High volume sampler-semiconductor spectrometer arrangement for ambient air gamma absorbed dose measurements

摘要

A method is developed to measure total gamma absorbed dose rate from distributed radionuclides in ambient air. The method involves concentration of radionuclides on a filter paper, using high volume sampler, measurement of count rates on axil line; determination of the average energy and the average absolute efficiency corresponding to peaks in the energy range by Das Mahapatra method; determination of the average energy and the average absolute efficiency. The total activity is determined from the ratio of the gross count rate and the average efficiency for use in the commutation of the total absorbed dose rate. The sum of the absorbed dose rates determined for individual energy peaks is shown to agree with the one calculated using our new method and similar results available in literature. The method can be used to find out the total absorbed dose rates without detailed analysis of contributions of the energy peaks of members the natural radioactive series, 40{sup left}K, 137{sup left}Cs, 60{sup left}Co etc., which usually exceed fifty in number.