Search Publications
Discovery of the Galaxy Proximity Effect and Implications for Measurements of the Ionizing Background Radiation at Low Redshifts
Chen, Hsiao-Wen; Lanzetta, Kenneth M.; Webb, John K. +1 more
We present an analysis of galaxy and quasi-stellar object (QSO) absorption line pairs toward 24 QSOs at redshifts between z~0.2 and 1 in an effort to establish the relationship between galaxies and absorption lines in physical proximity to QSOs. We demonstrate the existence of a galaxy proximity effect, in that galaxies in the vicinities of QSOs d…
Near-Infrared Spectroscopy and Hubble Space Telescope Imaging of a Dusty Starburst Extremely Red Object
Kneib, J. -P.; Smith, Graham P.; Treu, Tommaso +3 more
We present near-infrared spectroscopy and Hubble Space Telescope (HST) imaging of ERO J164023+4644, an Extremely Red Object (ERO) with (R-K)=5.9 at z=1.05 that has been detected by Infrared Space Observatory (ISO) at 15 µm. ERO J164023 resembles a disk galaxy, with an optical/infrared spectral energy distribution that is strongly reddened by…
New Hubble Space Telescope Spectra of QSO PG 1718+4807: No Evidence for Strong Deuterium Absorption
O'Meara, John M.; Burles, Scott; Tytler, David +6 more
The zabs~0.701 absorption system toward QSO PG 1718+4807 is the only example of a QSO absorption system which might have a deuterium/hydrogen ratio approximately 10 times the value found toward other QSOs. We have obtained new Space Telescope Imaging Spectrograph spectra from the Hubble Space Telescope of the Lyα and Lyman limit regions…
Simultaneous Chandra and Hubble Space Telescope Observations of SMC X-1
McCray, R.; Raymond, J. C.; Kallman, T. +3 more
We present first results from simultaneous ultraviolet (Hubble Space Telescope/STIS) and X-ray (Chandra/ACIS) observations of the SMC X-1/SK 160 eclipsing binary system. Observations covering four orbital phases during each of the X-ray high and X-ray low states were taken in 2000 October-November and 2001 April. The ultraviolet P Cygni lines show…
Observations of Lyα Absorption in a Triple Quasar System
Impey, C. D.; Foltz, C. B.; Young, P. A.
We have obtained follow-up observations of the quasar pair LBQS 0107-025A and B and new observations of the nearby quasar LBQS 0107-0232 with the Hubble Space Telescope Faint Object Spectrograph. Extended wavelength coverage of LBQS 0107-025A and B using the G270H grating was also obtained. This triple system is unique in providing sensitivity to …
Ionizing Photons and Extreme-Ultraviolet Excesses in Clusters of Galaxies
Bland-Hawthorn, J.; Maloney, Philip R.
Observations with the Extreme Ultraviolet Explorer satellite are purported to show extreme-ultraviolet (EUV) and soft X-ray excesses in several clusters of galaxies. If interpreted as thermal emission, this would imply the presence of warm (T~106 K) gas in these clusters with a mass comparable to that of gas at coronal temperatures. If …
Far Ultraviolet Spectroscopic Explorer Observations of a Supernova Remnant in the Line of Sight to HD 5980 in the Small Magellanic Cloud
Blair, William P.; Hoopes, Charles G.; Sembach, Kenneth R. +1 more
We report a detection of far-ultraviolet absorption from the supernova remnant SNR 0057-7226 in the Small Magellanic Cloud (SMC). The absorption is seen in the Far Ultraviolet Spectroscopic Explorer (FUSE) spectrum of the luminous blue variable/Wolf-Rayet star HD 5980. Absorption from O VI λ1032 and C III λ977 is seen at a velocity of 300 km s
Stellar Encounters with the β Pictoris Planetesimal System
Kalas, Paul; Deltorn, Jean-Marc; Larwood, John
We use data from the Hipparcos catalog and the Barbier-Brossat & Figon catalog of stellar radial velocities to test the hypothesis that the β Pic planetesimal disk was disrupted by a close stellar encounter. We trace the space motions of 21,497 stars and discover 18 that have passed within 5 pc of β Pic in the past 1 Myr. β Pic's closest encou…
Detection of a Corrugated Velocity Pattern in the Spiral Galaxy NGC 5427
Pérez, Enrique; Alfaro, Emilio J.; González Delgado, Rosa M. +2 more
Here we report the detection, in Hα emission, of a radial corrugation in the velocity field of the spiral galaxy NGC 5427. The central velocity of the Hα line displays coherent, wavy-like variations in the vicinity of the spiral arms. The spectra along three different arm segments show that the maximum amplitude of the sinusoidal line variations a…
The Super-Star Cluster NGC 1569-A Resolved on Subparsec Scales with Hubble Space Telescope Spectroscopy
Ho, Luis C.; Maoz, Dan; Sternberg, Amiel
We present 3000-10000 Å Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph long-slit spectroscopy of the bright super-star cluster A (SSC-A) in the dwarf starburst galaxy NGC 1569. The 0.05" HST angular resolution allows us, for the first time, to probe for spatial variations in the stellar population of an ~106 Msol…