8364(  2) - 12/18/98 16:48  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      8364
                                                       Version: 2
                                                       Check-in Date: 18-Dec-1998
                                                                      16:47:03

1.Proposal Title:
Search for Brown Dwarfs around Nearby Stars
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2. Proposal For  3. Cycle
AR               8
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4. Investigators
                                                                                     Contact?
    PI: S. R. Kulkarni                    California Institute of Technology
   CoI: Dr. Ben R. Oppenheimer            California Institute of Technology            N

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5. Abstract

The recent discoveries of substellar objects, including exoplanets and brown dwarfs,
is rapidly revising our earlier pessimistic view of their abundance. The bizarre
spectrum of the cool brown dwarf Gliese 229B, with strong features due to water and
methane, has been the principal guide to the design of searches for more such
objects. However, to date Gliese 229B remains the only cool brown dwarf known. We
propose to use the NICMOS snapshot survey of stars within 10 pc of the sun to
conduct an unbiased search for companions of these stars, based solely on their
proper motions. The principal goal of the NICMOS survey was to find objects similar
to the brown dwarf Gliese 229B by using differential imaging with filters which lie
in and out of characteristic absorption bands. The survey, however, is limited
because it can not establish with certainty that any object fitting the description
above is an actual companion of the star nor could it find companions that are
different from Gliese 229B. We have an extensive database of optical and near
infrared images of the 1'\ fields of view centered on these stars. These images were
taken repeatedly at multiple epochs over the past four years. With this data we can
easily determine whether any of the point sources in the NICMOS images are common
proper motion companions. We will publish all common proper motion companions found.
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  Data Distribution

  Paper Products:  NO
  Media:           ELECTRONIC
  Blocking Factor: 10
  Ship To:         PI_Address
  Ship Via:
  Email:
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                                                8364(  2) - 12/18/98 16:48  - [  2]

            Summary Form for Proposal  8364

  Item                         Used in this proposal
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  Proposal Category            AR
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