9224(  1) - 12/20/00 23:48  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9224
                                                       Version: 1
                                                       Check-in Date: 20-Dec-2000
                                                                      23:40:57

1.Proposal Title:
The Deep Coronagraphic STIS Point Spread Function
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2. Proposal For  3. Cycle
AR               10
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4. Investigators
                                                                                     Contact?
    PI: Bruce Woodgate                    Goddard Space Flight Center
   CoI: Dr. Carol Grady                   Eureka Scientific                             N
   CoI: Dr. Philip Plait                  ACC                                           N
   CoI: Dr. Randy Kimble                  Goddard Space Flight Center                   N
   CoI: Dr. Ted Gull                      Goddard Space Flight Center                   N
   CoI: Dr. Charles Proffitt              Space Telescope Science Institute             N

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5. Abstract

The last 5 years have seen the study of young planetary systems move beyond theory
and into the realm of fore-front observational astronomy. HST imaging campaigns have
been a key component of these multiwavelength studies by capitalizing on the stable
point spread function (PSF) of the telescope and the availability of coronagraphs to
image circumstellar nebulosity within a few arcseconds of the target stars. In cycle
10, the only coronagraph available onboard HST is STIS. This instrument relies on
the use of the unfiltered CCD in tandem with coronagraphic wedges; the resulting
images have large PSF color effects, which can compromise the ability to
successfully separate the residual PSF from circumstellar nebulosity. While this
separation is straightforward for systems with detached nebulosity (e.g. debris
disks) where the star can be approximated by a color-matched main sequence star,
this process is more complicated for actively accreting systems which are either
intrinsically and unpredictably variable in color as well as magnitude, or those
systems which turn out to be close binary systems. For such stars, a library of
stellar PSFs is needed. We propose a calibration study to assemble such a library,
documenting optimal observing and data reduction strategies, and disseminating this
information (via the STIS handbook) so that the full astronomical community can take
advantage of HST's coronagraphic capability.
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                                                9224(  1) - 12/20/00 23:48  - [  2]

            Summary Form for Proposal  9224

  Item                         Used in this proposal
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  Proposal Category            AR
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