9197(  1) - 12/20/00 23:38  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9197
                                                       Version: 1
                                                       Check-in Date: 20-Dec-2000
                                                                      23:31:17

1.Proposal Title:
Archival Study of Acoustic Nuclear Spirals in Galaxies
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2. Proposal For  3. Cycle
AR               10
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4. Investigators
                                                                                     Contact?
    PI: Debra Elmegreen                   Vassar College
   CoI: Dr. Bruce Elmegreen               IBM Watson Research Center                    N

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5. Abstract

We plan to examine the dust morphology and model the opacity in the central disk
regions of 100 normal and active galaxies in order to study pressure-driven waves
that are predicted to dominate over density waves in certain cases. Such acoustic
waves may provide a mechanism for the transport of material into active centers of
nonbarred galaxies. Our sample will include Seyfert and normal nonbarred and barred
galaxies so that the results for nonbarred Seyferts can be compared with others of
the same Hubble type. We will measure the dust- interdust contrast and do radiative
transfer models to estimate the dust densities, and we will compare the dust spiral
pitch angles and number of arms versus radius to compare with model predictions.
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                                                9197(  1) - 12/20/00 23:38  - [  2]

            Summary Form for Proposal  9197

  Item                         Used in this proposal
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  Proposal Category            AR
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