovery will permit the characterization of exoplanetary atmospheres in terms of composition and dynamics and consolidates the cross correlation technique as a powerful tool for exoplanet characterization.

The SED Machine: A Robotic Spectrograph for Fast Transient Classification

NASA Astrophysics Data System (ADS)

Blagorodnova, Nadejda; Neill, James D.; Walters, Richard; Kulkarni, Shrinivas R.; Fremling, Christoffer; Ben-Ami, Sagi; Dekany, Richard G.; Fucik, Jason R.; Konidaris, Nick; Nash, Reston; Ngeow, Chow-Choong; Ofek, Eran O.; O’ Sullivan, Donal; Quimby, Robert; Ritter, Andreas; Vyhmeister, Karl E.

2018-03-01

Current time domain facilities are finding several hundreds of transient astronomical events a year. The discovery rate is expected to increase in the future as soon as new surveys such as the Zwicky Transient Facility (ZTF) and the Large Synoptic Sky Survey (LSST) come online. Presently, the rate at which transients are classified is approximately one order or magnitude lower than the discovery rate, leading to an increasing “follow-up drought”. Existing telescopes with moderate aperture can help address this deficit when equipped with spectrographs optimized for spectral classification. Here, we provide an overview of the design, operations and first results of the Spectral Energy Distribution Machine (SEDM), operating on the Palomar 60-inch telescope (P60). The instrument is optimized for classification and high observing efficiency. It combines a low-resolution (R ∼ 100) integral field unit (IFU) spectrograph with “Rainbow Camera” (RC), a multi-band field acquisition camera which also serves as multi-band (ugri) photometer. The SEDM was commissioned during the operation of the intermediate Palomar Transient Factory (iPTF) and has already lived up to its promise. The success of the SEDM demonstrates the value of spectrographs optimized for spectral classification.

Performance of the FOS and GHRS Pt/(Cr)-Ne Hollow-cathode Lamps after their Return from Space and Comparison with Archival Data

NASA Technical Reports Server (NTRS)

Kerber, Florian; Lindler, Don; Bristow, Paul; Lembke, Dominik; Nave, Gillian; Reader, Joseph; Sansonetti, Craig J.; Heap, Sara R.; Rosa, Michael R.; Wood, H. John

2006-01-01

The Space Telescope European Coordinating Facility (ST-ECF) and National Institute of Standards and Technology (NIST) are collaborating to study hollow cathode calibration lamps as used onboard the Hubble Space Telescope (HST). As part of the STIS Calibration Enhancement (STIS-CE) Project we are trying to improve our understanding of the performance of hollow cathode lamps and the physical processes involved in their long term operation. The original flight lamps from the Faint Object Spectrograph (FOS) and the Goddard High Resolution Spectrograph (GHRS) are the only lamps that have ever been returned to Earth after extended operation in space. We have taken spectra of all four lamps using NIST s 10.7-m normal-incidence spectrograph and Fourier transform spectrometer (FTS) optimized for use in the ultraviolet (UV). These spectra, together with spectra archived from six years of on-orbit operations and pre-launch spectra, provide a unique data set - covering a period of about 20 years - for studying aging effects in these lamps. Our findings represent important lessons for the choice and design of calibration sources and their operation in future UV and optical spectrographs in space.

Microchannel plate life testing for UV spectroscopy instruments

NASA Astrophysics Data System (ADS)

Darling, N. T.; Siegmund, O. H. W.; Curtis, T.; McPhate, J.; Tedesco, J.; Courtade, S.; Holsclaw, G.; Hoskins, A.; Al Dhafri, S.

2017-08-01

The Emirates Mars Mission (EMM) UV Spectrograph (EMUS) is a far ultraviolet (102 nm to 170 nm) imaging spectrograph for characterization of the Martian exosphere and thermosphere. Imaging is accomplished by a photon counting open-face microchannel plate (MCP) detector using a cross delay line (XDL) readout. An MCP gain stabilization ("scrub") followed by lifetime spectral line burn-in simulation has been completed on a bare MCP detector at SSL. Gain and sensitivity stability of better than 7% has been demonstrated for total dose of 2.5 × 1012 photons cm-2 (2 C · cm-2 ) at 5.5 kHz mm-2 counting rates, validating the efficacy of an initial low gain full-field scrub.

