Massive Majorana neutrinos in prebounce supernovae

Abstract

The currently accepted models of supernova collapse rely on the standard electroweak theory and massless left-handed neutrinos. We consider the effect of massive right-handed Majorana neutrinos on this scenario. In order that they do not upset the agreement of the usual treatment with observation, we require that in the prebounce stage either (a) these neutrinos are trapped or (b) if they free stream they do not change the electron fraction to the extent that the explosion is prevented. From these constraints, we obtain upper and lower bounds on the right-handed interaction strengths as a function of the neutrino mass, which can be translated to bounds on the right-handed gauge-boson mass.