The Institute for Reference Materials and Measurements (IRMM) in Geel was a pioneering laboratory in performing radioactivity measurements underground. In the underground laboratory HADES, located 225 m underground at the premises of the Belgian nuclear centre SCK•CEN, the muon flux is 4 orders of magnitude lower than at surface. This reduction of the natural background radiation is very important in gamma-ray spectrometry. IRMM has worked on developing underground measurement techniques and to implement the developments in projects in support of EU-policies in a wide range of fields.
This seminar will explain the problems and possibilities of performing measurements underground and give examples of projects where these measurements were important like in retrospective dosimetry (Tokai-mura accident in 1999 and Hiroshima), measurements of very rare decays (lowest decay energy known to man and Nature's rarest isotope), environmental radioactivity, activation cross section measurements and work in collaborations with large scale experiments like the solar neutrino experiment Borexino and double beta decay experiment GERDA.