AAS 195th Meeting, January 2000
Session 75. Intrinsic Variable Stars
Display, Friday, January 14, 2000, 9:20am-6:30pm, Grand Hall

[Previous] | [Session 75] | [Next]

[75.16] Duplicity and Variability in HST Guide Stars - An FGS Serendipitius Survey

G. Schneider (Univ. of Az.), J.L. Hershey (CSC), Ed Nelan (STScI)

Subsequent to the publication of our first-epoch catalog (Schneider, et al., 1998, PASP, 110, 1012) we continue the serendipitous search for close double stars (of separations > 20 mas) in the magnitude range 9 to 14.5 using interferometric guiding data from the Hubble Space Telescope Fine Guidance Sensors. In this follow-on phase of our investigation we are more than doubling our initial sample size and temporal baseline of 13,979 acquisitions on 4882 stars observed over 22 months, and with the inclusion of additional FGS1R data improve the sensitivity limits and detection thresholds of the overall sample. In addition, we are now conducting a differential photometric variability study for all observed HST guide stars with sampling rates to 40 Hz and milli-magnitude photometric precision. Here we describe the photometric program in detail, and provide an in-progress summary of the astrometric survey. Support for this work was provided by NASA through grant AR8370 from STScI, which is operated by AURA, Inc. under NASA contract NAS5-26555.

If you would like more information about this abstract, please follow the link to http://nicmosis.as.arizona.edu:8000/pub/gsdoubles.html. This link was provided by the author. When you follow it, you will leave the Web site for this meeting; to return, you should use the Back comand on your browser.

The author(s) of this abstract have provided an email address for comments about the abstract: gschneider@as.arizona.edu

[Previous] | [Session 75] | [Next]