An Expanded HST/WFC3 Survey of M83: Project Overview and Targeted
  Supernova Remnant Search
  We present an optical/NIR imaging survey of the face-on spiral galaxy M83,
using data from the Hubble Space Telescope Wide Field Camera 3 (WFC3). Seven
fields are used to cover a large fraction of the inner disk, with observations
in nine broadband and narrowband filters. In conjunction with a deep Chandra
survey and other new radio and optical ground-based work, these data enable a
broad range of science projects to be pursued. We provide an overview of the
WFC3 data and processing and then delve into one topic, the population of young
supernova remnants. We used a search method targeted toward soft X-ray sources
to identify 26 new supernova remnants. Many compact emission nebulae detected
in [Fe II] 1.644 micron align with known remnants and this diagnostic has also
been used to identify many new remnants, some of which are hard to find with
optical images. We include 37 previously identified supernova remnants that the
data reveal to be <0.5'' in angular size and thus are difficult to characterize
from ground-based data. The emission line ratios seen in most of these objects
are consistent with shocks in dense interstellar material rather than showing
evidence of ejecta. We suggest that the overall high elemental abundances in
combination with high interstellar medium pressures in M83 are responsible for
this result. Future papers will expand on different aspects of the these data
including a more comprehensive analysis of the overall supernova remnant
population.
