Search Publications
X-Ray Evidence of a Buried Active Galactic Nucleus in UGC 5101
Nakagawa, Takao; Imanishi, Masatoshi; Terashima, Yuichi +1 more
We present X-ray observations of the ultraluminous infrared galaxy, UGC 5101, thought to contain a buried active galactic nucleus (AGN) based on observations in other wave bands. We detected an absorbed hard component at greater than 3 keV, as well as soft emission in the energy range 0.5-2 keV. The soft X-ray component, possibly due to a modestly…
The Canada-UK Deep Submillimeter Survey. VII. Optical and Near-Infrared Identifications for the 14 Hour Field
Clements, D. L.; Dunne, L.; Eales, S. +5 more
We present the multiwavelength identifications for 23 sources in the Canada-UK Deep Submillimeter Survey (CUDSS) 14h field. The identifications have been selected on the basis of radio and near-infrared data, and we argue that, to our observational limits, both are effective at selecting the correct counterparts of the SCUBA sources. We…
X-Ray Spectroscopy of the Low-Mass X-Ray Binaries 2S 0918-549 and 4U 1543-624: Evidence for Neon-rich Degenerate Donors
Chakrabarty, Deepto; Juett, Adrienne M.
We present high-resolution spectroscopy of the neutron star/low-mass X-ray binaries 2S 0918-549 and 4U 1543-624 with the High Energy Transmission Grating Spectrometer on board the Chandra X-Ray Observatory and the Reflection Grating Spectrometer on board XMM-Newton. Previous low-resolution spectra of both sources showed a broad, linelike feature a…
Simultaneous Ultraviolet and X-Ray Spectroscopy of the Seyfert 1 Galaxy NGC 5548. I. Physical Conditions in the Ultraviolet Absorbers
Kaastra, J. S.; Turner, T. J.; Kraemer, S. B. +9 more
We present new UV spectra of the nucleus of the Seyfert 1 galaxy NGC 5548, which we obtained with the Space Telescope Imaging Spectrograph at high spectral resolution, in conjunction with simultaneous Chandra X-Ray Observatory spectra. Taking advantage of the low UV continuum and broad emission-line fluxes, we have determined that the deepest UV a…
Hubble Space Telescope Observations of High-Velocity Lyα and Hα Emission from Supernova Remnant 1987A: The Structure and Development of the Reverse Shock
Filippenko, Alexei V.; Pun, C. S. J.; Garnavich, Peter +18 more
We present two-dimensional line profiles of high-velocity (~+/-12,000 km s-1) Lyα and Hα emission from supernova remnant 1987A obtained with the Space Telescope Imaging Spectrograph between 1997 September and 2001 September (days 3869-5327 after the explosion). This emission comes from hydrogen in the debris that is excited and ionized …
The Ionized Gas and Nuclear Environment in NGC 3783. III. Detection of a Decreasing Radial Velocity in an Intrinsic Ultraviolet Absorber
Kaiser, Mary Elizabeth; Brandt, W. N.; Kaspi, Shai +14 more
We report an intrinsic absorber with decreasing outflow velocity in the Seyfert 1 galaxy NGC 3783. This is the first detection of a change in radial velocity in an outflow associated with a Seyfert galaxy. These results are based on measurements from 18 observations with the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope, o…
Measuring σ8 with Cluster Lensing: Biases from Unrelaxed Clusters
Smith, Graham P.; Smail, Ian; Kneib, Jean-Paul +3 more
We use gravitational lens models and X-ray spectral analysis of 10 X-ray-luminous galaxy clusters at z~=0.2 to study the impact of cluster substructure on attempts to normalize the matter power spectrum. We estimate that unrelaxed clusters are 30% hotter than relaxed clusters, causing σ8 to be overestimated by 20% if the cluster selecti…
The System Parameters of DW Ursae Majoris
Knigge, C.; Dhillon, V. S.; Szkody, P. +8 more
We present new constraints on the system parameters of the SW Sextantis star DW Ursae Majoris, based on ultraviolet (UV) eclipse observations with the Hubble Space Telescope. Our data were obtained during a low state of the system, in which the UV light was dominated by the hot white dwarf (WD) primary. The duration of the WD eclipse allows us to …
Deuterium toward Two Milky Way Disk Stars: Probing Extended Sight Lines with the Far Ultraviolet Spectroscopic Explorer
Hoopes, Charles G.; Sembach, Kenneth R.; Hébrard, Guillaume +2 more
We have carried out an investigation of the abundance of deuterium along two extended sight lines through the interstellar medium (ISM) of the Galactic disk. The data include Far Ultraviolet Spectroscopic Explorer (FUSE) observations of HD 195965 (B1 Ib) and HD 191877 (B0 V), as well as Space Telescope Imaging Spectrograph (STIS) observations of H…
Transit Target Selection Using Reduced Proper Motions
Gould, Andrew; Morgan, Christopher W.
In searches for planetary transits in the field, well over half of the survey stars are typically giants or other stars that are too large to permit straightforward detection of planets. For all-sky searches of bright V<~11 stars, the fraction is ~90%. We show that the great majority of these contaminants can be removed from the sample by analy…