Search Publications
Echelle Spectroscopy of Interstellar Absorption toward MU Columbae with the Goddard High Resolution Spectrograph
Savage, B. D.; Sembach, K. R.; Ebbets, D. C. +17 more
Goddard High Resolution Spectrograph echelle-mode observations of the interstellar absorption lines of Mg II, Si IV, C IV, and N V toward mu Columbae (HD 38666) are presented. The observations have a spectral resolution of 3.5 km s^-1 and signal-to-noise ratios (S/Ns) of 20-200. The mu Col sight line (l=237.3d, b=-27.1d, d=0.40 kpc, z=-0.18 kpc) e…
Serendipitous Discovery of a Cataclysmic Variable in the Globular Cluster NGC 6624
Anderson, Scott F.; Margon, Bruce; Deutsch, Eric W. +1 more
Despite indications that classical cataclysmic variable (CV) stars are rare in globular clusters in general, and in the cluster NGC 6624 in particular, we have serendipitously discovered such a star ~6" from the cluster center. A Hubble Space Telescope spectrum of the m~22 object shows strong, broad emission lines typical of numerous field CVs, an…
VLBI Observations of Symmetric Parsec-Scale Twin Jets in the Narrow-Angle-Tail Radio Galaxy NGC 1265 (3C 83.1B)
O'Dea, Christopher P.; Xu, Chun; Biretta, John A.
We present global VLBI observations of the nucleus of the narrow-angle-tail radio galaxy NGC 1265. We report the discovery of symmetric parsec-scale twin jets which are well aligned with the kiloparsec-scale jets. We also present an archival Hubble Space Telescope Wide Field Planetary Camera 2 (WFPC2) image of the galaxy, showing an apparently alm…
A Morphological and Multicolor Survey for Faint QSOS in the Groth-Westphal Strip
Anderson, Scott F.; Beck-Winchatz, Bernhard
Quasars that are representative of the populous faint end of the luminosity function are frustratingly dim, with m~24 at intermediate redshift; moreover, ground-based surveys for such faint QSOs suffer substantial morphological contamination by compact galaxies with similar colors. In order to establish a more reliable ultrafaint QSO sample, we us…
HUBBLE SPACE TELESCOPE View of the Heart of Ursa Minor
Battinelli, Paolo; Demers, Serge
Hubble Space Telescope F606W observations to 26th magnitude are used to investigate the stellar distribution in the center of the Ursa Minor dwarf spheroidal galaxy. The central surface density is found to be low, less than 700 stars arcmin^-2, with no sign of a pronounced cusp. The maximum of the surface density is not found at our adopted center…
Hubble Space Telescope WFPC2 Imaging of Three Low Surface Brightness Dwarf Elliptical Galaxies in the Virgo Cluster
Impey, C. D.; Bothun, G. D.; O'Neil, Karen
Utilizing the F814W and F300W filters, Hubble Space Telescope Wide Field Planetary Camera 2 (WFPC2) images were taken of three low surface brightness dwarf elliptical galaxies in the Virgo Cluster. The intent of the observations was to determine the small-scale structure in these enigmatic galaxies and to attempt to learn something about the natur…
Analyses of the Short-Period Cepheid SU Cassiopeiae
Volk, K.; Milone, E. F.; Wilson, W. J. F.
Baade-Wesselink analyses of this important Galactic classical Cepheid provide new values for the radius, luminosity, distance, and mass and show SU Cas likely to be pulsating in the first overtone. Application of a modified Baade-Wesselink technique and the maximum likelihood method, which we have previously applied to δ Scuti-type variables, yiel…
Far-Ultraviolet Imaging of the Field Star Population in the Large Magellanic Cloud with the Hubble Space Telescope
Brosch, Noah; Zurek, David; MacKenty, John +2 more
We present an analysis of the deepest pure UV observations with the highest angular resolution ever performed, a set of 12 exposures with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 and F160BW filter obtained in parallel observing mode, which covers ~12 arcmin^2 in the Large Magellanic Cloud (LMC), north of the bar, and in the `…
Hubble Space Telescope Imaging Polarimetry of the Gravitational Lens FSC 10214+4724
Hogg, David W.; Eisenhardt, Peter R.; Soifer, B. T. +5 more
We present imaging polarimetry of the extremely luminous, redshift 2.3 IRAS source FSC 10214+4724. The observations were obtained with HST's Faint Object Camera in the F437M filter, which is free of strong emission lines. The 0.7" long arc is unresolved to 0.04" FWHM in the transverse direction and has an integrated polarization of 28%+/-3%, in go…
BOK Globules in the Large Magellanic Cloud
Walsh, J. R.; Chu, Y. -H.; Garnett, D. R. +1 more
We report the discovery of small, isolated dust clouds in the Large Magellanic Cloud (LMC) that are excellent candidates for counterparts to the Bok globules observed in the Galaxy. We detect these small clouds silhouetted against diffuse Hα emission on the basis of parallel imaging with the Wide Field Planetary Camera 2 on the Hubble Space Telesc…