9196(  1) - 12/20/00 23:38  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9196
                                                       Version: 1
                                                       Check-in Date: 20-Dec-2000
                                                                      23:31:00

1.Proposal Title:
Properties of Young Clusters in Spiral Galaxies
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2. Proposal For  3. Cycle
AR               10
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4. Investigators
                                                                                     Contact?
    PI: Andrew Dolphin                    National Optical Astronomy Observatories
   CoI: Dr. Robert Kennicutt Jr.          University of Arizona                         N

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5. Abstract

Young star clusters provide a unique indicator as to the past star formation of a
galaxy. In addition to providing a fossil record of past star formation activity
(similarly to the stellar content), it appears that the amount and nature of cluster
formation depends strongly on the environmental conditions. The nature of these
objects (indistinguishable from bright or foreground stars from the ground) has made
a detailed study difficult in the past; the advent of textitHST and its superior
resolution circumvents this problem. Previous textitHST studies have focused on
interacting systems and merger remnants (where young clusters are expected to be
abundant), leaving a number of questions unanswered, such as: (1) Is the ratio of
massive cluster formation to total star formation constant? (2) Are trends (if any)
along the Hubble sequence analogous to those seen in larger OB associations and HII
regions? We propose to address these and other questions through a survey of t. he.
cluster populations of nearby (< 25 Mpc) galaxies through the use of archival
textitHST images. We have developed an efficient and effective technique for such a
study, with the use of HSTphot for photometry and object size measurements, and
artificial cluster tests to aid in the conversion of observed parameters into
physical parameters.
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                                                9196(  1) - 12/20/00 23:38  - [  2]

            Summary Form for Proposal  9196

  Item                         Used in this proposal
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  Proposal Category            AR
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