Fast Flavor Depolarization of Supernova Neutrinos

Flavor-dependent neutrino emission is critical to the evolution of a supernova and its signal. In dense anisotropic interior star, neutrino-neutrino forward scattering can lead fast collective oscillations, which has striking consequences. We present theory flavor depolarization, explaining how differences become smaller, i.e., depolarize, due diffusion smaller angular scales. show that transverse relaxation determines epoch this irreversible depolarization. give method compute depolarized fluxes, presenting an explicit formula for simple initial conditions, be crucial input phenomenology.