First results of the NEMO3 experiment

The objective of the NEMO Collaboration is to search for neutrinoless double beta decay and thus to investigate physics beyond the Standard Model. The expected sensitivity for the effective neutrino mass is on the order of 0.1 eV. The NEMO-3 detector has been operating in the Fréjus Underground Laboratory and has been collecting data since February of 2003. The half-life of two-neutrino double beta decay has been measured for 100Mo and 82Se. Constraints on the background for neutrinoless double beta decay have been set. PACS: 23.40.-s Beta decay; double beta decay; electron and muon capture – 14.60.Pq Neutrino mass and mixin