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).

The third flight of the Colorado high-resolution echelle stellar spectrograph (CHESS): improvements, calibrations, and preliminary results

NASA Astrophysics Data System (ADS)

Kruczek, Nicholas; Nell, Nicholas; France, Kevin; Hoadley, Keri; Fleming, Brian; Kane, Robert; Ulrich, Stefan; Egan, Arika; Beatty, Dawson

2017-08-01

In this proceeding, we describe the scientific motivation and technical development of the Colorado HighResolution Echelle Stellar Spectrograph (CHESS), focusing on the hardware advancements and testing of components for the third launch of the payload (CHESS-3). CHESS is a far ultraviolet rocket-borne instrument designed to study the atomic-to-molecular transitions within translucent cloud regions in the interstellar medium. CHESS is an objective echelle spectrograph, which uses a mechanically-ruled echelle and a powered (f/12.4) crossdispersing grating, and is designed to achieve a resolving power R > 100,000 over the bandpass λλ 1000-1600 Å. Results from final efficiency and reflectivity measurements for the optical components of CHESS-3 are presented. An important role of sounding rocket experiments is the testing and verification of the space flight capabilities of experimental technologies. CHESS-3 utilizes a 40mm-diameter cross-strip anode microchannel plate detector fabricated by Sensor Sciences LLC, capable of achieving high spatial resolution and a high global count rate (˜1 MHz). We present pre-flight laboratory spectra and calibration results, including wavelength solution and resolving power of the instrument. The fourth launch of CHESS (CHESS-4) will demonstrate a δ-doped CCD, assembled in collaboration with the Microdevices Laboratory at JPL and Arizona State University. In support of CHESS-4, the CHESS-3 payload included a photomultiplier tube, used as a secondary confirmation of the optical alignment of the payload during flight. CHESS-3 launched on 26 June 2017 aboard NASA/CU sounding rocket mission 36.323 UG. We present initial flight results for the CHESS-3 observation of the β1 Scorpii sightline.

The "+" for CRIRES: enabling better science at infrared wavelength and high spectral resolution at the ESO VLT

NASA Astrophysics Data System (ADS)

Dorn, Reinhold J.; Follert, Roman; Bristow, Paul; Cumani, Claudio; Eschbaumer, Siegfried; Grunhut, Jason; Haimerl, Andreas; Hatzes, Artie; Heiter, Ulrike; Hinterschuster, Renate; Ives, Derek J.; Jung, Yves; Kerber, Florian; Klein, Barbara; Lavaila, Alexis; Lizon, Jean Louis; Löwinger, Tom; Molina-Conde, Ignacio; Nicholson, Belinda; Marquart, Thomas; Oliva, Ernesto; Origlia, Livia; Pasquini, Luca; Paufique, Jérôme; Piskunov, Nikolai; Reiners, Ansgar; Seemann, Ulf; Stegmeier, Jörg; Stempels, Eric; Tordo, Sebastien

2016-08-01

The adaptive optics (AO) assisted CRIRES instrument is an IR (0.92 - 5.2 μm) high-resolution spectrograph was in operation from 2006 to 2014 at the Very Large Telescope (VLT) observatory. CRIRES was a unique instrument, accessing a parameter space (wavelength range and spectral resolution) up to now largely uncharted. It consisted of a single-order spectrograph providing long-slit (40 arcsecond) spectroscopy with a resolving power up to R=100 000. However the setup was limited to a narrow, single-shot, spectral range of about 1/70 of the central wavelength, resulting in low observing efficiency for many scientific programmes requiring a broad spectral coverage. The CRIRES upgrade project, CRIRES+, transforms this VLT instrument into a cross-dispersed spectrograph to increase the simultaneously covered wavelength range by a factor of ten. A new and larger detector focal plane array of three Hawaii 2RG detectors with 5.3 μm cut-off wavelength will replace the existing detectors. For advanced wavelength calibration, custom-made absorption gas cells and an etalon system will be added. A spectro-polarimetric unit will allow the recording of circular and linear polarized spectra. This upgrade will be supported by dedicated data reduction software allowing the community to take full advantage of the new capabilities offered by CRIRES+. CRIRES+ has now entered its assembly and integration phase and will return with all new capabilities by the beginning of 2018 to the Very Large Telescope in Chile. This article will provide the reader with an update of the current status of the instrument as well as the remaining steps until final installation at the Paranal Observatory.

An overview of instrumentation for the Large Binocular Telescope

NASA Astrophysics Data System (ADS)

Wagner, R. Mark

2006-06-01

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.

An overview of instrumentation for the Large Binocular Telescope

NASA Astrophysics Data System (ADS)

Wagner, R. Mark

2004-09-01

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'x 27') UB/VRI optimized 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\\arcmin\\ 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'x 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 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 beam combiner with visible and near-infrared imagers 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.

An overview of instrumentation for the Large Binocular Telescope

NASA Astrophysics Data System (ADS)

Wagner, R. Mark

2008-07-01

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.

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.

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;

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 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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

High resolution spectrograph. [for LST

NASA Technical Reports Server (NTRS)

Peacock, K.

1975-01-01

The high resolution spectrograph (HRS) is designed to be used with the Large Space Telescope (LST) for the study of spectra of point and extended targets in the spectral range 110 to 410 nm. It has spectral resolutions of 1,000; 30,000; and 100,000 and has a field of view as large as 10 arc sec. The spectral range and resolution are selectable using interchangeable optical components and an echelle spectrograph is used to display a cross dispersed spectrum on the photocathode of either of 2 SEC orthicon image tubes. Provisions are included for wavelength calibration, target identification and acquisition and thermal control. The system considerations of the instrument are described.

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.

Experimental Study of an Advanced Concept of Moderate-resolution Holographic Spectrographs

NASA Astrophysics Data System (ADS)

Muslimov, Eduard; Valyavin, Gennady; Fabrika, Sergei; Musaev, Faig; Galazutdinov, Gazinur; Pavlycheva, Nadezhda; Emelianov, Eduard

2018-07-01

We present the results of an experimental study of an advanced moderate-resolution spectrograph based on a cascade of narrow-band holographic gratings. The main goal of the project is to achieve a moderately high spectral resolution with R up to 5000 simultaneously in the 4300–6800 Å visible spectral range on a single standard CCD, together with an increased throughput. The experimental study consisted of (1) resolution and image quality tests performed using the solar spectrum, and (2) a total throughput test performed for a number of wavelengths using a calibrated lab monochromator. The measured spectral resolving power reaches values over R > 4000 while the experimental throughput is as high as 55%, which agrees well with the modeling results. Comparing the obtained characteristics of the spectrograph under consideration with the best existing spectrographs, we conclude that the used concept can be considered as a very competitive and cheap alternative to the existing spectrographs of the given class. We propose several astrophysical applications for the instrument and discuss the prospect of creating its full-scale version.

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.

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.

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.

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.

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.

The Spartan-281 Far Ultraviolet Imaging Spectrograph

NASA Technical Reports Server (NTRS)

Carruthers, George R.; Heckathorn, Harry M.; Dufour, Reginald J.; Opal, Chet B.; Raymond, John C.

1988-01-01

The U.S. Naval Research Laboratory's Far Ultraviolet Imaging Spectrograph (FUVIS), currently under development for flight as a Spartan shuttle payload, is designed to perform spectroscopy of diffuse sources in the FUV with very high sensitivity and moderate spatial and spectral resolution. Diffuse nebulae, the general galactic background radiation, and artificially induced radiation associated with the Space Shuttle vehicle are sources of particular interest. The FUVIS instrument will cover the wavelength range of 970-2000 A with selectable resolutions of 5 and 30 A. It is a slit imaging spectrograph having 3 arcmin spatial resolution along its 2.7 deg long slit.

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.

Enhanced Exoplanet Biosignature from an Interferometer Addition to Low Resolution Spectrographs

NASA Astrophysics Data System (ADS)

Erskine, D. J.; Muirhead, P. S.; Vanderburg, A. M.; Szentgyorgyi, A.

2017-12-01

The absorption spectral signature of many atmospheric molecules consists of a group of 40 or so lines that are approximately periodic due to the physics of molecular vibration. This is fortuitous for detecting atmospheric features in an exoEarth, since it has a similar periodic nature as an interferometer's transmission, which is sinusoidal. The period (in wavenumbers) of the interferometer is selectable, being inversely proportional to the delay (in cm). We show that the addition of a small interferometer of 0.6 cm delay to an existing dispersive spectrograph can greatly enhance the detection of molecular features, by several orders of magnitude for initially low resolution spectrographs. We simulate the Gemini Planet Imager measuring a telluric spectrum having native resolution of 40 and 70 in the 1.65 micron and 2 micron bands. These low resolutions are insufficient to resolve the fine features of the molecular feature group. However, the addition of a 0.6 cm delay outside the spectrograph and in series with it increases the local amplitude of the signal to a level similar to a R=4400 (at 1.65 micron) or R=3900 (at 2 micron) classical spectrograph. Prepared by LLNL under Contract DE-AC52-07NA27344.

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.

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 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.

Second generation spectrograph for the Hubble Space Telescope

NASA Astrophysics Data System (ADS)

Woodgate, B. E.; Boggess, A.; Gull, T. R.; Heap, S. R.; Krueger, V. L.; Maran, S. P.; Melcher, R. W.; Rebar, F. J.; Vitagliano, H. D.; Green, R. F.; Wolff, S. C.; Hutchings, J. B.; Jenkins, E. B.; Linsky, J. L.; Moos, H. W.; Roesler, F.; Shine, R. A.; Timothy, J. G.; Weistrop, D. E.; Bottema, M.; Meyer, W.

1986-01-01

The preliminary design for the Space Telescope Imaging Spectrograph (STIS), which has been selected by NASA for definition study for future flight as a second-generation instrument on the Hubble Space Telescope (HST), is presented. STIS is a two-dimensional spectrograph that will operate from 1050 A to 11,000 A at the limiting HST resolution of 0.05 arcsec FWHM, with spectral resolutions of 100, 1200, 20,000, and 100,000 and a maximum field-of-view of 50 x 50 arcsec. Its basic operating modes include echelle model, long slit mode, slitless spectrograph mode, coronographic spectroscopy, photon time-tagging, and direct imaging. Research objectives are active galactic nuclei, the intergalactic medium, global properties of galaxies, the origin of stellar systems, stelalr spectral variability, and spectrographic mapping of solar system processes.

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.

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.

The 4MOST facility control software

NASA Astrophysics Data System (ADS)

Pramskiy, Alexander; Mandel, Holger; Rothmaier, Florian; Stilz, Ingo; Winkler, Roland; Hahn, Thomas

2016-07-01

The 4-m Multi-Object Spectrographic Telescope (4MOST) is one high-resolution (R 18000) and two lowresolution (R fi 5000) spectrographs covering the wavelength range between 390 and 950 nm. The spectrographs will be installed on ESO VISTA telescope and will be fed by approximately 2400 fibres. The instrument is capable to simultaneously obtain spectra of about 2400 objects distributed over an hexagonal field-of-view of four square degrees. This paper aims at giving an overview of the control software design, which is based on the standard ESO VLT software architecture and customised to fit the needs of the 4MOST instrument. In particular, the facility control software is intended to arrange the precise positioning of the fibres, to schedule and observe many surveys in parallel, and to combine the output from the three spectrographs. Moreover, 4MOST's software will include user-friendly graphical user interfaces that enable users to interact with the facility control system and to monitor all data-taking and calibration tasks of the instrument. A secondary guiding system will be implemented to correct for any fibre exure and thus to improve 4MOST's guiding performance. The large amount of fibres requires the custom design of data exchange to avoid performance issues. The observation sequences are designed to use spectrographs in parallel with synchronous points for data exchange between subsystems. In order to control hardware devices, Programmable Logic Controller (PLC) components will be used, the new standard for future instruments at ESO.

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.

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.

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.

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.

Instruments at the Lowell Observatory Discovery Channel Telescope (DCT)

NASA Astrophysics Data System (ADS)

Jacoby, George H.; Bida, Thomas A.; Fischer, Debra; Horch, Elliott; Kutyrev, Alexander; Mace, Gregory N.; Massey, Philip; Roe, Henry G.; Prato, Lisa A.

2017-01-01

The Lowell Observatory Discovery Channel Telescope (DCT) has been in full science operation for 2 years (2015 and 2016). Five instruments have been commissioned during that period, and two additional instruments are planned for 2017. These include:+ Large Monolithic Imager (LMI) - a CCD imager (12.6 arcmin FoV)+ DeVeny - a general purpose optical spectrograph (2 arcmin slit length, 10 grating choices)+ NIHTS - a low resolution (R=160) YJHK spectrograph (1.3 arcmin slit)+ DSSI - a two-channel optical speckle imager (5 arcsec FoV)+ IGRINS - a high resolution (45,000) HK spectrograph, on loan from the University of Texas.In the upcoming year, instruments will be delivered from the University of Maryland (RIMAS - a YJHK imager/spectrograph) and from Yale University (EXPRES - a very high resolution stabilized optical echelle for PRV).Each of these instruments will be described, along with their primary science goals.

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.

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.

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.

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.

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.

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.

System engineering at the MEGARA project

NASA Astrophysics Data System (ADS)

Pérez-Calpena, A.; García-Vargas, María. Luisa; Gil de Paz, A.; Gallego Maestro, J.; Carrasco Licea, E.; Sánchez Moreno, F.; Iglesias-Páramo, J.

2014-08-01

MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía) is a facility instrument of the 10.4m GTC (La Palma, Spain) working at optical wavelengths that provides both Integral-Field Unit (IFU) and Multi- Object Spectrograph (MOS) capabilities at resolutions in the range R=6,000-20,000. The MEGARA focal plane subsystems are located at one of the GTC focal stations, while the MEGARA refractive VPH based spectrograph is located at one of the Nasmyth platforms. The fiber bundles conduct the light from the focal plane subsystems to the pseudo-slits at the entrance of the spectrograph. The project is an initiative led by Universidad Complutense de Madrid (Spain) in collaboration with INAOE (Mexico), IAA-CSIC (Spain) and Universidad Politécnica de Madrid (Spain) and is developed under contract with GRANTECAN. The project is carried out by a multidisciplinary and geographically distributed team, which includes the in-kind contributions of the project partners and personnel from several private companies. The MEGARA system-engineering plan has been tailored to the project and is being applied to ensure the technical control of the project in order to finally meet the science high-level requirements and GTC constrains.

Simulating observations with HARMONI: the integral field spectrograph for the European Extremely Large Telescope

NASA Astrophysics Data System (ADS)

Zieleniewski, Simon; Thatte, Niranjan; Kendrew, Sarah; Houghton, Ryan; Tecza, Matthias; Clarke, Fraser; Fusco, Thierry; Swinbank, Mark

2014-07-01

With the next generation of extremely large telescopes commencing construction, there is an urgent need for detailed quantitative predictions of the scientific observations that these new telescopes will enable. Most of these new telescopes will have adaptive optics fully integrated with the telescope itself, allowing unprecedented spatial resolution combined with enormous sensitivity. However, the adaptive optics point spread function will be strongly wavelength dependent, requiring detailed simulations that accurately model these variations. We have developed a simulation pipeline for the HARMONI integral field spectrograph, a first light instrument for the European Extremely Large Telescope. The simulator takes high-resolution input data-cubes of astrophysical objects and processes them with accurate atmospheric, telescope and instrumental effects, to produce mock observed cubes for chosen observing parameters. The output cubes represent the result of a perfect data reduc- tion process, enabling a detailed analysis and comparison between input and output, showcasing HARMONI's capabilities. The simulations utilise a detailed knowledge of the telescope's wavelength dependent adaptive op- tics point spread function. We discuss the simulation pipeline and present an early example of the pipeline functionality for simulating observations of high redshift galaxies.

Development of the fibre positioning unit of MOONS

NASA Astrophysics Data System (ADS)

Montgomery, David; Atkinson, David; Beard, Stephen; Cochrane, William; Drass, Holger; Guinouard, Isabelle; Lee, David; Taylor, William; Rees, Phil; Watson, Steve

2016-08-01

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. This can be configured to produce spectra for chosen targets and have close proximity sky subtraction if required. The system will have both a medium resolution (R 4000-6000) mode and a high resolution (R 20000) mode. The fibre positioning units are used to position each fibre independently in order to pick off each sub field of 1.0" within a circular patrol area of 85" on sky (50mm physical diameter). The nominal physical separation between FPUs is 25mm allowing a 100% overlap in coverage between adjacent units. The design of the fibre positioning units allows parallel and rapid reconfiguration between observations. The kinematic geometry is such that pupil alignment is maintained over the patrol area. This paper presents the design of the Fibre Positioning Units at the preliminary design review and the results of verification testing of the advanced prototypes.

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.

Geostationary Spectrograph (GeoSpec) for Earth and Atmospheric Science Applications

NASA Technical Reports Server (NTRS)

Janz, Scott J.

2003-01-01

GeoSpec will support several possible future mission concepts in the Atmospheric Sciences and in Land and Ocean Sciences by measurement of both chemically linked atmospheric trace gas concentrations and profiles of important molecules such as OS, N02, CH20 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 we will describe is a dual spectrograph covering the WMS wavelength region of 310- 481 nm and the VIS/NIR wavelength region of 500-900 nm. A third channel in the short- wave infrared (SWIR) region between 2.2 p and 2.4 pn for total column measurements of CO, CH4, and N20 will also be described. The goal is to design a system capable of making moderate spatial resolution (750 meters at nadir) hyperspectral measurements (0.2 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. Technological advances in the design and fabrication of convex holographic gratings and large format, high dynamic range PIN/CMOS detectors at the focal plane will be exploited. By simply changing the focal length of the front-end telescope GeoSpec can accommodate different orbital altitudes, including low Earth orbit, the Sun-side Lagrangian point L1, and/or different spatial resolutions.

The ICE spectrograph for PEPSI at the LBT: preliminary optical design

NASA Astrophysics Data System (ADS)

Pallavicini, Roberto; Zerbi, Filippo M.; Spano, Paolo; Conconi, Paolo; Mazzoleni, Ruben; Molinari, Emilio; Strassmeier, Klaus G.

2003-03-01

We present a preliminary design study for a high-resolution echelle spectrograph (ICE) to be used with the spectropolarimeter PEPSI under development at the LBT. In order to meet the scientific requirements and take full advantage of the peculiarities of the LBT (i.e. the binocular nature and the adaptive optics capabilities), we have designed a fiber-fed bench mounted instrument for both high resolution (R ≍ 100,000; non-AO polarimetric and integral light modes) and ultra-high resolution (R ≍ 300,000; AO integral light mode). In both cases, 4 spectra per order (two for each primary mirror) shall be accomodated in a 2-dimensional cross dispersed echelle format. In order to obtain a resolution-slit product of ≍ 100,000 as required by the science case, we have considered two alternative designs, one with two R4 echelles in series and the other with a sigle R4 echelle and fiber slicing. A white-pupil design, VPH cross-dispersers and two cameras of different focal length for the AO and non-AO modes are adopted in both cases. It is concluded that the single-echelle fiber-slicer solution has to be preferred in terms of performances, complexity and cost. It can be implemented at the LBT in two phases, with the long-camera AO mode added in a second phase depending on the availability of funds and the time-scale for implementation of the AO system.

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.

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.

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

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.

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.

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

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.

Compact high-resolution spectrographs for large and extremely large telescopes: using the diffraction limit

NASA Astrophysics Data System (ADS)

Robertson, J. Gordon; Bland-Hawthorn, Joss

2012-09-01

As telescopes get larger, the size of a seeing-limited spectrograph for a given resolving power becomes larger also, and for ELTs the size will be so great that high resolution instruments of simple design will be infeasible. Solutions include adaptive optics (but not providing full correction for short wavelengths) or image slicers (which give feasible but still large instruments). Here we develop the solution proposed by Bland-Hawthorn and Horton: the use of diffraction-limited spectrographs which are compact even for high resolving power. Their use is made possible by the photonic lantern, which splits a multi-mode optical fiber into a number of single-mode fibers. We describe preliminary designs for such spectrographs, at a resolving power of R ~ 50,000. While they are small and use relatively simple optics, the challenges are to accommodate the longest possible fiber slit (hence maximum number of single-mode fibers in one spectrograph) and to accept the beam from each fiber at a focal ratio considerably faster than for most spectrograph collimators, while maintaining diffraction-limited imaging quality. It is possible to obtain excellent performance despite these challenges. We also briefly consider the number of such spectrographs required, which can be reduced by full or partial adaptive optics correction, and/or moving towards longer wavelengths.

VizieR Online Data Catalog: Spectroscopy of the foreground population in Orion A (Fang+, 2017)

NASA Astrophysics Data System (ADS)

Fang, M.; Kim, J. S.; Pascucci, I.; Apai, D.; Zhang, L.; Sicilia-Aguilar, A.; Alonso-Martinez, M.; Eiroa, C.; Wang, H.

2018-05-01

We performed a low-resolution spectroscopic survey of the stellar population in NGC 1980 with the Hectospec multi-object spectrograph, capable of taking a maximum of 300 spectra simultaneously. We used the 270 groove/mm grating and obtained spectra in the 3700-9000Å range with a spectral resolution of ~5Å. The data were taken in 2016 February. In Table 4, we list the young stars with X-Shooter spectra. These sources are mainly from the {eta} Cha cluster, the TW Hydra Association, the Lupus star-forming region, the σ Ori cluster, and the Cha I star-forming region. We extract the spectra of these sources from the X-Shooter phase III data archive. (3 data files).

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.

Optical design of a versatile FIRST high-resolution near-IR spectrograph

NASA Astrophysics Data System (ADS)

Zhao, Bo; Ge, Jian

2012-09-01

We report the update optical design of a versatile FIRST high resolution near IR spectrograph, which is called Florida IR Silicon immersion grating spectromeTer (FIRST). This spectrograph uses cross-dispersed echelle design with white pupils and also takes advantage of the image slicing to increase the spectra resolution, while maintaining the instrument throughput. It is an extremely high dispersion R1.4 (blazed angle of 54.74°) silicon immersion grating with a 49 mm diameter pupil is used as the main disperser at 1.4μm -1.8μm to produce R=72,000 while an R4 echelle with the same pupil diameter produces R=60,000 at 0.8μm -1.35μm. Two cryogenic Volume Phase Holographic (VPH) gratings are used as cross-dispersers to allow simultaneous wavelength coverage of 0.8μm -1.8μm. The butterfly mirrors and dichroic beamsplitters make a compact folding system to record these two wavelength bands with a 2kx2k H2RG array in a single exposure. By inserting a mirror before the grating disperser (the SIG and the echelle), this spectrograph becomes a very efficient integral field 3-D imaging spectrograph with R=2,000-4,000 at 0.8μm-1.8μm by coupling a 10x10 telescope fiber bundle with the spectrograph. Details about the optical design and performance are reported.

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.

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.

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.

Scientific Design of a High Contrast Integral Field Spectrograph for the Subaru Telescope

NASA Technical Reports Server (NTRS)

McElwain, Michael W.

2012-01-01

Ground based telescopes equipped with adaptive optics systems and specialized science cameras are now capable of directly detecting extrasolar planets. We present the scientific design for a high contrast integral field spectrograph for the Subaru Telescope. This lenslet based integral field spectrograph will be implemented into the new extreme adaptive optics system at Subaru, called SCExAO.

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.

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.

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.

X-ray optics for WHIMex: the Warm Hot Intergalactic Medium Explorer

NASA Astrophysics Data System (ADS)

Cash, W.; McEntaffer, R.; Zhang, W.; Casement, S.; Lillie, C.; Schattenburg, M.; Bautz, M.; Holland, A.; Tsunemi, H.; O'Dell, S.

2011-09-01

The x-ray astronomy community has never flown a celestial source spectrograph that can resolve natural line widths in absorption the way the ultraviolet community did with OAO-3 Copernicus back in 1972. Yet there is important science to be mined there, and right now, the large flagship missions like the International X-ray Observatory are not progressing toward launch. WHIMEx is an Explorer concept proposed earlier this year to open up that science regime in the next few years. The concept features 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 and capabilities for the WHIMEx mission. Its prime science goal is detecting high temperature oxygen in the Intergalactic Medium, but it has a broad range of science potential cutting across all of x-ray astronomy and should give us a new window on the Universe.

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.

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.

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.

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.

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

Suvorov, Alexey; Cai, Yong Q.

A concept of an inelastic x-ray scattering (IXS) spectrograph with an imaging analyzer was proposed recently and discussed in a number of publications (see e.g. Ref.1). The imaging analyzer as proposed combines x-ray lenses with highly dispersive crystal optics. It allows conversion of the x-ray energy spectrum into a spatial image with very high energy resolution. However, the presented theoretical analysis of the spectrograph did not take into account details of the scattered radiation source, i.e. sample, and its impact on the spectrograph performance. Using numerical simulations we investigated the influence of the finite sample thickness, the scattering angle andmore » the incident energy detuning on the analyzer image and the ultimate resolution.« less

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).

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.

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.

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.

Instrument Design of the Large Aperture Solar UV Visible and IR Observing Telescope (SUVIT) for the SOLAR-C Mission

NASA Astrophysics Data System (ADS)

Suematsu, Y.; Katsukawa, Y.; Shimizu, T.; Ichimoto, K.; Takeyama, N.

2012-12-01

We present an instrumental design of one major solar observation payload planned for the SOLAR-C mission: the Solar Ultra-violet Visible and near IR observing Telescope (SUVIT). The SUVIT is designed to provide high-angular-resolution investigation of the lower solar atmosphere, from the photosphere to the uppermost chromosphere, with enhanced spectroscopic and spectro-polarimetric capability in wide wavelength regions from 280 nm (Mg II h&k lines) to 1100 nm (He I 1083 nm line) with 1.5 m class aperture and filtergraphic and spectrographic instruments.

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.

Uranus' cloud structure and scattering particle properties from IRTF SpeX observations

NASA Astrophysics Data System (ADS)

Tice, D. S.; Irwin, P. G. J.; Fletcher, L. N.; Teanby, N. A.; Orton, G. S.; Davis, G. R.

2011-10-01

Observations of Uranus were made in August 2009 with the SpeX spectrograph at the NASA Infrared Telescope Facility (IRTF). Analysed spectra range from 0.8 to 1.8 μm at a spatial resolution of 0.5" and a spectral resolution of R = 1,200. Spectra from 0.818 to 0.834 μm, a region characterised by both strong hydrogen quadrupole and methane absorptions are considered to determine methane content. Evidence indicates that methane abundance varies with latitude. NEMESIS, an optimal estimation retrieval code with full-scattering capability, is employed to analyse the full range of data. Cloud and haze properties in the upper troposphere and stratosphere are characterised, and are consistent with other current literature. New information on single scattering albedos and particle size distributions are inferred.

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)

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.

Instrumentation progress at the Giant Magellan Telescope project

NASA Astrophysics Data System (ADS)

Jacoby, George H.; Bernstein, R.; Bouchez, A.; Colless, M.; Crane, Jeff; DePoy, D.; Espeland, B.; Hare, Tyson; Jaffe, D.; Lawrence, J.; Marshall, J.; McGregor, P.; Shectman, Stephen; Sharp, R.; Szentgyorgyi, A.; Uomoto, Alan; Walls, B.

2016-08-01

Instrument development for the 24m Giant Magellan Telescope (GMT) is described: current activities, progress, status, and schedule. One instrument team has completed its preliminary design and is currently beginning its final design (GCLEF, an optical 350-950 nm, high-resolution and precision radial velocity echelle spectrograph). A second instrument team is in its conceptual design phase (GMACS, an optical 350-950 nm, medium resolution, 6-10 arcmin field, multi-object spectrograph). A third instrument team is midway through its preliminary design phase (GMTIFS, a near-IR YJHK diffraction-limited imager/integral-field-spectrograph), focused on risk reduction prototyping and design optimization. A fourth instrument team is currently fabricating the 5 silicon immersion gratings needed to begin its preliminary design phase (GMTNIRS, a simultaneous JHKLM high-resolution, AO-fed, echelle spectrograph). And, another instrument team is focusing on technical development and prototyping (MANIFEST, a facility robotic, multifiber feed, with a 20 arcmin field of view). In addition, a medium-field (6 arcmin, 0.06 arcsec/pix) optical imager will support telescope and AO commissioning activities, and will excel at narrow-band imaging. In the spirit of advancing synergies with other groups, the challenges of running an ELT instrument program and opportunities for cross-ELT collaborations are discussed.

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.

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.

First light of the CHARIS high-contrast integral-field spectrograph

NASA Astrophysics Data System (ADS)

Groff, Tyler; Chilcote, Jeffrey; Brandt, Timothy; Kasdin, N. Jeremy; Galvin, Michael; Loomis, Craig; Rizzo, Maxime; Knapp, Gillian; Guyon, Olivier; Jovanovic, Nemanja; Lozi, Julien; Currie, Thayne; Takato, Naruhisa; Hayashi, Masahiko

2017-09-01

One of the leading direct Imaging techniques, particularly in ground-based imaging, uses a coronagraphic system and integral field spectrograph (IFS). The Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) is an IFS that has been built for the Subaru telescope. CHARIS has been delivered to the observatory and now sits behind the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system. CHARIS has `high' and `low' resolution operating modes. The high-resolution mode is used to characterize targets in J, H, and K bands at R70. The low-resolution prism is meant for discovery and spans J+H+K bands (1.15-2.37 microns) with a spectral resolution of R18. This discovery mode has already proven better than 15-sigma detections of HR8799c,d,e when combining ADI+SDI. Using SDI alone, planets c and d have been detected in a single 24 second image. The CHARIS team is optimizing instrument performance and refining ADI+SDI recombination to maximize our contrast detection limit. In addition to the new observing modes, CHARIS has demonstrated a design with high robustness to spectral crosstalk. CHARIS has completed commissioning and is open for science observations.

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).

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.

A High-Speed Spectroscopy System for Observing Lightning and Transient Luminous Events

NASA Astrophysics Data System (ADS)

Boggs, L.; Liu, N.; Austin, M.; Aguirre, F.; Tilles, J.; Nag, A.; Lazarus, S. M.; Rassoul, H.

2017-12-01

Here we present a high-speed spectroscopy system that can be used to record atmospheric electrical discharges, including lightning and transient luminous events. The system consists of a Phantom V1210 high-speed camera, a Volume Phase Holographic (VPH) grism, an optional optical slit, and lenses. The spectrograph has the capability to record videos at speeds of 200,000 frames per second and has an effective wavelength band of 550-775 nm for the first order spectra. When the slit is used, the system has a spectral resolution of about 0.25 nm per pixel. We have constructed a durable enclosure made of heavy duty aluminum to house the high-speed spectrograph. It has two fans for continuous air flow and a removable tray to mount the spectrograph components. In addition, a Watec video camera (30 frames per second) is attached to the top of the enclosure to provide a scene view. A heavy duty Pelco pan/tilt motor is used to position the enclosure and can be controlled remotely through a Rasperry Pi computer. An observation campaign has been conducted during the summer and fall of 2017 at the Florida Institute of Technology. Several close cloud-to-ground discharges were recorded at 57,000 frames per second. The spectrum of a downward stepped negative leader and a positive cloud-to-ground return stroke will be reported on.

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.

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.

NRES: The Network of Robotic Echelle Spectrographs

NASA Astrophysics Data System (ADS)

Siverd, Robert; Brown, Tim; Henderson, Todd; Hygelund, John; Barnes, Stuart; de Vera, Jon; Eastman, Jason; Kirby, Annie; Smith, Cary; Taylor, Brook; Tufts, Joseph; van Eyken, Julian

2018-01-01

Las Cumbres Observatory (LCO) is building the Network of Robotic Echelle Spectrographs (NRES), which will consist of four (up to six in the future) identical, optical (390 - 860 nm) high-precision spectrographs, each fiber-fed simultaneously by up to two 1-meter telescopes and a Thorium-Argon calibration source. We plan to install one at up to 6 observatory sites in the Northern and Southern hemispheres, creating a single, globally-distributed, autonomous spectrograph facility using up to ten 1-m telescopes. Simulations suggest we will achieve long-term radial velocity precision of 3 m/s in less than an hour for stars brighter than V = 11 or 12 once the system reaches full capability. Acting in concert, these four spectrographs will provide a new, unique facility for stellar characterization and precise radial velocities.Following a few months of on-sky evaluation at our BPL test facility, the first spectrograph unit was shipped to CTIO in late 2016 and installed in March 2017. After several more months of additional testing and commissioning, regular science operations began with this node in September 2017. The second NRES spectrograph was installed at McDonald Observatory in September 2017 and released to the network after its own brief commissioning period, extending spectroscopic capability to the Northern hemisphere. The third NRES spectrograph was installed at SAAO in November 2017 and released to our science community just before year's end. The fourth NRES unit shipped in October and is currently en route to Wise Observatory in Israel with an expected release to the science community in early 2018.We will briefly overview the LCO telescope network, the NRES spectrograph design, the advantages it provides, and development challenges we encountered along the way. We will further discuss real-world performance from our first three units, initial science results, and the ongoing software development effort needed to automate such a facility for a wide array of science cases.

