9201(  1) - 12/20/00 23:40  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9201
                                                       Version: 1
                                                       Check-in Date: 20-Dec-2000
                                                                      23:33:12

1.Proposal Title:
Demography of High Redshift Type Ia Supernovae and Their Progenitor Populations
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2. Proposal For  3. Cycle
AR               10
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4. Investigators
                                                                                     Contact?
    PI: Gerhardt Meurer                   The Johns Hopkins University
   CoI: Dr. Peter Garnavich               University of Notre Dame                      N
   CoI: Prof. Alex Filippenko             University of California                      N
   CoI: Prof. Christopher Stubbs          University of Washington                      N

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5. Abstract

The Hubble diagram of Type Ia supernovae appears to show a significant acceleration
of the cosmic expansion, interpreted as evidence for a new form of dark energy such
as a cosmological constant. However, in order to establish this result securely we
need to show that distance estimates are insensitive to evolving properties of the
progenitor population such as age and metallicity. The best way to test these
possibilities is by demographic studies of supernovae and their progenitor
populations. We propose to study the environments of more than 26 high-redshift
supernovae for which extensive HST WFPC2 data were taken to assemble the Hubble
diagram. We will create deep multicolor images and catalog the properties of the
host, companion and foreground galaxies. We will correlate supernova properties,
such as peak brightness and distance residual, with other quantities known to
correlate with progenitor population age and metallicity, such as the color of the
host galaxy and the distance between the host centroid and the supernova. The
results will either reveal or significantly constrain noncosmological systematics
attached to the use of supernovae as distance indicators at redshifts between 0.3
and 1.
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                                                9201(  1) - 12/20/00 23:40  - [  2]

            Summary Form for Proposal  9201

  Item                         Used in this proposal
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  Proposal Category            AR
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