MUSE field splitter unit: fan-shaped separator for 24 integral field units

NASA Astrophysics Data System (ADS)

Laurent, Florence; Renault, Edgard; Anwand, Heiko; Boudon, Didier; Caillier, Patrick; Kosmalski, Johan; Loupias, Magali; Nicklas, Harald; Seifert, Walter; Salaun, Yves; Xu, Wenli

2014-07-01

MUSE (Multi Unit Spectroscopic Explorer) is a second generation Very Large Telescope (VLT) integral field spectrograph developed for the European Southern Observatory (ESO). It combines a 1' x 1' field of view sampled at 0.2 arcsec for its Wide Field Mode (WFM) and a 7.5"x7.5" field of view for its Narrow Field Mode (NFM). Both modes will operate with the improved spatial resolution provided by GALACSI (Ground Atmospheric Layer Adaptive Optics for Spectroscopic Imaging), that will use the VLT deformable secondary mirror and 4 Laser Guide Stars (LGS) foreseen in 2015. MUSE operates in the visible wavelength range (0.465-0.93 μm). A consortium of seven institutes is currently commissioning MUSE in the Very Large Telescope for the Preliminary Acceptance in Chile, scheduled for September, 2014. MUSE is composed of several subsystems which are under the responsibility of each institute. The Fore Optics derotates and anamorphoses the image at the focal plane. A Splitting and Relay Optics feed the 24 identical Integral Field Units (IFU), that are mounted within a large monolithic instrument mechanical structure. Each IFU incorporates an image slicer, a fully refractive spectrograph with VPH-grating and a detector system connected to a global vacuum and cryogenic system. During 2012 and 2013, all MUSE subsystems were integrated, aligned and tested to the P.I. institute at Lyon. After successful PAE in September 2013, MUSE instrument was shipped to the Very Large Telescope in Chile where it was aligned and tested in ESO integration hall at Paranal. After, MUSE was directly transferred in monolithic way onto VLT telescope where the first light was achieved. This paper describes the MUSE main optical component: the Field Splitter Unit. It splits the VLT image into 24 subfields and provides the first separation of the beam for the 24 Integral Field Units. This talk depicts its manufacturing at Winlight Optics and its alignment into MUSE instrument. The success of the MUSE alignment is demonstrated by the excellent results obtained onto MUSE positioning, image quality and throughput onto the sky. MUSE commissioning at the VLT is planned for September, 2014.

Status of the Stratospheric Observatory for Infrared Astronomy (SOFIA)

NASA Astrophysics Data System (ADS)

Gehrz, R. D.; Becklin, E. E.; de Buizer, J.; Herter, T.; Keller, L. D.; Krabbe, A.; Marcum, P. M.; Roellig, T. L.; Sandell, G. H. L.; Temi, P.; Vacca, W. D.; Young, E. T.; Zinnecker, H.

2011-09-01

The Stratospheric Observatory for Infrared Astronomy (SOFIA), a joint US/German project, is a 2.5-m infrared airborne telescope carried by a Boeing 747-SP that flies in the stratosphere at altitudes as high as 45,000 ft (13.72 km). This facility is capable of observing from 0.3 μm to 1.6 mm with an average transmission greater than 80% averaged over all wavelengths. SOFIA will be staged out of the NASA Dryden Flight Research Center aircraft operations facility at Palmdale, CA. The SOFIA Science Mission Operations (SMO) will be located at NASA Ames Research Center, Moffett Field, CA. First science flights began in 2010 and a full operations schedule of up to one hundred 8 to 10 hour-long flights per year will be reached by 2014. The observatory is expected to operate until the mid-2030s. SOFIA's initial complement of seven focal plane instruments includes broadband imagers, moderate-resolution spectrographs that will resolve broad features due to dust and large molecules, and high-resolution spectrometers capable of studying the kinematics of atomic and molecular gas at sub-km/s resolution. We describe the SOFIA facility and outline the opportunities for observations by the general scientific community and for future instrumentation development. The operational characteristics of the SOFIA first-generation instruments are summarized. The status of the flight test program is discussed and we show First Light images obtained at wavelengths from 5.4 to 37 μm with the FORCAST imaging camera. Additional information about SOFIA is available at http://www.sofia.usra.edu and http://www.sofia.usra.edu/Science/docs/SofiaScienceVision051809-1.pdf.

