M. T. Botticella, S. J. Smartt, R. C. Kennicutt Jr., E. Cappellaro, M. Sereno, J. C. Lee
The core collapse supernova (CCSN) rate provides a strong lower limit for the
star formation rate (SFR). Progress in using it as a cosmic SFR tracer requires
some confidence that it is consistent with more conventional SFR diagnostics in
the nearby Universe. This paper compares standard SFR measurements based on
Halpha, FUV and TIR galaxy luminosities with the observed CCSN rate in the same
galaxy sample. The comparison can be viewed from two perspectives. Firstly, by
adopting an estimate of the minimum stellar mass to produce a CCSN one can
determine a SFR from SN numbers. Secondly, the radiative SFRs can be assumed to
be robust and then the SN statistics provide a constrain on the minimum stellar
mass for CCSN progenitors. The novel aspect of this study is that Halpha, FUV
and TIR luminosities are now available for a complete galaxy sample within the
local 11Mpc volume and the number of discovered SNe in this sample within the
last 13 years is high enough to perform a meaningful statistical comparison. We
exploit the multi-wavelength dataset from 11HUGS, a volume-limited survey
designed to provide a census of SFR in the local Volume. Assuming a lower limit
for CCSN progenitors of 8 Msun, the CCSN rate matches the SFR from the FUV
luminosity. However the SFR based on Halpha luminosity is lower than these two
estimates by a factor of nearly 2. If we assume that the FUV or Halpha based
luminosities are a true reflection of the SFR, we find that the minimum mass
for CCSN progenitors is 8 +/- 1 Msun, and 6 +/- 1 Msun, respectively. The
estimate of the minimum mass for CCSN progenitors obtained exploiting FUV data
is in good agreement with that from the direct detection of CCSN progenitors.
The concordant results by these independent methods point toward a constraint
of 8 +/- 1 Msun on the lower mass limit for progenitor stars of CCSNe.
View original:
http://arxiv.org/abs/1111.1692
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