A comparison of traditional and hybrid radiation detector dead-time models and detector behavior

Abstract

High intensity radiation measurements are confounded by detector dead-time and pulse pile-up problems. A computational method was used to compare the traditional dead-time models with recently proposed hybrid dead-time models. A computational algorithm based on a decay source method was used to study the behavior of various dead-time models. Validation of the code was performed for the hybrid models by confirming that the predictions lie between the two ideal dead-time models; the paralyzing and the non-paralyzing model. It was interesting to note that two seemingly similar hybrid dead-time models produced significantly different results. Lee and Gardner's model based on two dead-times and Patil and Usman paralysis factor based model are inherently different in their logic as well as results. For Lee and Gardner's model altering the orders of dead-times produced significantly different response. These hybrid models should be studied further to investigate both the dependence and the variation of model parameters on detector design and operating conditions. It is well accepted that one dead-time does not apply to all detectors and even for the same detector applicability of the same model under all operating condition is questionable. Therefore, dead-time model should be chosen carefully for the specific detector, operating conditions and radiation to be measured to correctly represent the physical measurement phenomenon.