A comparison between star formation rate diagnostics and rate of core collapse supernovae within 11 Mpc

Abstract

Aims. The core collapse supernova 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 Hα, far ultraviolet (FUV) and total infrared (TIR) galaxy luminosities with the observed core collapse supernova 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 core collapse supernova one can determine a SFR from supernova numbers. Secondly, the radiative SFR can be assumed to be robust and then the supernova statistics provide a constrain on the minimum stellar mass for core collapse supernova progenitors. Methods. The novel aspect of this study is that Hα, FUV and TIR luminosities are now available for a complete galaxy sample within the local 11 Mpc volume and the number of discovered supernovae in this sample within the last 13 years is high enough to perform a meaningful statistical comparison. We exploit the multi-wavelength dataset from 11 HUGS, a volume-limited survey designed to provide a census of SFR in the Local Volume. There are 14 supernovae discovered in this sample of galaxies within the last 13 years. Although one could argue that this may not be complete, it is certainly a robust lower limit. Results. Assuming a lower limit for core collapse of 8 M ⊙ (as proposed by direct detections of SN progenitor stars and white dwarf progenitors), the core-collapse supernova rate matches the SFR from the FUV luminosity. However, the SFR based on Hαa luminosity is lower than these two estimates by a factor of nearly 2. If we assume that the FUV or Hα based luminosities are a true reflection of the SFR, we find that the minimum mass for core collapse supernova progenitors is 8 ± 1 M ⊙ and 6 ± 1 M ⊙, respectively. Conclusions. The estimate of the minimum mass for core collapse supernova progenitors obtained exploiting FUV data is in good agreement with that from the direct detection of supernova progenitors. The concordant results by these independent methods point toward a constraint of 8 ± 1 M 1⊙ on the lower mass limit for progenitor stars of core collapse supernovae. © 2012 ESO.