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The Orbit of the Classical Cepheid V350 SGR
Evans, Nancy Remage; Sugars, Benjamin J. A.
We have obtained velocities for the binary Cepheid V350 Sgr at the David Dunlap Observatory. An orbit has been derived combining these data with velocities from the literature. The spectral type of B9.0 V has been confirmed from an IUE spectrum, leading to a mass of the companion of 2.5 Msun . The uncertainty in the mass is also discussed.
High Dynamic Range VLA Observations of the Gravitationally Lensed Quasar 0957+561
Stocke, John T.; Morse, Jon A.; Harvanek, Michael +1 more
We present 2, 3.6, 6, and 20 cm radio maps of the gravitationally leased quasar 0957+561 obtained with the VLA in A configuration. Besides the well-known jet and lobe structure associated with image A and the point sources associated with image B and the radio source G, the new 3.6 cm maps show interesting extensions of radio source G towards and …
RY Persei: an Early-Type Interacting Close Binary
Olson, Edward C.; Plavec, Mirek J.
We have analyzed photometric and spectroscopic data for the totally-eclipsing binary RY Persei. It is a semidetached binary of the Algol type. However, both the gainer (B4: V) and the loser (F7: II-III) are significantly more massive (6.25 and 1.6 M_sun), hotter, and more luminous (Mbol about -3.3 and -0.2 mag, respectively) than a typi…
The dynamical mass of the beat cepheid Y carinae and stellar opacities.
Bohm-Vitense, E.; Evans, N. R.; Carpenter, K. +3 more
The beat Cepheid, Y Carinae A, has a B9 V companion, Y Car B. The primary period P0 of the Cepheid is 3.64 days and the secondary, P1, is 2.56 days. Its period ratio P1/P0 is thus 0.703. Y Car is the only beat Cepheid known to be a binary and thus offers us the unique opportunity to determine the dynamic…
Ongoing Mass Ejection in the Peculiar, Hot Do Degenerate KPD 0005+5106
Sion, Edward M.; Barstow, Martin A.; Holberg, Jay B. +1 more
We present an analysis of four high-resolution far-ultraviolet spectra of the hot, peculiar DO white dwarf KPD 0005+5106 obtained with short-wavelength prime (SWP) spectrograph aboard the International Ultraviolet Explorer (lUE) spacecraft. These spectra reveal weak, probably variable, peculiar absorption and emission transitions of ultrahigh exci…
An Ultraviolet View of Massive Star Formation in Seyfert Host Galaxies.
O'Connell, Robert W.; Bohlin, Ralph C.; Smith, Andrew M. +5 more
We present deep vacuum ultraviolet (λλ 1200-3300 Å) imagery of four Seyfert galaxies observed by the Ultraviolet Imaging Telescope (UIT): NGC 1068, NGC 2992, NGC 4151, and Mrk 335. These data have a spatial resolution of ∼3" and a limiting surface brightness of ∼24.5 mag arcsec-2 The host galaxies display a diverse range in ultraviolet …
The HST Medium Deep Survey: Light Profiles and Redshifts for Field Galaxies with z<~0.6
Griffiths, R. E.; Windhorst, R. A.; Schmidtke, P. C. +3 more
High-resolution isophotal light profiles have been determined for 36 field galaxies in images taken for the Hubble Space Telescope Medium Deep Survey prior to HST's refurbishment mission. The images were obtained with the Wide Field Camera in "parallel mode" and deconvolved using the Lucy-Richardson image-restoration algorithm with a large library…
Observations of 3C273 with the Goddard High Resolution Spectrograph on the Hubble Space Telescope. II.
Savage, B. D.; Ebbets, D. C.; Crenshaw, D. M. +19 more
Observations of the quasar 3C 273 taken with the Goddard High Resolution Spectrograph in November and December 1993 are presented here. We have included both the fully-reduced spectra, and spectra combined with our earlier (1991) observations. There are a total of 10 new medium resolution exposures covering four wavelength regions: 1164-1201 Angst…
Ultraviolet observations of Chiron with the HST/FOS: Examining a Centaur's Gray Matter
Parker, Joel Wm.; Stern, S. Alan; A'Hearn, Michael F. +2 more
We present ultraviolet (UV) observations of Chiron during two epochs using the Hubble Space Telescope / Faint Object Spectrograph (HST/FOS). The first observations (1996 Jan 23-24 UT) were made 3 weeks before Chiron's perihelion, and include a series of seven spectra obtained over 3.9 hours. A single follow-up observation was made 3 months later (…
Multicolor CCD Photometry of the Poorly Studied Globular Cluster NGC 6541
Alcaino, G.; Liller, W.; Alvarado, F. +3 more
We have carried out the first accurate multicolor (UBVRI) CCD photometry for more than 3000 stars (12m.3<V<21m.0) in the field of the globular cluster NGC 6541. This cluster was neglected in photometric studies after two photographic investigations by Alcaino (1971, A&A;, 13, 399; 1979, A&AS, 35, 233). The color…