9912(  1) - 04/04/03 10:13  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9912
                                                       Version: 1
                                                       Check-in Date: 04-Apr-2003
                                                                      10:12:47

1.Proposal Title:
Comparing the ACS Ultra Deep Field to Low Redshift Galaxy Observations
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2. Proposal For  3. Cycle
AR               11
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4. Investigators
                                                                                     Contact?
    PI: Michael Blanton                   New York University
   CoI: Prof. David Hogg                  New York University                           N

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5. Abstract

Though the details depend on their favorite galaxy formation theory, astronomers
generally expect high redshift galaxies to be more luminous, smaller, bluer, and
closer to exponential profiles than to de Vaucouleurs profiles, than are low
redshift galaxies. Some of these predictions have been vindicated by observations of
the Hubble Deep Fields and other surveys, such as the predominance of the blue
population at high redshift. However, in order to distinguish between different
galaxy formation theories, all of them require more consistent quantitative
measurements than have yet been performed. In particular they require a consistent
comparison to high quality low redshift surveys. We propose to perform just such a
comparison to optical results from the Sloan Digital Sky Survey. To perform this
test carefully, we will analyze the instrumental effects on the comparison of low
and high redshift objects, including the differences in resolution, signal-to-noise,
rest-frame wavelengths, and background subtraction. By defining consistent measures
of color, size and profile shape which are robust to these effects we will best be
able to constrain galaxy formation theory. We will release to the community the
software we develop and the simulated images we produce.
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                                                9912(  1) - 04/04/03 10:13  - [  2]

            Summary Form for Proposal  9912

  Item                         Used in this proposal
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  Proposal Category            AR
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