The Experts below are selected from a list of 18474 Experts worldwide ranked by ideXlab platform
Bruce E Woodgate - One of the best experts on this subject based on the ideXlab platform.
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Performance of the space telescope Imaging Spectrograph
AIP Conference Proceedings, 2008Co-Authors: Charles W. Bowers, Theodore R. Gull, Bruce E Woodgate, R. A. Kimble, Steven B. Kraemer, Mary Elizabeth Kaiser, Don Lindler, Sara R. Heap, Anthony C. Danks, P. PlaitAbstract:The Space Telescope Imaging Spectrograph (STIS) was installed aboard the Hubble Space Telescope (HST) in February, 1997. STIS operates from the ultraviolet to the near infrared (115–1000 nm) in a variety of spectroscopic and Imaging modes. Orbital characterization of STIS performance is currently underway and some of the initial results are presented here.
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Removing the Fringes from Space Telescope Imaging Spectrograph Slitless Spectra
Publications of the Astronomical Society of the Pacific, 2003Co-Authors: Eliot M. Malumuth, Bruce E Woodgate, Charles W. Bowers, R. A. Kimble, P. Plait, Don Lindler, Robert S. Hill, Ted Gull, Morley M. BloukeAbstract:ABSTRACT Using what is known about the physical and chemical structure of the CCD detector on the Space Telescope Imaging Spectrograph (STIS) and over 50 calibration images taken with different wavelength mappings onto the detector, we have devised a model function that allows us to predict the fringing of any spectral image taken with the STIS CCD. This function is especially useful for spectra taken without a slit with the G750L grating. The STIS parallel observing program uses this “slitless spectroscopy” mode extensively. The arbitrary mapping of wavelength versus position that results from each source's chance position in the field renders direct calibration of the fringe amplitudes in this mode impossible. However, we find that correcting observed data using our semiempirical fringing model produces a substantial reduction in the fringe amplitudes. Tests using the flux calibration white dwarf standard G191‐B2B show that we can reduce the fringe amplitude in the 9000–10000 A region from about 20% pea...
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Coronagraphic Imaging with the Hubble Space Telescope and the Space Telescope Imaging Spectrograph
Publications of the Astronomical Society of the Pacific, 2003Co-Authors: Carol A. Grady, Theodore R. Gull, Bruce E Woodgate, Charles W. Bowers, R. A. Kimble, Don Lindler, Sara R. Heap, Eliot M. Malumuth, Charles R. Proffitt, P. PlaitAbstract:ABSTRACT The unfiltered Space Telescope Imaging Spectrograph (STIS) CCD in tandem with focal plane wedges and a Lyot stop provides a simple white‐light coronagraph with a bandpass of 0.2–1.0 μm, which has been used since late 1998 to image nebulosity around stars in the ranges \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $0.34\leq V\leq 14$ \end{document} and \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \use...
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Space Telescope Imaging Spectrograph Coronagraphic Observations of β Pictoris
The Astrophysical Journal, 2000Co-Authors: Sara R. Heap, Don Lindler, Thierry Lanz, Robert H. Cornett, Ivan Hubeny, Stephen P. Maran, Bruce E WoodgateAbstract:We present new coronagraphic images of β Pictoris obtained with the Space Telescope Imaging Spectrograph (STIS) in 1997 September. The high-resolution images (01) clearly detect the circumstellar disk as close to the star as 075, corresponding to a projected radius of 15 AU. The images define the warp in the disk with greater precision and at closer radii to β Pic than do previous observations. They show that the warp can be modeled by the projection of two components: the main disk and a fainter component, which is inclined to the main component by 4°-5° and extends only as far as ≈4'' from the star. We interpret the main component as arising primarily in the outer disk and the tilted component as defining the inner region of the disk. The observed properties of the warped inner disk are inconsistent with a driving force from stellar radiation. However, warping induced by the gravitational potential of one or more planets is consistent with the data. Using models of planet-warped disks constructed by Larwood & Papaloizou, we derive possible masses of the perturbing object.
