9530(  1) - 12/06/01 12:41  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9530
                                                       Version: 1
                                                       Check-in Date: 06-Dec-2001
                                                                      11:46:21

1.Proposal Title:
Three-Dimensional Structure of Dust in Galaxy Nuclei
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2. Proposal For  3. Cycle
AR               11
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4. Investigators
                                                                                     Contact?
    PI: William Keel                      University of Alabama

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5. Abstract

HST imagery has demonstrated that dust features are ubiquitous in galactic nuclei.
The occurrence of such features has been linked to recent interactions or dynamical
processes trapping the ISM in small areas against the shearing which would normally
disrupt discrete such structures. In addition, many of the structures seem to be
either very thick or located well above the disk plane in spirals. This proposal
would support a systematic examination of the rich archival data on this question,
specifically aimed at reconstruction of the three- dimensional dust structure within
the nuclei. These results will allow a more complete assessment of the typical dust
masses and structural scales in nuclei, which together with the galaxy dynamics,
will give survival timescales for the features and imply energetics needed to
maintain the observed frequency of these structures. Nonplanar dust structures will
be examined particularly in a set of disturbed and merging galaxies, where they may
play a significant radiative-transfer role.
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                                                9530(  1) - 12/06/01 12:41  - [  2]

            Summary Form for Proposal  9530

  Item                         Used in this proposal
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  Proposal Category            AR
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