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 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.

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.

PEPSI: the Potsdam Echelle Polarimetric and Spectroscopic Instrument for the LBT

NASA Astrophysics Data System (ADS)

Strassmeier, K. G.; Woche, M.; Ilyin, I.; Popow, E.; Bauer, S.-M.; Dionies, F.; Fechner, T.; Weber, M.; Hofmann, A.; Storm, J.; Materne, R.; Bittner, W.; Bartus, J.; Granzer, T.; Denker, C.; Carroll, T.; Kopf, M.; DiVarano, I.; Beckert, E.; Lesser, M.

2008-07-01

We present the status of PEPSI, the bench-mounted fibre-fed and stabilized "Potsdam Echelle Polarimetric and Spectroscopic Instrument" for the 2×8.4m Large Binocular Telescope in southern Arizona. PEPSI is under construction at AIP and is scheduled for first light in 2009/10. Its ultra-high-resolution mode will deliver an unprecedented spectral resolution of approximately R=310,000 at high efficiency throughout the entire optical/red wavelength range 390-1050nm without the need for adaptive optics. Besides its polarimetric Stokes IQUV mode, the capability to cover the entire optical range in three exposures at resolutions of 40,000, 130,000 and 310,000 will surpass all existing facilities in terms of light-gathering-power times spectral-coverage product. A solar feed will make use of the spectrograph also during day time. As such, we hope that PEPSI will be the most powerful spectrometer of its kind for the years to come.

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.

PUCHEROS: a cost-effective solution for high-resolution spectroscopy with small telescopes

NASA Astrophysics Data System (ADS)

Vanzi, L.; Chacon, J.; Helminiak, K. G.; Baffico, M.; Rivinius, T.; Štefl, S.; Baade, D.; Avila, G.; Guirao, C.

2012-08-01

We present PUCHEROS, the high-resolution echelle spectrograph, developed at the Center of Astro-Engineering of Pontificia Universidad Catolica de Chile to provide an effective tool for research and teaching of astronomy. The instrument is fed by a single-channel optical fibre and it covers the visible range from 390 to 730 nm in one shot, reaching a spectral resolution of about 20 000. In the era of extremely large telescopes our instrument aims to exploit the capabilities offered by small telescopes in a cost-effective way, covering the observing needs of a community of astronomers, in Chile and elsewhere, which do not necessarily need large collecting areas for their research. In particular the instrument is well suited for long-term spectroscopic monitoring of bright variable and transient targets down to a V magnitude of about 10. We describe the instrument and present a number of text case examples of observations obtained during commissioning and early science.

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).

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.

2010-06-01

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a joint U.S./German Project to develop and operate a 2.5-meter infrared airborne telescope in a Boeing 747-SP that flies in the stratosphere at altitudes as high as 45,000 feet and is capable of observations from 0.3 microns to 1.6 mm with an average transmission of greater than 80 percent. SOFIA will be staged out of the NASA Dryden Flight Research Center aircraft operations facility at Palmdale, CA and the SOFIA Science Mission Operations Center (SSMOC) will be located at NASA Ames Research Center, Moffett Field, CA. Open door test flights began in December of 2009. First science flights will begin in 2010, and the number of flights will ramp up annually with a flight rate of over 100 eight to ten hour flights per year expected by 2014. The observatory is expected to operate until the mid 2030's. We review the status of the SOFIA facility and its initial complement of eight focal plane instruments that include 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 molecular and atomic gas lines at km/s resolution.

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.

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.

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.

Conceptual Design of the Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) for the Subaru Telescope

NASA Technical Reports Server (NTRS)

Peters, Mary Anne; Groff, Tyler; Kasdin, N. Jeremy; McElwain, Michael W.; Galvin, Michael; Carr, Michael A.; Lupton, Robert; Gunn, James E.; Knapp, Gillian; Gong, Qian;

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.

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.

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.

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.

Supercontinuum ultra-high resolution line-field OCT; experimental spectrograph comparison and comparison with current clinical OCT systems by the imaging of a human cornea

NASA Astrophysics Data System (ADS)

Lawman, Samuel; Romano, Vito; Madden, Peter W.; Mason, Sharon; Williams, Bryan M.; Zheng, Yalin; Shen, Yao-Chun

2018-03-01

Ultra high axial resolution (UHR) was demonstrated early in the development of optical coherence tomography (OCT), but has not yet reached clinical practice. We present the combination of supercontinuum light source and line field (LF-) OCT as a technical and economical route to get UHR-OCT into clinic and other OCT application areas. We directly compare images of a human donor cornea taken with low and high resolution current generation clinical OCT systems with UHR-LF-OCT. These images highlight the massive information increase of UHR-OCT. Application to pharmaceutical pellets, and the functionality and imaging performance of different imaging spectrograph choices for LF- OCT are also demonstrated.

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).

High precision radial velocities with GIANO spectra

NASA Astrophysics Data System (ADS)

Carleo, I.; Sanna, N.; Gratton, R.; Benatti, S.; Bonavita, M.; Oliva, E.; Origlia, L.; Desidera, S.; Claudi, R.; Sissa, E.

2016-06-01

Radial velocities (RV) measured from near-infrared (NIR) spectra are a potentially excellent tool to search for extrasolar planets around cool or active stars. High resolution infrared (IR) spectrographs now available are reaching the high precision of visible instruments, with a constant improvement over time. GIANO is an infrared echelle spectrograph at the Telescopio Nazionale Galileo (TNG) and it is a powerful tool to provide high resolution spectra for accurate RV measurements of exoplanets and for chemical and dynamical studies of stellar or extragalactic objects. No other high spectral resolution IR instrument has GIANO's capability to cover the entire NIR wavelength range (0.95-2.45 μm) in a single exposure. In this paper we describe the ensemble of procedures that we have developed to measure high precision RVs on GIANO spectra acquired during the Science Verification (SV) run, using the telluric lines as wavelength reference. We used the Cross Correlation Function (CCF) method to determine the velocity for both the star and the telluric lines. For this purpose, we constructed two suitable digital masks that include about 2000 stellar lines, and a similar number of telluric lines. The method is applied to various targets with different spectral type, from K2V to M8 stars. We reached different precisions mainly depending on the H-magnitudes: for H ˜ 5 we obtain an rms scatter of ˜ 10 m s-1, while for H ˜ 9 the standard deviation increases to ˜ 50 ÷ 80 m s-1. The corresponding theoretical error expectations are ˜ 4 m s-1 and 30 m s-1, respectively. Finally we provide the RVs measured with our procedure for the targets observed during GIANO Science Verification.

Slitless Spectroscopy

NASA Astrophysics Data System (ADS)

Davila, J. M.; O'Neill, J. F.

2013-12-01

Spectrographs provide a unique window into plasma parameters in the solar atmosphere. In fact spectrographs provide the most accurate measurements of plasma parameters such as density, temperature, and flow speed. However, traditionally spectrographic instruments have suffered from the inability to cover large spatial regions of the Sun quickly. To cover an active region sized spatial region, the slit must be rastered over the area of interest with an exposure taken at each pointing location. Because of this long cycle time, the spectra of dynamic events like flares, CME initiations, or transient brightening are obtained only rarely. And even if spectra are obtained they are either taken over an extremely small spatial region, or the spectra are not co-temporal across the raster. Either of these complicates the interpretation of the spectral raster results. Imagers are able to provide high time and spatial resolution images of the full Sun but with limited spectral resolution. The telescopes onboard the Solar Dynamics Observatory (SDO) normally take a full disk solar image every 10 seconds with roughly 1 arcsec spatial resolution. However the spectral resolution of the multilayer imagers on SDO is of order 100 times less than a typical spectrograph. Because of this it is difficult to interpret multilayer imaging data to accurately obtain plasma parameters like temperature and density from these data, and there is no direct measure of plasma flow velocity. SERTS and EIS partially addressed this problem by using a wide slit to produce monochromatic images with limited FOV to limit overlapping. However dispersion within the wide slit image remained a problem which prevented the determination of intensity, Doppler shift, and line width in the wide slit. Kankelborg and Thomas introduced the idea of using multiple images -1, 0, and +1 spectral orders of a single emission line. This scheme provided three independent images to measure the three spectral line parameters in each pixel with the Multi-Order Solar EUV Spectrograph (MOSES) instrument. We suggest a reconstruction approach based on tomographic methods with regularization. Preliminary results show that the typical Doppler shift and line width error introduced by the reconstruction method is of order a few km/s at 300 A. This is on the order of the error obtained in narrow slit spectrographs but with data obtained over a two-dimensional field of view.

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 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.

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: Photmetry and spectroscopy of PMS stars in NGC 2264 (Lim+, 2016)

NASA Astrophysics Data System (ADS)

Lim, B.; Sung, H.; Kim, J. S.; Bessell, M. S.; Hwang, N.; Park, B.-G.

2018-04-01

Queue scheduled observations were carried out on 2015 April 1 and November 24 with the multi-object high resolution echelle spectrograph Hectochelle attached to the 6.5m telescope of the MMT observatory. The resolving power of the spectrograph (R~34,000) is high enough to detect the LiI λ6708 resonance doublet with little blending from adjacent metallic lines. The multi-object capability allowed us to simultaneously obtain 240 target and sky spectra in a single observation. The OB 26 filter transmits the wavelength range 6530-6715Å, and therefore the useful spectral features Hα λ6563 and HeI λ6678 could also be observed along with the LiI λ6708 line. The spectra of a total of 134 PMS stars were taken in two sets of exposure times -8 minutes x3 for bright stars (V<13.6mag) and 30 minutes x3 for fainter stars. Offset sky spectra were also obtained to correct for the contributions of locally variable nebula emission lines to the spectra of the faint stars. Calibration frames, such as dome flat and comparison spectra, were also acquired, just before and after the target exposure. (1 data file).

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.

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.

Prospects for Measuring Supermassive Black Hole Masses with Future Extremely Large Telescopes

NASA Astrophysics Data System (ADS)

Do, Tuan; Wright, S. A.; Barton, E. J.; Barth, A. J.; Simard, L.; Larkin, J. E.; Moore, A.

2013-01-01

The next generation of giant-segmented mirror telescopes (> 20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope (TMT) and the adaptive optics assisted integral-field spectrograph IRIS. These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument, to determine the expected signal-to-noise of a range of possible targets spanning intermediate mass black holes of ~10^4 M⊙ to the most massive black holes known today of >10^10 M⊙. We find that future integral-field spectrographs will be able to observe Milky Way-mass black holes out the distance of the Virgo cluster, and will allow us to observe many more brightest-cluster galaxies where the most massive black holes are thought to reside. We also evaluate how well the kinematic moments of the velocity distributions can be constrained at different spectral resolutions and plate scales. We find that a spectral resolution of ~8000 will be necessary to measure the masses of IMBHs. We find by using the SDSS DR7 catalog of galaxies that over 4000 massive black holes will be observable at distances between 0.005 < z < 0.3 with the estimated sensitivity and angular resolution of TMT. These observations will provide the most accurate dynamical mass measurements of black holes to enable the study of their demography, address the origin of the M_bh-σ and M_bh - L relationships, and the origins and evolution of black holes through cosmic time.

Web-based multi-channel analyzer

DOEpatents

Gritzo, Russ E.

2003-12-23

The present invention provides an improved multi-channel analyzer designed to conveniently gather, process, and distribute spectrographic pulse data. The multi-channel analyzer may operate on a computer system having memory, a processor, and the capability to connect to a network and to receive digitized spectrographic pulses. The multi-channel analyzer may have a software module integrated with a general-purpose operating system that may receive digitized spectrographic pulses for at least 10,000 pulses per second. The multi-channel analyzer may further have a user-level software module that may receive user-specified controls dictating the operation of the multi-channel analyzer, making the multi-channel analyzer customizable by the end-user. The user-level software may further categorize and conveniently distribute spectrographic pulse data employing non-proprietary, standard communication protocols and formats.

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.

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;

The CHARIS High-Contrast Integral-Field Spectrograph

NASA Technical Reports Server (NTRS)

Groff, Tyler D.; Chilcote, Jeffrey; Brandt, Timothy; Kasdin, N. Jeremy; Galvin, Michael; Loomis, Craig; Rizzo, Maxime; Knapp, Gillian; Guyon, Olivier; Jovanovic, Nemanja;

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.

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.

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

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.

The optical design of GMOX: a next-generation instrument concept for Gemini

NASA Astrophysics Data System (ADS)

Barkhouser, Robert; Robberto, Massimo; Smee, Stephen A.; Ninkov, Zoran; Gennaro, Mario; Heckman, Timothy

2016-08-01

We present the optical design of GMOX, the Gemini Multi-Object eXtra-wide-band spectrograph. GMOX was selected as part of the Gemini Instrument Feasibility Study to develop capabilities and requirements for the next facility instrument (Gen4#3) for the observatory. We envision GMOX covering the entire optical/near-IR wavelength range accessible from the ground, from 3500 Å in the U band up to 2.4 μm in the K band, with nominal resolving power R≃5,000. To maximize efficiency, the bandpass is split into three spectrograph arms - blue, red, and near-infrared - with the near-infrared arm further split into three channels covering the Y+J, H, and K bands. At the heart of each arm is a Digital Micromirror Device (DMD) serving as a programmable slit array. This technology will enable GMOX to simultaneously acquire hundreds of spectra of faint sources in crowded fields with unparalleled spatial resolution, optimally adapting to both seeing-limited and diffraction limited conditions provided by ALTAIR and GeMS at Gemini North and South, respectively. Fed by GeMS at f/33, GMOX can synthesize slits as small as 40 mas (corresponding to a single HST/WFC3 CCD pixel) over its entire 85"x45" field of view. With either ALTAIR or the native telescope focal ratio of f/16, both the slit and field sizes double. In this paper we discuss the conceptual optical design of GMOX including, for each arm: the pre-slit optics, DMD slit array, off-axis Schmidt collimator, VPH grating, and refractive spectrograph and slit-viewing cameras.

GNOSIS: The First Fiber Bragg Grating-based OH Suppression Unit

NASA Astrophysics Data System (ADS)

Trinh, Christopher; Ellis, S. C.; Bland-Hawthorn, J.; Lawrence, J. S.; Horton, A. J.; Leon-Saval, S. G.; Shortridge, K.; Bryant, J.; Case, S.; Colless, M.; Couch, W.; Freeman, K. C.; Löhmannsröben, H.; Gers, L.; Glazebrook, K.; Haynes, R.; Lee, S.; O'Byrne, J.; Miziarski, S.; Roth, M. M.; Schmidt, B.; Tinney, C. G.; Zheng, J.

2013-01-01

The sky background is over 1000 times brighter in the near-infrared (NIR) than in the visible placing severe limitations on our ability to study the redshifted light from the distant objects formed in the early Universe from the ground. It is well-known that 98% of the NIR background comes from the forest of bright and highly variable emission lines of atmospheric hydroxyl (OH) molecules. Unfortunately, astronomers have been unable to effectively remove this background from their data. We present the first OH suppression unit, GNOSIS, to utilize fiber Bragg gratings (FBGs). Simple FBGs are optical fibers with a periodic refractive index modulation imprinted within the fiber core, which induces a strong reflection in a narrow 0.2 nm) stopband. GNOSIS utilizes “OH suppression fibers” with a complex aperiodic refractive index modulation capable of removing the 103 brightest OH doublets between 1470 and 1700 nm by up 30 dB before dispersion and in a manner purely dependent on wavelength. The OH suppression fibers have high throughput 60%) and over 90% of the H band is available for spectroscopy. OH suppression units like GNOSIS may be utilized with any NIR telescope and spectrograph combination, but we commissioned GNOSIS at the 3.9-meter Anglo-Australian Telescope with the IRIS2 spectrograph for our first demonstration. Commissioning reveals excellent suppression performance. Approximately 78% of the OH lines were suppressed at the target level or greater. GNOSIS reduces the integrated background between 1500 and 1700 nm by a factor of ~ 9 but the signal-to-noise ratio is about the same as standard long-slit IRIS2 observations due to retrofitting to an un-optimized spectrograph. Nevertheless, if paired with a fiber-optimized spectrograph FBG OH suppression technology shows great promise for high sensitivity NIR spectroscopy at moderate to low resolutions from the ground.

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.

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

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.

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.

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.

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.

The GMT-Consortium Large Earth Finder (G-CLEF) : An Optical Echelle Spectrograph for the Giant Magellan Telescope (GMT) with Multi-Object Spectroscopy (MOS) Capability

NASA Astrophysics Data System (ADS)

Szentgyorgyi, Andrew

2017-09-01

"The GMT-Consortium Large Earth Finder (G-CLEF) is an optical band echelle spectrograph that has been selected as the first light instrument for the Giant Magellan Telescope (GMT). G-CLEF is a general purpose, high dispersion instrument that is fiber fed and capable of extremely precise radial velocity (PRV) measurements. G-CLEF will have a novel multi-object spectroscopy (MOS) capability that will be useful for a number of exoplanet science programs. I describe the general properties of G-CLEF and the systems engineering analyses, especially for PRV, that drove the current G-CLEF design. The requirements for calibration of the MOS channel are presented along with several novel approaches for achieving moderate radial velocity precision in the MOS mode."

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.

The Lightcurve Legacy of COS and STIS

NASA Astrophysics Data System (ADS)

Ely, Justin

2014-10-01

The Cosmic Origin Spectrograph {COS} and Space Telescope Imaging Spectrograph {STIS} 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 detector designs, both of these instruments can operate in a mode where each indivudal photon's arrival time is recorded and saved. Though this TIME-TAG 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 the appropriate knowledge and software, the time-resolved spectra can instead be extracted into photometric lightcurves with high temporal and spectral resolution.We propose here to expand our current software tool into a community-ready pipeline and to deliver a collection of high-level science lightcurves for the entire COS and STIS TIME-TAG archives. By providing this tool and data archive to the community we will lower the barrier to time domain research with these two instruments. This will demonstrate to the community not only the potential contained in re-analysis of existing datasets, but also the exquisite time-series capabilities of the instruments available for future cycles. The enabling and demonstration of this so far underutilized technique should be done now. At a time when HST and its UV capabilities are nearing their end, it's vital that all possible avenues for exploration are made readily available to the scientific community.

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).

An Expert System for Classifying Stars on the MK Spectral Classification System

NASA Astrophysics Data System (ADS)

Corbally, Christopher J.; Gray, R. O.

2013-01-01

We will describe an expert computer system designed to classify stellar spectra on the MK Spectral Classification system employing methods similar to those of humans who make direct comparison with the MK classification standards. Like an expert human classifier, MKCLASS first comes up with a rough spectral type, and then refines that type by direct comparison with MK standards drawn from a standards library using spectral criteria appropriate to the spectral class. Certain common spectral-type peculiarities can also be detected by the program. The program is also capable of identifying WD spectra and carbon stars and giving appropriate (but currently approximate) spectral types on the relevant systems. We will show comparisons between spectral types (including luminosity types) performed by MKCLASS and humans. The program currently is capable of competent classifications in the violet-green region, but plans are underway to extend the spectral criteria into the red and near-infrared regions. Two standard libraries with resolutions of 1.8 and 3.6Å are now available, but a higher-resolution standard library, using the new spectrograph on the Vatican Advanced Technology Telescope, is currently under preparation. Once that library is available, MKCLASS and the spectral libraries will be made available to the astronomical community.

LOITA: Lunar Optical/Infrared Telescope Array

NASA Technical Reports Server (NTRS)

1993-01-01

LOITA (Lunar Optical/Infrared Telescope Array) is a lunar-based interferometer composed of 18 alt-azimuth telescopes arranged in a circular geometry. This geometry results in excellent uv coverage and allows baselines up to 5 km long. The angular resolution will be 25 micro-arcsec at 500 nm and the main spectral range of the array will be 200 to 1100 nm. For infrared planet detection, the spectral range may be extended to nearly 10 mu m. The telescope mirrors have a Cassegrain configuration using a 1.75 m diameter primary mirror and a 0.24 m diameter secondary mirror. A three-stage (coarse, intermediate, and fine) optical delay system, controlled by laser metrology, is used to equalize path lengths from different telescopes to within a few wavelengths. All instruments and the fine delay system are located within the instrument room. Upon exiting the fine delay system, all beams enter the beam combiner and are then directed to the various scientific instruments and detectors. The array instrumentation will consist of CCD detectors optimized for both the visible and infrared as well as specially designed cameras and spectrographs. For direct planet detection, a beam combiner employing achromatic nulling interferometry will be used to reduce star light (by several orders of magnitude) while passing the planet light. A single telescope will be capable of autonomous operation. This telescope will be equipped with four instruments: wide field and planetary camera, faint object camera, high resolution spectrograph, and faint object spectrograph. These instruments will be housed beneath the telescope. The array pointing and control system is designed to meet the fine pointing requirement of one micro-arcsec stability and to allow precise tracking of celestial objects for up to 12 days. During the lunar night, the optics and the detectors will be passively cooled to 70-80 K temperature. To maintain a continuous communication with the earth a relay satellite placed at the L4 libration point will be used in conjunction with the Advanced Tracking and Data Relay Satellite System (ATDRSS). Electrical power of about 10 kW will be supplied by a nuclear reactor based on the SP-100 technology. LOITA will be constructed in three phases of six telescopes each. The total mass of the first operational phase is estimated at 58,820 kg. The cost of the fully operational first phase of the observatory is estimated at $8.9 billion. LOITA's primary objectives will be to detect and characterize planets around nearby stars (up to ten parsec away), study physics of collapsed stellar objects, solar/stellar surface features and the processes in nuclear regions of galaxies and quasars. An interferometric array such as LOITA will be capable of achieving resolutions three orders of magnitude greater than Hubble's design goal. LOITA will also be able to maintain higher signal to noise ratios than are currently attainable due to long observation times available on the moon.

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).

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).

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.

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).

The Stratospheric Observatory for Infrared Astronomy (SOFIA)

NASA Astrophysics Data System (ADS)

Gehrz, Robert; Becklin, Eric; Young, Erick; Krabbe, Alfred; Marcum, Pamela; Roellig, Thomas

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a joint U.S./German Project to develop and operate a 2.5-meter infrared airborne telescope in a Boeing 747-SP that flies in the stratosphere at altitudes as high as 45,000 and is capable of observations from 0.3 microns to 1.6 mm with an average transmission greater than 80 percent. SOFIA will be staged out of the NASA Dryden Flight Research Center aircraft operations facility at Palmdale, CA and the SOFIA Science Mission Operations Center (SSMOC) will be located at NASA Ames Research Center, Moffett Field, CA. First science flights will begin in 2010, and the number of flights will ramp up annually with a flight rate of over 100 8 to 10 hour flights per year expected by 2014. The observatory is expected to operate until the mid 2030's. SOFIA will initially fly with eight focal plane instruments that include 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 molecular and atomic gas lines at km/s resolution. We describe the SOFIA facility and outline the opportunities for observations by the general scientific community and future instrumentation developments. The operational characteristics of the SOFIA first-generation instruments are summarized and we give several specific examples of the types of scientific studies to which these instruments are expected to make fundamental scientific contributions.

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.

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.

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.

Process analysis of recycled thermoplasts from consumer electronics by laser-induced plasma spectroscopy.

PubMed

Fink, Herbert; Panne, Ulrich; Niessner, Reinhard

2002-09-01

An experimental setup for direct elemental analysis of recycled thermoplasts from consumer electronics by laser-induced plasma spectroscopy (LIPS, or laser-induced breakdown spectroscopy, LIBS) was realized. The combination of a echelle spectrograph, featuring a high resolution with a broad spectral coverage, with multivariate methods, such as PLS, PCR, and variable subset selection via a genetic algorithm, resulted in considerable improvements in selectivity and sensitivity for this complex matrix. With a normalization to carbon as internal standard, the limits of detection were in the ppm range. A preliminary pattern recognition study points to the possibility of polymer recognition via the line-rich echelle spectra. Several experiments at an extruder within a recycling plant demonstrated successfully the capability of LIPS for different kinds of routine on-line process analysis.

Current status of the facility instrumentation suite at the Large Binocular Telescope Observatory

NASA Astrophysics Data System (ADS)

Rothberg, Barry; Kuhn, Olga; Edwards, Michelle L.; Hill, John M.; Thompson, David; Veillet, Christian; Wagner, R. Mark

2016-07-01

The current status of the facility instrumentation for the Large Binocular Telescope (LBT) is reviewed. The LBT encompasses two 8.4 meter primary mirrors on a single mount yielding an effective collecting area of 11.8 meters or 23 meters when interferometrically combined. The three facility instruments at LBT include: 1) the Large Binocular Cameras (LBCs), each with a 23'× 25' field of view (FOV). The blue optimized and red optimized optical wavelength LBCs are mounted at the prime focus of the SX (left) and DX (right) primary mirrors, respectively. Combined, the filter suite of the two LBCs cover 0.3-1.1 μm, including the addition of new medium-band filters centered on TiO (0.78 μm) and CN (0.82 μm) 2) the Multi-Object Double Spectrograph (MODS), two identical optical spectrographs each mounted at the straight through f/15 Gregorian focus of the primary mirrors. The capabilities of MODS-1 and -2 include imaging with Sloan filters (u, g, r, i, and z) and medium resolution (R ˜ 2000) spectroscopy, each with 24 interchangeable masks (multi-object or longslit) over a 6'× 6' FOV. Each MODS is capable of blue (0.32-0.6 μm) and red (0.5-1.05 μm) wavelength only spectroscopy coverage or both can employ a dichroic for 0.32-1.05 μm wavelength coverage (with reduced coverage from 0.56- 0.57 μm) and 3) the two LBT Utility Camera in the Infrared instruments (LUCIs), are each mounted at a bent-front Gregorian f/15 focus of a primary mirror. LUCI-1 and 2 are designed for seeing-limited (4'× 4' FOV) and active optics using thin-shell adaptive secondary mirrors (0.5'× 0.5' FOV) imaging and spectroscopy over the wavelength range of 0.95-2.5 μm and spectroscopic resolutions of 400 <= R <= 11000 (depending on the combination of grating, slits, and cameras used). The spectroscopic capabilities also include 32 interchangeable multi-object or longslit masks which are cryogenically cooled. Currently all facility instruments are in-place at the LBT and, for the first time, have been on-sky for science observations. In Summer 2015 LUCI-1 was refurbished to replace the infrared detector; to install a high-resolution camera to take advantage of the active optics SX secondary; and to install a grating designed primarily for use with high resolution active optics. Thus, like MODS-1 and -2, both LUCIs now have specifications nearly identical to each other. The software interface for both LUCIs have also been replaced, allowing both instruments to be run together from a single interface. With the installation of all facility instruments finally complete we also report on the first science use of "mixed-mode" operations, defined as the combination of different paired instruments with each mirror (i.e. LBC+MODS, LBC+LUCI, LUCI+MODS). Although both primary mirrors reside on a single fixed mount, they are capable of operating as independent entities within a defined "co-pointing" limit. This provides users with the additional capability to independently dither each mirror or center observations on two different sets of spatial coordinates within this limit.

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.

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.

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.

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).

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.

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.

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.

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)

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

Simulated stellar kinematics studies of high-redshift galaxies with the HARMONI Integral Field Spectrograph

NASA Astrophysics Data System (ADS)

Kendrew, S.; Zieleniewski, S.; Houghton, R. C. W.; Thatte, N.; Devriendt, J.; Tecza, M.; Clarke, F.; O'Brien, K.; Häußler, B.

2016-05-01

We present a study into the capabilities of integrated and spatially resolved integral field spectroscopy of galaxies at z = 2-4 with the future HARMONI spectrograph for the European Extremely Large Telescope (E-ELT) using the simulation pipeline, HSIM. We focus particularly on the instrument's capabilities in stellar absorption line integral field spectroscopy, which will allow us to study the stellar kinematics and stellar population characteristics. Such measurements for star-forming and passive galaxies around the peak star formation era will provide a critical insight into the star formation, quenching and mass assembly history of high-z, and thus present-day galaxies. First, we perform a signal-to-noise study for passive galaxies at a range of stellar masses for z = 2-4, assuming different light profiles; for this population, we estimate that integrated stellar absorption line spectroscopy with HARMONI will be limited to galaxies with M* ≳ 1010.7 M⊙. Secondly, we use HSIM to perform a mock observation of a typical star-forming 1010 M⊙ galaxy at z = 3 generated from the high-resolution cosmological simulation NUTFB. We demonstrate that the input stellar kinematics of the simulated galaxy can be accurately recovered from the integrated spectrum in a 15-h observation, using common analysis tools. Whilst spatially resolved spectroscopy is likely to remain out of reach for this particular galaxy, we estimate HARMONI's performance limits in this regime from our findings. This study demonstrates how instrument simulators such as HSIM can be used to quantify instrument performance and study observational biases on kinematics retrieval; and shows the potential of making observational predictions from cosmological simulation output data.

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.

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: 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.

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: 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).

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.

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.

Stratospheric Observatory for Infrared Astronomy (SOFIA): Infrared Sensor Development and Science Capabilities

NASA Astrophysics Data System (ADS)

Nelson, J.; Ruzek, M.

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a unique airborne observatory designed to operate in the lower stratosphere to altitudes as high as 45,000 feet and above 99.8 percent of Earths obscuring atmospheric water vapor. SOFIA's capabilities enable science and observations that will complement and extend past, present and future infrared (IR) telescopes in wavelength range, angular and spectral resolution, and observing flexibility. 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 nearing readiness for for open door flights and demonstration of early science results. Flying in the stratosphere, SOFIA allows observations throughout the infrared and submillimeter region. 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 high resolution. First science flights will begin in early 2010. A great strength of SOFIA is the enormous breadth of its capabilities and the flexibility with which those capabilities can be modified and improved to take advantage of advances in infrared technology. This paper and presentation will highlight the following points: A 2.5-meter effective-diameter optical-quality telescope for diffraction-limited imaging beyond 25 micrometers, giving the sharpest view of the sky provided by any current or developmental IR telescope operating in the 30-60 micrometers region; Wavelength coverage from 0.3 micrometers to 1.6 mm and high resolution spectroscopy (R to 105) at wavelengths between 5 and 150 micrometers; An 8 arcmin FOV allowing use of very large detector arrays; Ready observer access to science instruments which can be serviced in flight and changed between flights; A low-risk ability to incorporate new science-enabling instrument technologies and to create a whole "new" observatory several times during the lifetime of the facility; Opportunity for continuous training of instrumentalists to develop and test the next generation of instrumentation for both suborbital and space applications; Mobility, which allows access to the entire sky and a vastly increased number of stellar occultation events; Unique opportunities for educators and journalists to participate first-hand in exciting astronomical observations. The mid- and far-IR wavelength regions are key to studying the dusty universe. SOFIA science emphasizes four major themes: Star and planet formation; the interstellar medium of the Milky Way; Galaxies and the galactic center; and Planetary science. These capabilities will enable a wide range of science investigations over SOFIA's 20-year operational lifetime. This paper will address SOFIA's nine first-light science instruments, capabilities, and development.

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.