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Hubble Space Telescope Space Telescope Imaging Spectrograph Coronagraphic Imaging of the Herbig Ae Star AB Aurigae
The Astrophysical Journal, 1999Co-Authors: Carol A. Grady, Bruce E Woodgate, P. Plait, A. Boggess, Mark Clampin, Frederick C. Bruhweiler, Don Lindler, Paul KalasAbstract:We present the first broadband, coronagraphic Hubble Space Telescope images of the bright, optically visible, isolated Herbig Ae star AB Aurigae. The Space Telescope Imaging Spectrograph (STIS) images reveal extended circumstellar nebulosity (r ≈ 1300 AU) covering the region of the millimeter continuum and CO disk. The structure is observed in the disk on spatial scales down to 01 (14 AU) and exhibits a north-south asymmetry. A comparison of the STIS data with scattering models for flared disks or disks + envelopes suggests that the disk inclination is i ≤ 45° from the plane of the sky.
J.-p. Wülser - One of the best experts on this subject based on the ideXlab platform.
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Instrument Calibration of the Interface Region Imaging Spectrograph (IRIS) Mission
Solar Physics, 2018Co-Authors: J.-p. Wülser, Bart De Pontieu, S. Jaeggli, S. Freeland, R. Timmons, Sian Brannon, C. Kankelborg, Theodore Tarbell, P Boerner, C. MadsenAbstract:The Interface Region Imaging Spectrograph (IRIS) is a NASA small explorer mission that provides high-resolution spectra and images of the Sun in the 133 – 141 nm and 278 – 283 nm wavelength bands. The IRIS data are archived in calibrated form and made available to the public within seven days of observing. The calibrations applied to the data include dark correction, scattered light and background correction, flat fielding, geometric distortion correction, and wavelength calibration. In addition, the IRIS team has calibrated the IRIS absolute throughput as a function of wavelength and has been tracking throughput changes over the course of the mission. As a resource for the IRIS data user, this article describes the details of these calibrations as they have evolved over the first few years of the mission. References to online documentation provide access to additional information and future updates.
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An on Orbit Determination of Point Spread Functions for the Interface Region Imaging Spectrograph
Solar Physics, 2018Co-Authors: Hans Courrier, Bart De Pontieu, C. Kankelborg, J.-p. WülserAbstract:Using the 2016 Mercury transit of the Sun, we characterize on orbit spatial point spread functions (PSFs) for the Near- (NUV) and Far- (FUV) Ultra-Violet Spectrograph channels of NASA’s Interface Region Imaging Spectrograph (IRIS). A semi-blind Richardson–Lucy deconvolution method is used to estimate PSFs for each channel. Corresponding estimates of Modulation Transfer Functions (MTFs) indicate resolution of 2.47 cycles/arcsec in the NUV channel near 2796 Å and 2.55 cycles/arcsec near 2814 Å. In the short ( ≈ 1336 Å ${\approx}\,1336~\mathring{\mathrm{A}}$ ) and long ( ≈ 1394 Å ${\approx}\,1394~\mathring{\mathrm{A}}$ ) wavelength FUV channels, our MTFs show pixel-limited resolution (3.0 cycles/arcsec). The PSF estimates perform well under deconvolution, removing or significantly reducing instrument artifacts in the Mercury transit spectra. The usefulness of the PSFs is demonstrated in a case study of an isolated explosive event. PSF estimates and deconvolution routines are provided through a SolarSoft module.
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An Interface Region Imaging Spectrograph First View on Solar Spicules
The Astrophysical Journal, 2014Co-Authors: T M D Pereira, James R. Lemen, Bart De Pontieu, A M Title, P Boerner, Theodore D. Tarbell, M Carlsson, V H Hansteen, N E Hurlburt, J.-p. WülserAbstract:Solar spicules have eluded modelers and observers for decades. Since the discovery of the more energetic type II, spicules have become a heated topic but their contribution to the energy balance of the low solar atmosphere remains unknown. Here we give a first glimpse of what quiet-Sun spicules look like when observed with NASA's recently launched Interface Region Imaging Spectrograph (IRIS). Using IRIS spectra and filtergrams that sample the chromosphere and transition region, we compare the properties and evolution of spicules as observed in a coordinated campaign with Hinode and the Atmospheric Imaging Assembly. Our IRIS observations allow us to follow the thermal evolution of type II spicules and finally confirm that the fading of Ca II H spicules appears to be caused by rapid heating to higher temperatures. The IRIS spicules do not fade but continue evolving, reaching higher and falling back down after 500-800 s. Ca II H type II spicules are thus the initial stages of violent and hotter events that mostly remain invisible in Ca II H filtergrams. These events have very different properties from type I spicules, which show lower velocities and no fading from chromospheric passbands. The IRIS spectra of spicules show the same signature as their proposed disk counterparts,more » reinforcing earlier work. Spectroheliograms from spectral rasters also confirm that quiet-Sun spicules originate in bushes from the magnetic network. Our results suggest that type II spicules are indeed the site of vigorous heating (to at least transition region temperatures) along extensive parts of the upward moving spicular plasma.« less
