9193(  1) - 12/20/00 23:37  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9193
                                                       Version: 1
                                                       Check-in Date: 20-Dec-2000
                                                                      23:29:04

1.Proposal Title:
Looking Out From the Galaxy
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2. Proposal For  3. Cycle
AR               10
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4. Investigators
                                                                                     Contact?
    PI: Jane Charlton                     The Pennsylvania State University
   CoI: Dr. Christopher Churchill         The Pennsylvania State University             N
   CoI: Dr. Kenneth Sembach               The Johns Hopkins University                  N

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5. Abstract

We aim to study the distribution many ionization stages of gas by looking out from
the Milky Way galaxy along 33 lines of sight toward various AGNs and QSOs. The HST
archive is rapidly accumulating high resolution UV spectra of these objects with
STIS/E140M and E230M. The majority have been observed to study absorption by
intervening galaxies by the AGN/QSO itself. However, the kinematically complex,
redshift zero absorption features in these spectra can be used to survey the gas in
the disk, halo, and extended group environment of the Milky Way. With the archival
spectra we will conduct a survey for high velocity clouds in the vicinity of the
Milky Way and Local Group, much more sensitive than traditional 21-cm probes. We
will also consider the physical conditions of gas related to the extended corona
surrounding the Milky Way disk, focusing on the kinematic distributions of high
ionization transitions. The local environment, where we can study directly the
structures, star formation rate, and distribution of \HI, is a calibrator for
studies of complex metal--line absorption systems at higher redshifts. Of particular
interest is the evolution of galaxy coronae and the origin of ``satellite'' high
velocity absorption features seen in many strong Mg II absorption line systems, i.e.
their relationship to Galactic high velocity clouds.
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                                                9193(  1) - 12/20/00 23:37  - [  2]

            Summary Form for Proposal  9193

  Item                         Used in this proposal
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  Proposal Category            AR
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