Development of low-noise CCD drive electronics for the world space observatory ultraviolet spectrograph subsystem

NASA Astrophysics Data System (ADS)

Salter, Mike; Clapp, Matthew; King, James; Morse, Tom; Mihalcea, Ionut; Waltham, Nick; Hayes-Thakore, Chris

2016-07-01

World Space Observatory Ultraviolet (WSO-UV) is a major Russian-led international collaboration to develop a large space-borne 1.7 m Ritchey-Chrétien telescope and instrumentation to study the universe at ultraviolet wavelengths between 115 nm and 320 nm, exceeding the current capabilities of ground-based instruments. The WSO Ultraviolet Spectrograph subsystem (WUVS) is led by the Institute of Astronomy of the Russian Academy of Sciences and consists of two high resolution spectrographs covering the Far-UV range of 115-176 nm and the Near-UV range of 174-310 nm, and a long-slit spectrograph covering the wavelength range of 115-305 nm. The custom-designed CCD sensors and cryostat assemblies are being provided by e2v technologies (UK). STFC RAL Space is providing the Camera Electronics Boxes (CEBs) which house the CCD drive electronics for each of the three WUVS channels. This paper presents the results of the detailed characterisation of the WUVS CCD drive electronics. The electronics include a novel high-performance video channel design that utilises Digital Correlated Double Sampling (DCDS) to enable low-noise readout of the CCD at a range of pixel frequencies, including a baseline requirement of less than 3 electrons rms readout noise for the combined CCD and electronics system at a readout rate of 50 kpixels/s. These results illustrate the performance of this new video architecture as part of a wider electronics sub-system that is designed for use in the space environment. In addition to the DCDS video channels, the CEB provides all the bias voltages and clocking waveforms required to operate the CCD and the system is fully programmable via a primary and redundant SpaceWire interface. The development of the CEB electronics design has undergone critical design review and the results presented were obtained using the engineering-grade electronics box. A variety of parameters and tests are included ranging from general system metrics, such as the power and mass, to more detailed analysis of the video performance including noise, linearity, crosstalk, gain stability and transient response.

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).

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.

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.

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).

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.

The Hubble Spectroscopic Legacy Archive

NASA Astrophysics Data System (ADS)

Peeples, Molly S.; Tumlinson, Jason; Fox, Andrew; Aloisi, Alessandra; Ayres, Thomas R.; Danforth, Charles; Fleming, Scott W.; Jenkins, Edward B.; Jedrzejewski, Robert I.; Keeney, Brian A.; Oliveira, Cristina M.

2016-01-01

With no future space ultraviolet instruments currently planned, the data from the UV spectrographs aboard the Hubble Space Telescope have a legacy value beyond their initial science goals. The Hubble Spectroscopic Legacy Archive will provide to the community new science-grade combined spectra for all publicly available data obtained by the Cosmic Origins Spectrograph (COS) and the Space Telescope Imaging Spectrograph (STIS). These data will be packaged into "smart archives" according to target type and scientific themes to facilitate the construction of archival samples for common science uses. A new "quick look" capability will make the data easy for users to quickly access, assess the quality of, and download for archival science starting in Cycle 24, with the first generation of these products for the FUV modes of COS available online via MAST in early 2016.

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.

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.

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.

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.

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.

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.

Identification of Interesting Objects in Large Spectral Surveys Using Highly Parallelized Machine Learning

NASA Astrophysics Data System (ADS)

Škoda, Petr; Palička, Andrej; Koza, Jakub; Shakurova, Ksenia

2017-06-01

The current archives of LAMOST multi-object spectrograph contain millions of fully reduced spectra, from which the automatic pipelines have produced catalogues of many parameters of individual objects, including their approximate spectral classification. This is, however, mostly based on the global shape of the whole spectrum and on integral properties of spectra in given bandpasses, namely presence and equivalent width of prominent spectral lines, while for identification of some interesting object types (e.g. Be stars or quasars) the detailed shape of only a few lines is crucial. Here the machine learning is bringing a new methodology capable of improving the reliability of classification of such objects even in boundary cases. We present results of Spark-based semi-supervised machine learning of LAMOST spectra attempting to automatically identify the single and double-peak emission of Hα line typical for Be and B[e] stars. The labelled sample was obtained from archive of 2m Perek telescope at Ondřejov observatory. A simple physical model of spectrograph resolution was used in domain adaptation to LAMOST training domain. The resulting list of candidates contains dozens of Be stars (some are likely yet unknown), but also a bunch of interesting objects resembling spectra of quasars and even blazars, as well as many instrumental artefacts. The verification of a nature of interesting candidates benefited considerably from cross-matching and visualisation in the Virtual Observatory environment.

Skylab

NASA Image and Video Library

1970-01-01

This 1970 photograph shows the Skylab's Ultraviolet (UV) Spectrograph, an Apollo Telescope Mount instrument. Its telescope, with camera and TV capability, photographed the Sun in selected ultraviolet wavelengths. The spectrograph was used to record the spectrum of UV emissions, such as flares or filaments, from a small individual feature on the solar disc. Real-time TV was used by the crew to monitor the performance of the telescope, transmit to the ground, and record. The exposed films were retrieved by astronaut extravehicular activities. The Marshall Space Flight Center had program management responsibility for the development of the Skylab hardware and experiments.

Skylab

NASA Image and Video Library

1973-01-01

This 1973 chart details Skylab's Ultraviolet (UV) Spectrograph, an Apollo Telescope Mount instrument. Its telescope, with camera and TV capability, photographed the Sun in selected ultraviolet wavelengths. The spectrograph was used to record the spectrum of UV emissions, such as flares or filaments, from a small individual feature on the solar disc. Real-time TV was used by the crew to monitor performance of the telescope, transmit to the ground and record. The exposed films were retrieved by astronaut extravehicular activities. The Marshall Space Flight Center had program management responsibility for the development of the Skylab hardware and experiments.

Spectroscopic observations of comets

NASA Technical Reports Server (NTRS)

1982-01-01

Development of a spectrograph using a microchannel plate intensifier for observing faint comets is described. The spectrograph is capable of obtaining useful spectra of objects as faint as M(2) = 18. The increased guiding efficiency achieved by the optical coupling of the ISIT vidicon of the 154 cm telescope has resulted in a better signal to noise ratio. The ability to take a direct image of the comet aids in the interpretation of the spatial profile of the emissions. Spectra of comets Schwassmann-Wachmann 1, Bradfield, Encke, Tuttle, and Stephen-Oterma are discussed.

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.;

Multipurpose Hyperspectral Imaging System

NASA Technical Reports Server (NTRS)

Mao, Chengye; Smith, David; Lanoue, Mark A.; Poole, Gavin H.; Heitschmidt, Jerry; Martinez, Luis; Windham, William A.; Lawrence, Kurt C.; Park, Bosoon

2005-01-01

A hyperspectral imaging system of high spectral and spatial resolution that incorporates several innovative features has been developed to incorporate a focal plane scanner (U.S. Patent 6,166,373). This feature enables the system to be used for both airborne/spaceborne and laboratory hyperspectral imaging with or without relative movement of the imaging system, and it can be used to scan a target of any size as long as the target can be imaged at the focal plane; for example, automated inspection of food items and identification of single-celled organisms. The spectral resolution of this system is greater than that of prior terrestrial multispectral imaging systems. Moreover, unlike prior high-spectral resolution airborne and spaceborne hyperspectral imaging systems, this system does not rely on relative movement of the target and the imaging system to sweep an imaging line across a scene. This compact system (see figure) consists of a front objective mounted at a translation stage with a motorized actuator, and a line-slit imaging spectrograph mounted within a rotary assembly with a rear adaptor to a charged-coupled-device (CCD) camera. Push-broom scanning is carried out by the motorized actuator which can be controlled either manually by an operator or automatically by a computer to drive the line-slit across an image at a focal plane of the front objective. To reduce the cost, the system has been designed to integrate as many as possible off-the-shelf components including the CCD camera and spectrograph. The system has achieved high spectral and spatial resolutions by using a high-quality CCD camera, spectrograph, and front objective lens. Fixtures for attachment of the system to a microscope (U.S. Patent 6,495,818 B1) make it possible to acquire multispectral images of single cells and other microscopic objects.

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.

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.

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.

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.

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.

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.

Development of integrated photonic-dicers for reformatting the point-spread-function of a telescope

NASA Astrophysics Data System (ADS)

MacLachlan, David G.; Harris, Robert; Choudhury, Debaditya; Arriola, Alexander; Brown, Graeme; Allington-Smith, Jeremy; Thomson, Robert R.

2014-07-01

Spectroscopy is a technique of paramount importance to astronomy, as it enables the chemical composition, distances and velocities of celestial objects to be determined. As the diameter of a ground-based telescope increases, the pointspread- function (PSF) becomes increasingly degraded due to atmospheric seeing. A degraded PSF requires a larger spectrograph slit-width for efficient coupling and current spectrographs for large telescopes are already on the metre scale. This presents numerous issues in terms of manufacturability, cost and stability. As proposed in 2010 by Bland-Hawthorn et al, one approach which may help to improve spectrograph stability is a guided wave transition, known as a "photonic-lantern". These devices enable the low-loss reformatting of a multimode PSF into a diffraction-limited source (in one direction). This pseudo-slit can then be used as the input to a traditional spectrograph operating at the diffraction limit. In essence, this approach may enable the use of diffractionlimited spectrographs on large telescopes without an unacceptable reduction in throughput. We have recently demonstrated that ultrafast laser inscription can be used to realize "integrated" photoniclanterns, by directly writing three-dimensional optical waveguide structures inside a glass substrate. This paper presents our work on developing ultrafast laser inscribed devices capable of reformatting a multimode telescope PSF into a diffraction-limited slit.

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

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.

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.

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 ).

Ultraviolet micro-Raman spectrograph for the detection of small numbers of bacterial cells

NASA Astrophysics Data System (ADS)

Chadha, S.; Nelson, W. H.; Sperry, J. F.

1993-11-01

The construction of a practical UV micro-Raman spectrograph capable of selective excitation of bacterial cells and other microscopic samples has been described. A reflective objective is used to focus cw laser light on a sample and at the same time collect the scattered light at 180°. With the aid of a quartz lens the image produced is focused on the slits of a spectrograph equipped with a single 2400 grooves/mm grating optimized for 250 nm. Spectra were detected by means of a blue-intensified diode array detector. Resonance Raman spectra of Bacillus subtilis and Flavobacterium capsulatum excited by the 257.2 nm output of a cw laser were recorded in the 900-1800 cm-1 region. Bacterial cells were immobilized on a quartz plate by means of polylysine and were counted visually. Cooling was required to retard sample degradation. Sample sizes ranged from 1 to 50 cells with excitation times varying from 15 to 180 s. Excellent spectra have been obtained from 20 cells in 15 s using a spectrograph having only 3% throughput.

LEMUR: Large European Module for Solar Ultraviolet Research

NASA Technical Reports Server (NTRS)

Teriaca, Luca; Vincenzo, Andretta; Auchere, Frederic; Brown, Charles M.; Buchlin, Eric; Cauzzi, Gianna; Culhane, J. Len; Curdt, Werner; Davila, Joseph M.; Del Zanna, Giulio;

PCF-Based Cavity Enhanced Spectroscopic Sensors for Simultaneous Multicomponent Trace Gas Analysis

PubMed Central

Nakaema, Walter M.; Hao, Zuo-Qiang; Rohwetter, Philipp; Wöste, Ludger; Stelmaszczyk, Kamil

2011-01-01

A multiwavelength, multicomponent CRDS gas sensor operating on the basis of a compact photonic crystal fibre supercontinuum light source has been constructed. It features a simple design encompassing one radiation source, one cavity and one detection unit (a spectrograph with a fitted ICCD camera) that are common for all wavelengths. Multicomponent detection capability of the device is demonstrated by simultaneous measurements of the absorption spectra of molecular oxygen (spin-forbidden b-X branch) and water vapor (polyads 4v, 4v + δ) in ambient atmospheric air. Issues related to multimodal cavity excitation, as well as to obtaining the best signal-to-noise ratio are discussed together with methods for their practical resolution based on operating the cavity in a “quasi continuum” mode and setting long camera gate widths, respectively. A comprehensive review of multiwavelength CRDS techniques is also given. PMID:22319372

The science enabled by the Maunakea Spectroscopic Explorer

NASA Astrophysics Data System (ADS)

Martin, N. F.; Babusiaux, C.

2017-12-01

With its unique wide-field, multi-object, and dedicated spectroscopic capabilities, the Maunakea Spectroscopic Explorer (MSE) is a powerful facility to shed light on the faint Universe. Built around an upgrade of the Canada-France Hawaii Telescope (CFHT) to a 11.25-meter telescope with a dedicated ˜1.5 deg^2, 4,000-fiber wide-field spectrograph that covers the optical and near-infrared wavelengths at resolutions between 2,500 and 40,000, the MSE is the essential follow-up complement to the current and next generations of multi-wavelength imaging surveys, such as the LSST, Gaia, Euclid, eROSITA, SKA, and WFIRST, and is an ideal feeder facility for the extremely large telescopes that are currently being built (E-ELT, GMT, and TMT). The science enabled by the MSE is vast and would have an impact on almost all aspects of astronomy research.

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.

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.

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.

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.

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.

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.

The Hubble Spectroscopic Legacy Archive

NASA Astrophysics Data System (ADS)

Peeples, M.; Tumlinson, J.; Fox, A.; Aloisi, A.; Fleming, S.; Jedrzejewski, R.; Oliveira, C.; Ayres, T.; Danforth, C.; Keeney, B.; Jenkins, E.

2017-04-01

With no future space ultraviolet instruments currently planned, the data from the UV spectrographs aboard the Hubble Space Telescope have a legacy value beyond their initial science goals. The goal of the Hubble Spectroscopic Legacy Archive(HSLA) is to provide to the community new science-grade combined spectra for all publicly available data obtained by the Cosmic Origins Spectrograph (COS)and the Space Telescope Imaging Spectrograph (STIS). These data are packaged into "smart archives" according to target type and scientific themes to facilitate the construction of archival samples for common science uses. A new "quick look" capability makes the data easy for users to quickly access, assess the quality of,and download for archival science. The first generation of these products for the far-ultraviolet (FUV) modes of COS was made available online via the Mikulski Archive for Space Telescopes (MAST) in early 2016 and updated in early 2017; future releases will include COS/NUV and STIS/UV data.

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.

Constraining hot Jupiter’s atmospheric structure and dynamics through Doppler shifted emission spectra

NASA Astrophysics Data System (ADS)

Zhang, Jisheng; Kempton, Eliza; Rauscher, Emily

2017-01-01

In recent years, astronomers have begun successfully observing the atmospheres of extrasolar planets using ground-based telescopes equipped with spectrographs capable of observing at high spectral resolution (R~105). Such studies are capable of diagnosing the atmospheric structure, composition, and dynamics (winds and rotation) of both transiting and non-transiting exoplanets. However, few studies have examined how the 3-D atmospheric dynamics could alter the emitted light of hot Jupiters at such high spectral resolution. Here, we present a model to explore such influence on the hot Jupiters’ thermal emission spectra. Our aim is to investigate the extent to which the effects of 3-D atmospheric dynamics are imprinted on planet-averaged thermal emission spectra. We couple together a 3-D general circulation model of hot Jupiter atmospheric dynamics (Rauscher & Menou, 2012) with a radiative transfer solver to predict the planet’s disk-integrated emission spectrum as a function of its orbital phase. For the first time, we self-consistently include the effects of the line-of-sight atmospheric motions (resulting from winds and rotation) in the calculation to produce Doppler-shifted spectral line profiles that result from the atmospheric dynamics. We focus our study on three benchmark hot Jupiters, HD 189733b, HD 209458b, and WASP-43b which have been the focus of previous detailed observational studies. We find that the high-resolution Doppler shifted thermal emission spectra can be used to diagnose key properties of the dynamical atmosphere - the planet’s longitudinal temperature and wind structure, and its rotation rate.

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: 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).

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.

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).

Astrophysics on the Edge: New Instrumental Developments at the ING

NASA Astrophysics Data System (ADS)

Santander-García, M.; Rodríguez-Gil, P.; Tulloch, S.; Rutten, R. G. M.

Present and future key instruments at the Isaac Newton Group of Telescopes (ING) are introduced, and their corresponding latest scientific highlights are presented. GLAS (Ground-layer Laser Adaptive optics System): The recently installed 515 nm laser, mounted on the WHT (William Herschel Telescope), produces a bright artificial star at a height of 15 km. This enables almost full-sky access to Adaptive Optics observations. Recent commissioning observations with the NAOMI+GLAS system showed that very significant improvement in image quality can be obtained, e.g. down to 0.16 arcsec in the H band. QUCAM2 and QUCAM3: Two Low Light Level (L3) CCD cameras for fast or faint-object spectroscopy with the twin-armed ISIS spectrograph at the WHT. Their use opens a new window of high time-frequency observations, as well as access to fainter objects. They are powerful instruments for research on compact objects such as white dwarfs, neutron stars or black holes, stellar pulsations, and compact binaries.HARPS-NEF (High-Accuracy Radial-velocity Planet Searcher of the New Earths Facility): An extremely stable, high-resolution (R ˜ 120, 000) spectrograph for the WHT which is being constructed for commissioning in 2009-2010. Its radial velocity stability of < 1 m s- 1 may in the future be even further improved by using a Fabry-Perot laser-comb, a wavelength calibration unit capable of achieving an accuracy of 1 cm s- 1. This instrument will effectively allow to search for earth-like exoplanets.

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.

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.

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.

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.

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.

Target Selection for the SDSS-III MARVELS Survey

NASA Astrophysics Data System (ADS)

Paegert, Martin; Stassun, Keivan G.; De Lee, Nathan; Pepper, Joshua; Fleming, Scott W.; Sivarani, Thirupathi; Mahadevan, Suvrath; Mack, Claude E., III; Dhital, Saurav; Hebb, Leslie; Ge, Jian

2015-06-01

We present the target selection process for the Multi-object APO Radial Velocity Exoplanets Large-area Survey (MARVELS), which is part of the Sloan Digital Sky Survey (SDSS) III. MARVELS is a medium-resolution (R ∼ 11,000) multi-fiber spectrograph capable of obtaining radial velocities for 60 objects at a time in order to find brown dwarfs and giant planets. The survey was configured to target dwarf stars with effective temperatures approximately between 4500 and 6250 K. For the first 2 years MARVELS relied on low-resolution spectroscopic pre-observations to estimate the effective temperature and log (g) for candidate stars and then selected suitable dwarf stars from this pool. Ultimately, the pre-observation spectra proved ineffective at filtering out giant stars; many giants were incorrectly classified as dwarfs, resulting in a giant contamination rate of ∼30% for the first phase of the MARVELS survey. Thereafter, the survey instead applied a reduced proper motion cut to eliminate giants and used the Infrared Flux Method to estimate effective temperatures, using only extant photmetric and proper-motion catalog information. The target selection method introduced here may be useful for other surveys that need to rely on extant catalog data for selection of specific stellar populations.

Experimental station for ultrafast extreme ultraviolet spectroscopy for non-equilibrium dynamics in warm dense matter

NASA Astrophysics Data System (ADS)

Lee, Jong-won; Geng, Xiaotao; Jung, Jae Hyung; Cho, Min Sang; Yang, Seong Hyeok; Jo, Jawon; Lee, Chang-lyoul; Cho, Byoung Ick; Kim, Dong-Eon

2018-07-01

Recent interest in highly excited matter generated by intense femtosecond laser pulses has led to experimental methods that directly investigate ultrafast non-equilibrium electronic and structural dynamics. We present a tabletop experimental station for the extreme ultraviolet (EUV) spectroscopy used to trace L-edge dynamics in warm dense aluminum with a temporal resolution of a hundred femtoseconds. The system consists of the EUV probe generation part via a high-order harmonic generation process of femtosecond laser pulses with atomic clusters, a beamline with high-throughput optics and a sample-refreshment system of nano-foils utilizing the full repetition rate of the probe, and a flat-field EUV spectrograph. With the accumulation of an order of a hundred shots, a clear observation of the change in the aluminum L-shell absorption was achieved with a temporal resolution of 90 fs in a 600-fs window. The signature of a non-equilibrium electron distribution over a 10-eV range and its evolution to a 1-eV Fermi distribution are observed. This demonstrates the capability of this apparatus to capture the non-equilibrium electron-hole dynamics in highly excited warm dense matter conditions.

ESPRESSO: projecting a rocky exoplanet hunter for the VLT

NASA Astrophysics Data System (ADS)

Mégevand, Denis; Herreros, José-Miguel; Zerbi, Filippo; Cabral, Alexandre; Di Marcantonio, Paolo; Lovis, Christophe; Pepe, Francesco; Cristiani, Stefano; Rebolo, Rafael; Santos, Nuno C.

2010-07-01

ESPRESSO is a high-resolution, highly stable spectrograph for the VLT. It will inherit and enhance most capabilities from HARPS and UVES, combining both stability and efficiency. The main science driver will be the detection and characterization of Earth-like planets, but many additional science cases will benefit from its highly stable spectroscopic observations. The facility will be installed at the combined Coudé focus of the VLT and may be linked with any of the four UT telescopes, enabling thus a great flexibility for the efficient use of telescope time. This particularity makes the interface with the VLT more complex than for an instrument fed by a single telescope. It impacts on the complexity of the relationship between the consortium providing the instrument and ESO, the customer. The targeted high RV accuracy requires very high performances in stability and resolution, which in turn require adequate technical solutions at several levels. This paper describes the instrument system and subsystems, enlightening the most valuable differences between ESPRESSO and it's predecessors, the details of the project, entering now the design phases, the ESPRESSO consortium, composed of Italian, Portuguese, Spanish and Swiss institutes, and the relationship between the consortium and ESO.

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.

The Development of Replicated Optical Integral Field Spectrographs and their Application to the Study of Lyman-alpha Emission at Moderate Redshifts

NASA Astrophysics Data System (ADS)

Chonis, Taylor Steven

In the upcoming era of extremely large ground-based astronomical telescopes, the design of wide-field spectroscopic survey instrumentation has become increasingly complex due to the linear growth of instrument pupil size with telescope diameter for a constant spectral resolving power. The upcoming Visible Integral field Replicable Unit Spectrograph (VIRUS), a baseline array of 150 copies of a simple integral field spectrograph that will be fed by 3:36 x 104 optical fibers on the upgraded Hobby-Eberly Telescope (HET) at McDonald Observatory, represents one of the first uses of large-scale replication to break the relationship between instrument pupil size and telescope diameter. By dividing the telescope's field of view between a large number of smaller and more manageable instruments, the total information grasp of a traditional monolithic survey spectrograph can be achieved at a fraction of the cost and engineering complexity. To highlight the power of this method, VIRUS will execute the HET Dark Energy Experiment (HETDEX) and survey & 420 degrees2 of sky to an emission line flux limit of ˜ 10-17 erg s-1 cm -2 to detect ˜ 106 Lyman-alpha emitting galaxies (LAEs) as probes of large-scale structure at redshifts of 1:9 < z < 3:5. HETDEX will precisely measure the evolution of dark energy at that epoch, and will simultaneously amass an LAE sample that will be unprecedented for extragalactic astrophysics at the redshifts of interest. Large-scale replication has clear advantages to increasing the total information grasp of a spectrograph, but there are also challenges. In this dissertation, two of these challenges with respect to VIRUS are detailed. First, the VIRUS cryogenic system is discussed, specifically the design and tests of a novel thermal connector and internal camera croygenic components that link the 150 charge-coupled device detectors to the instrument's liquid nitrogen distribution system. Second, the design, testing, and mass production of the suite of volume phase holographic (VPH) diffraction gratings for VIRUS is presented, which highlights the challenge and success associated with producing of a very large number of highly customized optical elements whose performance is crucial to meeting the efficiency requirements of the spectrograph system. To accommodate VIRUS, the HET is undergoing a substantial wide-field upgrade to increase its field of view to 22' in diameter. The previous HET facility Low Resolution Spectrograph (LRS), which was directly fed by the telescope's previous spherical aberration corrector, must be removed from the prime focus instrument package as a result of the telescope upgrades and instead be fiber-coupled to the telescope focal plane. For a similar cost as modifying LRS to accommodate these changes, a new second generation instrument (LRS2) will be based on the VIRUS unit spectrograph. The design, operational concept, construction, and laboratory testing and characterization of LRS2 is the primary focus of this dissertation, which highlights the benefits of leveraging the large engineering investment, economies of scale, and laboratory and observatory infrastructure associated with the massively replicated VIRUS instrument. LRS2 will provide integral field spectroscopy for a seeing-limited field of 12" x 6". The multiplexed VIRUS framework facilitates broad wavelength coverage from 370 nm to 1.0 mum spread between two dual-channel spectrographs at a moderate spectral resolving power of R ≈ 2000. The design departures from VIRUS are presented, including the novel integral field unit, VPH grism dispersers, and various optical changes for accommodating the broadband wavelength coverage. Laboratory testing has verified that LRS2 largely meets its image quality specification and is nearly ready for delivery to the HET where its final verification and validation tasks will be executed. LRS2 will enable the continuation of most legacy LRS science programs and provide improved capability for future investigations. (Abstract shortened by ProQuest.).

Solar glint suppression in compact planetary ultraviolet spectrographs

NASA Astrophysics Data System (ADS)

Davis, Michael W.; Cook, Jason C.; Grava, Cesare; Greathouse, Thomas K.; Gladstone, G. Randall; Retherford, Kurt D.

2015-08-01

Solar glint suppression is an important consideration in the design of compact photon-counting ultraviolet spectrographs. Southwest Research Institute developed the Lyman Alpha Mapping Project for the Lunar Reconnaissance Orbiter (launch in 2009), and the Ultraviolet Spectrograph on Juno (Juno-UVS, launch in 2011). Both of these compact spectrographs revealed minor solar glints in flight that did not appear in pre-launch analyses. These glints only appeared when their respective spacecraft were operating outside primary science mission parameters. Post-facto scattered light analysis verifies the geometries at which these glints occurred and why they were not caught during ground testing or nominal mission operations. The limitations of standard baffle design at near-grazing angles are discussed, as well as the importance of including surface scatter properties in standard stray light analyses when determining solar keep-out efficiency. In particular, the scattered light analysis of these two instruments shows that standard "one bounce" assumptions in baffle design are not always enough to prevent scattered sunlight from reaching the instrument focal plane. Future builds, such as JUICE-UVS, will implement improved scattered and stray light modeling early in the design phase to enhance capabilities in extended mission science phases, as well as optimize solar keep out volume.

High-efficiency in situ resonant inelastic x-ray scattering (iRIXS) endstation at the Advanced Light Source

NASA Astrophysics Data System (ADS)

Qiao, Ruimin; Li, Qinghao; Zhuo, Zengqing; Sallis, Shawn; Fuchs, Oliver; Blum, Monika; Weinhardt, Lothar; Heske, Clemens; Pepper, John; Jones, Michael; Brown, Adam; Spucces, Adrian; Chow, Ken; Smith, Brian; Glans, Per-Anders; Chen, Yanxue; Yan, Shishen; Pan, Feng; Piper, Louis F. J.; Denlinger, Jonathan; Guo, Jinghua; Hussain, Zahid; Chuang, Yi-De; Yang, Wanli

2017-03-01

An endstation with two high-efficiency soft x-ray spectrographs was developed at Beamline 8.0.1 of the Advanced Light Source, Lawrence Berkeley National Laboratory. The endstation is capable of performing soft x-ray absorption spectroscopy, emission spectroscopy, and, in particular, resonant inelastic soft x-ray scattering (RIXS). Two slit-less variable line-spacing grating spectrographs are installed at different detection geometries. The endstation covers the photon energy range from 80 to 1500 eV. For studying transition-metal oxides, the large detection energy window allows a simultaneous collection of x-ray emission spectra with energies ranging from the O K-edge to the Ni L-edge without moving any mechanical components. The record-high efficiency enables the recording of comprehensive two-dimensional RIXS maps with good statistics within a short acquisition time. By virtue of the large energy window and high throughput of the spectrographs, partial fluorescence yield and inverse partial fluorescence yield signals could be obtained for all transition metal L-edges including Mn. Moreover, the different geometries of these two spectrographs (parallel and perpendicular to the horizontal polarization of the beamline) provide contrasts in RIXS features with two different momentum transfers.

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

Qiao, Ruimin; Li, Qinghao; Zhuo, Zengqing

In this paper, an endstation with two high-efficiency soft x-ray spectrographs was developed at Beamline 8.0.1 of the Advanced Light Source, Lawrence Berkeley National Laboratory. The endstation is capable of performing soft x-ray absorption spectroscopy, emission spectroscopy, and, in particular, resonant inelastic soft x-ray scattering (RIXS). Two slit-less variable line-spacing grating spectrographs are installed at different detection geometries. The endstation covers the photon energy range from 80 to 1500 eV. For studying transition-metal oxides, the large detection energy window allows a simultaneous collection of x-ray emission spectra with energies ranging from the O K-edge to the Ni L-edge without movingmore » any mechanical components. The record-high efficiency enables the recording of comprehensive two-dimensional RIXS maps with good statistics within a short acquisition time. By virtue of the large energy window and high throughput of the spectrographs, partial fluorescence yield and inverse partial fluorescence yield signals could be obtained for all transition metal L-edges including Mn. Finally and moreover, the different geometries of these two spectrographs (parallel and perpendicular to the horizontal polarization of the beamline) provide contrasts in RIXS features with two different momentum transfers.« less

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.

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.

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.

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.

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.

Current and Future Capabilities of the 74-inch Telescope of Kottamia Astronomical Observatory in Egypt

NASA Astrophysics Data System (ADS)

Azzam, Y. A.; Ali, G. B.; Ismail, H. A.; Haroon, A.; Selim, I.

In this paper, we are going to introduce the Kottamia Astronomical Observatory, KAO, to the astronomical community. The current status of the telescope together with the available instrumentations is described. An upgrade stage including a new optical system and a computer controlling of both the telescope and dome are achieved. The specifications of a set of CCD cameras for direct imaging and spectroscopy are given. A grating spectrograph is recently gifted to KAO from Okayama Astrophysical Observatory, OAO, of the National Astronomical Observatories in Japan. This spectrograph is successfully tested and installed at the F/18 Cassegrain focus of the KAO 74" telescope.

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.

MEGARA, the new intermediate-resolution optical IFU and MOS for GTC: getting ready for the telescope

NASA Astrophysics Data System (ADS)

Gil de Paz, A.; Carrasco, E.; Gallego, J.; Iglesias-Páramo, J.; Cedazo, R.; García Vargas, M. L.; Arrillaga, X.; Avilés, J. L.; Cardiel, N.; Carrera, M. A.; Castillo-Morales, A.; Castillo-Domínguez, E.; de la Cruz García, J. M.; Esteban San Román, S.; Ferrusca, D.; Gómez-Álvarez, P.; Izazaga-Pérez, R.; Lefort, B.; López-Orozco, J. A.; Maldonado, M.; Martínez-Delgado, I.; Morales Durán, I.; Mujica, E.; Páez, G.; Pascual, S.; Pérez-Calpena, A.; Picazo, P.; Sánchez-Penim, A.; Sánchez-Blanco, E.; Tulloch, S.; Velázquez, M.; Vílchez, J. M.; Zamorano, J.; Aguerri, A. L.; Barrado y Naváscues, D.; Bertone, E.; Cava, A.; Cenarro, J.; Chávez, M.; García, M.; García-Rojas, J.; Guichard, J.; González-Delgado, R.; Guzmán, R.; Herrero, A.; Huélamo, N.; Hughes, D. H.; Jiménez-Vicente, J.; Kehrig, C.; Marino, R. A.; Márquez, I.; Masegosa, J.; Mayya, Y. D.; Méndez-Abreu, J.; Mollá, M.; Muñoz-Tuñón, C.; Peimbert, M.; Pérez-González, P. G.; Pérez Montero, E.; Rodríguez, M.; Rodríguez-Espinosa, J. M.; Rodríguez-Merino, L.; Rodríguez-Muñoz, L.; Rosa-González, D.; Sánchez-Almeida, J.; Sánchez Contreras, C.; Sánchez-Blázquez, P.; Sánchez Moreno, F. M.; Sánchez, S. F.; Sarajedini, A.; Silich, S.; Simón-Díaz, S.; Tenorio-Tagle, G.; Terlevich, E.; Terlevich, R.; Torres-Peimbert, S.; Trujillo, I.; Tsamis, Y.; Vega, O.

