Search Publications
The Nuclear Region of M51 Imaged with the HST Planetary Camera
Lauer, Tod R.; Faber, S. M.; Grillmair, Carl J. +4 more
We present high-resolution, broad- and narrow-band, pre-refurbishment images of the central region of M51 taken with the Planetary Camera of the Hubble Space Telescope. The V-band images show a rather chaotic distribution of dust lanes, though some are oriented radially, roughly aligned with the major axis of the bar, and may be transporting gas t…
Globular Cluster Photometry with the Hubble Space Telescope.VI.WF/PC-I Observations of the Stellar Populations in the Core of M13 (NGC 6205)
Schneider, Donald P.; Yanny, Brian; Bahcall, John N. +2 more
We study the dense core of the globular cluster Messier 13 (NGC 6205) using pre-refurbishment Planetary Camera-I images obtained with the Hubble Space Telescope. Short exposures (60 s) through the F555W and F785LP filters (similar to Johnson V and I, respectively) have been used to obtain V and I photometry of 2877 stars brighter than V ~ 20 in a …
The Axis Ratio Distribution of Local and Distant Galaxies
Windhorst, Rogier A.; Burstein, David; Odewahn, Stephen C.
Surface photometry from 16 HST/WFPC2 fields in the I814-band filter is used to derive the distribution of apparent axis ratios for galaxies in progressively fainter magnitude intervals for I814≤25. We assess the systematic and accidental errors in ellipticity measurements as a function of image resolution and signal-to-noise …
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…