Constraints on the Star Formation Rate from Supernova Relic Neutrino   Observations
  We discuss the implication of the observation of supernova relic neutrinos on the study of the star formation rate (SFR) in galaxies. The limit recently obtained at Super-Kamiokande (SK) is already marginally significant: The SFR we derived $\psi(t_0)<0.040M_{\odot}$yr$^{-1}$Mpc$^{-3}$(at a 90% CL) is about twice the SFR estimated from radio observations, and five times the rate from H$\alpha$ allowing for uncertainties in the model supernova neutrino flux. 
M. Fukugita and M. Kawasaki