7997(  1) - 04/16/98 14:12  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      7997
                                                       Version: 1
                                                       Check-in Date: 16-Apr-1998
                                                                      14:09:26

1.Proposal Title:
Extending the Interstellar CO/H_2 Correlation Using HST and FUSE Spectra
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2. Proposal For  3. Cycle
AR               7
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4. Investigators
                                                                                     Contact?
    PI: Theodore P. Snow                  University of Colorado
   CoI: Ralph Y. Shuping                  University of Colorado                        N
   CoI: Donald C. Morton                  National Research Council of Canada           N

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5. Abstract

We propose to retrieve and analyze HST/GHRS high-resolution data on interstellar CO
absorption bands in order to extend the known correlation between CO and H_2 beyond
the current limits based on UV absorption measures, and also to enhance the utility
of FUSE data on far-UV CO transitions for which f- values are currently not well
known. The CO band spectra in the HST/GHRS archive will be analyzed to determine CO
column densities for comparison with molecular hydrogen abundances from FUSE, to
extend the known ratio of CO/H_2. The CO results will also be compared with those
from far-UV CO bands observed with FUSE in some of the same stars, to help establish
the correct f-values for the far-UV bands. Our archival search reveals 51 early-type
stars for which GHRS echelle data exist covering one or more CO bands. Of these 51,
12 are on the FUSE PI team list for H_2 observations, and we expect to add others to
the FUSE list in the future, to obtain H_2 measurements to complement the existing
CO data. In addition to extending the known CO/H_2 correlation, we will also extract
^12CO/^13CO ratios for archival stars having sufficient column densities and data
quality to allow the detection and analysis of ^13CO.
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  Data Distribution

  Media:           ELECTRONIC
  Blocking Factor: 10
  Ship To:         PI_Address
  Ship Via:
  Email:
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                                                7997(  1) - 04/16/98 14:12  - [  2]

            Summary Form for Proposal  7997

  Item                         Used in this proposal
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  Proposal Category            AR
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