10662(  1) - 04/05/05 12:24  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      10662
                                                       Version: 1
                                                       Check-in Date: 05-Apr-2005
                                                                      16:24:20

1.Proposal Title:
An dust extinction map of M51 from counts of distant galaxies
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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. Benne Willem Holwerda         Kapteyn Astronomical Institute
   CoI: Dr. Ronald J. Allen               Space Telescope Science Institute             N

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6. Abstract

The number of distant galaxies seen in Heritage Project's ACS images of M51 can be
used to probe the extinction in this spiral disk. The ``Synthetic Field Method''
(Gonzalez et al. (1998), Holwerda et al. (2005a)) can be used to calibrate this
number for crowding and confusion effects. The Heritage Project observing strategy
is very suitable for this kind of work. The total extinction of the disk can be
compared to the disk emission, such as SCUBA sub-mm observations and Spitzer maps
and the atomic hydrogen column density (HI). Such comparisons will reveal the role
of dust in spiral disk of M51.
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                                                10662(  1) - 04/05/05 12:24  - [  2]

            Summary Form for Proposal  10662

  Item                         Used in this proposal
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  Proposal Category            AR
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