2016-08-01

MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía) is an optical Integral-Field Unit (IFU) and Multi-Object Spectrograph (MOS) designed for the GTC 10.4m telescope in La Palma that is being built by a Consortium led by UCM (Spain) that also includes INAOE (Mexico), IAA-CSIC (Spain), and UPM (Spain). The instrument is currently finishing AIV and will be sent to GTC on November 2016 for its on-sky commissioning on April 2017. The MEGARA IFU fiber bundle (LCB) covers 12.5x11.3 arcsec2 with a spaxel size of 0.62 arcsec while the MEGARA MOS mode allows observing up to 92 objects in a region of 3.5x3.5 arcmin2 around the IFU. The IFU and MOS modes of MEGARA will provide identical intermediate-to-high spectral resolutions (RFWHM 6,000, 12,000 and 18,700, respectively for the low-, mid- and high-resolution Volume Phase Holographic gratings) in the range 3700-9800ÅÅ. An x-y mechanism placed at the pseudo-slit position allows (1) exchanging between the two observing modes and (2) focusing the spectrograph for each VPH setup. The spectrograph is a collimator-camera system that has a total of 11 VPHs simultaneously available (out of the 18 VPHs designed and being built) that are placed in the pupil by means of a wheel and an insertion mechanism. The custom-made cryostat hosts a 4kx4k 15-μm CCD. The unique characteristics of MEGARA in terms of throughput and versatility and the unsurpassed collecting are of GTC make of this instrument the most efficient tool to date to analyze astrophysical objects at intermediate spectral resolutions. In these proceedings we present a summary of the instrument characteristics and the results from the AIV phase. All subsystems have been successfully integrated and the system-level AIV phase is progressing as expected.

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.

A search for stars of very low metal abundance. VI. Detailed abundances of 313 metal-poor stars

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

Roederer, Ian U.; Preston, George W.; Thompson, Ian B.

2014-06-01

We present radial velocities, equivalent widths, model atmosphere parameters, and abundances or upper limits for 53 species of 48 elements derived from high resolution optical spectroscopy of 313 metal-poor stars. A majority of these stars were selected from the metal-poor candidates of the HK Survey of Beers, Preston, and Shectman. We derive detailed abundances for 61% of these stars for the first time. Spectra were obtained during a 10 yr observing campaign using the Magellan Inamori Kyocera Echelle spectrograph on the Magellan Telescopes at Las Campanas Observatory, the Robert G. Tull Coudé Spectrograph on the Harlan J. Smith Telescope atmore » McDonald Observatory, and the High Resolution Spectrograph on the Hobby-Eberly Telescope at McDonald Observatory. We perform a standard LTE abundance analysis using MARCS model atmospheres, and we apply line-by-line statistical corrections to minimize systematic abundance differences arising when different sets of lines are available for analysis. We identify several abundance correlations with effective temperature. A comparison with previous abundance analyses reveals significant differences in stellar parameters, which we investigate in detail. Our metallicities are, on average, lower by ≈0.25 dex for red giants and ≈0.04 dex for subgiants. Our sample contains 19 stars with [Fe/H] ≤–3.5, 84 stars with [Fe/H] ≤–3.0, and 210 stars with [Fe/H] ≤–2.5. Detailed abundances are presented here or elsewhere for 91% of the 209 stars with [Fe/H] ≤–2.5 as estimated from medium resolution spectroscopy by Beers, Preston, and Shectman. We will discuss the interpretation of these abundances in subsequent papers.« less

Pristine Survey : High-Resolution Spectral Analyses of New Metal-poor Stars

NASA Astrophysics Data System (ADS)

Venn, Kim; Starkenburg, Else; Martin, Nicolas; Kielty, Collin; Youakim, Kris; Arnetsen, Anke

2018-06-01

The Pristine survey (Starkenburg et al. 2017) is a new and very successful metal-poor star survey. Combining high-quality narrow-band CaHK CFHT/MegaCam photometry with existing broadband photometry from SDSS, then very metal-poor stars have been found as confirmed from low-resolution spectroscopy (Youakim et al. 2017). Furthermore, we have extended this survey towards the Galactic bulge in a pilot program to test the capabilities in the highly crowded and (inhomogeneously) extincted bulge (Arentsen et al. 2018). High resolution spectral follow-up analyses have been initiated at the CFHT with Espadons (V<15) and the Gemini/GRACES long optical fibre that also feeds the Espadons spectrograph (15

The Stratospheric Observatory for Infrared Astronomy (SOFIA)

NASA Astrophysics Data System (ADS)

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

2008-07-01

The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (SOFIA) Project will operate a 2.5-meter infrared airborne telescope in a Boeing 747SP. Flying in the stratosphere at altitudes as high as 45,000 feet, SOFIA enables observations in the infrared and submillimeter region with an average transmission of 80%. SOFIA has a wide instrument complement including broadband imaging cameras, 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 first generation and future instruments will enable SOFIA to make unique contributions to a broad array of science topics. SOFIA began its post-modification test flight series on April 26, 2007 in Waco, Texas and will conclude in winter of 2008-09. SOFIA will be staged out of Dryden's aircraft operations facility at Palmdale, Site 9, CA for science operations. The SOFIA Science Center will be at NASA Ames Research Center, Moffet Field, CA. First science flights will begin in 2009, the next instrument call and first General Observer science call will be in 2010, and a full operations schedule of ~120 flights per year will be reached by 2014. 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 and early mission science are discussed.

The Stratospheric Observatory for Infrared Astronomy (SOFIA)

NASA Astrophysics Data System (ADS)

Gehrz, Robert

The joint U.S. and German Stratospheric Observatory for Infrared Astronomy (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 at altitudes as high as 45,000 feet, SOFIA enables observations throughout the infrared and submillimeter region with an average transmission of greater than 80 percent. SOFIA has a wide instrument complement including 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 first generation and future instruments will enable SOFIA to make unique contributions to a broad array of science topics. SOFIA began its post-modification test flight series on April 26, 2007 in Waco, Texas. The test flight series continues at NASA Dryden Flight Research Center, California. SOFIA will be staged out of Dryden's new aircraft operations facility at Palmdale, CA starting in December, 2007. First science flights will begin in 2009, the next instrument call and the first General Observer science call will be in 2010, and a full operations schedule of about 120 flights per year will be reached by 2014. 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.

Combining laser frequency combs and iodine cell calibration techniques for Doppler detection of exoplanets

NASA Astrophysics Data System (ADS)

Cahoy, Kerri; Fischer, Debra; Spronck, Julien; DeMille, David

2010-07-01

Exoplanets can be detected from a time series of stellar spectra by looking for small, periodic shifts in the absorption features that are consistent with Doppler shifts caused by the presence of an exoplanet, or multiple exoplanets, in the system. While hundreds of large exoplanets have already been discovered with the Doppler technique (also called radial velocity), our goal is to improve the measurement precision so that many Earth-like planets can be detected. The smaller mass and longer period of true Earth analogues require the ability to detect a reflex velocity of ~10 cm/s over long time periods. Currently, typical astronomical spectrographs calibrate using either Iodine absorptive cells or Thorium Argon lamps and achieve ~10 m/s precision, with the most stable spectrographs pushing down to ~2 m/s. High velocity precision is currently achieved at HARPS by controlling the thermal and pressure environment of the spectrograph. These environmental controls increase the cost of the spectrograph, and it is not feasible to simply retrofit existing spectrometers. We propose a fiber-fed high precision spectrograph design that combines the existing ~5000-6000 A Iodine calibration system with a high-precision Laser Frequency Comb (LFC) system from ~6000-7000 A that just meets the redward side of the Iodine lines. The scientific motivation for such a system includes: a 1000 A span in the red is currently achievable with LFC systems, combining the two calibration methods increases the wavelength range by a factor of two, and moving redward decreases the "noise" from starspots. The proposed LFC system design employs a fiber laser, tunable serial Fabry-Perot cavity filters to match the resolution of the LFC system to that of standard astronomical spectrographs, and terminal ultrasonic vibration of the multimode fiber for a stable point spread function.

High-resolution broadband spectroscopy using externally dispersed interferometry at the Hale telescope: part 2, photon noise theory

NASA Astrophysics Data System (ADS)

Erskine, David J.; Edelstein, Jerry; Wishnow, Edward; Sirk, Martin; Muirhead, Philip S.; Muterspaugh, Matthew W.; Lloyd, James P.

2016-10-01

High-resolution broadband spectroscopy at near-infrared (NIR) wavelengths (950 to 2450 nm) has been performed using externally dispersed interferometry (EDI) at the Hale telescope at Mt. Palomar, with the TEDI interferometer mounted within the central hole of the 200-in. primary mirror in series with the comounted TripleSpec NIR echelle spectrograph. These are the first multidelay EDI demonstrations on starlight. We demonstrated very high (10×) resolution boost and dramatic (20× or more) robustness to point spread function wavelength drifts in the native spectrograph. Data analysis, results, and instrument noise are described in a companion paper (part 1). This part 2 describes theoretical photon limited and readout noise limited behaviors, using simulated spectra and instrument model with noise added at the detector. We show that a single interferometer delay can be used to reduce the high frequency noise at the original resolution (1× boost case), and that except for delays much smaller than the native response peak half width, the fringing and nonfringing noises act uncorrelated and add in quadrature. This is due to the frequency shifting of the noise due to the heterodyning effect. We find a sum rule for the noise variance for multiple delays. The multiple delay EDI using a Gaussian distribution of exposure times has noise-to-signal ratio for photon-limited noise similar to a classical spectrograph with reduced slitwidth and reduced flux, proportional to the square root of resolution boost achieved, but without the focal spot limitation and pixel spacing Nyquist limitations. At low boost (˜1×) EDI has ˜1.4× smaller noise than conventional, and at >10× boost, EDI has ˜1.4× larger noise than conventional. Readout noise is minimized by the use of three or four steps instead of 10 of TEDI. Net noise grows as step phases change from symmetrical arrangement with wavenumber across the band. For three (or four) steps, we calculate a multiplicative bandwidth of 1.8:1 (2.3:1), sufficient to handle the visible band (400 to 700 nm, 1.8:1) and most of TripleSpec (2.6:1).

High-resolution broadband spectroscopy using externally dispersed interferometry at the Hale telescope: Part 2, photon noise theory

DOE PAGES

Erskine, David J.; Edelstein, Jerry; Wishnow, Edward; ...

2016-10-01

High-resolution broadband spectroscopy at near-infrared (NIR) wavelengths (950 to 2450 nm) has been performed using externally dispersed interferometry (EDI) at the Hale telescope at Mt. Palomar, with the TEDI interferometer mounted within the central hole of the 200-in. primary mirror in series with the comounted TripleSpec NIR echelle spectrograph. These are the first multidelay EDI demonstrations on starlight. We demonstrated very high (10×) resolution boost and dramatic (20× or more) robustness to point spread function wavelength drifts in the native spectrograph. Data analysis, results, and instrument noise are described in a companion paper (part 1). This part 2 describes theoreticalmore » photon limited and readout noise limited behaviors, using simulated spectra and instrument model with noise added at the detector. We show that a single interferometer delay can be used to reduce the high frequency noise at the original resolution (1× boost case), and that except for delays much smaller than the native response peak half width, the fringing and nonfringing noises act uncorrelated and add in quadrature. This is due to the frequency shifting of the noise due to the heterodyning effect. We find a sum rule for the noise variance for multiple delays. The multiple delay EDI using a Gaussian distribution of exposure times has noise-to-signal ratio for photon-limited noise similar to a classical spectrograph with reduced slitwidth and reduced flux, proportional to the square root of resolution boost achieved, but without the focal spot limitation and pixel spacing Nyquist limitations. At low boost (~1×) EDI has ~1.4× smaller noise than conventional, and at >10× boost, EDI has ~1.4× larger noise than conventional. Readout noise is minimized by the use of three or four steps instead of 10 of TEDI. Net noise grows as step phases change from symmetrical arrangement with wavenumber across the band. As a result, for three (or four) steps, we calculate a multiplicative bandwidth of 1.8:1 (2.3:1), sufficient to handle the visible band (400 to 700 nm, 1.8:1) and most of TripleSpec (2.6:1).« less

High-resolution broadband spectroscopy using externally dispersed interferometry at the Hale telescope: Part 2, photon noise theory

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

Erskine, David J.; Edelstein, Jerry; Wishnow, Edward

High-resolution broadband spectroscopy at near-infrared (NIR) wavelengths (950 to 2450 nm) has been performed using externally dispersed interferometry (EDI) at the Hale telescope at Mt. Palomar, with the TEDI interferometer mounted within the central hole of the 200-in. primary mirror in series with the comounted TripleSpec NIR echelle spectrograph. These are the first multidelay EDI demonstrations on starlight. We demonstrated very high (10×) resolution boost and dramatic (20× or more) robustness to point spread function wavelength drifts in the native spectrograph. Data analysis, results, and instrument noise are described in a companion paper (part 1). This part 2 describes theoreticalmore » photon limited and readout noise limited behaviors, using simulated spectra and instrument model with noise added at the detector. We show that a single interferometer delay can be used to reduce the high frequency noise at the original resolution (1× boost case), and that except for delays much smaller than the native response peak half width, the fringing and nonfringing noises act uncorrelated and add in quadrature. This is due to the frequency shifting of the noise due to the heterodyning effect. We find a sum rule for the noise variance for multiple delays. The multiple delay EDI using a Gaussian distribution of exposure times has noise-to-signal ratio for photon-limited noise similar to a classical spectrograph with reduced slitwidth and reduced flux, proportional to the square root of resolution boost achieved, but without the focal spot limitation and pixel spacing Nyquist limitations. At low boost (~1×) EDI has ~1.4× smaller noise than conventional, and at >10× boost, EDI has ~1.4× larger noise than conventional. Readout noise is minimized by the use of three or four steps instead of 10 of TEDI. Net noise grows as step phases change from symmetrical arrangement with wavenumber across the band. As a result, for three (or four) steps, we calculate a multiplicative bandwidth of 1.8:1 (2.3:1), sufficient to handle the visible band (400 to 700 nm, 1.8:1) and most of TripleSpec (2.6:1).« less

OPTIMOS-EVE optical design of a very efficient, high-multiplex, large spectral coverage, fiber-fed spectrograph at EELT

NASA Astrophysics Data System (ADS)

Spanò, P.; Tosh, I.; Chemla, F.

2010-07-01

OPTIMOS-EVE is a fiber-fed, high-multiplex, high-efficiency, large spectral coverage spectrograph for EELT covering visible and near-infrared simultaneously. More than 200 seeing-limited objects will be observed at the same time over the full 7 arcmin field of view of the telescope, feeding the spectrograph, asking for very large multiplexing at the spectrograph side. The spectrograph consists of two identical units. Each unit will have two optimized channels to observe both visible and near-infrared wavelengths at the same time, covering from 0.37 to 1.7 micron. To maximize the scientific return, a large simultaneous spectral coverage per exposure was required, up to 1/3 of the central wavelength. Moreover, different spectral resolution modes, spanning from 5'000 to 30'000, were defined to match very different sky targets. Many different optical solutions were generated during the initial study phase in order to select that one that will maximize performances within given constraints (mass, space, cost). Here we present the results of this study, with special attention to the baseline design. Efforts were done to keep size of the optical components well within present state-of-the-art technologies. For example, large glass blank sizes were limited to ~35 cm maximum diameter. VPH gratings were selected as dispersers, to improve efficiency, following their superblaze curve. This led to scanning gratings and cameras. Optical design will be described, together with expected performances.

The GALAH survey: scientific motivation

NASA Astrophysics Data System (ADS)

De Silva, G. M.; Freeman, K. C.; Bland-Hawthorn, J.; Martell, S.; de Boer, E. Wylie; Asplund, M.; Keller, S.; Sharma, S.; Zucker, D. B.; Zwitter, T.; Anguiano, B.; Bacigalupo, C.; Bayliss, D.; Beavis, M. A.; Bergemann, M.; Campbell, S.; Cannon, R.; Carollo, D.; Casagrande, L.; Casey, A. R.; Da Costa, G.; D'Orazi, V.; Dotter, A.; Duong, L.; Heger, A.; Ireland, M. J.; Kafle, P. R.; Kos, J.; Lattanzio, J.; Lewis, G. F.; Lin, J.; Lind, K.; Munari, U.; Nataf, D. M.; O'Toole, S.; Parker, Q.; Reid, W.; Schlesinger, K. J.; Sheinis, A.; Simpson, J. D.; Stello, D.; Ting, Y.-S.; Traven, G.; Watson, F.; Wittenmyer, R.; Yong, D.; Žerjal, M.

2015-05-01

The Galactic Archaeology with HERMES (GALAH) survey is a large high-resolution spectroscopic survey using the newly commissioned High Efficiency and Resolution Multi-Element Spectrograph (HERMES) on the Anglo-Australian Telescope. The HERMES spectrograph provides high-resolution (R ˜ 28 000) spectra in four passbands for 392 stars simultaneously over a 2 deg field of view. The goal of the survey is to unravel the formation and evolutionary history of the Milky Way, using fossil remnants of ancient star formation events which have been disrupted and are now dispersed throughout the Galaxy. Chemical tagging seeks to identify such dispersed remnants solely from their common and unique chemical signatures; these groups are unidentifiable from their spatial, photometric or kinematic properties. To carry out chemical tagging, the GALAH survey will acquire spectra for a million stars down to V ˜ 14. The HERMES spectra of FGK stars contain absorption lines from 29 elements including light proton-capture elements, α-elements, odd-Z elements, iron-peak elements and n-capture elements from the light and heavy s-process and the r-process. This paper describes the motivation and planned execution of the GALAH survey, and presents some results on the first-light performance of HERMES.

A preliminary design for the GMT-Consortium Large Earth Finder (G-CLEF)

NASA Astrophysics Data System (ADS)

Szentgyorgyi, Andrew; Barnes, Stuart; Bean, Jacob; Bigelow, Bruce; Bouchez, Antonin; Chun, Moo-Young; Crane, Jeffrey D.; Epps, Harland; Evans, Ian; Evans, Janet; Frebel, Anna; Furesz, Gabor; Glenday, Alex; Guzman, Dani; Hare, Tyson; Jang, Bi-Ho; Jang, Jeong-Gyun; Jeong, Ueejong; Jordan, Andres; Kim, Kang-Min; Kim, Jihun; Li, Chih-Hao; Lopez-Morales, Mercedes; McCracken, Kenneth; McLeod, Brian; Mueller, Mark; Nah, Jakyung; Norton, Timothy; Oh, Heeyoung; Oh, Jae Sok; Ordway, Mark; Park, Byeong-Gon; Park, Chan; Park, Sung-Joon; Phillips, David; Plummer, David; Podgorski, William; Rodler, Florian; Seifahrt, Andreas; Tak, Kyung-Mo; Uomoto, Alan; Van Dam, Marcos A.; Walsworth, Ronald; Yu, Young Sam; Yuk, In-Soo

2014-08-01

The GMT-Consortium Large Earth Finder (G-CLEF) is an optical-band echelle spectrograph that has been selected as the first light instrument for the Giant Magellan Telescope (GMT). G-CLEF is a general-purpose, high dispersion spectrograph that is fiber fed and capable of extremely precise radial velocity measurements. The G-CLEF Concept Design (CoD) was selected in Spring 2013. Since then, G-CLEF has undergone science requirements and instrument requirements reviews and will be the subject of a preliminary design review (PDR) in March 2015. Since CoD review (CoDR), the overall G-CLEF design has evolved significantly as we have optimized the constituent designs of the major subsystems, i.e. the fiber system, the telescope interface, the calibration system and the spectrograph itself. These modifications have been made to enhance G-CLEF's capability to address frontier science problems, as well as to respond to the evolution of the GMT itself and developments in the technical landscape. G-CLEF has been designed by applying rigorous systems engineering methodology to flow Level 1 Scientific Objectives to Level 2 Observational Requirements and thence to Level 3 and Level 4. The rigorous systems approach applied to G-CLEF establishes a well defined science requirements framework for the engineering design. By adopting this formalism, we may flexibly update and analyze the capability of G-CLEF to respond to new scientific discoveries as we move toward first light. G-CLEF will exploit numerous technological advances and features of the GMT itself to deliver an efficient, high performance instrument, e.g. exploiting the adaptive optics secondary system to increase both throughput and radial velocity measurement precision.

VizieR Online Data Catalog: Abundances in the local region. I. G and K giants (Luck, 2015)

NASA Astrophysics Data System (ADS)

Luck, R. E.

2015-10-01

At the start of this program, the observation list for giants was set to sample the G/K giants of the local region out to about 100pc from the Sun in all directions. The region was subdivided into cubes that were 25pc on a side; from each sub-volume, appropriate stars were selected north of declination -30°. This sample yielded the 286 G/K giants found in Luck et al. 2007 (cat. J/AJ/133/2464). This data set was also augmented by the addition of numerous G/K giants, increasing the number in the 100pc volume to 594 stars. Because the volume selection criteria used in Luck et al. 2007 (cat. J/AJ/133/2464) formally extended out to 115pc, a more precise comparison is that the current sample has 740 stars out to the older limit. Additional stars from the Bright Star Catalog (Hoffleit & Jaschek, 1991bsc..book.....H) were added, driving the sample out to about 200pc. The spectral database was supplemented using the ELODIE and ESO Archives. The ESO addition adds the southern sky. The bulk of the northern stars were observed using the McDonald Observatory Struve Telescope and Sandiford Cassegrain Echelle Spectrograph. For the ELODIE and ESO data archives, a list of all stars available was obtained and spectral type for each from SIMBAD was retrieved. Stars having a spectral type of F, G, or K III were then processed. The ESO data derives from the HARPS and UVES spectrographs. Basic observational data for the program stars can be found in Table1, along with some derived quantities, such as distance. The primary source of observational data for this study is a set of high signal-to-noise ratio (S/N) spectra obtained during numerous observing runs between 1997 and 2010 at McDonald Observatory using the 2.1m Struve Telescope and the Sandiford Cassegrain Echelle Spectrograph. The spectra continuously cover a wavelength range from about 484 to 700nm, with a resolving power of about 60000. Typical S/N values for the spectra are in excess of 150. To enable cancellation of telluric lines, broad-lined B stars were regularly observed with S/N exceeding that of the program stars. The 726 stars observed with the Sandiford spectrograph are marked with an "S" in column "Sce" of Table1. A further 120 spectra were obtained from the ELODIE Archive. These echelle spectra are fully processed through order co-addition with a continuous wavelength span from about 400 to 680 nm and a resolution of 42000. Only spectra with S/N>50 were utilized in this analysis. An "E" in Table1, column "Sce", marks these stars. The ESO Archive was used to obtain spectra from the ESO 3.6m telescope and HARPS spectrograph. The HARPS spectra cover a continuous wavelength range from about 400 to 680nm with a native resolving power of 120000. To match the resolution of the Sandiford data and to increase the S/N of the data, these spectra were co-added to a resolution of 60000. Typical maximum S/N values (per pixel) for the spectra are in excess of 150. In Table1, column "Sce", these stars are marked with an "H." Spectra from the UVES spectrograph and VLT/UT2 were also utilized. These spectra are rather heterogeneous, having resolutions of 40000-80000 and non-continuous spectral coverages in the range 400-700nm. A number of the spectra from UVES stop at about 625nm, meaning that [O I] 630nm and Li I 670nm were not observed. In Table 1, "U" denotes the stars observed with UVES spectrograph. (5 data files).

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).

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;

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).

Spectroscopic Instrumentation in Undergraduate Astronomy Laboratories

NASA Astrophysics Data System (ADS)

Ludovici, Dominic; Mutel, Robert Lucien; Lang, Cornelia C.

2017-01-01

We have designed and built two spectrographs for use in undergraduate astronomy laboratories at the University of Iowa. The first, a low cost (appx. $500) low resolution (R ~ 150 - 300) grating-prism (grism) spectrometer consists of five optical elements and is easily modified to other telescope optics. The grism spectrometer is designed to be used in a modified filter wheel. This type of spectrometer allows students to undertake projects requiring sensitive spectral measurements, such as determining the redshifts of quasars. The second instrument is a high resolution (R ~ 8000), moderate cost (appx. $5000) fiber fed echelle spectrometer. The echelle spectrometer will allow students to conduct Doppler measurements such as those used to study spectroscopic binaries. Both systems are designed to be used with robotic telescope systems. The availability of 3D printing enables both of these spectrographs to be constructed in hands-on instrumentation courses where students build and commission their own instruments. Additionally, these instruments enable introductory majors and non-majors laboratory students to gain experience conducting their own spectroscopic observations.

Spectroscopic monitoring of bright A-F type candidate hybrid stars discovered by the Kepler mission

NASA Astrophysics Data System (ADS)

Lampens, Patricia; Frémat, Y.; Vermeylen, Lore; De Cat, Peter; Dumortier, Louis; Sódor, Ádám; Sharka, Marek; Bognár, Zsófia

2018-04-01

We report on a study of 250 optical spectra for 50 bright A/F-type candidate hybrid pulsating stars from the Kepler field. Most of the spectra have been collected with the high-resolution spectrograph HERMES attached to the Mercator telescope, La Palma. We determined the radial velocities (RVs), projected rotational velocities, fundamental atmospheric parameters and provide a classification based on the appearance of the cross-correlation profiles and the behaviour of the RVs with time in order to find true hybrid pulsators. Additionally, we also detected new spectroscopic binary and multiple systems in our sample and determined the fraction of spectroscopic systems. In order to be able to extend this investigation to the fainter A-F type candidate hybrid stars, various high-quality spectra collected with 3-4 m sized telescopes suitably equipped with a high-resolution spectrograph and furthermore located in the Northern hemisphere would be ideal. This programme could be done using the new instruments installed at the Devasthal Observatory.

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).

Atomic Physics with the Goddard High Resolution Spectrograph on the Hubble Space Telescope. III; Oscillator Strengths for Neutral Carbon

NASA Technical Reports Server (NTRS)

Zsargo, J.; Federman, S. R.; Cardelli, Jason A.

1997-01-01

High quality spectra of interstellar absorption from C I toward beta(sup 1) S(sub co), rho O(sub ph) A, and chi O(sub ph) were obtained with the Goddard High Resolution Spectrograph on HST. Many weak lines were detected within the observed wavelength intervals: 1150-1200 A for beta(sup 1) S(sub co) and 1250-1290 A for rho O(sub ph) A and chi O(sub ph). Curve-of-growth analyses were performed in order to extract accurate column densities and Doppler parameters from lines with precise laboratory-based f-values. These column densities and b-values were used to obtain a self-consistent set of f-values for all the observed C I lines. A particularly important constraint was the need to reproduce data for more than one line of sight. For about 50% of the lines, the derived f-values differ appreciably from the values quoted by Morton.

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.

Design progress of the solar UV-Vis-IR telescope (SUVIT) aboard SOLAR-C

NASA Astrophysics Data System (ADS)

Katsukawa, Y.; Ichimoto, K.; Suematsu, Y.; Hara, H.; Kano, R.; Shimizu, T.; Matsuzaki, K.

2013-09-01

We present a design progress of the Solar UV-Vis-IR Telescope (SUVIT) aboard the next Japanese solar mission SOLAR-C. SUVIT has an aperture diameter of ~1.4 m for achieving spectro-polarimetric observations with spatial and temporal resolution exceeding the Hinode Solar Optical Telescope (SOT). We have studied structural and thermal designs of the optical telescope as well as the optical interface between the telescope and the focal plane instruments. The focal plane instruments are installed into two packages, filtergraph and spectrograph packages. The spectropolarimeter is the instrument dedicated to accurate polarimetry in the three spectrum windows at 525 nm, 854 nm, and 1083 nm for observing magnetic fields at both the photospheric and chromospheric layers. We made optical design of the spectrograph accommodating the conventional slit spectrograph and the integral field unit (IFU) for two-dimensional coverage. We are running feasibility study of the IFU using fiber arrays consisting of rectangular cores.

VizieR Online Data Catalog: Radial velocities of δ Sagittae (Pugh+, 2015)

NASA Astrophysics Data System (ADS)

Pugh, T.; Gray, D. F.; Griffin, R. F.

2018-01-01

28 spectra were obtained by Gray and Pugh between 2008 July and 2010 October (MJD 2454674-2455479) with the high-resolution (R~100000) coude spectrograph of the Elginfield Observatory of Western University (Gray 2009ApJ...697.1032G). The signal-to-noise ratios in the continuum, estimated from the photon counts, ranged from 152 to 314 with a mean of 220. The spectrograph has a dispersion of ~0.013 Å/mm and can reach a radial-velocity precision of 25 m/s by reference to water vapour lines inside the spectrograph (Gray & Brown 2006PASP..118.1112G). In the current case our measurement errors (based on exposures taken within a few nights of one another) range from 27 to 160 m/s, with a mean value of 90 m/s. The radial velocities were determined by measuring the positions of the spectral lines at 85 per cent of the line depth for 15 neutral metal lines in the λ6250-Å region. (1 data file).

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).

CARMENES: management of a schedule-driven project

NASA Astrophysics Data System (ADS)

García-Vargas, M. L.; Caballero, J.; Pérez-Calpena, A.; Amado, Pedro; Seifert, Walter; Azzaro, Marco; Mandel, Holger; Quirrenbach, Andreas; Ribas, Ignasi; Reiners, Ansgar; Guenther, Eike; Gesa, Lluís.; Galadí, David; Aceituno, Jesús

2016-08-01

CARMENES (Calar Alto high-Resolution search for M dwarfs with Exoearths with Near-infrared and optical Échelle Spectrographs) is an instrument consistent in two ultra-stable high resolution (R 82,000) spectrographs covering simultaneously the visible (0.5 - 1.0μm) and near-IR (1.0 - 1.7μm) ranges to provide high-accuracy radial-velocity measurements (˜1 m/s) thanks to the long-term stability. CARMENES was the initiative of a consortium of eleven German and Spanish institutions. CARMENES has been built for the 3.5m telescope at the Centro Astronómico Hipano- Alemán (CAHA), Calar Alto Observatory (Almería, Spain) and is currently in operation. CAHA is jointly operated by the Max-Planck-Society (MPG) and the Spanish National Research Council (CSIC). The project received the green light in October 2010 and in February 2013 passed a Final Design Review. Six months later, the MPG and CSIC, the observatory's owners, made an independent evaluation concluding that CARMENES had to be ready for operations at the end of 2015. Since then, fulfilling the calendar was the driver of all project decisions. Moreover, the observatory's survival was linked to the instrument's success: should the instrument fail, the observatory would be closed. On the contrary, the instrument's success would give unique capabilities to the Observatory for Big Science. Such a challenge became to be our private Olympic Games: we had to be on time. This decision definitively impacted on the project dynamics, there was no room for a delay. The deadline, December 31st, 2015, was controlled by a strict tracking of the critical path; calendar deviations were corrected with risky decisions while fast tracking or even crashing methods were applied. The management scenario was far from optimum: most key people in the project shared their time with other duties; the observatory funding cuts; the budget was tight and distributed among the 11 partner centers with their own different rules, etc. Despite these difficulties, the close coordination among the project manager, the system engineer and the work package managers, the hard work of the whole team, and the support from the observatory were our best bets. Two frenetic years after the calendar decision, we had manufactured, integrated and tested the two spectrographs and we were commissioning the instrument. The instrument first light took place on November, 9th, 2015 and CARMENES entered in operation at the end of December 2015. This paper describes the keys to success.

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.

New Window on the Universe.

ERIC Educational Resources Information Center

Reynolds, Ronald F.

1984-01-01

Describes the basic components of a space telescope that will be launched during a 1986 space shuttle mission. These components include a wide field/planetary camera, faint object spectroscope, high-resolution spectrograph, high-speed photometer, faint object camera, and fine guidance sensors. Data to be collected from these instruments are…

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.

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.

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.

High-efficiency in situ resonant inelastic x-ray scattering (iRIXS) endstation at the Advanced Light Source

DOE PAGES

Qiao, Ruimin; Li, Qinghao; Zhuo, Zengqing; ...

