Dark Matter investigation by DAMA at Gran Sasso

Experimental observations and theoretical arguments at Galaxy and larger scales have suggested that a large fraction of the Universe is composed by Dark Matter particles. This has motivated the DAMA experimental efforts to investigate the presence of such particles in the galactic halo by exploiting a model independent signature and very highly radiopure set-ups deep underground. Few introductory arguments are summarized before presenting a review of the present model independent positive results obtained by the DAMA/NaI and DAMA/LIBRA set-ups at the Gran Sasso National Laboratory of the INFN. Implications and model dependent comparisons with other different kinds of results will be shortly addressed. Some arguments put forward in literature will be confuted.Comment: review article, 71 pages, 25 figures, 8 tables; v2: minor modifications. In publication on the International Journal of Modern Physics

No role for neutrons, muons and solar neutrinos in the DAMA annual modulation results

This paper summarizes in a simple and intuitive way why the neutrons, the muons and the solar neutrinos cannot give any significant contribution to the DAMA annual modulation results. A number of these elements have already been presented in individual papers; they are recalled here. Afterwards, few simple considerations are summarized which already demonstrate the incorrectness of the claim reported in PRL 113 (2014) 081302.Comment: 11 pages, 1 tabl

Investigating Earth shadowing effect with DAMA/LIBRA-phase1

In the present paper the results obtained in the investigation of possible diurnal effects for low-energy single-hit scintillation events of DAMA/LIBRA-phase1 (1.04 ton $\times$ yr exposure) have been analysed in terms of an effect expected in case of Dark Matter (DM) candidates inducing nuclear recoils and having high cross-section with ordinary matter, which implies low DM local density in order to fulfill the DAMA/LIBRA DM annual modulation results. This effect is due to the different Earth depths crossed by those DM candidates during the sidereal day.Comment: 22 pages, 9 figures, 1 table; in publication on Eur. Phys. J.

Final model independent result of DAMA/LIBRA-phase1

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 (i.e. adding a further 0.17 ton x yr exposure) are presented. The DAMA/LIBRA-phase1 data give evidence 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, at 7.5 sigma C.L.. Including also the first generation DAMA/NaI experiment (cumulative exposure 1.33 ton x yr, corresponding to 14 annual cycles), the C.L. is 9.3 sigma and the modulation amplitude of the single-hit events in the (2-6) keV energy interval is: (0.0112 \pm 0.0012) cpd/kg/keV; the measured phase is (144 \pm 7) days and the measured period is (0.998 \pm 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.Comment: 20 pages, 13 figures, 6 tables; in publication on Eur. Phys. J.

Model independent result on possible diurnal effect in DAMA/LIBRA-phase1

The results obtained in the search for possible diurnal effect in the single-hit low energy data collected by DAMA/LIBRA-phase1 (total exposure: 1.04 ton x yr) deep underground at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N. are presented. At the present level of sensitivity the presence of any significant diurnal variation and of diurnal time structures in the data can be excluded for both the cases of solar and sidereal time. In particular, the diurnal modulation amplitude expected, because of the Earth diurnal motion, on the basis of the DAMA Dark Matter annual modulation results is below the present sensitivity.Comment: 14 pages, 5 figures, 2 tables; in publication on Eur. Phys. J.

DAMA/LIBRA results and perspectives

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 yr over 13 annual cycles. They provide a model independent evidence of the presence of DM particles in the galactic halo at 8.9 sigma C.L.. A short summary of the obtained results is presented and future perspectives of the experiment mentioned.Comment: 12 pages, Proceed. of the 15th Bled Workshop "What Comes Beyond Standard Models" (December 2012), Vol. 13, No.

A few final comments to arXiv:1210.7548[hep-ph]

A few final comments on arXiv:1210.7548 are given to confute incorrect arguments claimed there

No role for muons in the DAMA annual modulation results

This paper gathers arguments and reasons why muons surviving the Gran Sasso mountain cannot mimic the Dark Matter annual modulation signature exploited by the DAMA/NaI and DAMA/LIBRA experiments. A number of these items have already been presented in individual papers. Further arguments have been addressed here in order to present a comprehensive collection and to enable a wider community to correctly approach this point.Comment: 26 pages, 9 figures. Few arguments added; version accepted for publication on Eur. Phys. J.

Particle Dark Matter and DAMA/LIBRA

The DAMA/LIBRA set-up (about 250 kg highly radiopure NaI(Tl) sensitive mass) is running at the Gran Sasso National Laboratory of the I.N.F.N.. The first DAMA/LIBRA results confirm the evidence for the presence of a Dark Matter particle component in the galactic halo, as pointed out by the former DAMA/NaI set-up; cumulatively the data support such evidence at 8.2 sigma C.L. and satisfy all the many peculiarities of the Dark Matter annual modulation signature. The main aspects and prospects of this model independent experimental approach will be outlined.Comment: Contributed paper to the Int. Conf. SciNeGHE 2009, Assisi, Italy, October 200