9911(  1) - 04/04/03 10:12  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9911
                                                       Version: 1
                                                       Check-in Date: 04-Apr-2003
                                                                      10:12:24

1.Proposal Title:
Archival Studies of Main Sequence Binaries in 47 Tucanae (NGC104)
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2. Proposal For  3. Cycle
AR               11
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4. Investigators
                                                                                     Contact?
    PI: Charles Bailyn                    Yale University
   CoI: Bing Zhao                         Yale University                               N

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5. Abstract

We plan to analyze 636 F555W and 653 F814W images of 47 Tuc taken during observation
run GO-8267. We will construct an accurate main sequence CMD using all the data in
an optimal way. By analyzing the results with extensive artificial star tests, we
will: (1) calculate the binary frequency in the cluster, (2) calibrate the binary
period distribution by comparing with the known population of short-period eclipsing
binaries, (3) determine the unevolved single-star main sequence luminosity function,
and (4) identify the BY Dra candidates classified by X-ray spectra and temporal
characteristics (X-ray and/or optical) . The results are essential in the studies of
stellar dynamics, stellar population, and origins of dynamically interesting
objects. We have developed robust data reduction techniques and applied them
successfully in similar HST/WFPC2 studies. If this proposal is accepted, the results
obtained will form a major component of graduate student Bing Zhao's Ph.D. thesis.
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                                                9911(  1) - 04/04/03 10:12  - [  2]

            Summary Form for Proposal  9911

  Item                         Used in this proposal
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  Proposal Category            AR
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