VizieR Online Data Catalog: The Carnegie-Chicago Hubble Program. II. IC 1613 (Hatt+, 2017)

NASA Astrophysics Data System (ADS)

Hatt, D.; Beaton, R. L.; Freedman, W. L.; Madore, B. F.; Jang, I.-S.; Hoyt, T. J.; Lee, M. G.; Monson, A. J.; Rich, J. A.; Scowcroft, V.; Seibert, M.

2018-04-01

Observations of IC 1613 were obtained on 2015 June 12 using the Inamori-Magellan Areal Camera and Spectrograph (IMACS) on the 6.5m Magellan-Baade telescope at Las Campanas Observatory. We obtain a 15.46'x15.46' field of view with resolution of 0.2"/pixel and observed in the BVI filters. See section 2.1.1. We have made use of archival imaging of IC 1613 taken from the Local Cosmology from Isolated Dwarfs program (PID:GO10505, PI: Gallart; Gallart 2005, LCID). A single field was imaged over 24 orbits between 2006 August 28 and 30 approximately 5' west of the center of IC 1613 using the HST ACS/WFC instrument, which provides a 202"x202" field of view with 0.05"/pixel resolution. Each orbit was divided between two ~1200s exposures in the F475W and F814W passbands, resulting in 48 epochs per filter. See section 2.1.2. We obtained near-infrared imaging over 24 orbits between 2014 December 17 and 18 using the HST WFC3/IR instrument (PID:GO13691, PI: Freedman; Freedman W. 2014 HST Proposal). The orbits were divided between two overlapping 136"x123" WFC3/IR pointings with a native resolution of 0.135"/pixel. See section 2.1.3. In parallel with the observations described in the previous section were 24 orbits with the HST ACS/WFC instrument (PID:GO13691, PI: Freedman; Freedman 2014 W. HST Proposal). Each exposure in F606W and F814W spanned ~500s. See section 2.1.4. (2 data files).

Status of the JWST Science Instrument Payload

NASA Technical Reports Server (NTRS)

Greenhouse, Matt

2016-01-01

The James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM) system consists of five sensors (4 science): Mid-Infrared Instrument (MIRI), Near Infrared Imager and Slitless Spectrograph (NIRISS), Fine Guidance Sensor (FGS), Near InfraRed Camera (NIRCam), Near InfraRed Spectrograph (NIRSpec); and nine instrument support systems: Optical metering structure system, Electrical Harness System; Harness Radiator System, ISIM Electronics Compartment, ISIM Remote Services Unit, Cryogenic Thermal Control System, Command and Data Handling System, Flight Software System, Operations Scripts System.

Integrating TV/digital data spectrograph system

NASA Technical Reports Server (NTRS)

Duncan, B. J.; Fay, T. D.; Miller, E. R.; Wamsteker, W.; Brown, R. M.; Neely, P. L.

1975-01-01

A 25-mm vidicon camera was previously modified to allow operation in an integration mode for low-light-level astronomical work. The camera was then mated to a low-dispersion spectrograph for obtaining spectral information in the 400 to 750 nm range. A high speed digital video image system was utilized to digitize the analog video signal, place the information directly into computer-type memory, and record data on digital magnetic tape for permanent storage and subsequent analysis.

VizieR Online Data Catalog: MUSCLES Treasury Survey. IV. M dwarf UV fluxes (Youngblood+, 2017)

NASA Astrophysics Data System (ADS)

Youngblood, A.; France, K.; Loyd, R. O. P.; Brown, A.; Mason, J. P.; Schneider, P. C.; Tilley, M. A.; Berta-Thompson, Z. K.; Buccino, A.; Froning, C. S.; Hawley, S. L.; Linsky, J.; Mauas, P. J. D.; Redfield, S.; Kowalski, A.; Miguel, Y.; Newton, E. R.; Rugheimer, S.; Segura, A.; Roberge, A.; Vieytes, M.

