The host galaxies of core-collapse supernovae and gamma ray bursts
  We present a comparative study of the galactic and small scale environments
of gamma-ray bursts (GRB) and core collapse supernovae (CCSN). We use a sample
of 34 GRB hosts at z<1.2, and a comparison sample of 58 supernova hosts located
within the Great Observatories Origins Deep Survey footprint. We fit template
spectra to the available photometric data, which span the range 0.45-24 micron,
and extract absolute magnitudes, stellar masses and star formation rates from
the resulting fits. Our results broadly corroborate previous findings, but
offer significant enhancements in spectral coverage and a factor 2-3 increase
in sample size. Specifically, we find that CCSN occur frequently in massive
spirals (spiral fraction ~50%). In contrast GRBs occur in small, relatively low
mass galaxies with high specific and surface star formation rates, and have a
spiral fraction of only ~10%. A comparison of the rest frame absolute
magnitudes of the GRB and CCSN sample is less conclusive than found in previous
work, suggesting that while GRB hosts are typically both smaller and bluer than
those of CCSN their total blue light luminosities are only slightly lower. We
suggest this is likely due to rapid periods of intensified star formation
activity, as indicated by the high specific star formation rates, which both
create the GRB progenitors and briefly significantly enhance the host galaxy
blue luminosity. Finally, our analysis of local environments of GRBs and CCSN
shows that GRBs are highly concentrated on their host light, and further occur
in regions of higher absolute surface luminosity than CCSN.
