Page 1 PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS ST ScI Use Only ID 3004c Report Date: 09-May-96:17:48 Version: ********** Check-in Date: ********** 1.Proposal Title: DUPLICITY AMONG HYADES STARS-PRELUDE ------------------------------------------------------------------------------------ 2. Scientific Category 3. Proposal For 4. Proposal Type 5. Continuation ID SAT/AST Sub Category ------------------------------------------------------------------------------------ 6. Principal Investigator Institution Country Telephone William H. Jefferys TEXAS, UNIVERSITY OF USA 512-471-4461 PROFESSOR OF ASTRONO ------------------------------------------------------------------------------------ 7. Abstract We propose to use FGS in TRANSFER mode to examine, at high angular resolution, a representative sample of bright probable Hyades cluster members in an effort to establish the incidence of duplicity among Hyades stars. The frequency of multiple stars in stellar systems and populations represents a significant aspect of star formation and stellar evolution. Among Hyades stars brighter than V ~ 5.0, companions should be observable to Delta m ~ 2. Binaries of small Delta m should be readily detectable at V ~ 10. ------------------------------------------------------------------------------------ 8. Scientific Key Words: DUPLICITY; BINARIES; MULTIPLE STARS; HYADES ------------------------------------------------------------------------------------ 9. Est obs time (hours) pri: 20.00 par: 0 10. Num targs pri: 40 par: 0 ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------ Page 2 I. GENERAL FORM Proposal 3004c PI: William H. Jefferys Proposal Title: DUPLICITY AMONG HYADES STARS-PRELUDE ------------------------------------------------------------------------------------ 1. Proposers: Proposers Institution Country ESA ------------------------------------------------------------------------------------ William H. Jefferys TEXAS, UNIVERSITY OF USA Otto G. Franz LOWELL OBSERVATORY USA ------------------------------------------------------------------------------------ 3. Description of proposed observations. Line 1, page 11 defines, for each target, an observation consisting of a set of continuous scans at a scan rate of 0.06 arcsec per sec and a scan length of 1.2 arcsec per interferometer axis. There are 10 scans/observation (total exposure time 200 seconds), sufficient to permit detection of close companions to a Delta- m ~ 2 mag for stars of V ------------------------------------------------------------------------------------------------------------------------------------ Scientific Sub-category ------------------------------------------------------------------------------------------------------------------------------------ Special Requirements CYCLE 0 / 3-29; GUIDE TOL 0.020" / 3-29 ------------------------------------------------------------------------------------------------------------------------------------ Spectral Elements # F5ND F583W ------------------------------------------------------------------------------------------------------------------------------------ Target Names H89 H101 H105 H115 H198 H230 H246 H271 H290 H292 H307 H308 H312 H316 H379 H382 HYADES388 H388 HYADES411 H411 H417 H420 H429 H472 H478 H491 H507 H544 H554 H578 H598 ------------------------------------------------------------------------------------------------------------------------------------