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an interface region Imaging Spectrograph first view on solar spicules
arXiv: Solar and Stellar Astrophysics, 2014Co-Authors: T M D Pereira, James R. Lemen, Bart De Pontieu, A M Title, P Boerner, Theodore D. Tarbell, M Carlsson, V H Hansteen, N E Hurlburt, J.-p. WülserAbstract:Solar spicules have eluded modelers and observers for decades. Since the discovery of the more energetic type II, spicules have become a heated topic but their contribution to the energy balance of the low solar atmosphere remains unknown. Here we give a first glimpse of what quiet Sun spicules look like when observed with NASA's recently launched Interface Region Imaging Spectrograph (IRIS). Using IRIS spectra and filtergrams that sample the chromosphere and transition region we compare the properties and evolution of spicules as observed in a coordinated campaign with Hinode and the Atmospheric Imaging Assembly. Our IRIS observations allow us to follow the thermal evolution of type II spicules and finally confirm that the fading of Ca II H spicules appears to be caused by rapid heating to higher temperatures. The IRIS spicules do not fade but continue evolving, reaching higher and falling back down after 500-800 s. Ca II H type II spicules are thus the initial stages of violent and hotter events that mostly remain invisible in Ca II H filtergrams. These events have very different properties from type I spicules, which show lower velocities and no fading from chromospheric passbands. The IRIS spectra of spicules show the same signature as their proposed disk counterparts, reinforcing earlier work. Spectroheliograms from spectral rasters also confirm that quiet Sun spicules originate in bushes from the magnetic network. Our results suggest that type II spicules are indeed the site of vigorous heating (to at least transition region temperatures) along extensive parts of the upward moving spicular plasma.
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The interface region Imaging Spectrograph for the IRIS Small Explorer mission
Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray, 2012Co-Authors: J.-p. Wülser, G. D. Kushner, James R. Lemen, Bart De Pontieu, C. Kankelborg, A M Title, Theodore D. Tarbell, Thomas E. Berger, Leon Golub, C. ChouAbstract:The Interface Region Imaging Spectrograph (IRIS) is a NASA SMall EXplorer mission scheduled for launch in January 2013. 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 UV Imaging Spectrograph. IRIS will obtain UV spectra and images with high resolution in space (0.4 arcsec) and time (1s) focused on the chromosphere and transition region of the Sun, a complex interface region between the photosphere and corona. The IRIS instrument uses a Cassegrain telescope to feed a dual Spectrograph and slit-jaw imager that operate in the 133-141 nm and 278-283 nm ranges. This paper describes the instrument with emphasis on the Imaging Spectrograph, and presents an initial performance assessment from ground test results.
P. Plait - One of the best experts on this subject based on the ideXlab platform.
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Performance of the space telescope Imaging Spectrograph
AIP Conference Proceedings, 2008Co-Authors: Charles W. Bowers, Theodore R. Gull, Bruce E Woodgate, R. A. Kimble, Steven B. Kraemer, Mary Elizabeth Kaiser, Don Lindler, Sara R. Heap, Anthony C. Danks, P. PlaitAbstract:The Space Telescope Imaging Spectrograph (STIS) was installed aboard the Hubble Space Telescope (HST) in February, 1997. STIS operates from the ultraviolet to the near infrared (115–1000 nm) in a variety of spectroscopic and Imaging modes. Orbital characterization of STIS performance is currently underway and some of the initial results are presented here.
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Removing the Fringes from Space Telescope Imaging Spectrograph Slitless Spectra
Publications of the Astronomical Society of the Pacific, 2003Co-Authors: Eliot M. Malumuth, Bruce E Woodgate, Charles W. Bowers, R. A. Kimble, P. Plait, Don Lindler, Robert S. Hill, Ted Gull, Morley M. BloukeAbstract:ABSTRACT Using what is known about the physical and chemical structure of the CCD detector on the Space Telescope Imaging Spectrograph (STIS) and over 50 calibration images taken with different wavelength mappings onto the detector, we have devised a model function that allows us to predict the fringing of any spectral image taken with the STIS CCD. This function is especially useful for spectra taken without a slit with the G750L grating. The STIS parallel observing program uses this “slitless spectroscopy” mode extensively. The arbitrary mapping of wavelength versus position that results from each source's chance position in the field renders direct calibration of the fringe amplitudes in this mode impossible. However, we find that correcting observed data using our semiempirical fringing model produces a substantial reduction in the fringe amplitudes. Tests using the flux calibration white dwarf standard G191‐B2B show that we can reduce the fringe amplitude in the 9000–10000 A region from about 20% pea...
