From SNO to SNO+, upgrading a neutrino experiment

SNO+ is a multi-purpose neutrino experiment in construction in SNOLAB, Canada, the deepest underground laboratory. It succeeds the SNO experiment, replacing heavy water by liquid scintillator and thus lowering the sensitivity to a lower energy threshold. SNO+ will study low energy solar neutrinos, including those from the pep and CNO cycles. Loading the liquid scintillator with almost a ton of Neodymium will then enable the search for neutrinoless double beta decay. SNO+ also aims at detecting reactor, geo- and possibly supernova neutrinos. All the components of the detector must reach and maintain a very high level of radiopurity. I will discuss in detail the calibration programme that has been developed for SNO+ and that must at all time keep in mind these radiopurity requirements.