8004(  1) - 04/16/98 14:15  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      8004
                                                       Version: 1
                                                       Check-in Date: 16-Apr-1998
                                                                      14:11:52

1.Proposal Title:
The Nova Rate in Galaxies of Different Types from Archival WFPC2 Images
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2. Proposal For  3. Cycle
AR               7
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4. Investigators
                                                                                     Contact?
    PI: Michael Shara                     Space Telescope Science Institute
   CoI: David Zurek                       Space Telescope Science Institute             N
   CoI: Mario Livio                       Space Telescope Science Institute             N

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5. Abstract

It has recently been suggested that the nova rate in galaxies of different types
depends on the galaxy star formation history. Similarly, ground based surveys of a
half dozen relatively nearby galaxies suggest that the nova population of a galaxy
is well represented by two different distributions: the fast, bright ``disk'' novae,
concentrated towards the galactic plane (|z|<100pc) and the slow ``thick-
disk/bulge'' novae, almost two magnitudes fainter than the disk ones, extending up
to |z|<1000pc. We propose to use WFPC2 archival, multi epoch images of ~90 galaxies
to search for erupting novae. The detection of even one or two novae per galaxy per
epoch will allow us to perform a much more definitive test than heretofore possible
on the hypothesis that bulges and disks produce novae at different rates. This will
yield strong constraints on future efforts to model the formation and evolution of
close binary populations in external galaxies.
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  Data Distribution

  Media:           ELECTRONIC
  Blocking Factor: 10
  Ship To:         PI_Address
  Ship Via:
  Email:
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                                                8004(  1) - 04/16/98 14:15  - [  2]

            Summary Form for Proposal  8004

  Item                         Used in this proposal
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  Proposal Category            AR
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