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Coronagraphic Imaging with the Hubble Space Telescope and the Space Telescope Imaging Spectrograph
Publications of the Astronomical Society of the Pacific, 2003Co-Authors: Carol A. Grady, Theodore R. Gull, Bruce E Woodgate, Charles W. Bowers, R. A. Kimble, Don Lindler, Sara R. Heap, Eliot M. Malumuth, Charles R. Proffitt, P. PlaitAbstract:ABSTRACT The unfiltered Space Telescope Imaging Spectrograph (STIS) CCD in tandem with focal plane wedges and a Lyot stop provides a simple white‐light coronagraph with a bandpass of 0.2–1.0 μm, which has been used since late 1998 to image nebulosity around stars in the ranges \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $0.34\leq V\leq 14$ \end{document} and \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \use...
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Hubble Space Telescope Space Telescope Imaging Spectrograph Coronagraphic Imaging of the Herbig Ae Star AB Aurigae
The Astrophysical Journal, 1999Co-Authors: Carol A. Grady, Bruce E Woodgate, P. Plait, A. Boggess, Mark Clampin, Frederick C. Bruhweiler, Don Lindler, Paul KalasAbstract:We present the first broadband, coronagraphic Hubble Space Telescope images of the bright, optically visible, isolated Herbig Ae star AB Aurigae. The Space Telescope Imaging Spectrograph (STIS) images reveal extended circumstellar nebulosity (r ≈ 1300 AU) covering the region of the millimeter continuum and CO disk. The structure is observed in the disk on spatial scales down to 01 (14 AU) and exhibits a north-south asymmetry. A comparison of the STIS data with scattering models for flared disks or disks + envelopes suggests that the disk inclination is i ≤ 45° from the plane of the sky.
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Space Telescope Imaging Spectrograph Parallel Observations of the Planetary Nebula M94-20
Publications of the Astronomical Society of the Pacific, 1999Co-Authors: P. Plait, Theodore R. GullAbstract:The planetary nebula M94--20 in the Large Magellanic Cloud was serendipitously observed with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope as part of the Hubble Space Telescope Archival Pure Parallel Program. We present spatially resolved Imaging and spectral data of the nebula and compare them with ground based data, including detection of several emission lines from the nebula and the detection of the central star. We find the total H alpha + [NII] flux = 7.3e-15 erg s^-1 cm^-2 and we estimate the magnitude of the central star to be m_V = 26.0 +/- 0.2. Many other H alpha sources have been found in M31, M33 and NGC 205 as well. We discuss the use of the parallel observations as a versatile tool for planetary nebula surveys and for other fields of astronomical research.
R. A. Kimble - One of the best experts on this subject based on the ideXlab platform.
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Performance of the space telescope Imaging Spectrograph
AIP Conference Proceedings, 2008Co-Authors: Charles W. Bowers, Theodore R. Gull, Bruce E Woodgate, R. A. Kimble, Steven B. Kraemer, Mary Elizabeth Kaiser, Don Lindler, Sara R. Heap, Anthony C. Danks, P. PlaitAbstract:The Space Telescope Imaging Spectrograph (STIS) was installed aboard the Hubble Space Telescope (HST) in February, 1997. STIS operates from the ultraviolet to the near infrared (115–1000 nm) in a variety of spectroscopic and Imaging modes. Orbital characterization of STIS performance is currently underway and some of the initial results are presented here.
