10663(  1) - 04/05/05 12:25  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      10663
                                                       Version: 1
                                                       Check-in Date: 05-Apr-2005
                                                                      16:24:53

1.Proposal Title:
Tracing the dust extinciton in M101 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. Kip Kuntz                     University of Maryland Baltimore County       N
   CoI: Dr. Ronald J. Allen               Space Telescope Science Institute             N

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6. Abstract

The number of distant galaxies seen in ACS imaging of M101 can be used to probe the
extinction in this spiral galaxy. 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 ACS fields in the archive are a uniquely suitable dataset
for such a project. The total extinction of the disk in relation to the infrared
emission, HI column density and disk light should reveal more on how the dust
component relates to all the other constituents of the spiral disk of M101.
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                                                10663(  1) - 04/05/05 12:25  - [  2]

            Summary Form for Proposal  10663

  Item                         Used in this proposal
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  Proposal Category            AR
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