Supernovae and their host galaxies - III. The impact of bars and bulges
  on the radial distribution of supernovae in disc galaxies
  We present an analysis of the impact of bars and bulges on the radial
distributions of the different types of supernovae (SNe) in the stellar discs
of host galaxies with various morphologies. We use a well-defined sample of 500
nearby (< 100 Mpc) SNe and their low-inclined (i < 60 deg) and morphologically
non-disturbed S0-Sm host galaxies from the Sloan Digital Sky Survey. We find
that in Sa-Sm galaxies, all core-collapse (CC) and vast majority of SNe Ia
belong to the disc, rather than the bulge component. The radial distribution of
SNe Ia in S0-S0/a galaxies is inconsistent with their distribution in Sa-Sm
hosts, which is probably due to the contribution of the outer bulge SNe Ia in
S0-S0/a galaxies. In Sa-Sbc galaxies, the radial distribution of CC SNe in
barred hosts is inconsistent with that in unbarred ones, while the
distributions of SNe Ia are not significantly different. At the same time, the
radial distributions of both types of SNe in Sc-Sm galaxies are not affected by
bars. We propose that the additional mechanism shaping the distributions of
Type Ia and CC SNe can be explained within the framework of substantial
suppression of massive star formation in the radial range swept by strong bars,
particularly in early-type spirals. The radial distribution of CC SNe in
unbarred Sa-Sbc galaxies is more centrally peaked and inconsistent with that in
unbarred Sc-Sm hosts, while the distribution of SNe Ia in unbarred galaxies is
not affected by host morphology. These results can be explained by the distinct
distributions of massive stars in the discs of early- and late-type spirals.
