NEMO 3 experiment: preliminary results from 2003 data

The NEMO-3 detector installed in the Modane Underground Laboratory (LSM, France) is running to search for neutrinoless double beta decay ($\beta \beta 0\nu$) with an expected sensitivity for the effective Majorana neutrino mass down to 0.1 eV. New preliminary limits (90% CL), $T_{1\mathrm{/}2}(\beta \beta 0\nu )>1.0\cdot {10}^{23}$ y (massive mechanism) and $T_{1\mathrm{/}2}(\beta \beta 0\nu )>1.9\cdot {10}^{23}$ y (right-handed currents) were established analyzing ${}^{100}$Mo data collected during 3800h of measurements in 2003. This is the world’s best result for ${}^{100}$Mo. New preliminary half-lives of $\beta \beta 2\nu$-mode for ${}^{100}$Mo, ${}^{82}$Se, ${}^{116}$Cd, ${}^{150}$Nd are also reported as well as the results of background studies. The future progress and plans of the NEMO-3 project are discussed.