9202(  1) - 12/20/00 23:40  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9202
                                                       Version: 1
                                                       Check-in Date: 20-Dec-2000
                                                                      23:33:40

1.Proposal Title:
An Archive Analysis of a Decade of HST White Dwarf Spectra
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2. Proposal For  3. Cycle
AR               10
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4. Investigators
                                                                                     Contact?
    PI: Jay Holberg                       University of Arizona
   CoI: Dr. Martin Barstow                University of Leicester                       N
   CoI: Dr. Ivan Hubeny                   Goddard Spaceflight Center                    N
   CoI: Dr. Meena Sahu                    Catholic University of America                N

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5. Abstract

We propose to conduct a comprehensive analysis of the existing body of HRS and STIS
spectra of the white dwarf stars. The primary objective of this investigation is to
utilize the high spectral resolution and relatively high S/N of these spectra to
perform detailed analyses of the line shapes of photospheric absorption lines in the
spectra of hot DA white dwarfs. In particular, we are interested in clear evidence
of chemical stratification in the photospheres of these stars, since it now appears
that stratification can explain the occurrence of super-abundances observed in a
number of stars and we now possess the theoretical models to address this
phenomenon. In addition, we will obtain new statistically- based abundance analyses
of a number of hot DO stars using a number of improved models and analysis
techniques.
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                                                9202(  1) - 12/20/00 23:40  - [  2]

            Summary Form for Proposal  9202

  Item                         Used in this proposal
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  Proposal Category            AR
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