High energy neutrinos from choked GRBs and their flavor ratio measurement by the IceCube

Abstract

The high energy neutrinos produced in a choked GRB can undergo matter oscillation before emerging out of the stellar envelope. Before reaching the detector on Earth, these neutrinos can undergo further vacuum oscillation and then Earth matter oscillation. In the context of IceCube we study the Earth matter effect on neutrino flux in the detector. For the calculation of track-to-shower ratio R in the IceCube, we have included the shadowing effect and the additional contribution from the muon track produced by the high energy tau lepton decay in the vicinity of the detector. We observed that R is different for different CP phases in vacuum but the matter effect suppresses these differences. We have also studied the behavior of R when the spectral index $\alpha$ varies.