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The first results obtained by the DAMA/LIBRA–phase2 experiment with the data collected deep underground at the Gran Sasso National Laboratory over 6 independent annual cycles (corresponding to a total exposure of 1.13 ton × yr) are presented. The DAMA/LIBRA–phase2 apparatus, about 250 kg highly radio-pure NaI(Tl), profits of a second generation high quantum efficiency photomultipliers and of new electronics; in the new configuration the software energy threshold is at 1 keV. The DAMA/LIBRA–phase2 data confirm the evidence of a signal that meets all the requirements of the model independent Dark Matter annual modulation signature, at 9.5 σC.L. in the energy region (1-6) keV. In the energy region between 2 and 6 keV, where data are also available from DAMA/NaI and DAMA/LIBRA–phase1 the achieved C.L. for the full exposure (2.46 ton × yr) is 12.9 σ.

The DAMA/LIBRA experiment, consisting of about 250 kg of highly radio-pure NaI(Tl) target, is running deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N.; its main aim is the investigation of Dark Matter (DM) particles in the Galactic halo by means of the model independent DM annual modulation signature. In this paper we briefly summarize the results obtained in its first phase of measurements (DAMA/LIBRA–phase1) lasted for 7 annual cycles with a total exposure of 1.04 ton×yr. The DAMA/LIBRA–phase1 and the former DAMA/NaI data (cumulative exposure 1.33 ton×yr, corresponding to 14 annual cycles) give evidence at 9.3 σC.L. for the presence of DM particles in the galactic halo. No systematic or side reaction able to mimic the exploited DM signature has been found or suggested by anyone over more than a decade. At fall 2010 a relevant upgrade of the experiment has been performed: all the PMTs have been replaced by new ones having higher quantum efficiency. After some optimization periods, a new phase of measurement, DAMA/LIBRA–phase2, has began in this new configuration with increased sensitivity. Some of the perspectives of the presently running DAMA/LIBRA–phase2 are mentioned.

The results obtained with the total exposure of 1.04 ton × 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 × yr, corresponding to 14 annual cycles) give evidence at 9.3 σC.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. The modulation amplitude of the single-hitevents in the (2–6) keV energy interval is: (0.0112±0.0012)cpd/kg/keV; the measured phase is (144±7)days and the measured period is (0.998±0.002)yr, values 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.

The present DAMA/LIBRA experiment and the former DAMA/NaI have cumulatively released so far the results obtained with the data collected over 13 annual cycles (total exposure: 1.17 ton per year). They give a model independent evidence of the presence of dark matter particles in the galactic halo on the basis of the dark matter annual modulation signature at 8.9 σ C.L. for the cumulative exposure. [ABSTRACT FROM AUTHOR]

As a result of about five years of new developments, the second-generation LIBRA (Large sodium Iodide Bulk for RAre processes) set-up of the DAMA experiment has been realized and installed in the Gran Sasso National Laboratory of the I.N.F.N.. It is made of ≃250 kg low-background NaI(Tl) detectors and has been operative since March 2003. It works as an observatory for rare processes and is mainly devoted to further investigation on the dark matter particle component in the galactic halo. New R&D efforts toward a possible NaI(Tl) ton set-up, which we proposed in 1996, have been funded and started in 2003. [Copyright &y& Elsevier]

The ≃ 100 kg highly radiopure NaI(Tl) set-up of the DAMA project (DAMA/NaI) has investigated the model- independent WIMP annual modulation signature over seven annual cycles for a total exposure of 107731 kg × day, obtaining a model-independent evidence for the presence of a dark matter particle component in the galactic halo at 6.3 σ C.L.. Some of the many possible corollary model-dependent quests for the candidate particle have been investigated with the total exposure as well. [Copyright &y& Elsevier]

DAMA experiment is an observatory for rare events mainly devoted to WIMP search at the Gran Sasso National Laboratory of the I.N.F.N.. In this paper, the most recent results obtained with the ⋍6.5 kg liquid Xenon set-up are briefly summarized. [Copyright &y& Elsevier]

The long-standing model-independent annual modulation effect measured by the DAMA Collaboration, which fulfills all the requirements of a dark matter annual modulation signature, and the new result by the CoGeNT experiment that shows a similar behavior are comparatively examined under the hypothesis of a dark matter candidate particle interacting with the detectors' nuclei by a coherent elastic process. The ensuing physical regions in the plane of the dark matter-particle mass versus the dark matter-particle nucleon cross-section are derived for various galactic halo models and by taking into account the impact of various experimental uncertainties. It is shown that the DAMA and the CoGeNT regions agree well between each other and are well fitted by a supersymmetric model with light neutralinos which satisfies all available experimental constraints, including the most recent results from CMS and ATLAS at the CERN Large Hadron Collider. [ABSTRACT FROM AUTHOR]

The DAMA/NaI experiment (≃ 100 kg highly radiopure NaI(Tl)) at the Gran Sasso National Laboratory of the I.N.F.N. had the unique feature to effectively investigate the presence of Dark Matter particle in the galactic halo by exploiting the model independent annual modulation signature. With a total exposure of more than 105 kg × day, collected over seven annual cycles, it has pointed out at 6.3 σ C.L. an effect which satisfies all the many peculiarities of the signature. Neither systematics nor side reactions able to account for the observed effect were found. No experiment whose result can be directly compared in a model independent way with the experimental one of DAMA/NaI is available so far. Several (but still few with respect to the possibilities) corollary model dependent quests for the candidate particle have also been carried out. At present the second generation DAMA/LIBRA set-up (≃ 250 kg highly radiopure NaI(Tl)) is in operation. Positive model dependent hints have also been pointed out by indirect searches for Dark Matter particles in space experiments and are not in contradiction with DAMA/NaI. Thus, the ongoing of model independent experiment deep underground and the new space experiments foreseen in incoming years will certainly further increase our knowledge of the field. [Copyright &y& Elsevier]

DAMA is searching for rare processes by developing and using several kinds of radiopure scintillators: in particular, NaI(TI), liquid Xenon and CaF2(Eu). Here only the results released so far on the WIMP annual modulation signature are shortly summarized. Next perspectives are briefly mentioned. [Copyright &y& Elsevier]

DAMA is searching for rare processes by developing and using several kinds of radiopure scintillators: in particular, NaI(Tl), liquid Xenon and CaF2(Eu). Here more recent results are summarized with particular attention to the investigation of the WIMP annual modulation signature. [Copyright &y& Elsevier]

The double-beta decay of 116Cd has been investigated with the help of radiopure enriched 116CdWO4 crystal scintillators (mass of 1.162 kg) at the Gran Sasso underground laboratory. The half-life of 116Cd relative to the 2ν2β decay to the ground state of 116Sn was measured with the highest up-to-date accuracy as T1/2=(2.63+0.11-0.12)×1019 yr. A new improved limit on the 0ν2β decay of 116Cd to the ground state of 116Sn was set as T1/2≥2.2×1023 yr at 90% C.L., which is the most stringent known restriction for this isotope. It corresponds to the effective Majorana neutrino mass limit in the range ⟨mν⟩≤(1.0-1.7) eV, depending on the nuclear matrix elements used in the estimations. New improved half-life limits for the 0ν2β decay with majoron(s) emission, Lorentz-violating 2ν2β decay, and 2β transitions to excited states of 116Sn were set at the level of T1/2≥1020-1022 yr. New limits for the hypothetical lepton-number violating parameters (right-handed currents admixtures in weak interaction, the effective majoron-neutrino coupling constants, R-parity violating parameter, Lorentz-violating parameter, heavy neutrino mass) were set. [ABSTRACT FROM AUTHOR]