Attempt to estimate the background pulse height spectrum of the CeBr scintillation spectrometer due to terrestrial gamma ray components; Application in environmental radiation monitoring

Kowatari, Munehiko; Tanimura, Yoshihiko   ; Kessler, P.*; Rttger, A.*

In radiological emergency, timely and reliable radiological information such as dose rate or radioactive concentrations due to artificial radionuclides is indispensable to protect general public and the first responder of the situation. The authors have investigated the method for effectively identifying and determining the radioactivity concentration using a scintillation spectrometer. In this study, the authors demonstrate how influence of terrestrial background (BG) component on measured pulse height spectrum can be minimized to obtain the peaks from gamma rays emitted by artificial radioactivity. In some cases of radiological emergency monitoring, subtraction of BG components was probe to be difficult, because the prior measurement of BG component at the place to be monitored is compulsory. By removing the BG component appropriately from measured pulse height spectrum without any prior BG measurement, the effective minimum detection limit of the spectrometer would be declined.