Low Background Gamma-Ray Spectrometry in the “Laboratoire Souterrain de Modane”

. Most of the underground experiments in physics and many studies in geology, biology or environmental sciences face a common requirement with the necessity of using experimental devices with ultra-low background radioactivity. Many developments involving many different techniques have been used in order to be able to measure extremely low levels of radioactivity in materials. This report will focus on low background gamma ray spectrometry and will describe the work which has been carried out over the last fifteen years in the “Laboratoire Souterrain de Modane” (LSM)