10679(  1) - 04/05/05 12:34  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      10679
                                                       Version: 1
                                                       Check-in Date: 05-Apr-2005
                                                                      16:33:57

1.Proposal Title:
The Low Redshift IGM Enrichment History
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2. Proposal For  3. Cycle  4. Parallel Pointing Tolerance
AR               14        <none>
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5. Investigators
                                                                                     Contact?
    PI: Dr. Jason X. Prochaska            University of California - Santa Cruz
   CoI: Dr. Anthony Aguirre               University of California - Santa Cruz         N
   CoI: Dr. Piero Madau                   University of California - Santa Cruz         N

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6. Abstract

We will analyze the IGM enrichment history at z<1.5 by surveying CIV, SiIV, and OVI
absorption in HST/STIS E140M and E230M archival spectra. Current results on low-z
IGM enrichment are based primarily on OVI and CIV surveys from the HST Key Project
FOS data. The archival STIS spectra have >20x higher resolution and correspondingly
>10x higher sensitivity to metal-line absorption. With this program, we will
investigate the mass density of CIV, OVI and SiIV gas and infer the metallicity of
the IGM. In so doing, we will examine the enrichment history over the past 10 Gyr
(which includes the peak in the cosmological star formation history), as well as
provide a zero-point for comparisons against measurements at z>2. We will also study
the intensity and nature of the low-z extragalactic UV background, and measure the
galaxy/absorber cross-correlation function for a subset (~15) of the sightlines.
Altogether, this program will provide key constratins on metal production and
transport processes including galactic winds, pregalactic enrichment, and AGN
outflows.
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                                                10679(  1) - 04/05/05 12:34  - [  2]

            Summary Form for Proposal  10679

  Item                         Used in this proposal
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  Proposal Category            AR
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