10947(  1) - 04/03/06 11:04  - [  1]

                  HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 10947

Version: 1    Check-in Time: 03-Apr-2006 15:04:33

Title
Galaxy Environments and Evolution in the GOODS-N Field
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Type             Cycle     Parallel Pointing Tolerance
AR               15        <none>
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Investigators
                                                                                     Contact?
    PI: Prof. Marc Davis                  University of California - Berkeley
   CoI: Mr. Michael Cooper                University of California - Berkeley           N
   CoI: Dr. Jeffrey Allen Newman          Lawrence Berkeley National Laboratory         Y
   CoI: Dr. David C. Koo                  University of California - Santa Cruz         N
   CoI: Dr. Kirpal Nandra                 Imperial College of Science                   N
   CoI: Dr. Vicki L. Sarajedini           University of Florida                         N
   CoI: Dr. Darren Croton                 Max-Planck-Institut fur Astrophysik           N
   CoI: Dr. Benjamin Weiner               University of Maryland                        N
   CoI: Mr. Brian Gerke                   University of California - Berkeley           N

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Abstract

In the spirit of a Legacy archival program, we propose to develop a publicly-
available, non-proprietary tool allowing the measurement of the local density of
galaxies (i.e., the "environment") for any object in the GOODS-N field with
0.2<z<1.4, provided only RA, dec, and redshift. Recent studies have shown that the
properties and formation histories of galaxies depend strongly on the environment in
which they are located. By adding environment information to the uniquely deep
multiwavelength dataset available in the GOODS-N field, it will be possible to
uncover many new pieces of the galaxy evolution puzzle. Measuring environments over
the entire GOODS-N field will require a small amount of additional Keck/DEIMOS
spectroscopy surrounding the field; we will make all Keck data and redshifts public
as soon as they are reduced. We can use the resulting 3d environment measurements to
calibrate the use of neighbor counts from the deep GOODS-N (original + SN search)
imaging as a second measure of environment. We will use the environment tool
ourselves for two projects that utilize the nearly-unique GOODS-N HST/ACS and
Chandra/ACIS data: (1) studying the morphology-density relation at z=0.5-1 down to
faint luminosities; and (2) determining the typical environments of low-level AGN
and testing for relationships with host galaxy properties.
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