Decay of High-Energy Astrophysical Neutrinos

Abstract

Existing limits on the nonradiative decay of one neutrino to another plus a massless particle (e.g., a singlet Majoron) are very weak. The best limits on the lifetime to mass ratio come from solar neutrino observations and are [Formula presented] for the relevant mass eigenstate(s). For lifetimes even several orders of magnitude longer, high-energy neutrinos from distant astrophysical sources would decay. This would strongly alter the flavor ratios from the [Formula presented] expected from oscillations alone and should be readily visible in the near future in detectors such as IceCube. © 2003 The American Physical Society.