Independent Simulations of the Performance of the 3.8m Cangaroo TeV Imaging Telescope for Pulsar Studies

John Patterson

University of Adelaide

The lack of a southern hemisphere "standard candle" at TeV energies makes it necessary to use Monte Carlo simulations to find the characteristics of the ground based CANGAROO TeV Gamma Ray telescope. From these simulations the energy threshold and collection area of the telescope as a function of energy and zenith angle can be predicted and the values of various image parameter cuts used in the data analysis can be obtained a priori. No statistical penalties then apply in the calculation of the significance of a detected source. Using the Hillas Mocca 92 Monte Carlo program at Adelaide, we have performed independent simulations on the 3.8m CANGAROO TeV gamma ray telescope and have compared them with the calculations of Japanese team members using the GEANT version 3.15 simulation program developed at CERN. In particular, we have sought to include the effect of a cosmic ray composition above $\sim$1 TeV which includes protons, and helium, carbon, nitrogen and oxygen nuclei. Performance characteristics as mentioned above have been found; the effect of background skynoise studied, and a quality factor for gamma ray detection has been calculated.