9206(  1) - 12/20/00 23:42  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9206
                                                       Version: 1
                                                       Check-in Date: 20-Dec-2000
                                                                      23:34:50

1.Proposal Title:
HST + Keck Study of  Disk Systems in Galaxy Cluster Cl0024+16 at Redshift z = 0.39
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2. Proposal For  3. Cycle
AR               10
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4. Investigators
                                                                                     Contact?
    PI: David Koo                         University of California
                                          Observatories/Lick Observatory
   CoI: Ms. Anne Metevier                 University of California, Santa Cruz          N

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5. Abstract

For over twenty years, distant galaxy clusters have been a key arena for galaxy
evolution studies. Despite enormous strides, our understanding of the physical
mechanisms that drive distant cluster evolution remain largely theoretical and
untested. Infall of groups, merging, ``harassment'', quenching of star formation,
starbursts, and ram-pressure stripping all remain viable ideas. Virtually all of
these mechanisms involve disks and gas. Therefore, in contrast to recent studies
that focus on spheroids, we believe a more promising approach to track these
physical processes would be detailed studies of cluster disk systems. This archive
proposal asks support to launch a two-pronged attack to analyze an ideal, rich data
set --- and one that is already in hand. One prong exploits deep B and I HST imaging
of Cl 0024+1654 at z ~ 0.39. The other prong complements the HST data with very high
quality Keck spectra of over 80 sources within the HST WFPC2 field. With both data
sets, we will answer two questions that highlight the physical processes which
affect cluster disk evolution: (1) How do the structures, ages, and age distribution
of S0 disks compare to S0 bulges at z ~ 0.4? (2) How does the Tully-Fisher relation
and M/L of cluster disk systems differ from those in the field, and what properties
of the cluster galaxies correlate with these deviations?
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                                                9206(  1) - 12/20/00 23:42  - [  2]

            Summary Form for Proposal  9206

  Item                         Used in this proposal
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  Proposal Category            AR
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