Local Environments of Low-Redshift Supernovae
  We characterize the local (2-kpc sized) environments of Type Ia, II, and Ib/c
supernovae (SNe) that have recently occurred in nearby ($d\lesssim50$ Mpc)
galaxies. Using ultraviolet (UV, from GALEX) and infrared (IR, from WISE) maps
of 359 galaxies and a sample of 472 SNe, we measure the star formation rate
surface density ($\Sigma_{\rm SFR}$) and stellar mass surface density
($\Sigma_\star$) in a 2-kpc beam centered on each SN site. We show that
core-collapse SNe are preferentially located along the resolved galactic
star-forming main sequence, whereas Type Ia SNe are extended to lower values of
$\Sigma_{\rm SFR}$ at fixed $\Sigma_\star$, indicative of locations inside
quiescent galaxies or quiescent regions of galaxies. We also test how well the
radial distribution of each SN type matches the radial distributions of UV and
IR light in each host galaxy. We find that, to first order, the distributions
of all types of SNe mirror that of both near-IR light (3.4 and 4.5 microns,
tracing the stellar mass distribution) and mid-IR light (12 and 22 microns,
tracing emission from hot, small grains), and also resemble our best-estimate
$\Sigma_{\rm SFR}$. All types of SNe appear more radially concentrated than the
UV emission of their host galaxies. In more detail, the distributions of Type
II SNe show small statistical differences from that of near-IR light. We
attribute this overall structural uniformity to the fact that within any
individual galaxy, $\Sigma_{\rm SFR}$ and $\Sigma_\star$ track one another
well, with variations in $\Sigma_{\rm SFR}/\Sigma_\star$ most visible when
comparing between galaxies.