2017-03-17

In this paper, an endstation with two high-efficiency soft x-ray spectrographs was developed at Beamline 8.0.1 of the Advanced Light Source, Lawrence Berkeley National Laboratory. The endstation is capable of performing soft x-ray absorption spectroscopy, emission spectroscopy, and, in particular, resonant inelastic soft x-ray scattering (RIXS). Two slit-less variable line-spacing grating spectrographs are installed at different detection geometries. The endstation covers the photon energy range from 80 to 1500 eV. For studying transition-metal oxides, the large detection energy window allows a simultaneous collection of x-ray emission spectra with energies ranging from the O K-edge to the Ni L-edge without movingmore » any mechanical components. The record-high efficiency enables the recording of comprehensive two-dimensional RIXS maps with good statistics within a short acquisition time. By virtue of the large energy window and high throughput of the spectrographs, partial fluorescence yield and inverse partial fluorescence yield signals could be obtained for all transition metal L-edges including Mn. Finally and moreover, the different geometries of these two spectrographs (parallel and perpendicular to the horizontal polarization of the beamline) provide contrasts in RIXS features with two different momentum transfers.« less

An infrared high resolution silicon immersion grating spectrometer for airborne and space missions

NASA Astrophysics Data System (ADS)

Ge, Jian; Zhao, Bo; Powell, Scott; Jiang, Peng; Uzakbaiuly, Berik; Tanner, David

2014-08-01

Broad-band infrared (IR) spectroscopy, especially at high spectral resolution, is a largely unexplored area for the far IR (FIR) and submm wavelength region due to the lack of proper grating technology to produce high resolution within the very constrained volume and weight required for space mission instruments. High resolution FIR spectroscopy is an essential tool to resolve many atomic and molecular lines to measure physical and chemical conditions and processes in the environments where galaxy, star and planets form. A silicon immersion grating (SIG), due to its over three times high dispersion over a traditional reflective grating, offers a compact and low cost design of new generation IR high resolution spectrographs for space missions. A prototype SIG high resolution spectrograph, called Florida IR Silicon immersion grating spectromeTer (FIRST), has been developed at UF and was commissioned at a 2 meter robotic telescope at Fairborn Observatory in Arizona. The SIG with 54.74 degree blaze angle, 16.1 l/mm groove density, and 50x86 mm2 grating area has produced R=50,000 in FIRST. The 1.4-1.8 um wavelength region is completely covered in a single exposure with a 2kx2k H2RG IR array. The on-sky performance meets the science requirements for ground-based high resolution spectroscopy. Further studies show that this kind of SIG spectrometer with an airborne 2m class telescope such as SOFIA can offer highly sensitive spectroscopy with R~20,000-30,000 at 20 to 55 microns. Details about the on-sky measurement performance of the FIRST prototype SIG spectrometer and its predicted performance with the SOFIA 2.4m telescope are introduced.

Chromospheric Heating Driven by Cancellations of Internetwork Magnetic Flux

NASA Astrophysics Data System (ADS)

Gosic, M.; de la Cruz Rodriguez, J.; De Pontieu, B.; Bellot Rubio, L.; Esteban Pozuelo, S.; Ortiz-Carbonell, A. N.

2017-12-01

The heating of the solar chromosphere remains to be one of the most important questions in solar physics. It is believed that this phenomenon may significantly be supported by small-scale internetwork (IN) magnetic fields. Indeed, cancellations of IN magnetic flux can generate transient brightenings in the chromosphere and transition region. These bright structures might be the signature of energy release and plasma heating, probably driven by magnetic reconnection of IN field lines. Using high resolution, multiwavelength, coordinated observations recorded with the Interface Region Imaging Spectrograph (IRIS) and the Swedish 1-m Solar Telescope (SST), we analyzed cancellations of IN flux and their impact on the energetics and dynamics of the quiet Sun atmosphere. From their temporal and spatial evolution, we determine that these events can heat locally the upper atmospheric layers. However, employing multi-line inversions of the Mg II h & k lines, we show that cancellations, although occurring ubiquitously over IN regions, are not capable of sustaining the total radiative losses of the quiet Sun chromosphere.

TESS Follow-up Observing Programs at the University of Wyoming

NASA Astrophysics Data System (ADS)

Jang-Condell, Hannah; Kasper, David; Kar, Aman; Sorber, Rebecca; Hancock, Daniel A.; Leuquire, Jacob D.; Suhaimi, Afiq; Kobulnicky, Henry A.; Pierce, Michael; Pilachowski, Catherine A.

2018-06-01

The Transiting Exoplanet Survey Satellite (TESS), launched in Spring 2018, will detect thousands of new exoplanet candidates. These candidates will need to be vetted by ground-based observatories to rule out false positives. The Observatories at the University of Wyoming are well-positioned to take active roles in TESS Follow-Up Observing Program (TFOP) Working Groups. The 0.6-m Red Buttes Observatory has already demonstrated its capability to do precision photometric monitoring of transiting exoplanet targets as a participant in the Kilodegree Extremely Little Telescope Follow-Up Network (KELT-FUN). A new echelle spectrograph, Fiber High-Resolution Echelle (FHiRE), being built for the 2.3-m Wyoming InfraRed Observatory (WIRO), will enable precision radial velocity measurements of exoplanet candidates. Over 180 nights/year at both observatories will be available to our team to undertake follow-up observations of TESS Objects of Interest (TOIs). We anticipate making significant contributions to new exoplanet discoveries in the era of TESS.

Preliminary results on the various U.V. straylight sources for the VWFC onboard SL 1. [Very Wide Field Camera

NASA Technical Reports Server (NTRS)

Viton, M.; Courtes, G.; Sivan, J. P.; Decher, R.; Gary, A.

1985-01-01

Technical difficulties encountered using the Very Wide Field Camera (VWFC) during the Spacelab 1 Shuttle mission are reported. The VWFC is a wide low resolution (5 arcmin half-half width) photographic camera, capable of operating in both spectrometric and photometric modes. The bandpasses of the photometric mode of the VWFC are defined by three Al + MgF2 interference filters. A piggy-back spectrograph attached to the VWFC was used for observations in the spectrometric mode. A total of 48 astronomical frames were obtained using the VWFC, of which only 20 were considered to be of adequate quality for astronomical data processing. Preliminary analysis of the 28 poor-quality images revealed the following possible defects in the VWFC: darkness in the spacing frames, twilight/dawn UV straylight, and internal UV straylight. Improvements in the VWFC astronomical data processing scheme are expected to help identify and eliminate UV straylight sources in the future.

A decade of astrocombs: recent advances in frequency combs for astronomy.

PubMed

McCracken, Richard A; Charsley, Jake M; Reid, Derryck T

2017-06-26

A new regime of precision radial-velocity measurements in the search for Earth-like exoplanets is being facilitated by high-resolution spectrographs calibrated by laser frequency combs. Here we review recent advances in the development of astrocomb technology, and discuss the state of the field going forward.

On the design of the PEPSI spectropolarimeter for the LBT

NASA Astrophysics Data System (ADS)

Ilyin, I.; Strassmeier, K. G.; Woche, M.; Dionies, F.; Di Varano, I.

2011-10-01

We present the design concept of the spectropolarimeter for the high-resolution echelle spectrograph PEPSI to be installed at the 2×8.4 m Large Binocular Telescope (LBT) in Arizona. We discuss the optical key elements, the principles of operations of the instrument and its instrumental polarization effects.

The O IV and S IV intercombination lines in solar and stellar ultraviolet spectra

NASA Technical Reports Server (NTRS)

Cook, J. W.; Keenan, F. P.; Dufton, P. L.; Kingston, A. E.; Pradhan, A. K.; Zhang, H. L.; Doyle, J. G.; Hayes, M. A.

1995-01-01

New calculations of O IV electron density diagnostic emission-line ratios involving the 1399.8, 1401.2, 1404.8, and 14076.4 A transitions are presented. A comparison of these calculations with observational data from a quiet solar region, a sunspot, and an active region obtained with the High Resolution Telescope and Spectrograph (HRTS), two flares observed with the SO82B spectrograph on board Skylab, and Hubble Space Telescope (HST) observations by the Goddard High Resolution Spectrograph (GHRS) of Capella, gives good results using the ratio R(sub 1) = I(1407.4 A)/I(1401.2 A). However, the electron density obtained using the ratio R(sub 2) = I(1407.4 A)/I(1404.8 A) is often an order of magnitude smaller. The O IV 1404.8 A line is blended with the S IV 1404.8 A line, and we investigate whether this ratio may still be used as a density diagnostic if the S IV 1406.1 A line intensity is used to correct for the presence of S IV 1404.8 A, using previous S IV calculations by Dufton et al. We still find systematic differences compared to density determinations from line ratios that do not involve the O IV 1404.8 A line, which we suggest are due to errors in earlier theoretical calculations of the S IV atomic data, and also possibly to previously unconsidered fluorescent pumping of the upper level of the S IV 1404.8 A transition.

Fluorescence/depolarization lidar for mid-range stand-off detection of biological agents

NASA Astrophysics Data System (ADS)

Mierczyk, Z.; Kopczyński, K.; Zygmunt, M.; Wojtanowski, J.; Młynczak, J.; Gawlikowski, A.; Młodzianko, A.; Piotrowski, W.; Gietka, A.; Knysak, P.; Drozd, T.; Muzal, M.; Kaszczuk, M.; Ostrowski, R.; Jakubaszek, M.

2011-06-01

LIDAR system for real-time standoff detection of bio-agents is presented and preliminary experimental results are discussed. The detection approach is based on two independent physical phenomena: (1) laser induced fluorescence (LIF), (2) depolarization resulting from elastic scattering on non-spherical particles. The device includes three laser sources, two receiving telescopes, depolarization component and spectral signature analyzing spectrograph. It was designed to provide the stand-off detection capability at ranges from 200 m up to several kilometers. The system as a whole forms a mobile platform for vehicle or building installation. Additionally, it's combined with a scanning mechanics and advanced software, which enable to conduct the semi-automatic monitoring of a specified space sector. For fluorescence excitation, 3-rd (355 nm) and 4-th (266 nm) harmonics of Nd:YAG pulsed lasers are used. They emit short (~6 ns) pulses with the repetition rate of 20 Hz. Collecting optics for fluorescence echo detection and spectral content analysis includes 25 mm diameter f/4 Newton telescope, Czerny Turner spectrograph and 32-channel PMT. Depending on the grating applied, the spectral resolution from 20 nm up to 3 nm per channel can be achieved. The system is also equipped with an eye-safe (1.5 μm) Nd:YAG OPO laser for elastic backscattering/depolarization detection. The optical echo signal is collected by Cassegrain telescope with aperture diameter of 12.5 mm. Depolarization detection component based on polarizing beam-splitter serves as the stand-off particle-shape analyzer, which is very valuable in case of non-spherical bio-aerosols sensing.

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.

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.

Performance Results from In-Flight Commissioning of the Juno Ultraviolet Spectrograph (Juno-UVS)

NASA Astrophysics Data System (ADS)

Greathouse, Thomas K.; Gladstone, G. R.; Davis, M. W.; Slater, D. C.; Versteeg, M. H.; Persson, K. B.; Winters, G. S.; Persyn, S. C.; Eterno, J. S.

2012-10-01

We present a description of the Juno ultraviolet spectrograph (Juno-UVS), results from the successful in-flight commissioning performed between December 5th and 13th 2011, and some predictions of future Jupiter observations. 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 rotationally stabilized spacecraft. The planned 2 rpm rotation rate for the primary mission results in integration times per spatial resolution element per spin of only 17 ms. Thus, data was retrieved from many spins and then remapped and co-added to build up integration times on bright stars to measure the effective area, spatial resolution, map out scan mirror pointing positions, etc. 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. We will describe our process for solving for the pointing of the scan mirror relative to the Juno spacecraft and present our initial half sky survey of UV bright stars complete with constellation overlays. 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 facilitate these measurements, allowing Juno-UVS to observe the surface positions of magnetic field lines Juno is flying through giving a direct connection between the particle measurements on the spacecraft to the observed reaction of Jupiter’s atmosphere to those particles. Finally, we will describe planned observations to be made during Earth flyby in October 2013 that will complete the in-flight characterization.

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.

Science Objectives of EOS-Aura's Ozone Monitoring Instrument (OMI)

NASA Technical Reports Server (NTRS)

Levelt, P. F.; Veefkind, J. P.; Stammes, P.; Hilsenrath, E.; Bhartia, P. K.; Chance, K. V.; Leppelmeier, G. W.; Maelkki, A.; Bhartia, Pawan (Technical Monitor)

2002-01-01

OMI is a UV/VIS nadir solar backscatter spectrograph, which provides near global coverage in one day with a spatial resolution of 13 x 24 sq km. OMI is a new instrument, with a heritage from the European satellite instruments GOME, GOMOS and SCIAMACHY. OMI's unique capabilities for measuring important trace gases with a small footprint and daily global coverage, in conjunction with the other Aura instruments, will make a major contribution to our understanding of stratospheric and tropospheric chemistry and climate change. OMI will measure solar irradiance and Earth radiances in the wavelength range of 270 to 500 nm with spectral resolution of about 0.5 nm and a spectral sampling of about 2-3 per FWHM. From these observations, total columns of O3, NO2, BrO and SO2 will be derived from the back-scattered solar radiance using differential absorption spectroscopy (DOAS). The TOMS total ozone record will also be continued by employing the well established TOMS algorithm. Because of the high accuracy and spatial resolution of the measurements, a good estimate of tropospheric amounts of ozone and NO2 are expected. Ozone profiles will be derived using the optimal estimation method. The spectral aerosol optical depth will be determined from measurements between 340 and 500 nm. This will provide information on aerosol concentration, aerosol size distribution and aerosol type. This wavelength range makes it possible to retrieve aerosol information over both land and sea. OMI observations will also allow retrievals of cloud coverage and cloud heights. From these products, the UV-B flux at the surface can then be derived with high spatial resolution.

History of Hubble Space Telescope (HST)

NASA Image and Video Library

1981-01-01

This drawing illustrates the Hubble Space Telescope's (HST's), Goddard High-Resolution Spectrograph (GHRS). The HST's two spectrographs, the GHRS and the Faint Object Spectrograph (FOS), can detect a broader range of wavelengths than is possible from 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 GHRS can detect fine details in the light from somewhat brighter objects but only ultraviolet light. 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.

History of Hubble Space Telescope (HST)

NASA Image and Video Library

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.

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.

2dF mechanical engineering

NASA Astrophysics Data System (ADS)

Smith, Greg; Lankshear, Allan

1998-07-01

2dF is a multi-object instrument mounted at prime focus at the AAT capable of spectroscopic analysis of 400 objects in a single 2 degree field. It also prepares a second 2 degree 400 object field while the first field is being observed. At its heart is a high precision robotic positioner that places individual fiber end magnetic buttons on one of two field plates. The button gripper is carried on orthogonal gantries powered by linear synchronous motors and contains a TV camera which precisely locates backlit buttons to allow placement in user defined locations to 10 (mu) accuracy. Fiducial points on both plates can also be observed by the camera to allow repeated checks on positioning accuracy. Field plates rotate to follow apparent sky rotation. The spectrographs both analyze light from the 200 observing fibers each and back- illuminate the 400 fibers being re-positioned during the observing run. The 2dF fiber position and spectrograph system is a large and complex instrument located at the prime focus of the Anglo Australian Telescope. The mechanical design has departed somewhat from the earlier concepts of Gray et al, but still reflects the audacity of those first ideas. The positioner is capable of positioning 400 fibers on a field plate while another 400 fibers on another plate are observing at the focus of the telescope and feeding the twin spectrographs. When first proposed it must have seemed like ingenuity unfettered by caution. Yet now it works, and works wonderfully well. 2dF is a system which functions as the result of the combined and coordinated efforts of the astronomers, the mechanical designers and tradespeople, the electronic designers, the programmers, the support staff at the telescope, and the manufacturing subcontractors. The mechanical design of the 2dF positioner and spectrographs was carried out by the mechanical engineering staff of the AAO and the majority of the manufacture was carried out in the AAO workshops.

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.

VizieR Online Data Catalog: Abundances of LAMOST giants from APOGEE DR12 (Ho+, 2017)

NASA Astrophysics Data System (ADS)

Ho, A. Y. Q.; Ness, M. K.; Hogg, D. W.; Rix, H.-W.; Liu, C.; Yang, F.; Zhang, Y.; Hou, Y.; Wang, Y.

2017-09-01

The Large sky Area Multi-Object Spectroscopic Telescope (LAMOST) is a low-resolution (R~1800) optical (3650-9000Å) spectroscopic survey. APOGEE is a high-resolution (R~22500), high-S/N (S/N~100), H-band (15200-16900Å) spectroscopic survey, part of the Sloan Digital Sky Survey III. Observations are conducted using a 300 fiber spectrograph on the 2.5m Sloan Telescope at the Apache Point Observatory (APO) in Sunspot, New Mexico (USA). (1 data file).

Spectroscopy of the nova candidate M31-2008-10b

NASA Astrophysics Data System (ADS)

Di Mille, F.; Ciroi, S.; Orio, M.; Rafanelli, P.; Bianchini, A.; Nelson, T.; Andreuzzi, G.

2008-10-01

We obtained a low resolution spectrum of the nova candidate M31-2008-10b ( see CBAT M31 nova page) on 2008 October 26.12 UT. The observations were performed with TNG + DOLORES spectrograph 20 days after the first detection (see Atel #1790 ). The spectrum (in the 330-790 nm range, with resolution 1 nm) shows strong Balmer lines superimposed on a flat continuum.

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

NASA Astrophysics Data System (ADS)

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

2018-05-01

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

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;

Space Telescope maintenance and refurbishment

NASA Technical Reports Server (NTRS)

Trucks, H. F.

1983-01-01

The Space Telescope (ST) represents a new concept regarding spaceborne astronomical observatories. Maintenance crews will be brought to the orbital worksite to make repairs and replace scientific instruments. For major overhauls the telescope can be temporarily returned to earth with the aid of the Shuttle. It will, thus, be possible to conduct astronomical studies with the ST for two decades or more. The five first-generation scientific instruments used with the ST include a wide field/planetary camera, a faint object camera, a faint object spectrograph, a high resolution spectrograph, and a high speed photometer. Attention is given to the optical telescope assembly, the support systems module, aspects of mission and science operations, unscheduled maintenance, contingency orbital maintenance, planned on-orbit maintenance, ground maintenance, ground refurbishment, and ground logistics.

Optical Fiber Evaluation for the Hobby-Eberly Telescope

NASA Astrophysics Data System (ADS)

McGouldrick, K.; Maywalt, J.; Engel, L.; Rhoads, B.; Andersen, D. R.; Ramsey, L. W.

1998-12-01

Two major facility instruments on the Hobby-Eberly telescope (HET) are fiber coupled: the high and medium resolution spectrographs. Understanding the behavior of the fibers with the HET is central to understanding the performance of the telescope/spectrograph system. We will describe the Penn State fiber evaluation facility which enables us to measure focal ratio degradation (FRD) and total throughput. We will present some typical data obtained using the HET focal ratio at the fiber input. The HET design has a roving pupil that changes the illumination pattern somewhat during the typical 1 hour tracking time on a target. We will describe our plans to simulate the HET input test the degree to which the varying pupil is scrambled by the fiber.

VizieR Online Data Catalog: HeI 5876 & 10830Å EWs of solar-type stars (Andretta+, 2017)

NASA Astrophysics Data System (ADS)

Andretta, V.; Giampapa, M. S.; Covino, E.; Reiners, A.; Beeck, B.

2017-11-01

A total of 134 FEROS spectra (R=48000) of our targets (including telluric standards) were acquired on the night of UT 2011 December 6-7; spectral coverage from 3500 to 9200Å. The Fiber Extended-range Optical Spectrograph (FEROS) was mounted at the 2.2m Max-Planck Gesellschaft/European Southern Observatory (MPG/ESO) telescope at La Silla (Chile). The HeIλ10830 spectroscopic observations were carried out on the same night as the FEROS D3 observations, using the CRyogenic high-resolution InfraRed Echelle Spectrograph (CRIRES), mounted at Unit Telescope 1 (Antu) of the VLT array at Cerro Paranal. The details of the observations is given in table 1. (3 data files).

Status and Performance Updates for the Cosmic Origins Spectrograph

NASA Astrophysics Data System (ADS)

Snyder, Elaine M.; De Rosa, Gisella; Fischer, William J.; Fix, Mees; Fox, Andrew; Indriolo, Nick; James, Bethan; Oliveira, Cristina M.; Penton, Steven V.; Plesha, Rachel; Rafelski, Marc; Roman-Duval, Julia; Sahnow, David J.; Sankrit, Ravi; Taylor, Joanna M.; White, James

2018-01-01

The Hubble Space Telescope's Cosmic Origins Spectrograph (COS) moved the spectra on the FUV detector from Lifetime Position 3 (LP3) to a new pristine location, LP4, in October 2017. The spectra were shifted in the cross-dispersion direction by -2.5" (roughly -31 pixels) from LP3, or -5" (roughly -62 pixels) from the original LP1. This move mitigates the adverse effects of gain sag on the spectral quality and accuracy of COS FUV observations. Here, we present updates regarding the calibration of FUV data at LP4, including the flat fields, flux calibrations, and spectral resolution. We also present updates on the time-dependent sensitivities and dark rates of both the NUV and FUV detectors.

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.

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;

CARMENES: Commissioning and first scientific results at the telescope. A precursor for HIRES@E-ELT

NASA Astrophysics Data System (ADS)

Amado, P. J.; The Carmenes Consortium

2017-03-01

CARMENES is the next generation instrument built for the CAHA 3.5m telescope by a large international consortium of 11 institutes in Spain and Germany. It consists of two separate highly-stabilized, high-resolution echelle spectrographs covering both the visible, from 550 to 950 nm, and the near-IR, from 950 to 1700 nm, wavelength ranges with spectral resolution of R=82,000. They are fed by fibres from the Cassegrain focus of the telescope and were designed and built to achieve high-accuracy radial velocities of nearby M-dwarf stars. This contribution overviews the main and unique design characteristics of CARMENES. The instrument MAIV phase was achieved in the last two years (2014-2015) and started commissioning in November 2015. The commissioning phases, both technical and scientific, took six full weeks in the last two months of 2015. They have shown that the instrument is well within requirements and performing to be able to achieve its objective, not proven before in the near-infrared, of providing radial velocities precisions of 5 ms^{-1}, with a goal of 1 ms^{-1}. The Guaranteed Time Observations (GTO) program has started in January 1st, 2016. CARMENES is, therefore, currently conducting a radial-velocity survey of 300 M dwarfs with a precision sufficient for detecting Earth-like planets in their habitable zones. It is also being offered in open time by the CAHA. Its modular design is the idea in which HIRES, the next very high-resolution, high-fidelity spectrograph with wide wavelength coverage at the E-ELT, is based on. This E-ELT instrument might consist of four different high-resolution spectrographs covering the blue, the visible, the near-infrared (Y, J and H bands) and the K band. A proposal to the ESO call for Phase-A studies for a HIRES at the E-ELT was submitted by the HIRES consortium last December. This proposal was accepted by ESO and the Phase-A kick-off meeting between ESO and the consortium took place in March 22, 2016.

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).

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.

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 "

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).

Last technology and results from the IOTA interferometer

NASA Astrophysics Data System (ADS)

Pedretti, Ettore; Traub, Wesley A.; Monnier, John D.; Schuller, Peter A.; Ragland, Sam; Berger, Jean–Philippe; Millan-Gabet, Rafael; Wallace, Gary; Burke, Michael; Lacasse, Marc G.; Thureau, Nathalie D.; Carleton, Nathaniel

2008-07-01

The infrared optical telescope array (IOTA), one of the most productive interferometers in term of science and new technologies was decommissioned in summer 2006. We discuss the testing of a low-resolution spectrograph coupled with the IOTA-3T integrated-optics beam combiner and some of the scientific results obtained from this instrument.

VizieR Online Data Catalog: SAMI Galaxy Survey: rotators classification (van de Sande+, 2017)

NASA Astrophysics Data System (ADS)

van de Sande, J.; Bland-Hawthorn, J.; Fogarty, L. M. R.; Cortese, L.; D'Eugenio, F.; Croom, S. M.; Scott, N.; Allen, J. T.; Brough, S.; Bryant, J. J.; Cecil, G.; Colless, M.; Couch, W. J.; Davies, R.; Elahi, P. J.; Foster, C.; Goldstein, G.; Goodwin, M.; Groves, B.; Ho, I.-T.; Jeong, H.; Jones, D. H.; Konstantopoulos, I. S.; Lawrence, J. S.; Leslie, S. K.; Lopez-Sanchez, A. R.; McDermid, R. M.; McElroy, R.; Medling, A. M.; Oh, S.; Owers, M. S.; Richards, S. N.; Schaefer, A. L.; Sharp, R.; Sweet, S. M.; Taranu, D.; Tonini, C.; Walcher, C. J.; Yi, S. K.

2017-08-01

The SAMI instrument and Galaxy Survey is described in detail in Croom+ (2012MNRAS.421..872C) and Bryant+ (2015MNRAS.447.2857B). SAMI is a multi-object integral field spectrograph on the 3.9m Anglo Australian Telescope (AAT). For the SAMI Galaxy Survey, the 580V grating is used in the blue arm of the spectrograph, which results in a resolution of R~1700 with wavelength coverage of 3700-5700Å. In the red arm, the higher resolution grating 1000R is used, which gives an R~4500 over the range 6300-7400Å. We use 24 unsaturated, unblended CuAr arc lines in the blue arm, and 12 lines in the red arm, from 16 frames between 2013 March 05 and 2015 August 17, for all 819 fibers. The survey has four volume-limited galaxy samples derived from cuts in stellar mass in the Galaxy and Mass Assembly (GAMA) G09, G12, and G15 regions (Driver+ 2011, J/MNRAS/413/971). (2 data files).

Slaying Hydra: A Python-Based Reduction Pipeline for the Hydra Multi-Object Spectrograph

NASA Astrophysics Data System (ADS)

Seifert, Richard; Mann, Andrew

2018-01-01

We present a Python-based data reduction pipeline for the Hydra Multi-Object Spectrograph on the WIYN 3.5 m telescope, an instrument which enables simultaneous spectroscopy of up to 93 targets. The reduction steps carried out include flat-fielding, dynamic fiber tracing, wavelength calibration, optimal fiber extraction, and sky subtraction. The pipeline also supports the use of sky lines to correct for zero-point offsets between fibers. To account for the moving parts on the instrument and telescope, fiber positions and wavelength solutions are derived in real-time for each dataset. The end result is a one-dimensional spectrum for each target fiber. Quick and fully automated, the pipeline enables on-the-fly reduction while observing, and has been known to outperform the IRAF pipeline by more accurately reproducing known RVs. While Hydra has many configurations in both high- and low-resolution, the pipeline was developed and tested with only one high-resolution mode. In the future we plan to expand the pipeline to work in most commonly used modes.

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.

New developments in instrumentation at the W. M. Keck Observatory

NASA Astrophysics Data System (ADS)

Adkins, Sean M.; Armandroff, Taft E.; Fitzgerald, Michael P.; Johnson, James; Larkin, James E.; Lewis, Hilton A.; Martin, Christopher; Matthews, Keith Y.; Prochaska, J. X.; Wizinowich, Peter

2014-07-01

The W. M. Keck Observatory continues to develop new capabilities in support of our science driven strategic plan which emphasizes leadership in key areas of observational astronomy. This leadership is a key component of the scientific productivity of our observing community and depends on our ability to develop new instrumentation, upgrades to existing instrumentation, and upgrades to supporting infrastructure at the observatory. In this paper we describe the as measured performance of projects completed in 2014 and the expected performance of projects currently in the development or construction phases. Projects reaching completion in 2014 include a near-IR tip/tilt sensor for the Keck I adaptive optics system, a new center launch system for the Keck II laser guide star facility, and NIRES, a near-IR Echelle spectrograph for the Keck II telescope. Projects in development include a new seeing limited integral field spectrograph for the visible wavelength range called the Keck Cosmic Web Imager, a deployable tertiary mirror for the Keck I telescope, upgrades to the spectrograph detector and the imager of the OSIRIS instrument, and an upgrade to the telescope control systems on both Keck telescopes.

Coronagraphic Imaging with HST and STIS

NASA Technical Reports Server (NTRS)

Grady, C. A.; Proffitt, C.; Malumuth, E.; Woodgate, B. E.; Gull, T. R.; Bowers, C. W.; Heap, S. R.; Kimble, R. A.; Lindler, D.; Plait, P.

2002-01-01

Revealing faint circumstellar nebulosity and faint stellar or substellar companions to bright stars typically requires use of techniques for rejecting the direct, scattered, and diffracted light of the star. One such technique is Lyot coronagraphy. We summarize the performance of the white-light coronagraphic capability of the Space Telescope Imaging spectrograph, on board the Hubble Space Telescope.

Research of X-ray curved crystals analyzer

NASA Astrophysics Data System (ADS)

Xiao, Shali; Xong, Xian-cai; Qian, Jia-yu; Zhong, Xian-xin; Yan, Guo-hong; Liu, Zhong-li; Ding, Yong-kun

2005-08-01

X-ray spectrograph has long been used as a means of diagnosing conditions of laser-produced plasmas, as information concerning both the temperature and density can be extracted from the emitted radiation. For the measurement of X-ray lines in the energy range of 0.6-6 keV, A curved crystal X-ray spectrometer of reflection type elliptical geometry is required. In order to obtain both high resolution and collection efficiency the elliptical geometry is more advantageous than the flat configurations. Elliptical curved crystals spectrograph with a relatively wide spectral range are of particular use for deducing electron temperatures by measurement of the ratios of lines associated with different charge states. Curved crystals analyzer was designed and manufactured for use on an experiment to investigate the properties of laser produced plasmas. The spectrograph has 1350mm focal length and for these measurements, utilized PET, LIF, KAP and MICA crystal bent onto an elliptical substrate. This crystal analyzer covers the Bragg angel range from 30 to 67.5. The analyzer based on elliptically geometrical principle, which has self-focusing characteristics. The experiment was carried out on Shanghai Shengguang-II Facility and aimed to investigate the characteristics of a high density plasma. Experimental results using Curved crystal analyzer are described which show spectrum of Ti, Au laser-plasma. The focusing crystal analyzer clearly gave an increase in sensitivity over a flat crystal. Spectra showing the main resonance line were recorded with X-ray CCD and with laser energies 150J laser wavelength 350nm. The calculated wavelength resolution is about 500-1000.

The Cosmic Origins Spectrograph

NASA Technical Reports Server (NTRS)

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;

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.

Opportunities for in-depth compositional studies of comets: Summary from semester 2017A observations and prospects for a 2018 observing campaign

NASA Astrophysics Data System (ADS)

DiSanti, Michael A.; Dello Russo, Neil; Bonev, Boncho P.; Gibb, Erika L.; Roth, Nathan; Vervack, Ronald J.; McKay, Adam J.; Kawakita, Hideyo; Cochran, Anita L.

2017-10-01

The period from late 2016 to mid 2017 provided unusually rich observational opportunities for compositional studies of comets using ground-based IR and optical spectroscopy. Three ecliptic comets - Jupiter-family comet (JFC) 45P/Honda-Mrkos-Pajdusakova, JFC 41P/Tuttle-Giacobini-Kresak, and 2P/Encke - as well as two moderately bright nearly istotropic comets from the Oort cloud (C/2015 ER61 PanSTARRS and C/2015 V2 Johnson) experienced highly favorable appritions.In the IR, very long on-source integration times were accumulated on all targets, primarily with the powerful new high-resolution, cross-dispersed iSHELL spectrograph at the IRTF (Rayner et al. 2016 SPIE 9908:1) but also with NIRSPEC at Keck II. This enabled accurate production rates and abundance ratios for 8-10 native ices, and spatially resolved studies of coma physics (H2O rotational temperatures and column abundances). The recent availability of iSHELL coupled with the daytime observing capability at the IRTF has opened a powerful window for conducting detailed compositional studies of comets over a range of heliocentric distances (Rh), particularly at small Rh where studies are relatively sparse. Our campaign provided detections of (or stringent abundance limits for) hyper-volatiles CO and CH4, which are severely lacking in compositional studies of JFCs.For all of these targets, optical spectra measured photo-dissociation product species using the Tull Coude spectrograph at McDonald Observatory, and ARCES at Apache Point Observatory. When possible optical and IR observations were obtained contemporaneously, with the goal of addressing potential parent-product relationships.We summarize our campaign and highlight related presentations. Prospects for investigations during the upcoming favorable apparitions of JFCs 21P/Giacobini-Zinner and 46P/Wirtanen will also be discussed, along with increased capabilities for serial studies (i.e., measurements at multiple Rh) of newly discovered (Oort cloud) comets.This work is supported through the NASA Planetary Atmospheres, Planetary Astronomy, and Astrobiology Programs, the NSF Solar and Planetary Research Program, the NASA-Postdoctoral Program, and the NASA Earth and Space Science Fellowship Program.

