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arXiv · 0806.2126

UHE tau neutrino flux regeneration while skimming the Earth

Oscar Blanch Bigas·Olivier Deligny·Kévin Payet·Véronique Van Elewyck
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Abstract

The detection of Earth-skimming tau neutrinos has turned into a very promising strategy for the observation of ultra-high energy cosmic neutrinos. The sensitivity of this channel crucially depends on the parameters of the propagation of the tau neutrinos through the terrestrial crust, which governs the flux of emerging tau leptons that can be detected. One of the characteristics of this propagation is the possibility of regeneration through multiple $ν_τ\leftrightarrow τ$ conversions, which are often neglected in the standard picture. In this paper, we solve the transport equations governing the $ν_τ$ propagation and compare the flux of emerging tau leptons obtained allowing regeneration or not. We discuss the validity of the approximation of neglecting the $ν_τ$ regeneration using different scenarios for the neutrino-nucleon cross-sections and the tau energy losses.

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Oscar Blanch Bigas, Olivier Deligny, Kévin Payet, Véronique Van Elewyck. 2008-09-08. UHE tau neutrino flux regeneration while skimming the Earth. https://doi.org/10.1103/physrevd.78.063002

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