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Observations of Quasar Hosts with Adaptive Optics at Lick Observatory
Graham, James R.; Lacy, Mark; Lloyd, James P. +4 more
We present near-infrared H-band observations of the hosts of three z~1 quasars from the Sloan Digital Sky Survey made with the adaptive optics system at Lick Observatory. We derive a point-spread function (PSF) for each quasar and model the host plus quasar nucleus to obtain magnitudes and approximate scale sizes for the host galaxies. We find our…
Complex Formation History of the Lenticular Galaxies with Stellar Counterrotation: NGC 4138 and NGC 4550
Sil'chenko, O. K.; Afanasiev, V. L.
Two lenticular galaxies with counterrotating stellar components in their disks have been studied with the Multi-Pupil Fiber Spectrograph of the 6 m telescope (at the Special Astrophysical Observatory). In NGC 4138 the nucleus is certainly chemically distinct, with the central concentration of magnesium enhancement marginally exceeding that of iron…
Discovery of a Star Formation Region in Abell 2052
Koekemoer, Anton M.; Baum, Stefi A.; Sparks, William B. +2 more
We report the discovery of an ultraviolet filament detected in a new Space Telescope Imaging Spectrograph (STIS) NUV-MAMA image of the cD galaxy UGC 9799, located in the cooling-flow cluster Abell 2052 and host to the radio source 3C 317. The filament is ~2 kpc in length and is located at a distance of ~4 kpc from the nucleus along a north-south a…
Observations of the Magnetic Cataclysmic Variable VV Puppis with the Far Ultraviolet Spectroscopic Explorer
Gänsicke, B. T.; Szkody, Paula; Hoard, D. W. +5 more
We present the first far-ultraviolet (FUV) observations of the magnetic cataclysmic variable VV Puppis, obtained with the Far Ultraviolet Spectroscopic Explorer satellite. In addition, we have obtained simultaneous ground-based optical photometric observations of VV Pup during part of the FUV observation. The shapes of the FUV and optical light cu…
The Quadruple System µ Orionis: Three-dimensional Orbit and Physical Parameters
Mason, Brian D.; Fekel, Francis C.; McAlister, Harold A. +3 more
The star µ Orionis is a spectroscopic visual quadruple system in which each visual component is a short-period spectroscopic binary. The visual orbit has a period of 18.644 yr, a high eccentricity of 0.7426, and a high inclination of 96.2d. The visual primary consists of an Am star and probably a G or early K dwarf that orbit each other in a…
Optical Identification of the X-Ray Burster X1746-370 in the Globular Cluster NGC 6441
Anderson, Scott F.; Margon, Bruce; Deutsch, Eric W. +2 more
We find convincing observational evidence to confirm the optical identification of the X-ray burster X1746-370, located in the globular cluster NGC 6441. Chandra HRC-I imaging yields a much improved X-ray position for the source, which we show to be fully consistent with our rederived position of a UV-excess star, U1, in the same astrometric refer…
An IUE and HST Archival Study of the Hot White Dwarf in the Symbiotic Variable RW Hydrae
Sion, E. M.; Mikołajewska, J.; Dumm, T. +1 more
We have carried out an ultraviolet spectroscopic study of the hot white dwarf in the eclipsing S-type symbiotic variable RW Hydrae (Porb=370.2 days). Our study used orbital phase-resolved IUE archival low-resolution and high-resolution spectra and Hubble Space Telescope archival spectra, including all available images obtained at inferi…
The Beginning of the End: Hubble Space Telescope Images of Seyfert's Sextet
Charlton, Jane C.; Gallagher, Sarah C.; English, Jayanne +4 more
Hubble Space Telescope (HST) Wide Field Planetary Camera 2 images of Hickson Compact Group (HCG) 79, Seyfert's Sextet, are presented. Both point sources and extended sources detected on the three wide-field chips were photometered in four filters: F336W, F439W, F555W, and F814W. Unlike other HCGs that have been imaged with HST, there do not appear…
On the Absolute Calibration of the Cepheid Distance Scale Using Hipparcos Parallaxes
Di Benedetto, G. P.
The fundamental Hipparcos parallaxes (HIPP) of 219 Cepheids are used for the absolute calibration of the Galactic distance scale sampled by a modern Baade-Wesselink (BW) distance indicator, which reliably accounts for pulsation and thermal properties of Cepheid variable stars. Notably we map thermal properties into the Johnson-Cousins color (V-I).…
Analysis and Models of Photoionized Structures Seen in Hubble Space Telescope Images of NGC 7635
Hester, J. Jeff; Scowen, Paul A.; Moore, Brian D. +1 more
We present the analysis of photoionized structures seen in Hubble Space Telescope Wide Field Planetary Camera 2 images of NGC 7635 and the surrounding H II region S162. We exploit the high spatial resolution images to make a census of the total ionizing flux from the O6.5 IIIf star BD +60°2522. We also construct detailed models of two structures w…