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Multiwavelength Observations of Hercules X-1/HZ Herculis
Mihara, T.; Kahabka, P.; Charles, P. A. +16 more
We present first results from a multiwavelength campaign to observe the binary pulsar system Her X-1/ HZ Her. The campaign spanned 4 days during 1993 August: observations were taken with five satellites (IUE, EUVE, ROSAT, ASCA, and CGRO/BATSE) and several ground-based facilities. A substantial, unexpected drop in flux at X-ray energies, with no ch…
The Theta -z Relation for HST Bulges and Disks out to Z 0.8
Casertano, Stefano; Glazebrook, Karl; Green, Richard F. +9 more
We present HST scale lengths and ground-based redshifts for 63 faint field galaxies down to I <~ 21.5 mag from the Medium-Deep Survey. These have measured redshifts z <~ 0.8 and half-light radii 0.1" < r_e_, r_s_ < 5". We present the {THETA}-z relation for r^1/4^-bulges and exponential disks separately for world models with q_0_ = 0.0-…
Deep HST Imaging of Distant Weak Radio and Field Galaxies
Dunlop, J. S.; Keel, W. C.; Windhorst, R. A. +4 more
We present deep Hubble Space Telescope (HST) Wide-Field Camera V- and I-band images of three distant weak radio galaxies with z = 0.311-2.390 and seven field galaxies with z = 0.131-0.58. The images were deconvolved with both the Lucy and multiresolution CLEAN methods, which yield a restoring FWHM of <= 0.2", (nearly) preserve photons and signa…
HST Imaging of Quasi-stellar Objects with WFPC2
Holtzman, Jon; Sparks, W. B.; Hutchings, J. B. +3 more
Early images were taken with the optically corrected WFPC2 camera of the Hubble Space Telescope of the low-redshift QSOs 1229+204 and 2141+175, which are radio-quiet and radio-loud, respectively. We discuss image restoration on the data. The objects were chosen on the basis of structure seen with 0.5" resolution with the CFHT high-resolution camer…
X-Ray Emission from a Simulated Cluster of Galaxies
Katz, Neal; Tsai, John C.; Bertschinger, Edmund
Using the 1993 cluster simulation of Katz & White, we analyze the intracluster medium and investigate the accuracy of the standard hydrostatic method for determining cluster masses. We show that the simulated cluster gas is in hydrostatic equilibrium with a subsonic flow toward the center. Inside a radius of ∼100 kpc, this flow is in a steady …
The HST Quasar Absorption Line Key Project. IV. HST Faint Object Spectrograph and Ground-based Observations of the Unusual Low-Redshift Broad Absorption Line Quasi-stellar Object PG 0043+039
Turnshek, David A.; Schneider, Donald P.; Savage, Blair D. +10 more
HST FOS observations have shown that the spectrum of the low-redshift (z_em_ ~ 0.384) QSO PG 0043+039 exhibits weak broad absorption lines (BALs). The BALs were discovered during the course of UV spectrophotometry made for the HST Quasar Absorption Line Key Project. The HST data are analyzed along with ground-based optical and IUE spectrophotometr…
Hubble Space Telescope Observations of the Distant Cluster CL 0016+16: Quantitative Morphology of Confirmed Cluster Members
Koo, David C.; Wirth, Gregory D.; Kron, Richard G.
We present Hubble Space Telescope (HST) images of 24 confirmed members of the distant galaxy cluster Cl 0016+16 at redshift 0.55. The Balmer- strong ("E + A") and emission-line galaxies frequently show unusual visual morphology, implying that galaxian interactions produce "active" galaxies in moderate-redshift clusters. We use an image concentrati…
A Search for the Radio Counterpart to the 1994 March 1 Gamma-Ray Burst
Cline, T.; Frail, D. A.; Kulkarni, S. R. +7 more
We report on the results of a search for the radio counterpart to the bright γ-ray burst of 1994 March 1. Using the Dominion Radio Astrophysical Observatory Synthesis Telescope sensitive, wide-field radio images at 1.4 GHz and 0.4 GHz were made of a region around GRB 940301. A total of 15 separate radio images were obtained at each frequency, samp…
WFPC2 Observations of the Globular Cluster M30
Schneider, Donald P.; Yanny, Brian; Bahcall, John N. +1 more
We describe images of the center of the dense globular cluster M30 (NGC 7099) obtained with the Hubble Space Telescope Wide Field/Planetary Camera 2 (HST WFPC2). Data taken in the F336W, F439W, and F555W filters (approximately U, B, and V) yield a color-magnitude diagram with photometric errors of 1 sigma = 0.05 mag for stars with V less than 17.5…
Evidence for a Disk in the Wind of HD 93521: UV Line Profiles from an Axisymmetric Model
Ignace, R.; Bjorkman, J. E.; Cassinelli, J. P. +1 more
Recently it has been suggested (Massa 1992; Howarth & Reid 1993), from the C IV ultraviolet resonance line profile of HD 93521, that there is a high-speed component in the polar outflow from the star as well as a low-speed component in the equatorial regions. In this paper we present theoretical calculations of the line profiles that would be …