Study on the back scattering gamma spectra of hpge detector by using MCNP code

Abstract

In this work, the simulation of back-scattering gamma spectra of HPGe detector was carried out with using MCNP code. The simulation was made with the 316.5 keV peak of the spherical source of Ir-192 which was housed in a collimator. When increasing the scattering angle from 60 degrees to 120 degrees, with the aluminum target placed at  angles of 30 and 45 degrees  to the incident beam, the spectra show that the single scattering component increases and the multi scattering component decreases. The single scattering peak increases when increasing the thickness of the target and saturates at the thickness of 1 centimeter. These results are the base for getting the best condition while applying this method in testing densities or thickness of the sample and finding sample defects.