Coherence of Supernova Neutrinos

Abstract We show that supernova neutrinos have extremely small wave packets compared to neutrinos from other sources and study possible consequences. In simple examples it turns out that the experimentally observable oscillation probability does not depend on the size of the wave packets but the energy spectrum may be affected. The coherence length can be increased beyond the usual estimate, if neutrinos travel through matter with a non-adiabatically changing density.