2018-02-01

We selected stars with HST UV spectra and ground-based optical spectra either obtained directly by us or available in the VLT/XSHOOTER or Keck/HIRES public archives. Several targets have spectroscopic data obtained with the Dual Imaging Spectrograph (DIS) on the ARC 3.5m telescope at Apache Point Observatory (APO), R~2500, or the REOSC echelle spectrograph on the 2.15m telescope at Complejo Astronomico El Leoncito (CASLEO), R~12000, within a day or two of the HST observations. We also gathered spectra of GJ1132, GJ1214, and Proxima Cen on the nights of 2016 March 7-9 using the MIKE echelle spectrograph on the Magellan Clay telescope. (2 data files).

Food quality assessment by NIR hyperspectral imaging

NASA Astrophysics Data System (ADS)

Whitworth, Martin B.; Millar, Samuel J.; Chau, Astor

2010-04-01

Near infrared reflectance (NIR) spectroscopy is well established in the food industry for rapid compositional analysis of bulk samples. NIR hyperspectral imaging provides new opportunities to measure the spatial distribution of components such as moisture and fat, and to identify and measure specific regions of composite samples. An NIR hyperspectral imaging system has been constructed for food research applications, incorporating a SWIR camera with a cooled 14 bit HgCdTe detector and N25E spectrograph (Specim Ltd, Finland). Samples are scanned in a pushbroom mode using a motorised stage. The system has a spectral resolution of 256 pixels covering a range of 970-2500 nm and a spatial resolution of 320 pixels covering a swathe adjustable from 8 to 300 mm. Images are acquired at a rate of up to 100 lines s-1, enabling samples to be scanned within a few seconds. Data are captured using SpectralCube software (Specim) and analysed using ENVI and IDL (ITT Visual Information Solutions). Several food applications are presented. The strength of individual absorbance bands enables the distribution of particular components to be assessed. Examples are shown for detection of added gluten in wheat flour and to study the effect of processing conditions on fat distribution in chips/French fries. More detailed quantitative calibrations have been developed to study evolution of the moisture distribution in baguettes during storage at different humidities, to assess freshness of fish using measurements of whole cod and fillets, and for prediction of beef quality by identification and separate measurement of lean and fat regions.

MULTI-WAVELENGTH STUDY OF TRANSITION REGION PENUMBRAL SUBARCSECOND BRIGHT DOTS USING IRIS AND NST

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

Deng, Na; Liu, Chang; Xu, Yan

Using high-resolution transition region (TR) observations taken by the Interface Region Imaging Spectrograph ( IRIS ) mission, Tian et al. revealed numerous short-lived subarcsecond bright dots (BDs) above sunspots (mostly located in the penumbrae), which indicate yet unexplained small-scale energy releases. Moreover, whether or not these subarcsecond TR brightenings have any signature in the lower atmosphere and how they are formed are still not fully resolved. This paper presents a multi-wavelength study of the TR penumbral BDs using a coordinated observation of a near disk center sunspot with IRIS and the 1.6 m New Solar Telescope (NST) at the Bigmore » Bear Solar Observatory. NST provides high-resolution chromospheric and photospheric observations with narrowband H α imaging spectroscopy and broadband TiO images, respectively, complementary to IRIS TR observations. A total of 2692 TR penumbral BDs are identified from a 37 minute time series of IRIS 1400 Å slit-jaw images. Their locations tend to be associated more with downflowing and darker fibrils in the chromosphere, and weakly associated with bright penumbral features in the photosphere. However, temporal evolution analyses of the BDs show that there is no consistent and convincing brightening response in the chromosphere. These results are compatible with a formation mechanism of the TR penumbral BDs by falling plasma from coronal heights along more vertical and dense magnetic loops. The BDs may also be produced by small-scale impulsive magnetic reconnection taking place sufficiently high in the atmosphere that has no energy release in the chromosphere.« less

VizieR Online Data Catalog: IN-SYNC. IV. YSOs in Orion A (Da Rio+, 2016)

NASA Astrophysics Data System (ADS)

da Rio, N.; Tan, J. C.; Covey, K. R.; Cottaar, M.; Foster, J. B.; Cullen, N. C.; Tobin, J. J.; Kim, J. S.; Meyer, M. R.; Nidever, D. L.; Stassun, K. G.; Chojnowski, S. D.; Flaherty, K. M.; Majewski, S.; Skrutskie, M. F.; Zasowski, G.; Pan, K.

