8374(  2) - 12/18/98 16:51  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      8374
                                                       Version: 2
                                                       Check-in Date: 18-Dec-1998
                                                                      16:50:20

1.Proposal Title:
The Morphology of Dust Lanes in Barred Spirals
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2. Proposal For  3. Cycle
AR               8
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4. Investigators
                                                                                     Contact?
    PI: Beverly Smith                     University of Colorado

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5. Abstract

We propose to use the HST archives to investigate gas inflow along bars in spiral
galaxies, by studying in detail the structure of the dust lanes along these bars. In
nearby galaxies, these dust lanes are typically about 1'' wide (50 pc at a distance
of 10 Mpc) and so are unresolved or nearly unresolved on groundbased images. With
the unprecedented resolution of HST, however, these features are well-resolved,
providing the opportunity to study their structure in detail. These dust lanes trace
the inflowing gas, which is difficult to detect directly along bars, and so provide
information about clumping, shocks, and cloud formation in the inflowing gas. The
HST archives contain a large number of WFPC2 images of nearby spiral galaxies. With
these data, we will be able to determine if these lanes are continuous or clumpy and
if they are separated into multiple streams. With the large sample of data
available, we will be able to determine if the structure varies from galaxy to
galaxy and if there are trends (i.e., are the lanes clumpier, weaker, and/or wider
in weaker bars? In galaxies without strong circumnuclear star formation?). These
data will provide a valuable test of theoretical models of gas inflow along bars,
addressing questions about the importance of self-gravity, viscosity, and shocks in
driving gas inflow.
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  Data Distribution

  Paper Products:  NO
  Media:           ELECTRONIC
  Blocking Factor: 10
  Ship To:         PI_Address
  Ship Via:
  Email:
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                                                8374(  2) - 12/18/98 16:51  - [  2]

            Summary Form for Proposal  8374

  Item                         Used in this proposal
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  Proposal Category            AR
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