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arXiv · 1308.1828

Probing Neutrino Flavor Transition Mechanism with Ultra High Energy Astrophysical Neutrinos

Abstract

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=ϕ_e/(ϕ_μ + ϕ_τ) can probe directly the flavor transition in the framework of our model-independent parametrization, without the assumption of the ν_μ-ν_τ symmetry. A few flavor transition models are employed to test our parametrization with this new observable. The observational constraints on flavor transition mechanisms by the new observable is discussed through our model-independent parametrization.

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Kwang-Chang Lai, Guey-Lin Lin, Tsung-Che Liu. 2013-08-30. Probing Neutrino Flavor Transition Mechanism with Ultra High Energy Astrophysical Neutrinos. https://doi.org/10.1103/physrevd.89.033002

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