Ultra High Energy $\nu_\tau$ Detection Using Cosmic Ray Tau Neutrino   Telescope Used in Fluorescence/Cerenkov Light Detection
  We have investigated the possibility of $\nu_\tau$ detection using Cosmic Ray Tau Neutrino Telescope (CRTNT) based on air shower fluorescence/Cerenkov light detector techniques. This approach requires an interaction of a $\nu_\tau$ with material such as a mountain or the earth's crust. $\tau$ lepton produced in the charged current interaction must escape from the earth and then decay and initiate a shower in the air. The probability for the conversion from $\nu_\tau$ to air shower has been calculated for an energy range from 1 PeV to 10 EeV. An air shower simulation program has been developed using the simulation package Corsika. The trigger efficiency has been estimated for a CRTNT detector similar to the HiRes/Dice detector in the shadow of Mt. Wheeler in Nevada, USA. A rate of about 8 triggered events per year is expected for the AGN neutrino source model with an optimized configuration and duty cycle of the detector. 
Z. Cao, M. A. Huang, P. Sokolsky and Y. Hu