Search Publications
A Reanalysis of the Carbon Abundance in the Translucent Cloud Toward HD 24534
Sofia, Ulysses J.; Fitzpatrick, Edward L.; Meyer, David M.
We have reanalyzed the Goddard High Resolution Spectrograph data set presented by Snow et al., which contains the interstellar intersystem C II] λ2325 line through the translucent cloud toward HD 24534 (X Persei). In contrast to the results of Snow et al., we clearly detect the C II] feature at the 3 σ confidence level and measure a C+ …
A Multiwavelength Campaign on γ Cassiopeiae. II. The Case for Corotating, Circumstellar Clouds
Smith, Myron A.; Robinson, Richard D.; Hatzes, Artie P.
Simultaneous X-ray/UV observations over a full day on 1996 March 14-15 have been made of the prototypical B0.5e star γ Cas using the Rossi X-Ray Timing Explorer satellite and the Goddard High Resolution Spectrograph (GHRS) on board the Hubble Space Telescope. The GHRS spectra, taken in the region of the Si IV λλ1394-1403 doublet, also permitted th…
First Results from the Space Telescope Imaging Spectrograph: Optical Spectra of Gliese 229B
Moos, H. W.; Bruhweiler, F. C.; Maran, S. P. +12 more
We report the first Hubble Space Telescope Space Telescope Imaging Spectrograph (STIS) CCD spectroscopy of the bona fide brown dwarf Gliese 229B. The optical spectrum shows absorptions of Cs I at 8944 Å and water vapor bands at 9300-9600 Å. Strong CaH, FeH, TiO, and VO bands observed in late M dwarfs are absent from the spectrum of Gliese 229B. Th…
Lyα Absorption Systems and the Nearby Galaxy Distribution
Grogin, Norman A.; Geller, Margaret J.
We study the galaxy number density (smoothed on a 5 h-1 Mpc scale) around 18 low-redshift Lyα absorbers previously observed with HST. The absorbers lie in the foregrounds of Mrk 335, Mrk 421, Mrk 501, I Zw 1, and 3C 273, all within regions where there are now complete redshift surveys to mZw = 15.5. We construct a smoothed ga…
Hubble Space Telescope Observations of the Gravitationally Lensed Cloverleaf Broad Absorption Line QSO H1413+1143: Spectroscopy of the Lyα Forest and Metal-Line Systems
Turnshek, David A.; Monier, Eric M.; Lupie, Olivia L.
The intervening Lyα forest and metal-line absorbers toward the ``Cloverleaf'' gravitational lens H1413+1143 (zem = 2.54, mv ~ 17) are examined along the four individual sight lines using HST-FOS spectra. The observations probe the Lyα forest systems on size scales of up to 4 h-1 kpc (H0 = 100 h km s…
New Hubble Space Telescope Observations of High-Velocity Lyα and Hα in SNR 1987A
Filippenko, Alexei V.; Pun, C. S. J.; Garnavich, Peter +12 more
We describe and model high-velocity (~15,000 km s-1) Lyα and Hα emission from the supernova remnant SNR 1987A seen in 1997 September and October with the Space Telescope Imaging Spectrograph. Part of this emission comes from a reverse shock located at ~75% of the radius of the inner boundary of the inner circumstellar ring and confined …
NGC 2264 IRS: Evidence for Triggered Star Formation
Schneider, Glenn; Thompson, Rodger I.; Corbin, Michael R. +1 more
As part of its commissioning process the Near-Infrared Camera and Multiobject Spectrometer (NICMOS) obtained images of the infrared source NGC 2264 IRS, also known as Allen's source, in three colors . In addition to the completely overexposed image of IRS there are six point objects, never previously observed, at projected separations of 2.6" to 4…
Cloning Hubble Deep Fields. II. Models for Evolution by Bright Galaxy Image Transformation
Broadhurst, Tom; Bouwens, Rychard; Silk, Joseph
In a companion paper, we outlined a methodology for generating parameter-free, model-independent ``no-evolution'' fields of faint galaxy images, demonstrating the need for significant evolution in the Hubble Deep Field (HDF) at faint magnitudes. Here we incorporate evolution into our procedure, by transforming the input bright galaxy images with r…
The Physical Characteristics of the Small-Scale Interstellar Structure toward µ Crucis
Meyer, David M.; Blades, J. C.; Lauroesch, J. T. +1 more
We present Hubble Space Telescope Goddard High Resolution Spectrograph echelle observations of multiple interstellar lines of C I, Mg I, Cr II, and Zn II toward both stars in the µ Crucis binary system. Despite large differences in the profiles of the neutral species, no significant variations between the stars are seen in the Cr II and Zn I…
Ultraviolet Spectroscopy of the Quasar Pair LB 9605, LB 9612 with the Hubble Space Telescope: Evolution in the Size of the Lyα Absorbers?
Weymann, Ray J.; Foltz, Craig B.; Impey, Chris D. +1 more
Ultraviolet spectroscopy has been obtained with the faint object spectrograph of the Hubble Space Telescope in the Lyα forest of the quasar pair, LB 9605 (zem = 1.834) and LB 9612 (zem = 1.898), in order to measure the size of the Lyα absorbers. The quasars are separated by 1.65 arcmin on the sky corresponding to a proper sep…