Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Table of Contents
· Reads History
·
· Translate This Page
Title:
Hot Subdwarf Star Membership in Visual Binaries
Authors:
Wade, R. A.; Stark, M. A.
Affiliation:
AA(Penn State), AB(Penn State)
Publication:
American Astronomical Society, 198th AAS Meeting, id.49.06; Bulletin of the American Astronomical Society, Vol. 33, p.855
Publication Date:
05/2001
Origin:
AAS
Bibliographic Code:
2001AAS...198.4906W

Abstract

We have inspected more than 1300 regions (6 x 6 arcmin) of the first Digitized Sky Survey, each centered on the position of a hot subdwarf star (sdB or sdO star). Several per cent of these subdwarfs are found, on a statistical basis, to be reasonably convincing candidate members of wide binaries (common--proper--motion pairs of stars), and another several per cent are identified as possible c.p.m. candidates (wider separations, more crowded fields, etc.). In very crowded fields, no identification of pairs was attempted. Confirmation of these candidate binary systems awaits radial velocity and proper motion studies. In most cases, the red magnitude of the hot subdwarf and its proposed fellow traveler are similar, although this is partly a selection effect. We will present what is currently known about these pairs of stars: photographic magnitude differences and colors, distribution of angular separation vs magnitude, 2MASS colors, etc. We will also present validating studies of control fields, to assess whether the fraction of hot subdwarfs that are visual binary candidates is higher than field stars of similar magnitude. This sample of stars cannot be regarded as complete in any rigorous way and is certainly biased by the selection process. We can nevertheless hope to exploit the (to--be--purified) sample to learn much about the luminosities, ages, and original metallicities of the hot subdwarf stars, and possibly their companions can be used as a kinematically unbiased sample of old disk stars. Supported in part by NASA. This work made use of the Digitized Sky Surveys produced at the Space Telescope Science Institute, the 2MASS Second Incremental Data Release, and the U.S. Naval Observatory USNO-A2 catalogue.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
  New!

Find Similar Abstracts:

Use: Authors
Title
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints