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An Atlas of Ultraviolet Spectra of Star-forming Galaxies
Panagia, N.; Calzetti, D.; Wyse, Rosemary F. G. +2 more
An atlas of ultraviolet spectra of the central regions of 143 spiral, irregular, blue compact, Seyfert 2, and starburst galaxies is produced by combining 387 low-resolution spectra from the IUE data archives. The spectra have been extracted with an optimal algorithm and co-added to produce spectra with the best possible signal-to-noise ratio. Our …
The Hubble Space Telescope Quasar Absorption Line Key Project. I. First Observational Results, Including Lyman-Alpha and Lyman-Limit Systems
Turnshek, David A.; Schneider, Donald P.; Savage, Blair D. +9 more
We present spectra for a total of 37 quasars with small and moderate redshifts; the quasars were observed with the Faint Object Spectrograph of the Hubble Space Telescope. The spectra are obtained either at a resolution of R = 1300 (hereafter "higher resolution") or a resolution of r = 180 (hereafter "lower resolution"). We report new higher resol…
The Hubble Space Telescope Quasar Absorption Line Key Project. II. Data Calibration and Absorption-Line Selection
Turnshek, David A.; Schneider, Donald P.; Savage, Blair D. +10 more
We present the observational and data processing aspects of the Hubble Space Telescope Quasar Absorption Line Key Project. Topics discussed include the observational technique, calibration of the data, software that simulates the data, the automated procedure used to identify and characterize the absorption features, and the determination of the s…
Ultraviolet Spectra of QSOs, BL Lacertae Objects, and Seyfert Galaxies
Turnshek, David A.; Lanzetta, Kenneth M.; Sandoval, Jennifer
Motivated by the possibility of detecting strong absorption features toward extragalactic background objects, we present optimally extracted and co-added IUE spectra of QSOs, BL Lac objects, and Seyfert galaxies. These spectra together with those presented (in a similar work) by Kinney et al. form an essentially complete sample of the SWP, LWP, an…
A Synoptic Study of H alpha Line Profile Variability in the T Tauri Star SU Aurigae
Giampapa, Mark S.; Basri, Gibor S.; Johns, Christopher M. +1 more
We present a catalog of 106 high spectral resolution observations of the H-alpha line profile in the T Tauri star SU Aurigae, obtained during the period from 1986 October through 1990 November. The spectra were acquired during joint synoptic programs to observe selected T Tauri stars using the Hamilton Echelle Spectrometer of the Lick Observatory …
Excitation Rate Coefficients and Line Ratios for the Optical and Ultraviolet Transitions in S II
Cai, Wei; Pradhan, Anil K.
New calculations are reported for electron excitation collision strengths, rate coefficients, transition probabilities, and line ratios for the astrophysically important optical and UV lines in S II. The collision strengths are calculated in the close coupling approximation using the R-matrix method. The present calculations are more extensive tha…
The Structure of the Core of 47 Tucanae from Hubble Space Telescope Observations
Ferraro, Francesco R.; Paresce, Francesco; de Marchi, Guido
A set of moderately deep, high-resolution images of the core of the Galactic globular cluster NGC 104 (47 Tucanae) taken by the Faint Object Camera F/48 relay on the Hubble Space Telescope through the filters F140W, F220W, and F342W are presented and analyzed. The core is completely resolved in these bands for the first time, with approximately 35…
An Improved Ultraviolet Spectral Line List for the Symbiotic Star RR Telescopii
Feibelman, W. A.; Doschek, G. A.
We have remeasured wavelengths and intensities of International Ultraviolet Explorer (IUE) spectra of the symbiotic star, RR Tel. The main work is centered on the long 820 minute exposure high-resolution spectrum obtained on 1983 June 18. The list is intended to serve as a source of improved intensities and wavelengths for the ultraviolet spectrum…
Star Counts from the Hubble Space Telescope Snapshot Survey. I. Galactic Models
Gould, A.; Maoz, D.; Bahcall, J. N.
We report on a photometric study of stars from 450 fields at high Galactic latitudes that were observed in the Hubble Space Telescope Snapshot Survey to an average limiting apparent magnitude of V = 21.4. There are 166 fields that contain quasars selected in radio, X-ray, and color-excess surveys. This sample of 273 stars is free of selection bias…
IUE Short-Wavelength High-Dispersion Line List for the Symbiotic Nova RR Telescopii
Aufdenberg, Jason P.
An 820 minute and other long-exposure archival SWP IUE high-dispersion spectra of symbiotic star RR Tel have been combined to form a composite spectrum. In most of these spectra many lines are saturated, but weaker features appear above the continuum. Their wavelengths were measured from the composite spectrum and compared with the line list from …