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Removing the Fringes from Space Telescope Imaging Spectrograph Slitless Spectra
Publications of the Astronomical Society of the Pacific, 2003Co-Authors: Eliot M. Malumuth, Bruce E Woodgate, Charles W. Bowers, R. A. Kimble, P. Plait, Don Lindler, Robert S. Hill, Ted Gull, Morley M. BloukeAbstract:ABSTRACT Using what is known about the physical and chemical structure of the CCD detector on the Space Telescope Imaging Spectrograph (STIS) and over 50 calibration images taken with different wavelength mappings onto the detector, we have devised a model function that allows us to predict the fringing of any spectral image taken with the STIS CCD. This function is especially useful for spectra taken without a slit with the G750L grating. The STIS parallel observing program uses this “slitless spectroscopy” mode extensively. The arbitrary mapping of wavelength versus position that results from each source's chance position in the field renders direct calibration of the fringe amplitudes in this mode impossible. However, we find that correcting observed data using our semiempirical fringing model produces a substantial reduction in the fringe amplitudes. Tests using the flux calibration white dwarf standard G191‐B2B show that we can reduce the fringe amplitude in the 9000–10000 A region from about 20% pea...
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Coronagraphic Imaging with the Hubble Space Telescope and the Space Telescope Imaging Spectrograph
Publications of the Astronomical Society of the Pacific, 2003Co-Authors: Carol A. Grady, Theodore R. Gull, Bruce E Woodgate, Charles W. Bowers, R. A. Kimble, Don Lindler, Sara R. Heap, Eliot M. Malumuth, Charles R. Proffitt, P. PlaitAbstract:ABSTRACT The unfiltered Space Telescope Imaging Spectrograph (STIS) CCD in tandem with focal plane wedges and a Lyot stop provides a simple white‐light coronagraph with a bandpass of 0.2–1.0 μm, which has been used since late 1998 to image nebulosity around stars in the ranges \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $0.34\leq V\leq 14$ \end{document} and \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \use...
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Radiation damage effects on the CCD detector of the space telescope Imaging Spectrograph
UV Optical and IR Space Telescopes and Instruments, 2000Co-Authors: R. A. Kimble, P. Goudfrooij, Ronald L. GillilandAbstract:The CCD detector in the Space Telescope Imaging Spectrograph (STIS) on board the Hubble Space Telescope is a backside-illuminated, 1024 x 1024 pixel device developed by Scientific Imaging Technologies for the STIS program. It supports a wide-ranging observing program of Imaging and spectroscopy over the 200-1000 nm wavelength range at the high angular resolution of HST. In the three years since launch, radiation damage to the CCD (primarily due to high energy protons encountered in crossings of the South Atlantic Anomaly) has caused a degradation in the charge transfer efficiency (CTE) and an increase in the dark current. The growth in hot pixel count has been readily observable over the entire period since launch; the CTE degradation has become apparent more slowly, as it has evolved with time and as in-flight calibration test methods have improved. We report here on the calibration tests developed to measure the CTE performance in flight, on the results of those tests, on the monitoring of the CCD dark current, and on potential amelioration strategies for minimizing the scientific impact of the decline in STIS CCD performance.
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On-orbit performance of the space telescope Imaging Spectrograph
Space Telescopes and Instruments V, 1998Co-Authors: R. A. Kimble, Theodore R. Gull, Bruce E Woodgate, Charles W. Bowers, Steven B. Kraemer, Mary Elizabeth Kaiser, Sara R. Heap, Anthony C. Danks, Albert Boggess, Richard F. GreenAbstract:The Space Telescope Imaging Spectrograph (STIS) is a second- generation instrument for the Hubble Space Telescope (HST), designed to cover the 115-1000 nm wavelength range in a versatile array of spectroscopic and Imaging modes that take advantage of the angular resolution, unobstructed wavelength coverage, and dark sky offered by the HST. STIS was successfully installed into HST in 1997 February and has since completed a year of orbital checkout, capabilities that it brings to HST, illustrate those capabilities with examples drawn from the first year of STIS observing, and describe at a top level the on-orbit performance of the STIS hardware. We also point the reader to related papers that describe particular aspects of the STIS design, performance, or scientific usage in more detail.
Don Lindler - One of the best experts on this subject based on the ideXlab platform.
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Performance of the space telescope Imaging Spectrograph
AIP Conference Proceedings, 2008Co-Authors: Charles W. Bowers, Theodore R. Gull, Bruce E Woodgate, R. A. Kimble, Steven B. Kraemer, Mary Elizabeth Kaiser, Don Lindler, Sara R. Heap, Anthony C. Danks, P. PlaitAbstract:The Space Telescope Imaging Spectrograph (STIS) was installed aboard the Hubble Space Telescope (HST) in February, 1997. STIS operates from the ultraviolet to the near infrared (115–1000 nm) in a variety of spectroscopic and Imaging modes. Orbital characterization of STIS performance is currently underway and some of the initial results are presented here.
