Neutrino oscillation in a magnetized gamma-ray burst fireball

Abstract

Neutrinos of energies of about 5-20 MeV are produced due to the stellar collapse or merger events that trigger the gamma-ray burst. Also low energy MeV neutrinos are produced within the fireball due to electron-positron annihilation and nucleonic bremsstrahlung. Many of these neutrinos will propagate through the dense and relativistic magnetized plasma of the fireball. We have studied the possibility of resonant oscillation of nu(e) <-> nu(mu,tau) by taking into account the neutrino oscillation parameters from SNO, super Kamiokande, and liquid scintillator detector. Using the resonance condition, we have calculated the resonance length for these neutrinos and also for the fireball observables, like lepton asymmetry and the baryon load that are estimated based on the assumed fireball radius of 100 km.