Ground Gamma-ray survey by HPGe: Numerical simulations and comparison between field and laboratory measurements

A comparison between two methodologies for environmental gamma-ray spectrometry were carried out. Laboratory analyses on soil samples were used to test the accuracy of a hand-held portable instrument. Numerical simulations were performed to calibrate detectors and evaluate the actual response of the instrument in the field. Measurements were carried out in a volcanic area, in order to detect the presence of natural radionuclides such as ²³⁸U and ²³²Th chains daughters and ⁴⁰K. Results show a good agreement between the two methodologies. Some discrepancies are correlated to the presence of vegetation in the monitoring area, and can give a proxy to infer the presence of ²²²Rn degassing.