11238(  1) - 03/30/07 10:59  - [  1]

                  HUBBLE SPACE TELESCOPE OBSERVING PROGRAM 11238

Version: 1    Check-in Time: 30-Mar-2007 14:59:31       STScI Edit Number: 0

Title
Searching For Unresolved Binary Brown Dwarfs Using Point Spread Functions
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Type             Cycle     Parallel Pointing Tolerance
AR               16        <none>
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Investigators
                                                                                     Contact?
    PI: Mr. Jacob J. Albretsen            Brigham Young University
   CoI: Dr. Denise C. Stephens            Brigham Young University                      N
   CoI: Dr. Keith S. Noll                 Space Telescope Science Institute             N

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Abstract

There currently are objects of L and T spectral type with errors in their
classification of +/- 1 to 2. Metallicity and gravitational differences have
accounted for some of these discrepancies, and recent studies have shown unresolved
binary brown dwarfs may offer some explanation as well. However limitations in
technology and resources make it difficult to clearly resolve an object that may be
binary in nature. It has been shown that using model point-spread functions for
single and binary sources have been able to identify statistically strong binary
candidates from images that are apparently unresolved. The HST archive contains
numerous observations of brown dwarfs from NICMOS that have never been rigorously
analyzed for binary properties. Results from for this archive proposal will help
determine if there really is an increase in binary brown dwarfs in the L/T
transition and identify potential candidates for future observations to determine
orbital information.
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