2016-04-01

Observations were carried out in 2013 December and 2014 January, with the APOGEE spectrograph on the Sloan 2.5m telescope. APOGEE is a fiber-fed multiobject infrared spectrograph, operating in H band in the range 1.5μm<~λ<~1.6μm, capable of obtaining spectra of up to 320 sources simultaneously on a corrected FOV of ~7 square degrees, and with a resolution R~22500. Fifteen APOGEE plates, on five positions in the sky, have been designed to cover the Orion A region as shown in Figure 1. See section 2 for further explanations. (2 data files).

Development of a slicer integral field unit for the existing optical imaging spectrograph FOCAS

NASA Astrophysics Data System (ADS)

Ozaki, Shinobu; Tanaka, Yoko; Hattori, Takashi; Mitsui, Kenji; Fukusima, Mitsuhiro; Okada, Norio; Obuchi, Yoshiyuki; Miyazaki, Satoshi; Yamashita, Takuya

2012-09-01

We are developing an integral field unit (IFU) with an image slicer for the existing optical imaging spectrograph, Faint Object Camera And Spectrograph (FOCAS), on the Subaru Telescope. Basic optical design has already finished. The slice width is 0.4 arcsec, slice number is 24, and field of view is 13.5x 9.6 arcsec. Sky spectra separated by about 3 arcmin from an object field can be simultaneously obtained, which allows us precise background subtraction. The IFU will be installed as a mask plate and set by the mask exchanger mechanism of FOCAS. Slice mirrors, pupil mirrors and slit mirrors are all made of glass, and their mirror surfaces are fabricated by polishing. Multilayer dielectric reflective coating with high reflectivity (< 98%) is made on each mirror surface. Slicer IFU consists of many mirrors which need to be arraigned with high accuracy. For such alignment, we will make alignment jigs and mirror holders made with high accuracy. Some pupil mirrors need off-axis ellipsoidal surfaces to reduce aberration. We are conducting some prototyping works including slice mirrors, an off-axis ellipsoidal surface, alignment jigs and a mirror support. In this paper, we will introduce our project and show those prototyping works.

Blind Spectroscopic Galaxy Surveys Using an Ultra-Wide-Band Imaging Spectrograph on AtLAST and LST

NASA Astrophysics Data System (ADS)

Kohno, Kotaro

2018-01-01

A novel approach to elucidation of cosmic star formation history is a blind search for CO and [CII] emissions using a ultra-wide-band imaging spectrograph on the future large submm telescopes like AtLAST and LST. In particular, searching for [CII] emitters in the appropriate frequency range allows us to sample those sources very efficiently for a redshift range of 3.5 to 9 (190 to 420 GHz), reaching the star-formation in the EoR. Further, spectroscopic analysis of CO in the lower frequency bands will constrain the evolution of CO luminosity functions across cosmic time. We conducted a feasibility study of ``CO/[CII] tomography'' based on a mock galaxy catalog containing 1.4 million objects drawn from the S(3) -SAX (Obreschkow et al. 2009). We find that a blind spectroscopic survey using a 50-m telescope equipped with a 100-pixel imaging spectrograph, which covers 70-370 GHz simultaneously, will be promising indeed. A survey of 2 deg(2) in 1,000 hr (on-source) will uncover > 10^5 line-emitting galaxies in total, including 10^3 [CII] emitters in the EoR (Tamura et al., in prep.). Wider surveys (10 deg^2 or wider) will also be discussed for RSD science cases.

Design of FHiRE: the Fiber High Resolution Echelle Spectrograph

NASA Astrophysics Data System (ADS)

Pierce, Michael J.; McLane, Jacob N.; Pilachowski, C. A.; Kobulnicky, Henry; Jang-Condell, Hannah

