Patrick L. Kelly, Robert P. Kirshner
We have used images and spectra of the Sloan Digital Sky Survey to examine
the host galaxies of 519 nearby supernovae. The colors at the sites of the
explosions, as well as chemical abundances, and specific star formation rates
of the host galaxies provide circumstantial evidence on the origin of each
supernova type. We examine separately SN II, SN IIn, SN IIb, SN Ib, SN Ic, and
SN Ic with broad lines (SN Ic-BL). Type Ic SN explode at small host offsets,
and their hosts have exceptionally strongly star-forming, metal-rich, and dusty
stellar populations near their centers. The SN Ic-BL and SN IIb explode in
exceptionally blue locations, and we find that their host galaxies have lower
oxygen abundance than the hosts of their respective close spectroscopic
cousins, SN Ic and SN Ib. The host galaxies of SN Ic-BL also exhibit strong
central specific star formation rates. In contrast, we find no strong evidence
for different environments for SN IIn compared to the sites of SN II. We take
account of the source of the supernova discoveries, whether from targeted
searches or from galaxy-impartial surveys, and show that these results are
robust.
View original:
http://arxiv.org/abs/1110.1377
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