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Removing the Fringes from Space Telescope Imaging Spectrograph Slitless Spectra
Publications of the Astronomical Society of the Pacific, 2003Co-Authors: Eliot M. Malumuth, Bruce E Woodgate, Charles W. Bowers, R. A. Kimble, P. Plait, Don Lindler, Robert S. Hill, Ted Gull, Morley M. BloukeAbstract:ABSTRACT Using what is known about the physical and chemical structure of the CCD detector on the Space Telescope Imaging Spectrograph (STIS) and over 50 calibration images taken with different wavelength mappings onto the detector, we have devised a model function that allows us to predict the fringing of any spectral image taken with the STIS CCD. This function is especially useful for spectra taken without a slit with the G750L grating. The STIS parallel observing program uses this “slitless spectroscopy” mode extensively. The arbitrary mapping of wavelength versus position that results from each source's chance position in the field renders direct calibration of the fringe amplitudes in this mode impossible. However, we find that correcting observed data using our semiempirical fringing model produces a substantial reduction in the fringe amplitudes. Tests using the flux calibration white dwarf standard G191‐B2B show that we can reduce the fringe amplitude in the 9000–10000 A region from about 20% pea...
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Coronagraphic Imaging with the Hubble Space Telescope and the Space Telescope Imaging Spectrograph
Publications of the Astronomical Society of the Pacific, 2003Co-Authors: Carol A. Grady, Theodore R. Gull, Bruce E Woodgate, Charles W. Bowers, R. A. Kimble, Don Lindler, Sara R. Heap, Eliot M. Malumuth, Charles R. Proffitt, P. PlaitAbstract:ABSTRACT The unfiltered Space Telescope Imaging Spectrograph (STIS) CCD in tandem with focal plane wedges and a Lyot stop provides a simple white‐light coronagraph with a bandpass of 0.2–1.0 μm, which has been used since late 1998 to image nebulosity around stars in the ranges \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\encodingdefault{OT2} \normalfont \selectfont} \DeclareTextFontCommand{\textcyr}{\cyr} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} \landscape $0.34\leq V\leq 14$ \end{document} and \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \use...
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Space Telescope Imaging Spectrograph Coronagraphic Observations of β Pictoris
The Astrophysical Journal, 2000Co-Authors: Sara R. Heap, Don Lindler, Thierry Lanz, Robert H. Cornett, Ivan Hubeny, Stephen P. Maran, Bruce E WoodgateAbstract:We present new coronagraphic images of β Pictoris obtained with the Space Telescope Imaging Spectrograph (STIS) in 1997 September. The high-resolution images (01) clearly detect the circumstellar disk as close to the star as 075, corresponding to a projected radius of 15 AU. The images define the warp in the disk with greater precision and at closer radii to β Pic than do previous observations. They show that the warp can be modeled by the projection of two components: the main disk and a fainter component, which is inclined to the main component by 4°-5° and extends only as far as ≈4'' from the star. We interpret the main component as arising primarily in the outer disk and the tilted component as defining the inner region of the disk. The observed properties of the warped inner disk are inconsistent with a driving force from stellar radiation. However, warping induced by the gravitational potential of one or more planets is consistent with the data. Using models of planet-warped disks constructed by Larwood & Papaloizou, we derive possible masses of the perturbing object.
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Hubble Space Telescope Space Telescope Imaging Spectrograph Coronagraphic Imaging of the Herbig Ae Star AB Aurigae
The Astrophysical Journal, 1999Co-Authors: Carol A. Grady, Bruce E Woodgate, P. Plait, A. Boggess, Mark Clampin, Frederick C. Bruhweiler, Don Lindler, Paul KalasAbstract:We present the first broadband, coronagraphic Hubble Space Telescope images of the bright, optically visible, isolated Herbig Ae star AB Aurigae. The Space Telescope Imaging Spectrograph (STIS) images reveal extended circumstellar nebulosity (r ≈ 1300 AU) covering the region of the millimeter continuum and CO disk. The structure is observed in the disk on spatial scales down to 01 (14 AU) and exhibits a north-south asymmetry. A comparison of the STIS data with scattering models for flared disks or disks + envelopes suggests that the disk inclination is i ≤ 45° from the plane of the sky.
