10640(  1) - 04/05/05 12:12  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      10640
                                                       Version: 1
                                                       Check-in Date: 05-Apr-2005
                                                                      16:11:52

1.Proposal Title:
HST Observations of MilliJansky Radio Sources from the VLA FIRST Survey
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2. Proposal For  3. Cycle  4. Parallel Pointing Tolerance
AR               14        <none>
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5. Investigators
                                                                                     Contact?
    PI: Dr. Robert H. Becker              University of California - Davis
   CoI: Dr. Richard L. White              Space Telescope Science Institute             N
   CoI: Dr. Michael D. Gregg              University of California - Davis              N
   CoI: Dr. Willem De Vries               University of California - Davis              N

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6. Abstract

The VLA FIRST survey has imaged 9, 000 square degrees of the North and South
Galactic Caps at 1.4 GHz to a peak flux density limit of 1 mJy with an angular
resolution of 5 arcsec and source positions better than 1 arcsec down to the catalog
detection limit. The source catalog from this area contains about 900, 000 objects.
The median optical brightness of mJy radio galaxies is approximately 23.5. The
number of magnitude 23.5 galaxies per square degree is large (2.5 x 10^4\ deg^-2),
so that positions of <1 arcsec accuracy are required to identify the optical
counterparts with confidence. The FIRST survey is the only wide area radio survey
with positions accurate enough to identify and study the faint optical counterparts
for the majority of the sources. Of course, these galaxies are not only faint; they
are also of small angular size and usually have point-like, active nuclei. Only HST
has the angular resolution required to study the morphology and evolution of these
objects. We propose to study the optical characteristics of a large sample of faint
radio galaxies by analyzing all the publicly available ACS images in the HST Data
Archive that contain cataloged FIRST sources.
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                                                10640(  1) - 04/05/05 12:12  - [  2]

            Summary Form for Proposal  10640

  Item                         Used in this proposal
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  Proposal Category            AR
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