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Small-Scale Systems of Galaxies. III. X-Ray-detected Elliptical+Spiral Galaxy Pairs in Low-Density Environments
Held, E. V.; Rizzi, L.; Trinchieri, G. +4 more
We present a comprehensive study of the local environments of four elliptical+spiral (E+S) galaxy pairs with the main goal of investigating their formation/evolution histories. We obtained new XMM-Newton data for two pairs (RR 143 and RR 242) that complement existing ROSAT data for the other two (RR 210 and RR 216). The new observations reveal dif…
Washington Photometry of the Red Giant Branch in NGC 6388
Wallerstein, George; Covarrubias, Ricardo; Hughes, Joanne +1 more
We present Washington photometry of the giant branches of the relatively metal-rich globular cluster NGC 6388 and compare it with 47 Tuc. By examining the spatial distribution of stellar colors across the red giant branch and using spectroscopic data on several bright giants, we found that NGC 6388's center is affected by differential reddening of…
Hubble Space Telescope Ultraviolet Spectroscopy of 14 Low-Redshift Quasars
Kaiser, Mary Elizabeth; Laor, Ari; Hall, Patrick B. +35 more
We present low-resolution ultraviolet spectra of 14 low-redshift (zem<~0.8) quasars observed with the Hubble Space Telescope STIS as part of a Snapshot project to understand the relationship between quasar outflows and luminosity. By design, all observations cover the C IV emission line. Ten of the quasars are from the Hamburg-ESO ca…
Properties of the ζ Aur-Type Binary System 22 Vul = QS Vul
Eaton, Joel A.; Shaw, Felecia G.
The 22 Vul system is important for studying the winds and chromospheres of cool evolved stars because the G4 I component is rotating rapidly and probably faster than synchronously. We discuss the system's physical properties in the context of a wide range of constraints on them and propose values that may be marginally better than previous ones (s…
New Ultraviolet Observations of AM CVn
Eracleous, Michael; Wade, Richard A.; Flohic, Hélène M. L. G.
We have obtained observations of the ultraviolet spectrum of AM CVn, an ultrashort-period helium cataclysmic variable, using the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope (HST). We obtained data in time-tag mode during two consecutive orbits of HST, covering 1600-3150 and 1140-1710 Å, respectively. The mean spectrum is…
Multimode Pulsations of the λ Bootis Star 29 Cygni: The 1995 and 1996 Multisite Campaigns
Handler, G.; Krisciunas, K.; Paunzen, E. +19 more
In this paper we present the results of multisite photometric and spectroscopic campaigns, carried out during the years 1995 and 1996, to study the pulsations of a typical λ Bootis star, 29 Cyg. During the 1995 campaign we found well-defined multiperiodicity in 29 Cyg, which was studied in detail during a multilongitude campaign covering a 65 day …
Resolving LB 11146 with Hubble Space Telescope's Fine Guidance Sensor
Nelan, Edmund P.
On the basis of its observed spectra, LB 11146 was identified as a binary system composed of pair of massive (~0.9 Modot) white dwarf stars. However, observations with the Hubble Space Telescope (HST) Faint Object Camera did not resolve the system, and searches for radial velocity variations yielded null results. Subsequent observations…
Automated Selection and Characterization of Emission-Line Sources in Advanced Camera for Surveys Wide Field Camera Grism Data
Ford, H. C.; Meurer, Gerhardt R.; Capak, P. +10 more
We present complementary techniques to find emission-line targets and measure their properties in a semi-automated fashion from grism observations obtained with the Advanced Camera for Surveys aboard the Hubble Space Telescope (HST). The first technique is to find all likely sources in a direct image, extract their spectra, and search them for emi…
Astrometric-Spectroscopic Determination of the Absolute Masses of the HgMn Binary Star φ Herculis
Torres, Guillermo
The mercury-manganese star φ Her is a well-known spectroscopic binary that has been the subject of a recent study by Zavala and coworkers in which they resolved the companion using long-baseline interferometry. The total mass of the binary is now fairly well established, but the combination of spectroscopy with astrometry has not resulted in indiv…
FUSE Observations of the Dwarf Novae UU Aql, BV Cen, and CH UMa in Quiescence
Szkody, Paula; Sion, Edward M.; Godon, Patrick +1 more
We report on FUSE spectra of three U Gem-type, long-period dwarf novae, UU Aql, BV Cen, and CH UMa, taken during their quiescence intervals. We discuss the line identifications in their spectra and attempt to characterize the source(s) of their FUV flux distribution. Archival IUE spectra of CH UMa and BV Cen in quiescence were identified as having…