  We revisit the possibility that neutrinos undergo non-radiative decay. We
investigate the potential to extract information on the neutrino
lifetime-to-mass ratio from the diffuse supernova neutrino background. To this
aim, we explicitly consider the current uncertainties on the core-collapse
supernova rate and the fraction of failed supernovae. We present predictions in
a full 3 neutrino framework in the absence and presence of neutrino
non-radiative decay, for the Super-Kamiokande+Gd, the JUNO, the
Hyper-Kamiokande, and the DUNE experiments, that should observe the diffuse
supernova neutrino background in the near future. Our results show the
importance of a 3 neutrino treatment of neutrino decay and of identifying the
neutrino mass ordering to break possible degeneracies between DSNB predictions
in the presence of decay and standard physics.
