9539(  1) - 12/06/01 12:45  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9539
                                                       Version: 1
                                                       Check-in Date: 06-Dec-2001
                                                                      11:49:12

1.Proposal Title:
Dynamical Evolution of the Mass Function of Star Clusters in Different Host Galaxies
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2. Proposal For  3. Cycle
AR               11
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4. Investigators
                                                                                     Contact?
    PI: Michael Fall                      Space Telescope Science Institute

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5. Abstract

We will calculate the evolution of the mass and luminosity functions of star cluster
systems (numbers of clusters per unit mass and luminosity) resulting from the
disruption of clusters by two-body relaxation, gravitational shocks, dynamical
friction, and stellar evolution. In particular, we will determine how the mass and
luminosity functions vary with age, distance from the center of the host galaxy, and
the mass, size, presence or absence of a disk, and other properties of the host
galaxy. Our calculations will be made with extensions of the models recently
developed by Fall & Zhang (2001). The results of these calculations will be compared
with the many mass and luminosity functions of star cluster systems derived from HST
and other observations. This will indicate how much the cluster systems have been
eroded by disruption and how much of the field stellar populations in galaxies is
the debris of disrupted clusters. Another outcome of this investigation will be a
better understanding of when the peak of the luminosity function can or cannot be
used reliably as a standard candle for distance determinations.
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                                                9539(  1) - 12/06/01 12:45  - [  2]

            Summary Form for Proposal  9539

  Item                         Used in this proposal
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  Proposal Category            AR
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