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Many experimental observations and theoretical arguments have pointed out that a large fraction of the Universe is composed by Dark Matter particles. Many possibilities are open on the nature and interaction types of such relic particles. In particular, this paper summarizes the main results obtained by exploiting the model independent Dark Matter annual modulation signature for the presence of Dark Matter particles in the galactic halo by DAMA experiment. [ABSTRACT FROM AUTHOR]

The DAMA/LIBRA experiment (∼ 250 kg sensitive mass composed by highly radio-pure NaI(Tl)) is in data taking in the underground Laboratory of Gran Sasso (LNGS). Its first phase (DAMA/LIBRA-phase1) and the former DAMA/NaI experiment (∼ 100 kg of highly radio-pure NaI(Tl)) collected data for 14 independent annual cycles, exploiting the model-independent Dark Matter (DM) annual modulation signature (total exposure 1.33 ton × yr). A DM annual modulation effect has been observed at 9.3 σ C.L., supporting the presence of DM particles in the galactic halo. No systematic or side reaction able to mimic the observed DM annual modulation has been found or suggested by anyone. Recent analyses on possible diurnal effects, on the Earth shadowing effect and on possible interpretation in terms of Asymmetric Mirror DM will be mentioned. At present DAMA/LIBRA is running in its phase2 with increased sensitivity. [ABSTRACT FROM AUTHOR]

The DAMA project develops and uses new/improved low background scintillation detectors to investigate the Dark Matter (DM) particle component(s) in the galactic halo and rare processes deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N.. Here some highlights of DAMA/LIBRA (Large sodium Iodide Bulk for Rare processes) as a unique apparatus in direct DM investigation for its full sensitive mass, target material, intrinsic radio-purity, methodological approach and all the controls performed on the experimental parameters are outlined. The DAMA/LIBRA-phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton × yr, corresponding to 14 annual cycles) have reached a model-independent evidence at 9.3 σ C.L. for the presence of DM particles in the galactic halo exploiting the DM annual modulation signature with highly radio-pure NaI(Tl) target. Some of the perspectives of the presently running DAMA/LIBRA-phase2 are summarised and the powerful tools offered by a model independent strategy of DM investigation are pointed out. [ABSTRACT FROM AUTHOR]

The results obtained with the total exposure of 1.04 ton x yr collected by DAMA/LIBRA--phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles are summarized. The DAMA/LIBRA--phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton x yr, corresponding to 14 annual cycles) give evidence at 9.3 σ C.L. for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model independent DM annual modulation signature by using highly radio-pure NaI(Tl) target. No systematic or side reaction able to mimic the exploited DM signature has been found or suggested by anyone over more than a decade. The same data of DAMA/LIBRA--phase1 have also been analyzed searching for possible DM second-order diurnal effect; at present, the DM diurnal modulation amplitude -- expected because of the Earth diurnal motion -- evaluated on the basis of the DAMA Dark Matter annual modulation results is below the reached experimental sensitivity. Some of the perspectives of the presently running DAMA/LIBRA--phase2 are outlined. [ABSTRACT FROM AUTHOR]

The results obtained with the total exposure of 1.04 ton x yr col lected by DAMA/LIBRA--phase1 deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. during 7 annual cycles are briefly summarized. The DAMA/LIBRA--phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton x yr, corresponding to 14 annual cycles) give evidence at 9.3 σ C.L. for the presence of Dark Matter (DM) particles in the galactic halo, on the basis of the exploited model inde- pendent DM annual modulation signature by using highly radio-pure NaI(Tl) target. The modulation parameters are well in agreement with those expected for DM particles. No systematic or side reaction able to mimic the exploited DM signature has been found or suggested by anyone over more than a decade. Some of the perspectives of the presently running DAMA/LIBRA--phase2 are outlined. [ABSTRACT FROM AUTHOR]

The DAMA/LIBRA experiment, running at the Gran Sasso National Laboratory of the I.N.F.N. in Italy, has a sensitive mass of about 250 kg highly radiopure NaI(Tl). It is mainly devoted to the investigation of Dark Matter (DM) particles in the Galactic halo by exploiting the model independent DM annual modulation signature. The present DAMA/LIBRA experiment and the former DAMA/NaI one (the first generation experiment having an exposed mass of about 100 kg) have released so far results corresponding to a total exposure of 1.17 ton x yr over 13 annual cycles. They provide a model independent evidence of the presence of DM particles in the galactic halo at 8.9 σ C.L. on the basis of the investigated DM signature. The data of another annual cycle in the same DAMA/LIBRA running conditions are at hand. After the replacement at the end of 2012 of all the photomultipliers (PMTs) with new ones, having higher quantum efficiency, DAMA/LIBRA has entered to its phase 2; such a replacements allowed the lowering of the software energy threshold of the experiment in the present data taking. A short summary of the obtained results is presented and future perspectives of the experiment mentioned. [ABSTRACT FROM AUTHOR]