Shower spectrum from earth skimming Tau-neutrinos

A Monte-Carlo simulation code for the interactions and propagations of neutrinos and leptons at energy greater than 10¹⁴ eV inside the Earth is developed. Details of this code are described. This code can be used for underground or above-ground neutrino telescopes. Using this simulation code, we study the shower spectrum initiated by the decays of tau-leptons, which are produced from the Earth-skimming tau neutrinos through charged current interactions. Two neutrino flux predictions (AGN and GZK) are used in this study. Results show that the shower energy are in between For AGN neutrinos, the shower energy are mostly in between 3×10¹⁴ eV to 10 ¹⁴ eV for AGN neutrinos and in between 10¹⁴ eV to 10 ¹⁴ eV for GZK neutrinos. The detector technology still needs many improvements to detect these neutrinos.