A Prototype of LaBr3:Ce in situ Gamma-Ray Spectrometer for Marine Environmental Monitoring

摘要

A prototype of LaBr3:Ce in situ gamma-ray spectrometer for marineenvironmental monitoring is developed and applied for in situ measurement. A3-inch LaBr3:Ce scintillator is used in the detector, and a digital pulseprocess electronics is chosen as the pulse height analyzer. For this prototype,the energy response of the spectrometer is linear and the energy resolution of662keV is 2.6% (much better than NaI). With the measurement of the prototype ina water tank filled with 137Cs, the detect efficiency for 137Cs is (0.2880.01)cps/(Bq/L), which is close to the result of Monte Carlo simulation,0.283cps/(Bq/L). With this measurement, the MDAC for 137Cs in one hour has beencalculated to 0.78Bq/L, better than that of NaI(Tl) in-situ gamma spectrometer,which is ~1.0Bq/L.