9934(  1) - 04/04/03 10:23  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      9934
                                                       Version: 1
                                                       Check-in Date: 04-Apr-2003
                                                                      10:23:00

1.Proposal Title:
A Multi-Wavelength Study of Super Star Clusters as They Emerge From Their Birth
Material
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2. Proposal For  3. Cycle
AR               11
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4. Investigators
                                                                                     Contact?
    PI: Kelsey Johnson                    University of Wisconsin - Madison

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5. Abstract

We will use multi-wavelength observations available in the HST archive to study the
properties of ultra-young ``super star clusters'' as they emerge from their natal
cocoons to become visible in optical light. These ultra-young (< 1 Myr) clusters
have been recently discovered using radio and mid-IR observations, and they
represent the youngest class of massive star clusters yet observed. However, the
transition between the deeply embedded clusters to the optically visible clusters
has not yet been studied. We have identified five starburst systems from our radio
survey that are known to host ultra- young massive star clusters and have
corresponding multi- wavelength data available in the HST archive spanning the
optical and infrared regimes. In addition, several of these galaxies have narrow-
band observations available, including H- alpha and Pa-alpha. By analyzing these
data in concert with our radio data, we will be able to address the evolutionary
stage at which SSCs become visible in the optical and/or near- IR regimes, whether
there is any correlation between properties determined from radio observations (such
as electron density) and optical characteristics (such as extinction), and what
fraction of recent star formation in these galaxies is optically obscured. These
results will ultimately provide insight on the timescales involved in the earliest
stages of SSC evolution and the properties of massive star formation throughout the
universe. This proposal is complementary to the GO proposal entitled ``NICMOS Survey
of Pre-Natal Super Star Clusters in Starbursts'' submitted by Johnson & Gallagher in
this HST cycle.
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                                                9934(  1) - 04/04/03 10:23  - [  2]

            Summary Form for Proposal  9934

  Item                         Used in this proposal
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  Proposal Category            AR
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