New high spectral resolution spectrograph and mid-IR camera for the NASA Infrared Telescope Facility

NASA Astrophysics Data System (ADS)

Tokunaga, Alan T.; Bus, Schelte J.; Connelley, Michael; Rayner, John

2016-10-01

The NASA Infrared Telescope Facility (IRTF) is a 3.0 m infrared telescope located at an altitude of 4.2 km near the summit of Mauna Kea on the island of Hawaii. The IRTF was established by NASA to support planetary science missions. We show new observational capabilities resulting from the completion of iSHELL, a 1-5 μm echelle spectrograph with resolving power of 70,000 using a 0.375 arcsec slit. This instrument will be commissioned starting in August 2016. The spectral grasp of iSHELL is enormous due to the cross-dispersed design and use of a 2Kx2K HgCdTe array. Raw fits files will be publicly archived, allowing for more effective use of the large amount of spectral data that will be collected. The preliminary observing manual for iSHELL, containing the instrument description, observing procedures and estimates of sensitivity can be downloaded at http://irtfweb.ifa.hawaii.edu/~ishell/iSHELL_observing_manual.pdf. This manual and instrument description papers can be downloaded at http://bit.ly/28NFiMj. We are also working to restore to service our 8-25 μm camera, MIRSI. It will be upgraded with a closed cycle cooler that will eliminate the need for liquid helium and allow continuous use of MIRSI on the telescope. This will enable a wider range of Solar System studies at mid-IR wavelengths, with particular focus on thermal observations of NEOs. The MIRSI upgrade includes plans to integrate a visible CCD camera that will provide simultaneous imaging and guiding capabilities. This visible imager will utilize similar hardware and software as the MORIS system on SpeX. The MIRSI upgrade is being done in collaboration with David Trilling (NAU) and Joseph Hora (CfA). For further information on the IRTF and its instruments including visitor instruments, see: http:// irtfweb.ifa.hawaii.edu/. We gratefully acknowledge the support of NASA contract NNH14CK55B, NASA Science Mission Directorate, and NASA grant NNX15AF81G (Trilling, Hora) for the upgrade of MIRSI.

Determining the neutrino mass with cyclotron radiation emission spectroscopy—Project 8

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

Esfahani, Ali Ashtari; Asner, David M.; Böser, Sebastian

The most sensitive direct method to establish the absolute neutrino mass is observation of the endpoint of the tritium beta-decay spectrum. Cyclotron radiation emission spectroscopy (CRES) is a precision spectrographic technique that can probe much of the unexplored neutrino mass range withmore » $${ \\mathcal O }(\\mathrm{eV})$$ resolution. A lower bound of $$m({\

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).

Spectroscopic classification of TCP J17140253-2849233 as a Galactic nova

NASA Astrophysics Data System (ADS)

Williams, S. C.; Darnley, M. J.; Healy, M. W.

2018-03-01

We obtained a spectrum of TCP J17140253-2849233 (see CBAT TOCP, also designated PNV J17140261-2849237) using the FRODOSpec spectrograph (Barnsley et al. 2012) on the 2-m Liverpool Telescope (Steele et al. 2004), with a wavelength coverage of 3900 to 5100 & Aring; and 5900 to 8000 & Aring; and resolution of R 5400.

Determining the neutrino mass with cyclotron radiation emission spectroscopy—Project 8

DOE PAGES

Esfahani, Ali Ashtari; Asner, David M.; Böser, Sebastian; ...

2017-03-30

The most sensitive direct method to establish the absolute neutrino mass is observation of the endpoint of the tritium beta-decay spectrum. Cyclotron radiation emission spectroscopy (CRES) is a precision spectrographic technique that can probe much of the unexplored neutrino mass range withmore » $${ \\mathcal O }(\\mathrm{eV})$$ resolution. A lower bound of $$m({\

The Infrared Spectrograph on the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

Roellig, Thomas L.

2017-01-01

The Infrared Spectrograph (IRS) instrument on the Spitzer Space Telescope covered the 5 to 38 micron wavelength range at low and medium spectral resolutions. The instrument was very popular during Spitzers 5.7 year-long cold mission. Every year it attracted the most proposals, and garnered more observing hours, of any of the science instruments. This success was the culmination of a very long development period, where the instrument design changed radically. When the instrument was first selected by NASA in 1984 it was very complicated. As part of the overall reduction of the size of the SIRTF Observatory following its recovery from the missions cancellation in 1991 the IRS became smaller and much, much simpler. The only aspect of the instrument that increased from the original design was the pixel count of the detectors.

Fiber feed for the CFHT Gecko spectrograph

NASA Astrophysics Data System (ADS)

Baudrand, Jacques; Vitry, Rene

2000-08-01

Motivated by a strong concern to keep maintenance work as low as possible the direction of the CFHT had for some times contemplated the possibility to replace the original mirror train f/20 focus feeding their Gecko High Resolution Coude Spectrograph by a more convenient fiber link coupled to the f/8 Cassegrain focus. A decision supporting that idea was ultimately taken two years ago and our group at the OPM was contacted to build such a system according to precise specifications. This telescope facility, baptized CAFÉ for Cassegrain Fiber Environment, has now arrived to near completion and we are able to present here its main characteristics and the technical solutions that were adopted to meet the CFHT requirements and to provide the system with the best performances in terms of robustness and efficiency.

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).

Spectroscopy of the novae M31N_2008-08a and M31N_2008-08b

NASA Astrophysics Data System (ADS)

Di Mille, F.; Ciroi, S.; Orio, M.; Rafanelli, P.; Bianchini, A.; Nelson, T.; Andreuzzi, G.

2008-09-01

We obtained low resolution spectra of the two optical nova candidates in M31 (see ATEL #1654). The spectra were obtained with the 3.5-m Telescopio Nazionale Galileo of INAF equipped with the DOLORES spectrograph and camera (spectral range 330-790 nm, resolution 1.2 nm) on Aug 17.13 for 2008-08a and on Aug 17.17 for 2008-08b (8 days after the discovery of both novae, which were below the detection limits 2 days earlier).

Absolute spectrophotometry of Titan, Uranus, and Neptune 3500-10,500 A

NASA Technical Reports Server (NTRS)

Neff, J. S.; Humm, D. C.; Bergstralh, J. T.; Cochran, A. L.; Cochran, W. D.; Barker, E. S.; Tull, R. G.

1984-01-01

The present absolute measurements of Titan, Uranus and Neptune geometric albedo spectra in the 3500-10,500 A range have a resolution of about 7 A, together with high SNR, in virtue of the exceptional effeciency of the spectrograph and Reticon detector employed. The high precision and spectral resolution of the data, which are in excellent agreement with the Uranus albedo measurements of Lockwood et al. (1983), make possible quantitative measurements of the effects of Raman scattering by H2 in the Uranus and Neptune atmospheres.

Reconfigurable Pointing Control for High Resolution Space Spectroscopy

NASA Technical Reports Server (NTRS)

Bayard, David S.; Kia, Tooraj; vanCleve, Jeffrey

1997-01-01

In this paper, a pointing control performance criteria is established to support high resolution space spectroscopy. Results indicate that these pointing requirements are very stringent, and would typically be difficult to meet using standard 3-axis spacecraft control. To resolve this difficulty, it is shown that performance can be significantly improved using a reconfigurable control architecture that switches among a small bank of detuned Kalman filters. The effectiveness of the control reconfiguration approach is demonstrated by example on the Space Infra, Red Telescope Facility (SIRTF) pointing system, in support of the Infrared Spectrograph (IRS) payload.

VizieR Online Data Catalog: X-ray AGNs with Subaru/FMOS NIR observations (Suh+, 2015)

NASA Astrophysics Data System (ADS)

Suh, H.; Hasinger, G.; Steinhardt, C.; Silverman, J. D.; Schramm, M.

2016-03-01

We performed NIR spectroscopic observations for the AGN sources with the FMOS high-resolution spectrographs on the Subaru telescope; in J-short (0.92-1.12um), J-long (1.11-1.35um), H-short (1.40-1.60um), and H-long (1.60-1.80um) coverage with a spectral resolution of R~2200. The data span the 2012 Mar 25-2013 Oct 24 period. In addition to NIR spectra, we use existing optical spectroscopy (see section 3.2). (2 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.

Study on a multi-delay spectral interferometry for stellar radial velocity measurement

NASA Astrophysics Data System (ADS)

Zhang, Kai; Jiang, Haijiao; Tang, Jin; Ji, Hangxin; Zhu, Yongtian; Wang, Liang

2014-08-01

High accuracy radial velocity measurement isn't only one of the most important methods for detecting earth-like Exoplanets, but also one of the main developing fields of astronomical observation technologies in future. Externally dispersed interferometry (EDI) generates a kind of particular interference spectrum through combining a fixed-delay interferometer with a medium-resolution spectrograph. It effectively enhances radial velocity measuring accuracy by several times. Another further study on multi-delay interferometry was gradually developed after observation success with only a fixed-delay, and its relative instrumentation makes more impressive performance in near Infrared band. Multi-delay is capable of giving wider coverage from low to high frequency in Fourier field so that gives a higher accuracy in radial velocity measurement. To study on this new technology and verify its feasibility at Guo Shoujing telescope (LAMOST), an experimental instrumentation with single fixed-delay named MESSI has been built and tested at our lab. Another experimental study on multi-delay spectral interferometry given here is being done as well. Basically, this multi-delay experimental system is designed in according to the similar instrument named TEDI at Palomar observatory and the preliminary test result of MESSI. Due to existence of LAMOST spectrograph at lab, a multi-delay interferometer design actually dominates our work. It's generally composed of three parts, respectively science optics, phase-stabilizing optics and delay-calibrating optics. To switch different fixed delays smoothly during observation, the delay-calibrating optics is possibly useful to get high repeatability during switching motion through polychromatic interferometry. Although this metrology is based on white light interferometry in theory, it's different that integrates all of interference signals independently obtained by different monochromatic light in order to avoid dispersion error caused by broad band in big optical path difference (OPD).

MEGARA Optics: Sub-aperture Stitching Interferometry for Large Surfaces

NASA Astrophysics Data System (ADS)

Aguirre-Aguirre, Daniel; Carrasco, Esperanza; Izazaga-Pérez, Rafael; Páez, Gonzalo; Granados-Agustín, Fermín; Percino-Zacarías, Elizabeth; Gil de Paz, Armando; Gallego, Jesús; Iglesias-Páramo, Jorge; Villalobos-Mendoza, Brenda

2018-04-01

In this work, we present a detailed analysis of sub-aperture interferogram stitching software to test circular and elliptical clear apertures with diameters and long axes up to 272 and 180 mm, respectively, from the Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía (MEGARA). MEGARA is a new spectrograph for the Gran Telescopio Canarias (GTC). It offers a resolution between 6000 and 20000 via the use of volume phase holographic gratings. It has an integral field unit and a set of robots for multi-object spectroscopy at the telescope focal plane. The output end of the fibers forms the spectrograph pseudo-slit. The fixed geometry of the collimator and camera configuration requires prisms in addition to the flat windows of the volume phase holographic gratings. There are 73 optical elements of large aperture and high precision manufactured in Mexico at the Instituto Nacional de Astrofísica, Óptica y Electrónica (INAOE) and the Centro de Investigaciones en Óptica (CIO). The principle of stitching interferometry is to divide the surface being tested into overlapping small sections, which allows an easier analysis (Kim & Wyant 1981). This capability is ideal for non-contact tests for unique and large optics as required by astronomical instruments. We show that the results obtained with our sub-aperture stitching algorithm were consistent with other methods that analyze the entire aperture. We used this method to analyze the 24 MEGARA prisms that could not be tested otherwise. The instrument has been successfully commissioned at GTC in all the spectral configurations. The fulfillment of the irregularity specifications was one of the necessary conditions to comply with the spectral requirements.

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.;

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).

CARMENES: First Results from the CAHA 3.5m Telescope

NASA Astrophysics Data System (ADS)

Quirrenbach, Andreas; Consortium, CARMENES

2015-12-01

CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs) is a next-generation instrument currently undergoing commissioning at the 3.5m telescope at the Calar Alto Observatory. It has been developed by a consortium of eleven Spanish and German institutions (see also Quirrenbach et al. 2010; 2012; 2014). CARMENES will conduct a 600-night exoplanet survey targeting ~300 M dwarfs. An important and unique feature of the CARMENES instrument is that it consists of two separate échelle spectrographs, which together cover the wavelength range from 0.55 to 1.7 μm at a spectral resolution of R = 82,000. The spectrographs are fed by fibers from the Cassegrain focus of the telescope.The main scientific objective of the CARMENES project is to carry out a survey of late-type main sequence stars with the goal of detecting low-mass planets in their habitable zones (HZs). In the focus of the project are very cool stars later than spectral type M4 and moderately active stars. We aim at being able to detect a 2M⊕ planet in the HZ of an M5 star. A long-term radial velocity precision of 1ms-1 per measurement will permit to attain such goals. For stars later than M4 (M < 0.25M⊙), such precision will yield detections of super-Earths of 5M⊕ and smaller inside the entire width of the HZ. The CARMENES survey will thus provide a comprehensive overview of planetary systems around nearby Northern M dwarfs. By reaching into the realm of Earth-like planets, it will provide a treasure trove for follow-up studies probing their habitability.Quirrenbach, A., Amado, P.J., Mandel, H., et al. (2010). CARMENES: Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs. In Ground-based and airborne instrumentation for astronomy III. Eds. McLean, I.S., Ramsay, S.K., & Takami, H., SPIE 773513Quirrenbach, A., Amado, P.J., Seifert, W., et al. (2012). CARMENES. I: Instrument and survey overview. In Ground-based and airborne instrumentation for astronomy IV. Eds. McLean, I.S., Ramsay, S.K., & Takami, H., SPIE 84460RQuirrenbach, A., Amado, P.J., Caballero, J.A., et al. (2014). CARMENES instrument overview. In Ground-based and airborne instrumentation for astronomy V. Eds. Ramsay, S.K., McLean, I.S., & Takami, H., SPIE 91471F

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.

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.

VizieR Online Data Catalog: HARPS-N radial velocities of KOI-70 (Buchhave+, 2016)

NASA Astrophysics Data System (ADS)

Buchhave, L. A.; Dressing, C. D.; Dumusque, X.; Rice, K.; Vanderburg, A.; Mortier, A.; Lopez-Morales, M.; Lopez, E.; Lundkvist, M. S.; Kjeldsen, H.; Affer, L.; Bonomo, A. S.; Charbonneau, D.; Collier, Cameron A.; Cosentino, R.; Figueira, P.; Fiorenzano, A. F. M.; Harutyunyan, A.; Haywood, R. D.; Johnson, J. A.; Latham, D. W.; Lovis, C.; Malavolta, L.; Mayor, M.; Micela, G.; Molinari, E.; Motalebi, F.; Nascimbeni, V.; Pepe, F.; Phillips, D. F.; Piotto, G.; Pollacco, D.; Queloz, D.; Sasselov, D.; Segransan, D.; Sozzetti, A.; Udry, S.; Watson, C.

2017-01-01

We obtained 125 observations of Kepler-20 (KOI-70, KIC 6850504, 2MASS J19104752+4220194) with the HARPS-N spectrograph on the 3.58m Telescopio Nazionale Galileo (TNG) located at Roque de Los Muchachos Observatory, La Palma, Spain. HARPS-N is an updated version of the original HARPS spectrograph on the 3.6m telescope at the European Southern Observatory on La Silla, Chile. HARPS-N is an ultra-stable fiber-fed high-resolution (R=115000) spectrograph with an optical wavelength coverage from 383 to 693nm. We obtained 61 and 64 observations of Kepler-20 in the 2014 and 2015 observing seasons, respectively (125 observations in total). We rejected 21 observations obtained under poor observing conditions where the internal error estimate exceeded 5m/s leaving a total of 104 observations. Kepler-20 has a mV=12.5 and required 30 minute exposure times to build up an adequate signal-to-noise ratio (S/N). The average S/N per pixel of the observations at 550nm is 30, yielding an average internal uncertainty estimate of 3.66m/s. The radial velocities and their 1σ errors are shows in Table1. (1 data file).

VizieR Online Data Catalog: Radial velocities for the HD 3167 system (Christiansen+, 2017)

NASA Astrophysics Data System (ADS)

Christiansen, J. L.; Vanderburg, A.; Burt, J.; Fulton, B. J.; Batygin, K.; Benneke, B.; Brewer, J. M.; Charbonneau, D.; Ciardi, D. R.; Cameron, A. C.; Coughlin, J. L.; Crossfield, I. J. M.; Dressing, C.; Greene, T. P.; Howard, A. W.; Latham, D. W.; Molinari, E.; Mortier, A.; Mullally, F.; Pepe, F.; Rice, K.; Sinukoff, E.; Sozzetti, A.; Thompson, S. E.; Udry, S.; Vogt, S. S.; Barman, T. S.; Batalha, N. E.; Bouchy, F.; Buchhave, L. A.; Butler, R. P.; Cosentino, R.; Dupuy, T. J.; Ehrenreich, D.; Fiorenzano, A.; Hansen, B. M. S.; Henning, T.; Hirsch, L.; Holden, B. P.; Isaacson, H. T.; Johnson, J. A.; Knutson, H. A.; Kosiarek, M.; Lopez-Morales, M.; Lovis, C.; Malavolta, L.; Mayor, M.; Micela, G.; Motalebi, F.; Petigura, E.; Phillips, D. F.; Piotto, G.; Rogers, L. A.; Sasselov, D.; Schlieder, J. E.; Segransan, D.; Watson, C. A.; Weiss, L. M.

2018-06-01

The final data set includes observations obtained with Keck/HIRES, Automated Planet Finder (APF)/Levy, and HARPS-N. Our observational setup for both Keck/HIRES and the APF/Levy was essentially identical to those described in Fulton et al. (2016, J/ApJ/830/46) and Burt et al. (2014ApJ...789..114B). We collected a total of 60 RV measurements using Keck/HIRES (Vogt et al. 1994SPIE.2198..362V), and 116 measurements using the Levy Spectrograph on the APF (Radovan et al. 2014SPIE.9145E..2BR; Vogt et al. 2014PASP..126..359V) at Lick Observatory between 2016 July 7 and 2016 December 2. We also observed HD 3167 with the HARPS-N spectrograph (Cosentino et al. 2012SPIE.8446E..1VC) located at the 3.58 m Telescopio Nazionale Galileo on the island of La Palma, Spain. HARPS-N is a stabilized spectrograph designed for precise RV measurements. We observed HD 3167 76 times between 2016 July 7 (independently beginning the same night as the HIRES/APF campaign) and 2016 December 7, obtaining high-resolution optical spectra with a spectral resolving power of R=115000. (1 data file).

GIARPS@TNG: GIANO-B and HARPS-N together for a wider wavelength range spectroscopy

NASA Astrophysics Data System (ADS)

Claudi, R.; Benatti, S.; Carleo, I.; Ghedina, A.; Guerra, J.; Micela, G.; Molinari, E.; Oliva, E.; Rainer, M.; Tozzi, A.; Baffa, C.; Baruffolo, A.; Buchschacher, N.; Cecconi, M.; Cosentino, R.; Fantinel, D.; Fini, L.; Ghinassi, F.; Giani, E.; Gonzalez, E.; Gonzalez, M.; Gratton, R.; Harutyunyan, A.; Hernandez, N.; Lodi, M.; Malavolta, L.; Maldonado, J.; Origlia, L.; Sanna, N.; Sanjuan, J.; Scuderi, S.; Seemann, U.; Sozzetti, A.; Perez Ventura, H.; Hernandez Diaz, M.; Galli, A.; Gonzalez, C.; Riverol, L.; Riverol, C.

2017-08-01

Since 2012, thanks to the installation of the high-resolution echelle spectrograph in the optical range HARPS-N, the Italian telescope TNG (La Palma) became one of the key facilities for the study of the extrasolar planets. In 2014 TNG also offered GIANO to the scientific community, providing a near-infrared (NIR) cross-dispersed echelle spectroscopy covering 0.97-2.45μm at a resolution of 50000. GIANO, although designed for direct light-feed from the telescope at the Nasmyth-B focus, was provisionally mounted on the rotating building and connected via fibers to only available interface at the Nasmyth-A focal plane. The synergy between these two instruments is particularly appealing for a wide range of science cases, especially for the search of exoplanets around young and active stars and the characterisation of their atmosphere. Through the funding scheme "WOW" (a Way to Others Worlds), the Italian National Institute for Astrophysics (INAF) proposed to position GIANO at the focal station for which it was originally designed and the simultaneous use of these spectrographs with the aim to achieve high-resolution spectroscopy in a wide wavelength range (0.383-2.45μm) obtained in a single exposure, giving rise to the project called GIARPS (GIANO-B & HARPS-N). Because of its characteristics, GIARPS can be considered the first and unique worldwide instrument providing not only high resolution in a large wavelength band, but also a high-precision radial velocity measurement both in the visible and in the NIR arm, since in the next future GIANO-B will be equipped with gas absorption cells.

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.

The JWST/NIRSpec instrument: update on status and performances

NASA Astrophysics Data System (ADS)

Birkmann, Stephan M.; Ferruit, Pierre; Rawle, Tim; Sirianni, Marco; Alves de Oliveira, Catarina; Böker, Torsten; Giardino, Giovanna; Lützgendorf, Nora; Marston, Anthony; Stuhlinger, Martin; te Plate, Maurice B. J.; Jensen, Peter; Rumler, Peter; Dorner, Bernhard; Karl, Hermann; Mosner, Peter; Wright, Raymond H.; Rapp, Robert

2016-07-01

The Near-Infrared Spectrograph (NIRSpec) is one of the four instruments on the James Webb Space Telescope (JWST) which is scheduled for launch in 2018. NIRSpec is developed by the European Space Agency (ESA) with Airbus Defense and Space Germany as prime contractor. The instrument offers seven dispersers covering the wavelength range from 0.6 to 5.3 micron with resolutions from R ˜ 100 to R ˜ 2700. NIRSpec will be capable of obtaining spectra for more than 100 objects simultaneously using an array of micro-shutters. It also features an integral field unit with 3" x 3" field of view and a range of slits for high contrast spectroscopy of individual objects and time series observations of e.g. transiting exoplanets. NIRSpec is in its final flight configuration and underwent cryogenic performance testing at the Goddard Space Flight Center in Winter 2015/16 as part of the Integrated Science Instrument Module (ISIM). We present the current status of the instrument and also provide an update on NIRSpec performances based on results from the ISIM level test campaign.

Spectral Analysis Flare ribbons by NST and IRIS

NASA Astrophysics Data System (ADS)

Huang, Nengyi; Xu, Yan; Wang, Haimin; Jing, Ju

2017-08-01

As one of the most powerful phenomena of solar activities, flares have long been observed and studied extensively. Taking advantages of observing capabilities of modern solar telescopes and focal-plane instruments such as the Interface Region Imaging Spectrograph (IRIS) and the 1.6 m New Solar Telescope (NST) at Big Bear Solar observatory (BBSO), we are able to obtain high resolution imaging spectroscopic data in UV, visible and near-infrared (NIR) wavelengths. Here we present the spectral analysis of an M6.5 flare (SOL2015-06-22T18:23) which was well covered by the joint observation of IRIS and NST. In the visible wavelengths H-alpha and TiO, we can separate the flare ribbon into a very narrow leading front and faint trailing component, of which the former is characterized by the intense emission and significant Doppler signals. In the IRIS UV spectra, the ribbon front shows distinct properties, such as the line broadening, Doppler shifts and central reversal pattern, which are consistent with the visible observations. These characteristics suggest that the ribbon front to be the p

SOAP. A tool for the fast computation of photometry and radial velocity induced by stellar spots

NASA Astrophysics Data System (ADS)

Boisse, I.; Bonfils, X.; Santos, N. C.

2012-09-01

We define and put at the disposal of the community SOAP, Spot Oscillation And Planet, a software tool that simulates the effect of stellar spots and plages on radial velocimetry and photometry. This paper describes the tool release and provides instructions for its use. We present detailed tests with previous computations and real data to assess the code's performance and to validate its suitability. We characterize the variations of the radial velocity, line bisector, and photometric amplitude as a function of the main variables: projected stellar rotational velocity, filling factor of the spot, resolution of the spectrograph, linear limb-darkening coefficient, latitude of the spot, and inclination of the star. Finally, we model the spot distributions on the active stars HD 166435, TW Hya and HD 189733, which reproduce the observations. We show that the software is remarkably fast, allowing several evolutions in its capabilities that could be performed to study the next challenges in the exoplanetary field connected with the stellar variability. The tool is available at http://www.astro.up.pt/soap

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.

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.

Spectroscopic classification of AT 2017ixr as a nova in M31

NASA Astrophysics Data System (ADS)

Williams, S. C.; Darnley, M. J.; Carey, G.

2018-01-01

We obtained spectra of the transient AT 2017ixr (see TNS) with the SPRAT spectrograph (resolution R 350; Piascik et al. 2014) on the 2-m Liverpool Telescope (LT; Steele et al. 2004) on 2017 Dec 27.90 and 2018 Jan 12.83 UT. The first spectrum (2017 Dec 27) shows narrow H & alpha; emission on a blue continuum.

Spectroscopic classification of TCP J00333837+4836022 as a nova in NGC 147

NASA Astrophysics Data System (ADS)

Williams, S. C.; Darnley, M. J.

2017-12-01

We obtained a spectrum of the transient TCP J00333837+4836022 (see CBAT TOCP) with the SPRAT spectrograph (resolution R 350; Piascik et al. 2014) on the 2-m Liverpool Telescope (Steele et al. 2004) on 2017 Dec 24.82 UT. The only emission clearly present is H & alpha;, which displays a P-Cygni profile.

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.

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.

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.

High-Resolution Spectroscopy at the Wyoming Infrared Observatory: Setting TESS Science on FHiRE

NASA Astrophysics Data System (ADS)

Jang-Condell, Hannah; Pierce, Michael J.; Pilachowski, C. A.; Kobulnicky, Henry; McLane, Jacob N.

2018-01-01

The Fiber High Resolution Echelle (FHiRE) spectrograph is a new instrument designed for the 2.3-m Wyoming InfraRed Observatory (WIRO). With the construction of a vacuum chamber for FHiRE to stabilize the spectrograph and a temperature-stabilized Thorium-Argon lamp for precise velocity calibration, we will be able to achieve 1 m/s RV precision, making it an ideal instrument for finding exoplanets. Details of the design of FHiRE are presented in a companion poster (Pierce et al.). The construction of this instrument is well-timed with the planned 2018 launch of NASA's Transiting Exoplanet Survey Satellite (TESS) mission. TESS will require a great deal of follow-up spectroscopy to characterize potential exoplanet host stars as well as radial velocity measurements to confirm new exoplanets. WIRO is ideally suited to acquire the long-term, high-cadence observations that will be required to make progress in this frontier area of astrophysics. We will coordinate our efforts with the TESS Follow-up Observing Program (TFOP), specifically as part of the Recon Spectroscopy and Precise Radial Velocity Work sub-groups.This work is supported by a grant from NASA EPSCOR.

Cosmological surveys with multi-object spectrographs

NASA Astrophysics Data System (ADS)

Colless, Matthew

2016-08-01

Multi-object spectroscopy has been a key technique contributing to the current era of `precision cosmology.' From the first exploratory surveys of the large-scale structure and evolution of the universe to the current generation of superbly detailed maps spanning a wide range of redshifts, multi-object spectroscopy has been a fundamentally important tool for mapping the rich structure of the cosmic web and extracting cosmological information of increasing variety and precision. This will continue to be true for the foreseeable future, as we seek to map the evolving geometry and structure of the universe over the full extent of cosmic history in order to obtain the most precise and comprehensive measurements of cosmological parameters. Here I briefly summarize the contributions that multi-object spectroscopy has made to cosmology so far, then review the major surveys and instruments currently in play and their prospects for pushing back the cosmological frontier. Finally, I examine some of the next generation of instruments and surveys to explore how the field will develop in coming years, with a particular focus on specialised multi-object spectrographs for cosmology and the capabilities of multi-object spectrographs on the new generation of extremely large telescopes.

VIRUS: first deployment of the massively replicated fiber integral field spectrograph for the upgraded Hobby-Eberly Telescope

NASA Astrophysics Data System (ADS)

Hill, Gary J.; Tuttle, Sarah E.; Vattiat, Brian L.; Lee, Hanshin; Drory, Niv; Kelz, Andreas; Ramsey, Jason; Peterson, Trent W.; DePoy, D. L.; Marshall, J. L.; Gebhardt, Karl; Chonis, Taylor; Dalton, Gavin; Farrow, Daniel; Good, John M.; Haynes, Dionne M.; Indahl, Briana L.; Jahn, Thomas; Kriel, Hermanus; Montesano, Francesco; Nicklas, Harald; Noyola, Eva; Prochaska, Travis; Allen, Richard D.; Bender, Ralf; Blanc, Guillermo; Fabricius, Maximilian H.; Finkelstein, Steve; Landriau, Martin; MacQueen, Phillip J.; Roth, M. M.; Savage, R. D.; Snigula, Jan M.; Anwad, Heiko

2016-08-01

The Visible Integral-field Replicable Unit Spectrograph (VIRUS) consists of 156 identical spectrographs (arrayed as 78 pairs) fed by 35,000 fibers, each 1.5 arcsec diameter, at the focus of the upgraded 10 m Hobby-Eberly Telescope (HET). VIRUS has a fixed bandpass of 350-550 nm and resolving power R 700. VIRUS is the first example of industrial-scale replication applied to optical astronomy and is capable of surveying large areas of sky, spectrally. The VIRUS concept offers significant savings of engineering effort, cost, and schedule when compared to traditional instruments. The main motivator for VIRUS is to map the evolution of dark energy for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX‡), using 0.8M Lyman-alpha emitting galaxies as tracers. The VIRUS array is undergoing staged deployment during 2016 and 2017. It will provide a powerful new facility instrument for the HET, well suited to the survey niche of the telescope, and will open up large spectroscopic surveys of the emission line universe for the first time. We will review the production, lessons learned in reaching volume production, characterization, and first deployment of this massive instrument.

Dramatic robustness of a multiple delay dispersed interferometer to spectrograph errors: how mixing delays reduces or cancels wavelength drift

NASA Astrophysics Data System (ADS)

Erskine, David J.; Linder, E.; Wishnow, E.; Edelstein, J.; Sirk, M.; Muirhead, P.; Lloyd, J.; Kim, A.

2016-08-01

We describe demonstrations of remarkable robustness to instrumental noises by using a multiple delay externally dispersed interferometer (EDI) on stellar observations at the Hale telescope. Previous observatory EDI demonstrations used a single delay. The EDI (also called "TEDI") boosted the 2,700 resolution of the native TripleSpec NIR spectrograph (950-2450 nm) by as much as 10x to 27,000, using 7 overlapping delays up to 3 cm. We observed superb rejection of fixed pattern noises due to bad pixels, since the fringing signal responds only to changes in multiple exposures synchronous to the applied delay dithering. Remarkably, we observed a 20x reduction of reaction in the output spectrum to PSF shifts of the native spectrograph along the dispersion direction, using our standard processing. This allowed high resolution observations under conditions of severe and irregular PSF drift otherwise not possible without the interferometer. Furthermore, we recently discovered an improved method of weighting and mixing data between pairs of delays that can theoretically further reduce the net reaction to PSF drift to zero. We demonstrate a 350x reduction in reaction to a native PSF shift using a simple simulation. This technique could similarly reduce radial velocity noise for future EDI's that use two delays overlapped in delay space (or a single delay overlapping the native peak). Finally, we show an extremely high dynamic range EDI measurement of our ThAr lamp compared to a literature ThAr spectrum, observing weak features ( 0.001x height of nearest strong line) that occur between the major lines. Because of individuality of each reference lamp, accurate knowledge of its spectrum between the (unfortunately) sparse major lines is important for precision radial velocimetry.

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).

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.

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).

Chemical abundances of fast-rotating massive stars. I. Description of the methods and individual results

NASA Astrophysics Data System (ADS)

Cazorla, Constantin; Morel, Thierry; Nazé, Yaël; Rauw, Gregor; Semaan, Thierry; Daflon, Simone; Oey, M. S.

