10669(  1) - 04/05/05 12:28  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      10669
                                                       Version: 1
                                                       Check-in Date: 05-Apr-2005
                                                                      16:28:11

1.Proposal Title:
A Comparative X-ray and Optical Study of M51
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2. Proposal For  3. Cycle  4. Parallel Pointing Tolerance
AR               14        <none>
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5. Investigators
                                                                                     Contact?
    PI: Mr. Roy Erik Kilgard              Smithsonian Institution Astrophysical
                                          Observatory
   CoI: Dr. Andrea H. Prestwich           Smithsonian Institution Astrophysical         N
                                          Observatory
   CoI: Prof. Martin J. Ward              University of Leicester                       N
   CoI: Dr. Timothy R. Roberts            University of Leicester                       N

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6. Abstract

Observations of nearby galaxies with the Chandra X-ray observatory reveal a
multitude of X-ray point sources, largely X-ray binaries and SNR. The X-ray data can
provide crude classifications for these sources, but the only way to unambiguously
classify the source is by observing an optical counterpart. The Hubble Heritage
observations of M51, to be taken before the beginning of Cycle 14, provide the
perfect optical dataset for comparison with existing X-ray data, combining large
field of view, high angular resolution, and long exposure times. The resulting
information on optical counterparts and environments will allow us to test two
important X-ray diagnostics: first, that X-ray color can be used as a crude method
of source classification, and second that the environment of X-ray sources within a
host galaxy can help determine the formation history of the X-ray population.
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                                                10669(  1) - 04/05/05 12:28  - [  2]

            Summary Form for Proposal  10669

  Item                         Used in this proposal
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  Proposal Category            AR
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