26-30 October 2015
Asia/Tokyo timezone

Neutrino Flavor Ratios Modified by Cosmic Ray Secondary-acceleration

29 Oct 2015, 17:40
Room 3.4 ()

Room 3.4

Oral presentation Neutrino physics Neutrinos


Dr Norita Kawanaka (The University of Tokyo)


Acceleration of 's and 's modies the flavor ratio at Earth (at astrophysical sources) of neutrinos produced by pion decay, nu_e : nu_mu : nu_tau , from 1 : 1 : 1 (1 : 2 : 0) to 1 : 1:8 : 1:8 (0 : 1 : 0) at high energy, because pions decay more than muons during secondary-acceleration. The neutrino spectrum accompanies a flat excess, differently from the case of energy losses. With the flavor spectra, we can probe timescales of cosmic-ray acceleration and shock dynamics. We obtain general solutions of convection-diffusion equations and apply to gamma-ray bursts, which may have the flavor modication at around PeV - EeV detectable by IceCube and next-generation experiments.

Primary author

Dr Norita Kawanaka (The University of Tokyo)


Presentation Materials