Radiopurity requirements for the SuperNEMO experiment and the BiPo detector

The main goal of the SuperNEMO collaboration is to try to observe neutrinoless double-β decay. This would prove that the neutrino is a Majorana particle (ν = ν-bar). Today the best lower limits on half-lives of this process are set around 10²⁴ - 10²⁶ years as obtained by the NEMO-3 experiment [1] (for the 2β isotope ¹⁰⁰Mo) and other experiments. SuperNEMO is the next generation experiment based on the NEMO-3 tracker-calorimeter detection principle. The targeted contamination levels for the source foils are lower than can be measured through γ spectroscopy. A more sensitive detector has been constructed to measure low contaminations in ²⁰⁸Tl (around few μBq/kg) and ²¹⁴Bi (few dozen μBq/kg) in thin materials: the BiPo detector. BiPo-3 has been fully operational at the Laboratorio Subterráneo de Canfranc (LSC) since January, 2013. The construction, performance and calibration of the BiPo-3 detector will be covered as well as the radiopurity requirements for SuperNEMO. (paper)