Probing Neutrino Flavor Transition Mechanism with Ultra High Energy Astrophysical Neutrinos

Understand

Observation of ultra-high energy astrophysical neutrinos and identification of their flavors have been proposed for future neutrino telescopes.

• The flavor ratio of astrophysical neutrinos observed on the Earth depends on both the initial flavor ratio at the source and flavor transitions taking place during propagations of these neutrinos.
• The flavor transition mechanisms are well-classified with our model-independent parametrization.
• We find a new parameter R={\phi}_e/({\phi}_{\mu} + {\phi}_{\tau}) can probe directly the flavor transition in the framework of our model-independent parametrization, without the assumption of the {\nu}_{\mu}-{\nu}_{\tau} symmetry.