Astrophysics LETTERS Effect of resonant neutrino oscillation on TeV neutrino flavor ratio from choked

Abstract In the collapsar scenario of the long duration Gamma-Ray Bursts (GRBs), multi-TeV neutrino emission is predicted as the jet makes its way through the stellar envelope. Such a neutrino signal is also expected for more general “failed ” GRBs in which a putative jet is “choked ” by a heavy envelope. If the νe → νµ neutrino oscil-lation parameters are in the atmospheric neutrino oscillation range, we show that the resonant oscillation of νe ↔ νµ,τ can take place within the inner high density region of the choked jet progenitor with a heavy envelope, altering the ν flavor ratio on its surface to Φsνe:Φ s νµ:Φ s ντ =5:11:2. Considering vacuum oscillations of these neutrinos on their way to Earth, the final flavor ratio detected on Earth is further modified to either 1:1.095:1.095 for the large mixing angle solution to the solar neutrino data, or 1:1.3:1.3 for maximal mixing among the muon and tau neutrinos in the vacuum. Key words: gamma rays: bursts