10299(  1) - 04/02/04 11:22  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      10299
                                                       Version: 1
                                                       Check-in Date: 02-Apr-2004
                                                                      11:21:36

1.Proposal Title:
Morphological analysis of z=5.7 Lyman Alpha sources in the GOODS/UDF fields
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2. Proposal For  3. Cycle  4. Parallel Pointing Tolerance
AR               13        <none>
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5. Investigators
                                                                                     Contact?
    PI: Dr. Norbert Pirzkal               Space Telescope Science Institute
   CoI: Dr. Chun Xu                       Space Telescope Science Institute             N
   CoI: Dr. JunXian wang                  The Johns Hopkins University                  N
   CoI: Dr. Richard Hook                  Space Telescope - European Coordinating       N
                                          Facility
   CoI: Dr. Sangeeta Malhotra             Space Telescope Science Institute             N
   CoI: Dr. James Rhoads                  Space Telescope Science Institute             N

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6. Abstract

We propose to carefully measure the morphology of z=5.7, narrow band selected Lyman
Alpha emitters in the GOODS-S and UDF fields. The candidate objects will be selected
using existing observations of these fields taken from the ground, under sub
arcsecond seeing conditions, and using two narrow band filters (823 nm and 815nm).
While the number of detections of high redshift Lyman Alpha sources has been
steadily increasing in the past year, very little is known about the source of the
Lyman Alpha emission. The observed high Lyman Alpha equivalent widths of these
objects have been explained using a variety of scenarios such as extreme youth of
the stellar population, zero metallicity objects, energetic winds or type II
quasars. Studying the morphology of these objects should provide us with a unique
opportunity to differentiate between several processes believed to be behind the
observed Lyman Alpha emission. Recently, and soon to be made, public HST ACS
observations of the GOODS/UDF fields, with their high angular resolutions and its
well calibrated, stable PSF provide us with a unique opportunity to study the
clumpiness and spatial extension of these objects.
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                                                10299(  1) - 04/02/04 11:22  - [  2]

            Summary Form for Proposal  10299

  Item                         Used in this proposal
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  Proposal Category            AR
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