SYSTEME DE MESURE DE LA RADIOACTIVITE DANS UN BRUIT DE FOND GAMMA

摘要

A method and a device for compensation-based measurement of the alpha and/or beta radioactivity in a gamma background noise comprising a compensation probe comprises a first sensor allowing the measurement of the alpha and/or beta and gamma radioactivity and a second sensor not allowing the measurement of the alpha and/or beta radioactivity but allowing the measurement of the gamma radioactivity; wherein the sensors are arranged to be exposed substantially to the same gamma background noise; measurement biases being associated with the geometric arrangement of the sensors on account of the anisotropy of the gamma radiation; the measurement system determines the alpha and/or beta radioactivity by compensation comprising a subtraction between the measurement of alpha and/or beta and gamma radioactivity and the gamma measurement, the compensation minimizing the measurement biases associated with the geometric arrangement of the sensors. Other developments are described to improve the reliability of the radioactivity measurements.