Atomic data needed for far ultraviolet astronomy with HUT and FUSE

AbstractThe instrumental characteristics, observational capabilities and scientific results of the Voyager 1 and 2 ultraviolet spectrometers are reviewed. These instruments provide current and ongoing access to low resolution spectra for a wide variety of astronomical sources in the 500 to 1700 Å band. Observations of the brightest OB stars and hot subluminous stars as faint as V = 15 mag. are possible. In the EUV, at wavelengths shortward of 900 Å, several new sources have been detected and a host of potential sources ruled out. In the Far UV, particularly at wavelengths between 900 and 1200 Å, Voyager is capable of observing a wide range of stellar and non-stellar sources. Such observations can often provide a valuable complement to IUE and other data sets at longer wavelengths. The Voyager spectrometers have proved remarkably stable photon counting instruments, capable of extremely long integration times. The long integration times, relatively large field of view, and location in the outer solar system also provide an ideal platform for observations of sources of faint diffuse emission, such as nebulae and the general sky background.

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Digital micromirror array enabled integral field spectroscopy for far-ultraviolet astronomy

MOEMS and Miniaturized Systems XVII ◽

10.1117/12.2292331 ◽

2018 ◽

Author(s):

Amanda R. Hendrix ◽

Brian T. Fleming ◽

Eric Schindhelm ◽

Rachel M. Tyler ◽

Emily M. Witt ◽

...

Keyword(s):

Ultraviolet Astronomy ◽

Integral Field Spectroscopy ◽

Field Spectroscopy ◽

Far Ultraviolet ◽

Integral Field ◽

Micromirror Array

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High Efficiency Photon Counting Detectors for the FAUST Spacelab Far Ultraviolet Astronomy Payload

IEEE Transactions on Nuclear Science ◽

10.1109/tns.1987.4337298 ◽

1987 ◽

Vol 34 (1) ◽

pp. 41-45 ◽

Cited By ~ 15

Author(s):

O. H. W. Siegmund ◽

M. Lampton ◽

J. Bixler ◽

J. Vallerga ◽

S. Bowyer

Keyword(s):

High Efficiency ◽

Photon Counting ◽

Ultraviolet Astronomy ◽

Photon Counting Detectors ◽

Far Ultraviolet

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Atomic Data Needed for Fuv Astronomy with Hut and Fuse

Highlights of Astronomy ◽

10.1017/s1539299600009783 ◽

1992 ◽

Vol 9 ◽

pp. 571-572

Author(s):

Jeffrey L. Linsky

Keyword(s):

Cross Sections ◽

Molecular Data ◽

Atomic Data ◽

Ultraviolet Spectra ◽

Far Ultraviolet

AbstractThe important atomic and molecular data needed by astrophysicists who analyze far ultraviolet spectra include accurate wavelengths, ocsillator strengths, molecular data for six molecules, and especially electron collisional exciatation cross sections.

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A Discussion on solar studies with special reference to space observations - High resolution interferometric studies of the solar magnesium II doublet spectral region

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1971.0058 ◽

1971 ◽

Vol 270 (1202) ◽

pp. 47-53 ◽

Cited By ~ 9

Keyword(s):

High Resolution ◽

Active Regions ◽

Line Profiles ◽

Broad Absorption ◽

Ultraviolet Astronomy ◽

Extinction Limit ◽

Cosmic Abundance ◽

Emission Core ◽

Far Ultraviolet ◽

Absorption Features

The resonance lines of M gn (A = 279.55 and 280.27 nm) are just beyond the extinction limit of the Earth’s atmosphere. Because of the high cosmic abundance of magnesium, these lines are particularly important in ultraviolet astronomy and with the extension of interference spectroscopy into the far ultraviolet (Bradley 1968), sophisticated optical techniques can now be employed at these wavelengths. On the Sun, the M gn resonance lines consist of a broad absorption with a pronounced emission core similar to the H and K lines of Ca 11, but with more prominent emission and absorption features, so that the Mg 11H and K lines are much more sensitive indicators of chromospheric phenomena. The discovery (Kachalov & Yakovleva, 1962) of structure in the emission core, giving a doubly reversed profile, confirmed the similarity with CAII. The structure of the emission core was well resolved in high resolution {ca. 3 pm) echelle spectrograms obtained with a Sun-pointed rocket (Purcell, Garrett & Tousey 1963). These echelle line profiles were, however, composite ones averaged over one third of the solar disk, so that it was not possible to distinguish between profiles from quiet and active regions, or to determine centre-to-limb variations.

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The FUSE Mission: Atomic Data Needs in the 900–1200 Å Spectral Region

Highlights of Astronomy ◽

10.1017/s1539299600012892 ◽

2002 ◽

Vol 12 ◽

pp. 79-81

Author(s):

Kenneth R. Sembach

Keyword(s):

High Resolution ◽

Solar System ◽

Interstellar Medium ◽

Absorption Line ◽

Ground State ◽

Spectral Region ◽

Theoretical Calculations ◽

Oscillator Strengths ◽

Atomic Data ◽

Far Ultraviolet

AbstractThe Far Ultraviolet Spectroscopic Explorer (FUSE) is presently producing high resolution (R ∼ 20,000) absorption-line spectra of astronomical objects ranging from Solar System planets to quasars. The 900-1200 Å spectral region observed by FUSE is exceedingly rich in atomic and molecular transitions arising out of the ground state. It is already clear from early FUSE observations that the atomic data (e.g., oscillator strengths) for some transitions are considerably different than those predicted by theoretical calculations. I briefly describe the most pressing oscillator strength needs in this wavelength range for studies of the interstellar medium.

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