Detection of Earth-skimming UHE tau neutrino with the JEM-EUSO detector

TL;DR

This paper assesses the feasibility of detecting ultra-high-energy tau neutrinos skimming the Earth using the JEM-EUSO space-based detector, focusing on tau interactions, propagation, and detection prospects.

Contribution

It provides a detailed estimation of the detection capabilities of JEM-EUSO for Earth-skimming tau neutrinos, including modifications to simulation tools for this purpose.

Findings

Detection is feasible if tau decay occurs below ~5 km altitude.

The geometrical aperture for Earth-skimming neutrinos has been estimated.

Simulation tools were adapted to evaluate detection prospects.

Abstract

The ultra high energy cosmic neutrinos are powerful astrophysical probes for both astrophysical mechanisms of particle acceleration and fundamental interactions. They open a window into the very distant and high-energy Universe that is difficult to access by any human means and devices. The possibility of detecting them in large exposure space-based apparatus, like JEM-EUSO, is an experimental challenge. In this paper we present an estimation of the feasibility of detection of UHE tau neutrino by the JEM-EUSO telescope. The interactions of tau-neutrino in sea water and Earth's crust have been investigated. The estimation of the propagation length and energy of the outgoing tau-lepton shows that if its decay occurs in the atmosphere close enough to the Earth's surface, e.g. below $\sim$ $5 km$ altitude, the cascade is intensive enough and the generated light can be detected from space. We have evaluated the geometrical aperture of the JEM-EUSO detector for the Earth-skimming (horizontal and upward-going) tau-neutrinos by making specific modifications to the standard CORSIKA code and developing an interface to the existing ESAF (EUSO Simulation and Analysis Framework) software.