Stripped-envelope supernova rates and host-galaxy properties
  The progenitors of stripped-envelope supernovae (SNe Ibc) remain to be
conclsuively identified, but correlations between SN rates and host-galaxy
properties can constrain progenitor models. Here, we present one result from a
re-analysis of the rates from the Lick Observatory Supernova Search. Galaxies
with stellar masses less than $\sim 10^{10}~{\rm M_\odot}$ are less efficient
at producing SNe Ibc than more massive galaxies. Any progenitor scenario must
seek to explain this new observation.
