SCINTILLATION SPECTROSCOPY FOR BETA-RAY DOSE MEASUREMENTS

Two methods have been developed and tested for the measurement of beta ray dose with a scintillation probe. According to the first method th e energy absorbed in plastic filters is calculated from the difference between the energy E of the incident and filtered beta spectrum with an expression of the type E similar to c Sigma iN(i)Delta m, where c i s a calibration constant (keV per channel), i is the channel number, N (i) is the detected beta spectrum, and Delta m is the filter thickness . According to the second 'dE/dx' method the energy deposited in the s urface layer of the scintillator is calculated by E similar to c Sigma dE/dx(i)N(i), where dE/dx is the specific energy loss for tissue-equi valent media. The methods were tested for the cases of normally incide nt electrons and surface contamination. The scintillation probe used i s stilbene and the test sources are thin Sr-90/Y-90 and Cs-137. The re sults are close to the expected doses as calculated by Monte Carlo sim ulations.