Dense neutrino oscillations : beyond two flavor

In a dense supernova environment, neutrinos can undergo flavor conversions known as the collective oscillations. These self induced neutrino flavor conversions (collective oscillations) are almost exclusively studied in the standard two flavor scenario. We study these oscillations in the complete three flavor scenario. The ‘fast’ conversions are fascinating distinctions of the dense neutrino systems. In the fast modes the collective oscillation dynamics are independent of the neutrino mass, growing at the scale of the large neutrino-neutrino interaction strength (10 5 km −1 ) of the dense core. This is extremely fast, as compared to the usual ‘slow’ collective modes driven by much smaller vacuum oscillation frequencies (10 0 km −1 ). We perform the first non-linear simulations of fast conversions in the presence of three neutrino flavors which is motivated from the recent supernova simulations with muon production. We relax the standard ν μ , τ = ν ¯ μ , τ (two-flavor) assumption. Our results show the significance of muon and tau lepton number angular distributions, together with the traditional electron lepton number ones and thus explain the need for a complete three flavor analysis.