Program: GS-2015A-Q-90

We propose GMOS multi-object spectroscopy of a collection of young supernova remnants in M83, identified as part of an extensive campaign including ground-based imaging, deep Chandra and HST/WFC3 observations, and an earlier (2011) GMOS program of spectroscopy. The HST data, obtained after the 2011 program, allow us to select the smallest diameter (hence youngest) SNRs for study. Earlier observations of a few young remnants show a few with evidence of rapid expansion of ejecta, while others have transitioned quickly to the radiative phase. We want to study a more unbiased set of small SNRs to determine how many are in each category and what the driving reasons are. This program will permit a more thorough investigation of the young remnants, permitting shock velocities, electron densities, kinematics, and abundances to be determined. Pre-imaging already exists from our earlier program, and we anticipate four additional masks with GMOS.