Oscillations and propagation of neutrinos through magnetized Gamma-Ray Burst fireball

Abstract

We calculate explicitly the effective potentials for different backgrounds which may be helpful in different environments with/without magnetic field. By considering the mixing of three active neutrinos in the medium with the weak magnetic field, we show the survival and conversion probabilities of neutrinos from one flavor to another with the resonance condition, when neutrinos are propagating through the dense and relativistic plasma of the Gamma-Ray Burst fireball. These MeV neutrinos are produced due to stellar collapse or merger events which trigger the Gamma-Ray Burst. The fireball itself also produces MeV neutrinos due to electron positron annihilation, inverse beta decay and nucleonic bremsstrahlung. Using the three neutrino mixing and considering the best fit values of the neutrino parameters, we found that electron neutrinos are hard to oscillate to another flavors. On the other hand, the muon neutrinos and the tau neutrinos oscillate with equal probability to one another, which depends on the neutrino energy, temperature and size of the fireball. Comparison of oscillation probabilities with and without magnetic field shows that, they depend on the neutrino energy and also on the size of the fireball. By using the resonance condition, we have also estimated the resonance length of the propagating neutrinos as well as the baryon content of the fireball. © 2010 American Institute of Physics.