5812(  0) - 07/18/95 18:04  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      5812
                                                       Version: **********
                                                       Check-in Date: **********

1.Proposal Title:
Fluctuations in the Extragalactic Background Light
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2. Scientific Category   3. Proposal For  4. Cycle
Galaxies & Clusters         AR               5
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5. Investigators
                                                                                     Contact?
    PI: Alexander Szalay                  Johns Hopkins University
   CoI: Michael Vogeley                   Johns Hopkins University                      N
   CoI: Andrew Connolly                   Johns Hopkins University                      N
   CoI: Thomas Broadhurst                 Johns Hopkins University                      N

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6. Abstract

We propose to apply statistical analyses to archival WFPC2 images in order to obtain
important new constraints on the physical nature and clustering of the extragalactic
background light (EBL). Fluctuations in the EBL contain a wealth of information
about the evolution and clustering of the population of faint galaxies and
cosmology. Deep CCD images obtained by Tyson and others reveal a population of faint
blue objects which may compromise a significant fraction of the EBL, but their
nature is poorly understood. The integrated flux from galaxies to B=27 accounts for
only 1/10 to 1/4 of the upper limits on the optical EBL. Multi-band deep WFPC2
images obtained as part of several programs are of the requisite quality to examine
the properties of the light not assigned with high significance to discrete sources.
At a redshift z~ 0.5, each WFPC2 field yields a 0.5h^-1 Mpc scale glimpse of the
universe. If the EBL is clustered as strongly as the detected faint galaxies, the
fluctuations will be strong enough to be detected; a null result would likewise be a
significant discovery.
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  Observations Description
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  Real Time Justification
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  Calibration Justification
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  Additional Comments
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                                                5812(  0) - 07/18/95 18:04  - [  2]

  Data Distribution

  Media:           8MM
  Blocking Factor: 10
  Ship To:         PI_Address
  Ship Via:        UPS
  Email:                                                              ,
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                                                5812(  0) - 07/18/95 18:04  - [  3]

            Summary Form for Proposal  5812

  Item                         Used in this proposal
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  Proposal Category            AR
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  Scientific Category          Galaxies & Clusters
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