Monte Carlo techniques for in-situ specific activity estimation of radionuclides with a portable coaxial HPGe: preliminary results.

In this work, gamma-ray spectrometry with HPGe detectors is used to measure radionuclides' specific activity (A) in soils. The main purpose of the paper is to present a general procedure to assess A in soils from in-situ acquisitions. The soil from two experimental sites was analyzed both in the field, with a portable HPGe detector, and in the laboratory, with a BEGe detector. Sample analysis in the laboratory provided a benchmark for the values of soil's A since it is easier to measure. Monte Carlo simulations were employed to obtain detectors' efficiency at different gamma-ray energies and allowed to assess radionuclides' A from in-situ acquisitions. Finally, the applicability and limitations of this procedure are discussed.