Spitzer Space Telescope - General Observer Proposal #3410


Impact of Young Star Clusters in Nearby Galaxies on the Local
Interstellar Medium as a Function of Age Using IRS Spectra

Principal Investigator: Brent Buckalew
           Institution: California Institute of Technology

Co-Investigators: 
Henry Kobulnicky, University of Wyoming                               
Mark Wolfire, University of Maryland                                  

Science Category: nearby galaxies (z<0.05, v_sys<15,000 km/s) 
 Observing Modes: IrsStare 
  Hours Approved: 5.1 

Abstract:
We propose IRS-Stare short-low first order, long-low second order, and
long-low first order spectra of 16 individual young star clusters in 5
nearby galaxies to study the local impact that these clusters have on
their interstellar medium (ISM) in terms of dust/PAH destruction or
creation.  Massive stars in these young (0-10  Myr) star clusters
drive a galaxy's evolution and determine the state of its ISM.  From
the proposed spectra, we will determine:  1) when dust produced by
supernovae is prevalent in a cluster?s evolution, 2) how the dust/PAH
mid- infrared properties evolve over 3-10  Myr, and 3) if hot dust is
responsible for H-K color excesses observed in young star clusters.
Our Spitzer results will aid in the interpretation of dust found in
low-metallicity high-redshift galaxies by providing a timescale for
dust infusion into the ISM and will provide an evolutionary sequence
of young star clusters based on their mid-IR spectra.