First results from DAMA/LIBRA

Abstract

The highly radiopure 250 kg NaI(Tl) DAMA/LIBRA set-up is running at the Gran Sasso National Laboratory of the I.N.F.N.. The first results obtained by exploiting over four annual cycles the model independent annual modulation signature for Dark Matter (DM) particles confirm those of the former DAMA/NaI. In particular, the DAMA/NaI and DAMA/LIBRA data satisfy all the many peculiarities of the DM annual modulation signature. Neither systematic effects nor side reactions able to account for the observed modulation amplitude and to contemporaneously satisfy all the several requirements of the DM signature are available. Considering the former DAMA/NaI and the present DAMA/LIBRA data all together (total exposure 0.82 ton×yr), the presence of Dark Matter particles in the galactic halo is supported at 8.2 σ C.L. Identification of dark matter