2018-01-01

The enormous success of the Kepler mission in the discovery of transiting exoplanets implies that the majority of stars have planetary systems. NASA's upcomming Transiting Exoplanet Survey Satellite (TESS) is designed to survey the brightest stars over the entire sky, systems that are accessible to spectroscopic follow-up with mid-sized telescopes. We have undertaken the development of a precision radial velocity spectrograph with the goal of providing ground-based suppoert for TESS. The instrument, known as FHiRE (Fiber High Resolution Echelle spectrograph), is being developed in collaboration with Indiana University and will deployed at the 2.3-meter telescope of the Wyoming InfraRed Observatory (WIRO). FHiRE features a traditional white pupil echelle design with R ~ 60,000 that is fed via two optical fibers from the telescope. Both the science fiber and a simultaneously sampled Thorium-Argon comparison fiber will make use of double mode scramblers. FHiRE itself will be housed within a vacuum enclosure in order to minimize any temperatue variations of the instrument and maximize its radial velocity precision. Together, these two features should enable FHiRE to reach a long-term velocity precision of < 1 m/s. We present the design of FHiRE and its expected performance. In a companion poster (Jang-Condell et al.) we will present the exoplanet science goals of the project.

A solar radio dynamic spectrograph with flexible temporal-spectral resolution

NASA Astrophysics Data System (ADS)

Du, Qing-Fu; Chen, Lei; Zhao, Yue-Chang; Li, Xin; Zhou, Yan; Zhang, Jun-Rui; Yan, Fa-Bao; Feng, Shi-Wei; Li, Chuan-Yang; Chen, Yao

2017-09-01

Observation and research on solar radio emission have unique scientific values in solar and space physics and related space weather forecasting applications, since the observed spectral structures may carry important information about energetic electrons and underlying physical mechanisms. In this study, we present the design of a novel dynamic spectrograph that has been installed at the Chashan Solar Radio Observatory operated by the Laboratory for Radio Technologies, Institute of Space Sciences at Shandong University. The spectrograph is characterized by real-time storage of digitized radio intensity data in the time domain and its capability to perform off-line spectral analysis of the radio spectra. The analog signals received via antennas and amplified with a low-noise amplifier are converted into digital data at a speed reaching up to 32 k data points per millisecond. The digital data are then saved into a high-speed electronic disk for further off-line spectral analysis. Using different word lengths (1-32 k) and time cadences (5 ms-10 s) for off-line fast Fourier transform analysis, we can obtain the dynamic spectrum of a radio burst with different (user-defined) temporal (5 ms-10 s) and spectral (3 kHz˜320 kHz) resolutions. This enables great flexibility and convenience in data analysis of solar radio bursts, especially when some specific fine spectral structures are under study.

The assembly, calibration, and preliminary results from the Colorado high-resolution Echelle stellar spectrograph (CHESS)

NASA Astrophysics Data System (ADS)

Hoadley, Keri; France, Kevin; Nell, Nicholas; Kane, Robert; Schultz, Ted; Beasley, Matthew; Green, James; Kulow, Jen; Kersgaard, Eliot; Fleming, Brian

2014-07-01

The Colorado High-resolution Echelle Stellar Spectrograph (CHESS) is a far ultraviolet (FUV) rocket-borne experiment designed to study the atomic-to-molecular transitions within translucent interstellar clouds. CHESS is an objective echelle spectrograph operating at f/12.4 and resolving power of 120,000 over a band pass of 100 - 160 nm. The echelle flight grating is the product of a research and development project with LightSmyth Inc. and was coated at Goddard Space Flight Center (GSFC) with Al+LiF. It has an empirically-determined groove density of 71.67 grooves/mm. At the Center for Astrophysics and Space Astronomy (CASA) at the University of Colorado (CU), we measured the efficiencies of the peak and adjacent dispersion orders throughout the 90 - 165 nm band pass to characterize the behavior of the grating for pre-flight calibrations and to assess the scattered-light behavior. The crossdispersing grating, developed and ruled by Horiba Jobin-Yvon, is a holographically-ruled, low line density (351 grooves/mm), powered optic with a toroidal surface curvature. The CHESS cross-disperser was also coated at GSFC; Cr+Al+LiF was deposited to enhance far-UV efficiency. Results from final efficiency and reflectivity measurements of both optics are presented. We utilize a cross-strip anode microchannel plate (MCP) detector built by Sensor Sciences to achieve high resolution (25 μm spatial resolution) and data collection rates (~ 106 photons/second) over a large format (40mm round, digitized to 8k x 8k) for the first time in an astronomical sounding rocket flight. The CHESS instrument was successfully launched from White Sands Missile Range on 24 May 2014. We present pre-flight sensitivity, effective area calculations, lab spectra and calibration results, and touch on first results and post-flight calibration plans.