2017-07-01

Aims: Recent observations have challenged our understanding of rotational mixing in massive stars by revealing a population of fast-rotating objects with apparently normal surface nitrogen abundances. However, several questions have arisen because of a number of issues, which have rendered a reinvestigation necessary; these issues include the presence of numerous upper limits for the nitrogen abundance, unknown multiplicity status, and a mix of stars with different physical properties, such as their mass and evolutionary state, which are known to control the amount of rotational mixing. Methods: We have carefully selected a large sample of bright, fast-rotating early-type stars of our Galaxy (40 objects with spectral types between B0.5 and O4). Their high-quality, high-resolution optical spectra were then analysed with the stellar atmosphere modelling codes DETAIL/SURFACE or CMFGEN, depending on the temperature of the target. Several internal and external checks were performed to validate our methods; notably, we compared our results with literature data for some well-known objects, studied the effect of gravity darkening, or confronted the results provided by the two codes for stars amenable to both analyses. Furthermore, we studied the radial velocities of the stars to assess their binarity. Results: This first part of our study presents our methods and provides the derived stellar parameters, He, CNO abundances, and the multiplicity status of every star of the sample. It is the first time that He and CNO abundances of such a large number of Galactic massive fast rotators are determined in a homogeneous way. Based on observations obtained with the Heidelberg Extended Range Optical Spectrograph (HEROS) at the Telescopio Internacional de Guanajuato (TIGRE) with the SOPHIE échelle spectrograph at the Haute-Provence Observatory (OHP; Institut Pytheas; CNRS, France), and with the Magellan Inamori Kyocera Echelle (MIKE) spectrograph at the Magellan II Clay telescope. Based also on archival data from the Galactic O-Star Spectroscopic Survey (GOSSS), the Anglo-Australian Telescope (AAT) equipped with the University College London Echelle Spectrograph (UCLES), the ESO/La Silla Observatory with the Fiber-fed Extended Range Optical Spectrograph (FEROS; programmes 70.D-0110, 075.D-0061, 076.C-0431, 081.D-2008, 083.D-0589, 086.D-0997, 087.D-0946, 089.D-0189, 089.D-0975, 179.C-0197, and the High Accuracy Radial velocity Planet Searcher (HARPS; programme 60.A-9036), the Pic du Midi Observatory equipped with the NARVAL spectropolarimeter, the San Pedro Mártir (SPM) observatory with the Echelle SPectrograph for Rocky Exoplanet and Stable Spectroscopic Observations (ESPRESSO), the OHP with the AURELIE and ELODIE échelle spectrographs, the Nordic Optical Telescope (NOT) with the FIbre-fed Echelle Spectrograph (FIES), the Canada-France-Hawaii Telescope (CFHT), with the Echelle SpectroPolarimetric Device for the Observation of Stars (ESPaDOnS) spectrograph, the Leonhard Euler Telescope with the CORALIE spectrograph.Table F.2 is also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/603/A56

Spectroscopic binary orbits from ultraviolet radial velocities. X - CW Cephei (HD 218066)

NASA Technical Reports Server (NTRS)

Stickland, D. J.; Koch, R. H.; Pfeiffer, R. J.

1992-01-01

Observations of CW Cephei were carried out repeatedly in the course of three days in December 1991, using the high-resolution, short-wavelength spectrograph of IUE, with an additional spectrum taken on February 6, 1992. The paper presents a log of these observations, which represent the only high-resolution observations of this star in the archive. The observations have an advantage of Popper's (1974) optical observations that they do not stretch out over a significant part of the apsidal cycle and can thus be treated with the value of omega taken as fixed.

VizieR Online Data Catalog: Equivalent widths and atomic data for GCs (Lamb+, 2015)

NASA Astrophysics Data System (ADS)

Lamb, M. P.; Venn, K. A.; Shetrone, M. D.; Sakari, C. M.; Pritzl, B. J.

2017-11-01

Optical spectra were gathered with the High Resolution Spectrograph (HRS; Tull 1998, Proc. SPIE, 3355, 387) on the HET. The HRS was configured at resolution R=30000 with 2x2 pixel binning using the 2 arcsec fibre. The HRS splits the incoming beam on to two CCD chips, from which the spectral regions 6000-7000 Å (red chip) and 4800-5900 Å (blue chip) were extracted for this work. Two standard stars were also observed, RGB stars with previously published spectral analyses in each of the GCs M3 and M13. (2 data files).

VizieR Online Data Catalog: Praesepe members with K2 light curve data (Rebull+, 2017)

NASA Astrophysics Data System (ADS)

Rebull, L. M.; Stauffer, J. R.; Hillenbrand, L. A.; Cody, A. M.; Bouvier, J.; Soderblom, D. R.; Pinsonneault, M.; Hebb, L.

2017-11-01

Praesepe members and candidate members were observed in K2 Campaign 5, which lasted for 75 days between 2015 April and October. We obtained high resolution spectra for several of the anomalously slowly rotating stars and all of the objects with odd light curves (Section 4.3) using the Keck HIRES spectrograph. The observations were taken on one of 2016 October 14, December 22, December 26, or 2017 January 13, UT, and cover the wavelength range roughly 4800-9200Å at a spectral resolution of R~45000. (10 data files).

StarNet: An application of deep learning in the analysis of stellar spectra

NASA Astrophysics Data System (ADS)

Kielty, Collin; Bialek, Spencer; Fabbro, Sebastien; Venn, Kim; O'Briain, Teaghan; Jahandar, Farbod; Monty, Stephanie

2018-06-01

In an era when spectroscopic surveys are capable of collecting spectra for hundreds of thousands of stars, fast and efficient analysis methods are required to maximize scientific impact. These surveys provide a homogeneous database of stellar spectra that are ideal for machine learning applications. In this poster, we present StarNet: a convolutional neural network model applied to the analysis of both SDSS-III APOGEE DR13 and synthetic stellar spectra. When trained on synthetic spectra alone, the calculated stellar parameters (temperature, surface gravity, and metallicity) are of excellent precision and accuracy for both APOGEE data and synthetic data, over a wide range of signal-to-noise ratios. While StarNet was developed using the APOGEE observed spectra and corresponding ASSeT synthetic grid, we suggest that this technique is applicable to other spectral resolutions, spectral surveys, and wavelength regimes. As a demonstration of this, we present a StarNet model trained on lower resolution, R=6000, IR synthetic spectra, describing the spectra delivered by Gemini/NIFS and the forthcoming Gemini/GIRMOS instrument (PI Sivanandam, UToronto). Preliminary results suggest that the stellar parameters determined from this low resolution StarNet model are comparable in precision to the high-resolution APOGEE results. The success of StarNet at lower resolution can be attributed to (1) a large training set of synthetic spectra (N ~200,000) with a priori stellar labels, and (2) the use of the entire spectrum in the solution rather than a few weighted windows, which are common methods in other spectral analysis tools (e.g. FERRE or The Cannon). Remaining challenges in our StarNet applications include rectification, continuum normalization, and wavelength coverage. Solutions to these problems could be used to guide decisions made in the development of future spectrographs, spectroscopic surveys, and data reduction pipelines, such as for the future MSE.

MOEMs devices designed and tested for future astronomical instrumentation in space

NASA Astrophysics Data System (ADS)

Zamkotsian, Frédéric; Lanzoni, Patrick; Waldis, Severin; Noell, Wilfried; Conedera, Veronique; Fabre, Norbert; Viard, Thierry; Buisset, Christophe

2017-11-01

Next generation of astronomical instrumentation for space telescopes requires Micro-Opto-Electro- Mechanical Systems (MOEMS) with remote control capability and cryogenic operation. MOEMS devices have the capability to tailor the incoming light in terms of intensity and object selection with programmable slit masks, in terms of phase and wavefront control with micro-deformable mirrors, and finally in terms of spectrum with programmable diffraction gratings. Applications are multi-object spectroscopy (MOS), wavefront correction and programmable spectrographs. We are engaged since several years in the design, realization and characterization of MOEMS devices suited for astronomical instrumentation.

CAFE: Calar Alto Fiber-fed Échelle spectrograph

NASA Astrophysics Data System (ADS)

Aceituno, J.; Sánchez, S. F.; Grupp, F.; Lillo, J.; Hernán-Obispo, M.; Benitez, D.; Montoya, L. M.; Thiele, U.; Pedraz, S.; Barrado, D.; Dreizler, S.; Bean, J.

2013-04-01

We present here CAFE, the Calar Alto Fiber-fed Échelle spectrograph, a new instrument built at the Centro Astronomico Hispano Alemán (CAHA). CAFE is a single-fiber, high-resolution (R ~ 70 000) spectrograph, covering the wavelength range between 3650-9800 Å. It was built on the basis of the common design for Échelle spectrographs. Its main aim is to measure radial velocities of stellar objects up to V ~ 13-14 mag with a precision as good as a few tens of m s-1. To achieve this goal the design was simplified at maximum, removing all possible movable components, the central wavelength is fixed, as is the wavelength coverage; there is no filter wheel, etc. Particular care was taken with the thermal and mechanical stability. The instrument is fully operational and publically accessible at the 2.2 m telescope of the Calar Alto Observatory. In this article we describe (i) the design, summarizing its manufacturing phase; (ii) characterize the main properties of the instrument; (iii) describe the reduction pipeline; and (iv) show the results from the first light and commissioning runs. The preliminar results indicate that the instrument fulfills the specifications and can achieve the planned goals. In particular, the results show that the instrument is more efficient than anticipated, reaching a signal-to-noise of ~20 for a stellar object as faint as V ~ 14.5 mag in ~2700 s integration time. The instrument is a wonderful machine for exoplanetary research (by studying large samples of possible systems cotaining massive planets), galactic dynamics (highly precise radial velocities in moving groups or stellar associations), or astrochemistry.

A high-resolution atlas of composite Sloan Digital Sky Survey galaxy spectra

NASA Astrophysics Data System (ADS)

Dobos, László; Csabai, István.; Yip, Ching-Wa; Budavári, Tamás.; Wild, Vivienne; Szalay, Alexander S.

2012-02-01

In this work we present an atlas of composite spectra of galaxies based on the data of the Sloan Digital Sky Survey Data Release 7 (SDSS DR7). Galaxies are classified by colour, nuclear activity and star formation activity to calculate average spectra of high signal-to-noise ratio (S/N) and resolution (? at Δλ= 1 Å), using an algorithm that is robust against outliers. Besides composite spectra, we also compute the first five principal components of the distributions in each galaxy class to characterize the nature of variations of individual spectra around the averages. The continua of the composite spectra are fitted with BC03 stellar population synthesis models to extend the wavelength coverage beyond the coverage of the SDSS spectrographs. Common derived parameters of the composites are also calculated: integrated colours in the most popular filter systems, line-strength measurements and continuum absorption indices (including Lick indices). These derived parameters are compared with the distributions of parameters of individual galaxies, and it is shown on many examples that the composites of the atlas cover much of the parameter space spanned by SDSS galaxies. By co-adding thousands of spectra, a total integration time of several months can be reached, which results in extremely low noise composites. The variations in redshift not only allow for extending the spectral coverage bluewards to the original wavelength limit of the SDSS spectrographs, but also make higher spectral resolution achievable. The composite spectrum atlas is available online at .

IGRINS on the DCT

NASA Astrophysics Data System (ADS)

Prato, Lisa A.

2017-01-01

Through an agreement with the University of Texas at Austin and the Korea Astronomy and Space Science Institute, the Immersion Grating Infrared Spectrograph (IGRINS) saw first light on the Lowell Observatory 4.3 m Discovery Channel Telescope (DCT) telescope on September 8, 2016. IGRINS, originally commissioned at the McDonald Observatory 2.7 m telescope, provides a spectral resolution of 45,000 and a simultaneous spectral grasp of 1.45 to 2.45 microns, recording all of the H and K bands with no gaps in wavelength coverage on two H2RG detectors in a single exposure. The instrument design minimizes optical surfaces, optimizing throughput, and has no moving parts, key for stability. IGRINS on the DCT attains a signal to noise of 100 per resolution element in one hour of integration time on a K=12 magnitude source, currently making it the most sensitive high-resolution spectrograph in the world at H and K. Science programs in the fourth quarter, 2016, include such diverse topics as abundance measurements in M dwarfs and population II stars, studies of ices and atmospheres in outer solar system bodies, measurement of fundamental properties of pre-main sequence stars, calibrating young star evolution, defining the substellar boundary at the youngest ages, outflow characteristics in Wolf-Rayet stars, finding the first generation of exoplanets, gas dynamics in planetary nebulae, and structure of the ISM in molecular clouds. In this talk I will report on initial results from selected programs.

VizieR Online Data Catalog: Spectroscopic analysis of 348 red giants (Zielinski+, 2012)

NASA Astrophysics Data System (ADS)

Zielinski, P.; Niedzielski, A.; Wolszczan, A.; Adamow, M.; Nowak, G.

2012-10-01

The atmospheric parameters were derived using a strictly spectroscopic method based on the LTE analysis of equivalent widths of FeI and FeII lines. With existing photometric data and the Hipparcos parallaxes, we estimated stellar masses and ages via evolutionary tracks fitting. The stellar radii were calculated from either estimated masses and the spectroscopic logg or from the spectroscopic Teff and estimated luminosities. The absolute radial velocities were obtained by cross-correlating spectra with a numerical template. Our high-quality, high-resolution optical spectra have been collected since 2004 with the Hobby-Eberly Telescope (HET), located in the McDonald Observatory. The telescope was equipped with the High Resolution Spectrograph (HRS; R~60000 resolution). (2 data files).

Near-infrared Spectroscopic Observations of Comet C/2013 R1 (Lovejoy) by WINERED: CN Red-system Band Emission

NASA Astrophysics Data System (ADS)

Shinnaka, Yoshiharu; Kawakita, Hideyo; Kondo, Sohei; Ikeda, Yuji; Kobayashi, Naoto; Hamano, Satoshi; Sameshima, Hiroaki; Fukue, Kei; Matsunaga, Noriyuki; Yasui, Chikako; Izumi, Natsuko; Mizumoto, Misaki; Otsubo, Shogo; Takenaka, Keiichi; Watase, Ayaka; Kawanishi, Takafumi; Nakanishi, Kenshi; Nakaoka, Tetsuya

2017-08-01

Although high-resolution spectra of the CN red-system band are considered useful in cometary sciences, e.g., in the study of isotopic ratios of carbon and nitrogen in cometary volatiles, there have been few reports to date due to the lack of high-resolution (R ≡ λ/Δλ > 20,000) spectrographs in the near-infrared region around ˜1 μm. Here, we present the high-resolution emission spectrum of the CN red-system band in comet C/2013 R1 (Lovejoy), acquired by the near-infrared high-resolution spectrograph WINERED mounted on the 1.3 m Araki telescope at the Koyama Astronomical Observatory, Kyoto, Japan. We applied our fluorescence excitation models for CN, based on modern spectroscopic studies, to the observed spectrum of comet C/2013 R1 (Lovejoy) to search for CN isotopologues (13C14N and 12C15N). We used a CN fluorescence excitation model involving both a “pure” fluorescence excitation model for the outer coma and a “fully collisional” fluorescence excitation model for the inner coma region. Our emission model could reproduce the observed 12C14N red-system band of comet C/2013 R1 (Lovejoy). The derived mixing ratio between the two excitation models was 0.94(+0.02/-0.03):0.06(+0.03/-0.02), corresponding to the radius of the collision-dominant region of ˜800-1600 km from the nucleus. No isotopologues were detected. The observed spectrum is consistent, within error, with previous estimates in comets of 12C/13C (˜90) and 14N/15N (˜150).

On the relation between spectral characteristics of the microwave emission from solar active regions and physical conditions of the solar atmosphere.

NASA Astrophysics Data System (ADS)

Kaverin, N. S.; Kobrin, M. M.; Korshunov, A. I.; Shushunov, V. V.; Aurass, H.; Fürstenberg, F.; Hildebrandt, J.; Krüger, A.; Seehafer, N.

Spectrographic observations of the microwave emission from selected active regions were analysed and compared with S-component emission models. The observations were obtained by spectrographs of the NIRFI working in the ranges 12 - 8 and 7 - 5 GHz covering the high-frequency part of the S-component spectrum. The measurements were carried out at the RT-22 radio telescope of the FIAN Radio Astronomy Station at Pushtshino with an angular resolution of about 9 arc minutes. The conclusions obtained mainly relate to the reversal of the slope of the flux spectrum in the short cm-region by the change of the emission mechanism, to an excess of the observed flux spectrum at long cm-waves and to the interpretation of the proton-flare criterion of Tanaka and Kakinuma on the basis of model calculations.

Rocket spectrogram of a solar flare in the 10-100 A region

NASA Technical Reports Server (NTRS)

Acton, L. W.; Bruner, M. E.; Brown, W. A.; Fawcett, B. C.; Schweizer, W.; Speer, R. J.

1985-01-01

The soft (10-100 A) X-ray spectrum of an M-class solar flare was observed with a high-resolution (0.02 A) rocket-borne spectrograph on 1982 July 13. The spectrum samples an area of 600/sq arcsec on the sun, centered on or near the brightest X-ray feature of the flare. Several hundred emission lines characteristic of temperatures from about 0.5 to 7 x 10 to the 6th K have been photographically recorded. All but three of the stronger lines have been identified. It is argued that previous identification of the line at 17.62 A as iron Ly-alpha is incorrect. Spectral lines from nickel, iron, chromium, calcium, sulphur, silicon, aluminium, magnesium, neon, oxygen, nitrogen, and carbon are tabulated and discussed with extensive reference to earlier work. Absolute line intensities are given and the calibration of the telescope-spectrograph is 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.

VizieR Online Data Catalog: Elemental abundances of solar sibling candidates (Ramirez+, 2014)

NASA Astrophysics Data System (ADS)

Ramirez, I.; Bajkova, A. T.; Bobylev, V. V.; Roederer, I. U.; Lambert, D. L.; Endl, M.; Cochran, W. D.; MacQueen, P. J.; Wittenmyer, R. A.

2017-06-01

We used the Tull coude spectrograph on the 2.7 m Harlan J. Smith Telescope at McDonald Observatory (Tull et al. 1995PASP..107..251T) to observe most of our targets (23). All but three of them were observed in 2012 December; the others were observed in 2013 March. The rest of our targets (seven) have too-low declinations to be observed from McDonald Observatory. Instead, they were observed using the Magellan Inamori Kyocera Echelle (MIKE) spectrograph on the 6.5 m Telescope at Las Campanas Observatory (Bernstein et al. 2003SPIE.4841.1694B) in 2013 April. Slit sizes were chosen so that the spectral resolution of the data is about 60000 in the visible part of the spectrum. We targeted a S/N per pixel of at least 200 at 6000 Å. Only one of our targets (HD 46100) has a significantly lower S/N spectrum. (2 data files).

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.

Spectrographs and Large Telescopes: A Study of Instrumentation

NASA Astrophysics Data System (ADS)

Fica, Haley Diane; Crane, Jeffrey D.; Uomoto, Alan K.; Hare, Tyson

2017-01-01

It is a truth universally acknowledged, that a telescope in possession of a large aperture, must be in want of a high resolution spectrograph. Subsystems of these instruments require testing and upgrading to ensure that they can continue to be scientifically productive and usher in a new era of astronomical research. The Planet Finder Spectrograph (PFS) and Magellan Inamori Kyocera Echelle (MIKE), both on the Magellan II Clay telescope at Las Campanas Observatory, and the Giant Magellan Telescope (GMT) Consortium Large Earth Finder (G-CLEF) are examples of such instruments. Bluer flat field lamps were designed for PFS and MIKE to replace lamps no longer available in order to ensure continued, efficient functionality. These newly designed lamps will result in better flat fielding and calibration of data, and thus result in increased reduction of instrument noise. When it is built and installed in 2022, G-CLEF will be be fed by a tertiary mirror on the GMT. Stepper motors attached to the back of this mirror will be used to correct misalignments in the optical relay system. These motors were characterized to ensure that they function as expected to an accuracy of a few microns. These projects incorporate several key aspects of astronomical instrumentation: designing, building, and testing.

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.

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.

VizieR Online Data Catalog: Kepler-10 RV measurements by HARPS-N (Dumusque+, 2014)

NASA Astrophysics Data System (ADS)

Dumusque, X.; Bonomo, A. S.; Haywood, R. D.; Malavolta, L.; Segransan, D.; Buchhave, L. A.; Collier, Cameron A.; Latham, D. W.; Molinari, E.; Pepe, F.; Udry, S.; Charbonneau, D.; Cosentino, R.; Dressing, C. D.; Figueira, P.; Fiorenzano, A. F. M.; Gettel, S.; Harutyunyan, A.; Horne, K.; Lopez-Morales, M.; Lovis, C.; Mayor, M.; Micela, G.; Motalebi, F.; Nascimbeni, V.; Phillips, D. F.; Piotto, G.; Pollacco, D.; Queloz, D.; Rice, K.; Sasselov, D.; Sozzetti, A.; Szentgyorgyi, A.; Watson, C.

2017-03-01

We monitored the RV variation of Kepler-10 with the HARPS-N spectrograph installed on the 3.57-m Telescopio Nazionale Galileo at the Spanish Observatorio del Roque de los Muchachos, La Palma Island, Spain (Cosentino et al. 2012SPIE.8446E..1VC). This instrument is an updated version of the original HARPS planet hunter installed on the 3.6-m telescope at the European Southern Observatory on La Silla, Chile (Mayor et al. 2003Msngr.114...20M). Just like its older brother, the HARPS-N instrument is an ultra-stable fiber-fed high-resolution (R = 115,000) optical echelle spectrograph optimized for the measurement of very precise RVs. The use of a more modern monolithic 4kx4k CCD enclosed in a more temperature stable cryostat, and the use of octagonal fibers for a better scrambling of the incoming light fed into the spectrograph should improve the precision of the instrument compared to HARPS. Scientific operations began at HARPS-N in 2012 August. Over the first two observing seasons, we obtained 157 RV measurements of Kepler-10. Four observations that were obtained during bad weather conditions had very low signal to noise (S/N, <10) and were rejected. (1 data file).

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.

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.

Prospects for measuring supermassive black hole masses with future extremely large telescopes

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

Do, Tuan; Wright, Shelley A.; Barth, Aaron J.

2014-04-01

The next generation of giant-segmented mirror telescopes (>20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope (TMT) and the adaptive optics assisted integral-field spectrograph IRIS, which is capable of diffraction-limited spectroscopy from Z band (0.9 μm)more » to K band (2.2 μm). These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument to determine the expected signal-to-noise ratio of a range of possible targets spanning intermediate mass black holes of ∼10{sup 4} M {sub ☉} to the most massive black holes known today of >10{sup 10} M {sub ☉}. We find that IRIS will be able to observe Milky Way mass black holes out the distance of the Virgo Cluster, and will allow us to observe many more of the brightest cluster galaxies where the most massive black holes are thought to reside. We also evaluate how well the kinematic moments of the velocity distributions can be constrained at the different spectral resolutions and plate scales designed for IRIS. We find that a spectral resolution of ∼8000 will be necessary to measure the masses of intermediate mass black holes. By simulating the observations of galaxies found in Sloan Digital Sky Survey DR7, we find that over 10{sup 5} massive black holes will be observable at distances between 0.005 < z < 0.18 with the estimated sensitivity and angular resolution provided by access to Z-band (0.9 μm) spectroscopy from IRIS and the TMT adaptive optics system. These observations will provide the most accurate dynamical measurements of black hole masses to enable the study of the demography of massive black holes, address the origin of the M {sub BH} – σ and M {sub BH} – L relationships, and evolution of black holes through cosmic time.« less

Rest-Frame Mid-Infrared Detection of an Extremely Luminous Lyman Break Galaxy with the Spitzer Infrared Spectrograph (IRS)

NASA Technical Reports Server (NTRS)

Teplitz, H. I.; Charmandaris, V.; Armus, L.; Appleton, P. N.; Houck, J. R.; Soifer, B. T.; Weedman, D.; Brandl, B. R.; vanCleve, J.; Grillmair, C.;

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.

Spectroscopic Confirmation That 2MASS J07414279–0506464 Is a Mid-type L Dwarf

NASA Astrophysics Data System (ADS)

Cushing, Michael C.; Moskovitz, Nicholas; Gustafsson, Annika

2018-06-01

We present a low-resolution near-infrared spectrum of 2MASS J07414279-0506464, a mid-type L dwarf candidate recently identified by Scholz & Bell. The spectrum was obtained using the Near-Infrared High Throughput Spectrograph (NIHTS) on Lowell Observatory's 4.3 m Discovery Channel Telescope and indicates that 2MASS J07414279-0506464 has a spectral type of L5.

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.

Effects of fiber manipulation methods on optical fiber properties

NASA Astrophysics Data System (ADS)

Reynolds, Robert O.; Bechter, Andrew; Crass, Jonathan

2016-07-01

Optical fibers are routinely used to couple high-resolution spectrographs to modern telescopes, enabling important advantages in areas such as the search for extrasolar planets using spectroscopic radial velocity measurements of candidate stars. Optical fibers partially scramble the input illumination, and this feature enables a fiber feed to provide more uniform illumination to the spectrograph optics, thereby reducing systematic errors in radial velocity measurements. However fibers suffer from focal ratio degradation (FRD), a spreading of the beam at the output of the fiber with respect to that at the fiber input, which results in losses in throughput and resolution. Modal noise, a measurement uncertainty caused by inherent fiber properties and evident as a varying spatial intensity at the fiber exit plane, reduces the signal to noise ratio in the data. Devices such as double scramblers are often used to improve scrambling, and better fiber end preparation can mitigate FRD. Many instruments agitate the fiber during an observation to reduce modal noise, and stretching the fiber during use has been shown to offer a greater reduction in that noise. But effects of agitation and stretching on fiber parameters such as total transmission and focal ratio degradation have not been adequately studied. In this paper we present measurements of transmission loss and focal ratio degradation for both agitated and stretched fibers.

First results of tests on the WEAVE fibres

NASA Astrophysics Data System (ADS)

Sayède, Frédéric; Younes, Youssef; Fasola, Gilles; Dorent, Stéphane; Abrams, Don Carlos; Aguerri, J. Alphonso L.; Bonifacio, Piercarlo; Carrasco, Esperanza; Dalton, Gavin; Dee, Kevin; Laporte, Philippe; Lewis, Ian; Lhome, Emilie; Middleton, Kevin; Pragt, Johan H.; Rey, Juerg; Stuik, Remko; Trager, Scott C.; Vallenari, Antonella

2016-07-01

WEAVE is a new wide-field spectroscopy facility proposed for the prime focus of the 4.2m William Herschel Telescope. The facility comprises a new 2-degree field of view prime focus corrector with a 1000-multiplex fibre positioner, a small number of individually deployable integral field units, and a large single integral field unit. The IFUs (Integral Field Units) and the MOS (Multi Object Spectrograph) fibres can be used to feed a dual-beam spectrograph that will provide full coverage of the majority of the visible spectrum in a single exposure at a spectral resolution of 5000 or modest wavelength coverage in both arms at a resolution 20000. The instrument is expected to be on-sky by the first quarter of 2018 to provide spectroscopic sampling of the fainter end of the Gaia astrometric catalogue, chemical labeling of stars to V 17, and dedicated follow up of substantial numbers of sources from the medium deep LOFAR surveys. After a brief description of the Fibre System, we describe the fibre test bench, its calibration, and some test results. We have to verify 1920 fibres from the MOS bundles and 740 fibres from the mini-IFU bundles with the test bench. In particular, we present the Focal Ratio Degradation of a cable.

Goddard High Resolution Spectrograph Observations of Variability in the RS Canum Venaticorum System V711 Tauri (HR 1099)

NASA Technical Reports Server (NTRS)

Dempsey, Robert C.; Neff, James E.; Thorpe, Marjorie J.; Linsky, Jeffrey L.; Brown, Alexander; Cutispoto, Giuseppe; Rodono, Marcello

1996-01-01

Goddard High Resolution Spectrograph (GHRS) observations of the RS CVn-type binary V711 Tau (Kl IV+G5 IV) were obtained at several phases over two consecutive stellar orbital cycles in order to study ultraviolet emission-line profile and flux variability. Spectra cover the Mg II h and k lines, C IV doublet, and Si IV region, as well as the density-sensitive lines of C III] (1909 A) and Si III] (1892 A). IUE spectra, Extreme Ultra Violet (EUV) data, and Ultraviolet, Blue, Visual (UBV) photometry were obtained contemporaneously with the GHRS data. Variable extended wings were detected in the Mg II lines. We discuss the Mg II line profile variability using various Gaussian emission profile models. No rotational modulation of the line profiles was observed, but there were several large flares. These flares produced enhanced emission in the extended line wings, radial velocity shifts, and asymmetries in some line profiles. Nearly continuous flaring for more than 24 hr, as indicated in the IUE data, represents the most energetic and long-lived chromospheric and transition region flare ever observed with a total energy much greater than 5 x 10(exp 35) ergs. The C III] to Si III] line ratio is used to estimate the plasma density during the flares.

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

VizieR Online Data Catalog: Abundances of metal-poor star HD 94028 (Roederer+, 2016)

NASA Astrophysics Data System (ADS)

Roederer, I. U.; Karakas, A. I.; Pignatari, M.; Herwig, F.

2016-06-01

We use two NUV spectroscopic data sets of HD 94028 available in the Mikulski Archive for Space Telescopes. These observations were made using STIS on board the HST. One spectrum (data sets O5CN01-03, GO-8197, PI. Duncan) has very high spectral resolution (R~110000). This spectrum covers ~1885-2147Å with signal-to-noise ratios (S/N)35/1 per pixel near 2140Å. The other spectrum (data sets O56D06-07, GO-7402, PI. Peterson) has high spectral resolution (R~30000). This spectrum covers 2280-3117Å with S/N ranging from ~20 near 2300Å to ~40 near 3100Å. Roederer et al. (2014, J/AJ/147/136) derived abundances from an optical spectrum of HD 94028 taken using the Robert G. Tull Coude Spectrograph on the Harlan J. Smith Telescope at McDonald Observatory, Texas. We rederive abundances from this spectrum. We also use an optical spectrum taken with the Ultraviolet and Visual Echelle Spectrograph (UVES) on the Very Large Telescope (VLT) Kueyen at Cerro Paranal, Chile. We obtained this spectrum from the ESO Science Archive. This spectrum covers 3050-3860Å at R~37000 with S/N ranging from ~40 near 3200Å to ~130 near 3800Å. (3 data files).

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.

WINERED: a warm near-infrared high-resolution spectrograph

NASA Astrophysics Data System (ADS)

Ikeda, Yuji; Kobayashi, Naoto; Kondo, Sohei; Yasui, Chikako; Motohara, Kentaro; Minami, Atsushi

2006-06-01

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 the following two novel approaches in the optical system: (1) portable design with a ZnSe immersion grating and (2) warm optics without any cold stops. These concepts result in several essential advantages as follows: easy to build, align, and maintain; these result in a short development time and low cost. WINERED employs a VIRGO HgCdTe 2k × 2k array by Raytheon as the detector. We are developing our own array control system that aims at a low readout noise (< 10 e -) with a readout time of about 3 sec. Our goal is to achieve a high sensitivity of R = 100,000 for a NIR spectroscopy of 15 mag and 17 mag point sources with 4 m and 10 m telescopes, respectively. We have just finalized the optical design and produced a prototype electronics, which are described in the companion papers by Yasui et al. and Kondo et al., respectively. We plan to complete this instrument by the end of 2008 and hope to attach it to various 4 to 10 m telescopes as a PI-type instrument.

VizieR Online Data Catalog: Solar-type stars from SDSS-III MARVELS. VI. HD 87646 (Ma+, 2016)

NASA Astrophysics Data System (ADS)

Ma, B.; Ge, J.; Wolszczan, A.; Muterspaugh, M. W.; Lee, B.; Henry, G. W.; Schneider, D. P.; Martin, E. L.; Niedzielski, A.; Xie, J.; Fleming, S. W.; Thomas, N.; Williamson, M.; Zhu, Z.; Agol, E.; Bizyaev, D.; da Costa, L. N.; Jiang, P.; Fiorenzano, A. F. M.; Hernandez, J. I. G.; Guo, P.; Grieves, N.; Li, R.; Liu, J.; Mahadevan, S.; Mazeh, T.; Nguyen, D. C.; Paegert, M.; Sithajan, S.; Stassun, K.; Thirupathi, S.; van Eyken, J. C.; Wan, X.; Wang, J.; Wisniewski, J. P.; Zhao, B.; Zucker, S.

