LAUSR

Abstract This article describes an attempt to estimate the background (BG) pulse height spectrum (PHS) of the CeBr3 scintillation spectrometer due to terrestrial gamma ray components. In radiological emergencies, there are some cases which the prior measurement of the background components can't be made. By subtracting the BG components from the measured gross PHS, timely and accurate information about the artificial radionuclides involved in the emergencies would be effectively drawn to protect the member of the public and first responders. A Monte Carlo calculation was conducted to simulate the PHS by gamma rays from natural radionuclides uniformly distributed in the ground. The calculated PHS were verified to be consistent with measured PHS. Derived dose equivalent rate from the calculated PHS were compared with reference value and found to be in good agreement with each other. The study revealed that applying the calculated PHS to the in-situ gamma ray spectrometry components hardly affected the determination of surface deposition density on soil for radioactive cesium.