New DAMA results on WIMP search with large mass highly radiopure NaI(Tl) at Gran Sasso

The ~= 100 kg NaI(Tl) DAMA set-up - running at the Gran Sasso National Laboratory of I.N.F.N. - is mainly devoted to the search for the WIMP annual modulation signature. This modulation, due to the Earth's motion around the Sun, would induce - according to the standard WIMP model - a rate variation of ~= 7% between the two extreme conditions. Results obtained with a statistics of 4549 kgcdotday have been previously published. Here we present new results (obtained by analysing a further statistics of 14962 kgcdotday), which support the presence of a yearly modulation in the low energy experimental rate and are consistent - in terms of possible WIMP candidate - with the ones previously achieved. A maximum likelihood analysis, combining the two running periods (total statistics of 19511 kgcdotday), favours the hypothesis of presence of an annual modulation at 99.6% C.L., giving for the possible candidate a mass of (59^{+17}_{-14}) GeV and a scalar cross section on proton (7.0^{+0.4}_{-1.2})10^{-6} pb. Quantitative investigations of possible sources of systematics will be commented.