2016-11-01

We have obtained a total of 16 observations of HD87646 using the W.M. Keck Exoplanet Tracker (KeckET) from 2006 December to 2007 June. The radial velocities obtained are listed in Table1. The KeckET instrument was constructed in 2005 August-2006 February with support from the Keck Foundation. It was coupled with a wide field Sloan Digital Sky Survey telescope (SDSS) and used for the pilot Multi-Object APO RV Exoplanet Large-Area Survey (MARVELS). This is the sixth paper in this series, examining the low-mass companions around solar-type stars from the SDSS-III MARVELS survey (Wisniewski et al. 2012, Cat. J/AJ/143/107; Fleming et al. 2012AJ....144...72F; Ma et al. 2013AJ....145...20M; Jiang et al. 2013AJ....146...65J; De Lee et al. 2013AJ....145..155D). The KeckET instrument consists of eight subsystems-a multi-object fiber feed, an iodine cell, a fixed-delay interferometer system, a slit, a collimator, a grating, a camera, and a 4k*4k CCD detector. In addition, it contains four auxiliary subsystems: the interferometer control, an instrument calibration system, a photon flux monitoring system, and a thermal probe and control system. The instrument is fed with 60 fibers with 200μm core diameters, which are coupled to 180μm core diameter short fibers from the SDSS telescope, corresponding to 3arcsec on the sky at f/5. The resolving power for the spectrograph is R=5100, and the wavelength coverage is ~900Å, centered at 5400Å. KeckET has one spectrograph and one 4k*4k CCD camera that captures one of the two interferometer outputs, and has a 5.5% detection efficiency from the telescope to the detector without the iodine cell under the typical APO seeing conditions (~1.5arcsec seeing). The CCD camera records fringing spectra from 59 objects in a single exposure. Subsequent observations were performed using the Exoplanet Tracker (ET) instrument at Kitt Peak National Observatory (KPNO). Initial follow-up was performed in 2007 November. Additional data points were obtained at KPNO in 2008 January, February, and May. The integration time was 35-40 minutes in 2007 November and 20 minutes in 2008 January, February, and May. A total of 40 data points were obtained from 2007 November to 2008 May and are also listed in Table1. Follow-up observations of HD87646 were conducted with the fiber-fed High Resolution Spectrograph (HRS) of the Hobby Eberley telescope (HET). The observations were executed in queue scheduled mode and used a 2 arcsec fiber, with the HRS slit set, to yield a spectral resolution of R~60000. A total of 29 data points were obtained between 2007 December and 2008 March. The HRS spectra consisted of 46 echelle orders recorded on the blue CCD (407-592nm) and 24 orders on the red one (602-784nm). The spectral data used for RV measurements were extracted from the 17 orders (505-592nm) in which the I2 cell superimposed strong absorption lines. The radial velocities obtained are also provided in Table1. HD87646 was selected as an radial velocity survey target by the Multi-object APO RV Exoplanet Large-area Survey (MARVELS) preselection criterion. The star has been monitored at 23 epochs using the MARVELS instrument mounted on the SDSS 2.5m Telescope at APO between 2009 May and 2011 December. The MARVELS instrument is a fiber-fed dispersed fixed-delay interferometer instrument capable of observing 60 objects simultaneously and covers a wavelength range of 5000-5700Å with a resolution of R~12000. The final differential radial velocity products are included in the SDSS Data Release 12 (Alam et al. 2015ApJS..219...12A) and are presented in Table1. We have obtained additional observations of HD87646 with a fiber-fed echelle spectrograph situated at the 2m Automatic Spectroscopic Telescope (AST) in the Fairborn Observatory. Through 2011 June, the detector was a 2048*4096 SITe ST-002A CCD with 15μm pixels. The AST echelle spectrograph has 21 orders that cover the wavelength range of 4920-7100Å, and has an average resolution of 0.17Å. In the summer of 2011, the SITe CCD detector and dewar were replaced with a Fairchild 486 CCD having 4K*4K 15μm pixels, which required a new readout electronics package, and a new dewar with a Cryotiger refrigeration system. The echelle spectrograms that were obtained with this new detector have 48 orders, covering the wavelength range of 3800-8260Å. A total of 135 data points were obtained from 2009 March through 2013 October and are listed in Table1. (1 data file).

sCMOS detector for imaging VNIR spectrometry

NASA Astrophysics Data System (ADS)

Eckardt, Andreas; Reulke, Ralf; Schwarzer, Horst; Venus, Holger; Neumann, Christian

2013-09-01

The facility Optical Information Systems (OS) at the Robotics and Mechatronics Center of the German Aerospace Center (DLR) has more than 30 years of experience with high-resolution imaging technology. This paper shows the scientific results of the institute of leading edge instruments and focal plane designs for EnMAP VIS/NIR spectrograph. EnMAP (Environmental Mapping and Analysis Program) is one of the selected proposals for the national German Space Program. The EnMAP project includes the technological design of the hyper spectral space borne instrument and the algorithms development of the classification. The EnMAP project is a joint response of German Earth observation research institutions, value-added resellers and the German space industry like Kayser-Threde GmbH (KT) and others to the increasing demand on information about the status of our environment. The Geo Forschungs Zentrum (GFZ) Potsdam is the Principal Investigator of EnMAP. DLR OS and KT were driving the technology of new detectors and the FPA design for this project, new manufacturing accuracy and on-chip processing capability in order to keep pace with the ambitious scientific and user requirements. In combination with the engineering research, the current generations of space borne sensor systems are focusing on VIS/NIR high spectral resolution to meet the requirements on earth and planetary observation systems. The combination of large swath and high spectral resolution with intelligent synchronization control, fast-readout ADC chains and new focal-plane concepts open the door to new remote-sensing and smart deep space instruments. The paper gives an overview over the detector verification program at DLR on FPA level, new control possibilities for sCMOS detectors in global shutter mode and key parameters like PRNU, DSNU, MTF, SNR, Linearity, Spectral Response, Quantum Efficiency, Flatness and Radiation Tolerance will be discussed in detail.

Suppression of the near-infrared OH night-sky lines with fibre Bragg gratings - first results

NASA Astrophysics Data System (ADS)

Ellis, S. C.; Bland-Hawthorn, J.; Lawrence, J.; Horton, A. J.; Trinh, C.; Leon-Saval, S. G.; Shortridge, K.; Bryant, J.; Case, S.; Colless, M.; Couch, W.; Freeman, K.; Gers, L.; Glazebrook, K.; Haynes, R.; Lee, S.; Löhmannsröben, H.-G.; O'Byrne, J.; Miziarski, S.; Roth, M.; Schmidt, B.; Tinney, C. G.; Zheng, J.

2012-09-01

The background noise between 1 and 1.8 μm in ground-based instruments is dominated by atmospheric emission from hydroxyl molecules. We have built and commissioned a new instrument, the Gemini Near-infrared OH Suppression Integral Field Unit (IFU) System (GNOSIS), which suppresses 103 OH doublets between 1.47 and 1.7 μm by a factor of ≈1000 with a resolving power of ≈10 000. We present the first results from the commissioning of GNOSIS using the IRIS2 spectrograph at the Anglo-Australian Telescope. We present measurements of sensitivity, background and throughput. The combined throughput of the GNOSIS fore-optics, grating unit and relay optics is ≈36 per cent, but this could be improved to ≈46 per cent with a more optimal design. We measure strong suppression of the OH lines, confirming that OH suppression with fibre Bragg gratings will be a powerful technology for low-resolution spectroscopy. The integrated OH suppressed background between 1.5 and 1.7 μm is reduced by a factor of 9 compared to a control spectrum using the same system without suppression. The potential of low-resolution OH-suppressed spectroscopy is illustrated with example observations of Seyfert galaxies and a low-mass star. The GNOSIS background is dominated by detector dark current below 1.67 μm and by thermal emission above 1.67 μm. After subtracting these, we detect an unidentified residual interline component of ≈860 ± 210 photons s-1 m-2 arcsec-2 μm-1, comparable to previous measurements. This component is equally bright in the suppressed and control spectra. We have investigated the possible source of the interline component, but were unable to discriminate between a possible instrumental artefact and intrinsic atmospheric emission. Resolving the source of this emission is crucial for the design of fully optimized OH suppression spectrographs. The next-generation OH suppression spectrograph will be focused on resolving the source of the interline component, taking advantage of better optimization for a fibre Bragg grating feed incorporating refinements of design based on our findings from GNOSIS. We quantify the necessary improvements for an optimal OH suppressing fibre spectrograph design.

Metrology measurements for large-aperture VPH gratings

NASA Astrophysics Data System (ADS)

Zheng, Jessica R.; Gers, Luke; Heijmans, Jeroen

2013-09-01

The High Efficiency and Resolution Multi Element Spectrograph (HERMES) for the Australian Astronomical Observatory (AAO) uses four large aperture, high angle of incidence volume phase holographic gratings (VPHG) for high resolution `Galactic archaeology' spectroscopy. The large clear aperture, the high diffraction efficiency, the line frequency homogeneity, and mosaic alignment made manufacturing and testing challenging. We developed new metrology systems at the AAO to verify the performance of these VPH gratings. The measured diffraction efficiencies and line frequency of the VPH gratings received so far meet the vendor's provided data. The wavefront quality for the Blue VPH grating is good but the Green and Red VPH gratings need to be post polishing.

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.

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.

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.

Li depletion in solar analogues with exoplanets. Extending the sample

NASA Astrophysics Data System (ADS)

Delgado Mena, E.; Israelian, G.; González Hernández, J. I.; Sousa, S. G.; Mortier, A.; Santos, N. C.; Adibekyan, V. Zh.; Fernandes, J.; Rebolo, R.; Udry, S.; Mayor, M.

2014-02-01

Aims: We want to study the effects of the formation of planets and planetary systems on the atmospheric Li abundance of planet host stars. Methods: In this work we present new determinations of lithium abundances for 326 main sequence stars with and without planets in the Teff range 5600-5900 K. The 277 stars come from the HARPS sample, the remaining targets were observed with a variety of high-resolution spectrographs. Results: We confirm significant differences in the Li distribution of solar twins (Teff = T⊙ ± 80 K, log g = log g⊙ ± 0.2 and [Fe/H] = [Fe/H]⊙ ± 0.2): the full sample of planet host stars (22) shows Li average values lower than "single" stars with no detected planets (60). If we focus on subsamples with narrower ranges in metallicity and age, we observe indications of a similar result though it is not so clear for some of the subsamples. Furthermore, we compare the observed spectra of several couples of stars with very similar parameters that show differences in Li abundances up to 1.6 dex. Therefore we show that neither age, mass, nor metallicity of a parent star is the only cause for enhanced Li depletion in solar analogues. Conclusions: We conclude that another variable must account for that difference and suggest that this could be the presence of planets that causes additional rotationally induced mixing in the external layers of planet host stars. Moreover, we find indications that the amount of depletion of Li in planet-host solar-type stars is higher when the planets are more massive than Jupiter. Based on observations collected at the La Silla Observatory, ESO (Chile), with the HARPS spectrograph at the 3.6 m ESO telescope, with CORALIE spectrograph at the 1.2 m Euler Swiss telescope and with the FEROS spectrograph at the 1.52 m ESO telescope; at the Paranal Observatory, ESO (Chile), using the UVES spectrograph at the VLT/UT2 Kueyen telescope, and with the FIES, SARG, and UES spectrographs at the 2.5 m NOT, the 3.6 m TNG and the 4.2 WHT, respectively, operated on the island of La Palma in the Spanish Observatorio del Roque de los Muchachos.Table 6 is available in electronic form at http://www.aanda.org

CARMENES-NIR channel spectrograph cooling system AIV: thermo-mechanical performance of the instrument

NASA Astrophysics Data System (ADS)

Becerril, S.; Mirabet, E.; Lizon, J. L.; Abril, M.; Cárdenas, C.; Ferro, I.; Morales, R.; Pérez, D.; Ramón, A.; Sánchez-Carrasco, M. A.; Quirrenbach, A.; Amado, P.; Ribas, I.; Reiners, A.; Caballero, J. A.; Seifert, W.; Herranz, J.

2016-07-01

CARMENES is the new high-resolution high-stability spectrograph built for the 3.5m telescope at the Calar Alto Observatory (CAHA, Almería, Spain) by a consortium formed by German and Spanish institutions. This instrument is composed by two separated spectrographs: VIS channel (550-1050 nm) and NIR channel (950- 1700 nm). The NIR-channel spectrograph's responsible is the Instituto de Astrofísica de Andalucía (IAACSIC). It has been manufactured, assembled, integrated and verified in the last two years, delivered in fall 2015 and commissioned in December 2015. One of the most challenging systems in this cryogenic channel involves the Cooling System. Due to the highly demanding requirements applicable in terms of stability, this system arises as one of the core systems to provide outstanding stability to the channel. Really at the edge of the state-of-the-art, the Cooling System is able to provide to the cold mass ( 1 Ton) better thermal stability than few hundredths of degree within 24 hours (goal: 0.01K/day). The present paper describes the Assembly, Integration and Verification phase (AIV) of the CARMENES-NIR channel Cooling System implemented at IAA-CSIC and later installation at CAHA 3.5m Telescope, thus the most relevant highlights being shown in terms of thermal performance. The CARMENES NIR-channel Cooling System has been implemented by the IAA-CSIC through very fruitful collaboration and involvement of the ESO (European Southern Observatory) cryo-vacuum department with Jean-Louis Lizon as its head and main collaborator. The present work sets an important trend in terms of cryogenic systems for future E-ELT (European Extremely Large Telescope) large-dimensioned instrumentation in astrophysics.

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).

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.

Integration, commissioning, and performance of the UK FMOS spectrograph

NASA Astrophysics Data System (ADS)

Dalton, Gavin B.; Lewis, Ian J.; Tosh, Ian A. J.; Blackburn, Colin; Bonfield, David G.; Brooks, Charles B.; Holmes, Alan R.; Lee, Hanshin; Froud, Tim R.; Akiyama, Masayuki; Tamura, Naoyuki; Takato, Naruhisa

2008-07-01

The UK FMOS spectrograph forms part of Subaru's FMOS multi-object infrared spectroscopy facility. The spectrograph was shipped to Hilo in component form in August of 2007. We describe the integration sequence for the spectrograph, the results of cooldown tests using a new chiller unit fitted to the spectrograph at the telescope, and alignment tests of the spectrograph, gratings and OH-suppression masks. We present the first-light observations for the spectrograph from May 2008.

High sensitivity, wide coverage, and high-resolution NIR non-cryogenic spectrograph, WINERED

NASA Astrophysics Data System (ADS)

Ikeda, Yuji; Kobayashi, Naoto; Kondo, Sohei; Otsubo, Shogo; Hamano, Satoshi; Sameshima, Hiroaki; Yoshikawa, Tomoshiro; Fukue, Kei; Nakanishi, Kenshi; Kawanishi, Takafumi; Nakaoka, Tetsuya; Kinoshita, Masaomi; Kitano, Ayaka; Asano, Akira; Takenaka, Keiichi; Watase, Ayaka; Mito, Hiroyuki; Yasui, Chikako; Minami, Atsushi; Izumu, Natsuko; Yamamoto, Ryo; Mizumoto, Misaki; Arasaki, Takayuki; Arai, Akira; Matsunaga, Noriyuki; Kawakita, Hideyo

2016-08-01

Near-infrared (NIR) high-resolution spectroscopy is a fundamental observational method in astronomy. It provides significant information on the kinematics, the magnetic fields, and the chemical abundances, of astronomical objects embedded in or behind the highly extinctive clouds or at the cosmological distances. Scientific requirements have accelerated the development of the technology required for NIR high resolution spectrographs using 10 m telescopes. WINERED is a near-infrared (NIR) high-resolution spectrograph that is currently mounted on the 1.3 m Araki telescope of the Koyama Astronomical Observatory in Kyoto-Sangyo University, Japan, and has been successfully operated for three years. It covers a wide wavelength range from 0.90 to 1.35 μm (the z-, Y-, and J-bands) with a spectral resolution of R = 28,000 (Wide-mode) and R = 80,000 (Hires-Y and Hires-J modes). WINERED has three distinctive features: (i) optics with no cold stop, (ii) wide spectral coverage, and (iii) high sensitivity. The first feature, originating from the Joyce proposal, was first achieved by WINERED, with a short cutoff infrared array, cold baffles, and custom-made thermal blocking filters, and resulted in reducing the time for development, alignment, and maintenance, as well as the total cost. The second feature is realized with the spectral coverage of Δλ/λ 1/6 in a single exposure. This wide coverage is realized by a combination of a decent optical design with a cross-dispersed echelle and a large format array (2k x 2k HAWAII- 2RG). The Third feature, high sensitivity, is achieved via the high-throughput optics (>60 %) and the very low noise of the system. The major factors affecting the high throughput are the echelle grating and the VPH cross-disperser with high diffraction efficiencies of 83 % and 86 %, respectively, and the high QE of HAWAII-2RG (83 % at 1.23 μm). The readout noise of the electronics and the ambient thermal background radiation at longer wavelengths could be major noise sources. The readout noise is 5.3 e- for NDR = 32, and the ambient thermal background is significantly reduced to 0.05 e- pix-1 sec-1 at 273 K. As a result, the limiting magnitudes of WINERED are estimated to be mJ = 13.8 mag for the 1.3 m telescope, mJ = 16.9 mag for the 3.6 m telescope, and mJ = 19.2 mag for 10 m telescope with adoptive optics, respectively. Finally, we introduce some scientific highlights provided by WINERED for both emission and absorption line objects in the fields of stars, the interstellar medium, and the solar system.

K-line spectra from tungsten heated by an intense pulsed electron beam.

PubMed

Pereira, N R; Weber, B V; Apruzese, J P; Mosher, D; Schumer, J W; Seely, J F; Szabo, C I; Boyer, C N; Stephanakis, S J; Hudson, L T

2010-10-01

The plasma-filled rod-pinch diode (PFRP) is an intense source of x-rays ideal for radiography of dense objects. In the PRFP megavoltage electrons from a pulsed discharge concentrate at the pointed end of a 1 mm diameter tapered tungsten rod. Ionization of this plasma might increase the energy of tungsten's Kα(1) fluorescence line, at 59.3182 keV, enough for the difference to be observed by a high-resolution Cauchois transmission crystal spectrograph. When the PFRP's intense hard bremsstrahlung is suppressed by the proper shielding, such an instrument gives excellent fluorescence spectra, albeit with as yet insufficient resolution to see any effect of tungsten's ionization. Higher resolution is possible with various straightforward upgrades that are feasible thanks to the radiation's high intensity.

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.

AIRES: An Airborne Infra-Red Echelle Spectrometer for SOFIA

NASA Technical Reports Server (NTRS)

Dotson, Jessie J.; Erickson, Edwin F.; Haas, Michael R.; Colgan, Sean W. J.; Simpson, Janet P.; Telesco, Charles M.; Pina, Robert K.; Wolf, Juergen; Young, Erick T.

1999-01-01

SOFIA will enable astronomical observations with unprecedented angular resolution at infrared wavelengths obscured from the ground. To help open this new chapter in the exploration of the infrared universe, we are building AIRES, an Airborne Infra-Red Echelle Spectrometer. AIRES will be operated as a first generation, general purpose facility instrument by USRA, NASA's prime contractor for SOFIA. AIRES is a long slit spectrograph operating from 17 - 210 microns. In high resolution mode the spectral resolving power is approx. 10(exp 6) microns/A or approx. 10(exp 4) at 100 microns. Unfortunately, since the conference, a low resolution mode with resolving power about 100 times lower has been deleted due to budgetary constraints. AIRES includes a slit viewing camera which operates in broad bands at 18 and 25 microns.

VizieR Online Data Catalog: Detailed abundances of KOI stars with planets. I. (Schuler+, 2015)

NASA Astrophysics Data System (ADS)

Schuler, S. C.; Vaz, Z. A.; Katime Santrich, O. J.; Cunha, K.; Smith, V. V.; King, J. R.; Teske, J. K.; Ghezzi, L.; Howell, S. B.; Isaacson, H.

2016-03-01

We have analyzed high-resolution, high-signal-to-noise ratio (S/N) spectra of seven stars, each of which has at least one confirmed small planet discovered by Kepler. The spectra of these stars were obtained as part of the Kepler Follow-up Observing Program (KFOP). The 10m Keck I telescope and High Resolution Echelle Spectrometer (HIRES) are being utilized for precise RV measurements of high-priority KOIs. The KFOP spectra are characterized by a spectral resolution of R=50000 and span 3650-7950Å with incomplete coverage in the reddest orders. Additional observations of Kepler-21 were made independently with Keck/HIRES and the 4m Mayall telescope and echelle spectrograph at Kitt Peak National Observatory (KPNO) in UT 2011. (4 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.

LRG-BEASTS III: ground-based transmission spectrum of the gas giant orbiting the cool dwarf WASP-80

NASA Astrophysics Data System (ADS)

Kirk, J.; Wheatley, P. J.; Louden, T.; Skillen, I.; King, G. W.; McCormac, J.; Irwin, P. G. J.

2018-02-01

We have performed ground-based transmission spectroscopy of the hot Jupiter orbiting the cool dwarf WASP-80 using the ACAM instrument on the William Herschel Telescope (WHT) as part of the Low-Resolution Ground-Based Exoplanet Atmosphere Survey using Transmission Spectroscopy programme. This is the third paper of a ground-based transmission spectroscopy survey of hot Jupiters using low-resolution grism spectrographs. We observed two transits of the planet and have constructed transmission spectra spanning a wavelength range of 4640-8840 Å. Our transmission spectrum is inconsistent with a previously claimed detection of potassium in WASP-80b's atmosphere, and is instead most consistent with a haze. We also do not see evidence for sodium absorption at a resolution of 100 Å.

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

High-resolution broadband spectroscopy using externally dispersed interferometry at the Hale telescope: Part 1, data analysis and results

NASA Astrophysics Data System (ADS)

Erskine, David J.; Edelstein, Jerry; Wishnow, Edward H.; Sirk, Martin; Muirhead, Philip S.; Muterspaugh, Matthew W.; Lloyd, James P.; Ishikawa, Yuzo; McDonald, Eliza A.; Shourt, William V.; Vanderburg, Andrew M.

2016-04-01

High-resolution broadband spectroscopy at near-infrared wavelengths (950 to 2450 nm) has been performed using externally dispersed interferometry (EDI) at the Hale telescope at Mt. Palomar. Observations of stars were performed with the "TEDI" interferometer mounted within the central hole of the 200-in. primary mirror in series with the comounted TripleSpec near-infrared echelle spectrograph. These are the first multidelay EDI demonstrations on starlight, as earlier measurements used a single delay or laboratory sources. We demonstrate very high (10×) resolution boost, from original 2700 to 27,000 with current set of delays (up to 3 cm), well beyond the classical limits enforced by the slit width and detector pixel Nyquist limit. Significantly, the EDI used with multiple delays rather than a single delay as used previously yields an order of magnitude or more improvement in the stability against native spectrograph point spread function (PSF) drifts along the dispersion direction. We observe a dramatic (20×) reduction in sensitivity to PSF shift using our standard processing. A recently realized method of further reducing the PSF shift sensitivity to zero is described theoretically and demonstrated in a simple simulation which produces a 350× times reduction. We demonstrate superb rejection of fixed pattern noise due to bad detector pixels-EDI only responds to changes in pixel intensity synchronous to applied dithering. This part 1 describes data analysis, results, and instrument noise. A section on theoretical photon limited sensitivity is in a companion paper, part 2.

High-resolution broadband spectroscopy using externally dispersed interferometry at the Hale telescope: Part 1, data analysis and results

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

Erskine, David J.; Edelstein, Jerry; Wishnow, Edward H.

High-resolution broadband spectroscopy at near-infrared wavelengths (950 to 2450 nm) has been performed using externally dispersed interferometry (EDI) at the Hale telescope at Mt. Palomar. Observations of stars were performed with the “TEDI” interferometer mounted within the central hole of the 200-in. primary mirror in series with the comounted TripleSpec near-infrared echelle spectrograph. These are the first multidelay EDI demonstrations on starlight, as earlier measurements used a single delay or laboratory sources. We demonstrate very high (10×) resolution boost, from original 2700 to 27,000 with current set of delays (up to 3 cm), well beyond the classical limits enforced bymore » the slit width and detector pixel Nyquist limit. Significantly, the EDI used with multiple delays rather than a single delay as used previously yields an order of magnitude or more improvement in the stability against native spectrograph point spread function (PSF) drifts along the dispersion direction. We observe a dramatic (20×) reduction in sensitivity to PSF shift using our standard processing. A recently realized method of further reducing the PSF shift sensitivity to zero is described theoretically and demonstrated in a simple simulation which produces a 350× times reduction. We demonstrate superb rejection of fixed pattern noise due to bad detector pixels—EDI only responds to changes in pixel intensity synchronous to applied dithering. This part 1 describes data analysis, results, and instrument noise. Lastly, a section on theoretical photon limited sensitivity is in a companion paper, part 2.« less

High-resolution broadband spectroscopy using externally dispersed interferometry at the Hale telescope: Part 1, data analysis and results

DOE PAGES

Erskine, David J.; Edelstein, Jerry; Wishnow, Edward H.; ...

2016-05-27

High-resolution broadband spectroscopy at near-infrared wavelengths (950 to 2450 nm) has been performed using externally dispersed interferometry (EDI) at the Hale telescope at Mt. Palomar. Observations of stars were performed with the “TEDI” interferometer mounted within the central hole of the 200-in. primary mirror in series with the comounted TripleSpec near-infrared echelle spectrograph. These are the first multidelay EDI demonstrations on starlight, as earlier measurements used a single delay or laboratory sources. We demonstrate very high (10×) resolution boost, from original 2700 to 27,000 with current set of delays (up to 3 cm), well beyond the classical limits enforced bymore » the slit width and detector pixel Nyquist limit. Significantly, the EDI used with multiple delays rather than a single delay as used previously yields an order of magnitude or more improvement in the stability against native spectrograph point spread function (PSF) drifts along the dispersion direction. We observe a dramatic (20×) reduction in sensitivity to PSF shift using our standard processing. A recently realized method of further reducing the PSF shift sensitivity to zero is described theoretically and demonstrated in a simple simulation which produces a 350× times reduction. We demonstrate superb rejection of fixed pattern noise due to bad detector pixels—EDI only responds to changes in pixel intensity synchronous to applied dithering. This part 1 describes data analysis, results, and instrument noise. Lastly, a section on theoretical photon limited sensitivity is in a companion paper, part 2.« less

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.

BATMAN: MOS Spectroscopy on Demand

NASA Astrophysics Data System (ADS)

Molinari, E.; Zamkotsian, F.; Moschetti, M.; Spano, P.; Boschin, W.; Cosentino, R.; Ghedina, A.; González, M.; Pérez, H.; Lanzoni, P.; Ramarijaona, H.; Riva, M.; Zerbi, F.; Nicastro, L.; Valenziano, L.; Di Marcantonio, P.; Coretti, I.; Cirami, R.

2016-10-01

Multi-Object Spectrographs (MOS) are the major instruments for studying primary galaxies and remote and faint objects. Current object selection systems are limited and/or difficult to implement in next generation MOS for space and ground-based telescopes. A promising solution is the use of MOEMS devices such as micromirror arrays, which allow the remote control of the multi-slit configuration in real time. TNG is hosting a novelty project for real-time, on-demand MOS masks based on MOEMS programmable slits. We are developing a 2048×1080 Digital-Micromirror-Device-based (DMD) MOS instrument to be mounted on the Galileo telescope, called BATMAN. It is a two-arm instrument designed for providing in parallel imaging and spectroscopic capabilities. With a field of view of 6.8×3.6 arcmin and a plate scale of 0.2 arcsec per micromirror, this astronomical setup can be used to investigate the formation and evolution of galaxies. The wavelength range is in the visible and the spectral resolution is R=560 for a 1 arcsec object, and the two arms will have 2k × 4k CCD detectors. ROBIN, a BATMAN demonstrator, has been designed, realized and integrated. We plan to have BATMAN first light by mid-2016.

Implementation of the control electronics for KMOS instrument

NASA Astrophysics Data System (ADS)

Hess, Hans-Joachim; Ilijevski, Ivica; Kravcar, Helmut; Richter, Josef; Rühfel, Josef; Schwab, Christoph

2010-07-01

The KMOS Instrument is built to be one of the second generation VLT instruments. It is a highly complex multi-object spectrograph for the near infrared. Nearly 60 cryogenic mechanisms have to be controlled. This includes 24 deployable Pick-Off arms, three filter and grating wheels as well as three focus stages and four lamps with an attenuator wheel. These mechanisms and a calibration unit are supervised by three control cabinets based on the VLT standards. To follow the rotation of the Nasmyth adaptor the cabinets are mounted into a Co-rotating structure. The presentation will highlight the requirements on the electronics control and how these are met by new technologies applying a compact and reliable signal distribution. To enable high density wiring within the given space envelope flex-rigid printed circuit board designs have been installed. In addition an electronic system that detects collisions between the moving Pick-Off arms will be presented for safe operations. The control system is designed to achieve two micron resolution as required by optomechanical and flexure constraints. Dedicated LVDT sensors are capable to identify the absolute positions of the Pick- Off arms. These contribute to a safe recovery procedure after power failure or accidental collision.

The Warm-Hot Intergalactic Medium Explorer (WHIMex) Mission Concept

NASA Astrophysics Data System (ADS)

Lillie, Charles F.; Cash, W. C.; McEntaffer, R. L.; Zhang, W.; O'Dell, S.; Bautz, M.; Elvis, M.

2011-05-01

WHIMEx is a low-cost, highly capable, single instrument X-ray observatory proposed as a NASA Explorer 2011 mission. WHIMEx will use high resolution X-ray spectroscopy (R ≥ 4000) to probe the hot, tenuous gas that populates the great stretches between the galaxies - the place where most of the baryons in the Universe reside. The bulk of this gas is so hot that it can only be studied in the soft X-ray region where the atomic diagnostics for highly ionized species reside. And this gas is so tenuous that it can only be observed in absorption. To detect the absorption lines of O VII and O VIII along the line of sight to distant AGN requires an order of magnitude improvement in both spectral resolution and collecting area over the current best X-ray spectrographs on Chandra and XMM-Newton. WHIMEx achieves this goal in a compact and affordable package through the application of technologies that were developed over the last decade for the International X-ray Observatory. WHIMex uses ultra-thin, light, densely nested parabolic-hyperbolic mirror pairs to create a telescope with a high collecting area and 15 arcsecond resolution. The X-ray beam is dispersed in wavelength by an array of radial gratings in the extreme off-plane mount. Spectral resolving power of 4000 (λ/δλ) is expected in the 0.15 to 2keV band to bring weak absorption lines out of the noise. A collecting area up to 360 cm2 will enable spectral observations of high red shift AGNs.If selected WHIMEx could be launched in mid- 2017 on a Taurus or Athena II from Vandenberg AFB into its 540 km, 70° inclination low earth orbit. In flight, it would open up a new field of exploration with high resolution observations of AGN outflows, the IGM, interstellar medium, mass transfer binaries, stellar coronae and much more

The Warm-Hot Intergalactic Medium Explorer (WHIMex)

NASA Astrophysics Data System (ADS)

Lillie, Charles F.; Cash, W. C.; Science, WHIMex; Instrument Teams

2011-09-01

WHIMex is a low-cost, highly capable, single instrument X-ray observatory proposed as a NASA Explorer 2011 mission. WHIMex will use high resolution X-ray spectroscopy (R ≥ 4000) to probe the hot, tenuous gas that populates the great stretches between the galaxies - the place where most of the baryons in the Universe reside. The bulk of this gas is so hot that it can only be studied in the soft X-ray region where the atomic diagnostics for highly ionized species reside. And this gas is so tenuous that it can only be observed in absorption. To detect the absorption lines of O VII and O VIII along the line of sight to distant AGN requires an order of magnitude improvement in both spectral resolution and collecting area over the current best X-ray spectrographs on Chandra and XMM-Newton. WHIMex achieves this goal in a compact and affordable package through the application of technologies that were developed over the last decade for the International X-ray Observatory. WHIMex uses ultra-thin, light, densely nested parabolic-hyperbolic mirror pairs to create a telescope with a high collecting area and <15 arcsecond resolution. The X-ray s are dispersed in wavelength by an array of radial gratings in the extreme off-plane mount. Spectral resolving power of 4000 (λ/δλ) is expected in the 0.3 to 0.8 keV band to bring weak absorption lines out of the noise. A collecting area up to 360 cm2 will enable spectral observations of high red shift AGNs. If selected WHIMex could be launched in mid- 2017 on a Taurus or Athena II from Vandenberg AFB into a 540 km, 70° inclination low earth orbit. In flight, it would open a new field of exploration with high resolution observations of AGN outflows, the IGM, Interstellar Medium, mass transfer binaries, stellar coronae and much more.

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).