D. Prosperi

Search for WIMP annual modulation signature: Results from DAMA/NaI-3 and DAMA/NaI-4 and the global combined analysis

Data, collected by the similar or equal to 100 kg NaI(TI) DAMA set-up at the Gran Sasso National Laboratory of I.N.F.N. during two further yearly cycles (DAMA/NaI-3 and DAMA/NaI-4; statistics of 38475 kg (.) day), have been analysed in terms of WIMP annual modulation signature. The results agree with those previously achieved. The cumulative analysis of all the available data (DAMA/NaI-1 to 4; statistics of 57986 kg(.)day) favours the possible presence of a WIMP with M-W = (52(-8)(+10)) GeV and xi sigma(p) = (7.2(-0.9)(+0.4)) (.) 10(-6) pb at 4 sigma C.L., when standard astrophysical assumptions are considered. The allowed mass extends up to 105 GeV (1 sigma) when the uncertainty on the mean value of the local velocity v(0) is taken into account and up to 132 GeV(1 a) in case a possible bulk halo rotation is taken into account. Moreover, the allowed regions extend to lower xi sigma(p) values when the upper limits on the recoil differential counting rate obtained from DAMA/NaI-0 is included in the cumulative analysis (favouring, in case of standard assumptions, M-w = (44(-9)(+12)) GeV and xi sigma(p) = (5.4 +/- 1.0) (.)10(-6) pb at similar or equal to 4 sigma C.L.). The 3 sigma C.L. allowed regions in the xi sigma(p), M-w plane summarize the obtained main physical results

New limits on WIMP search with large-mass low-radioactivity NaI(Tl) set-up at Gran Sasso

Improved limits on WIMP search have been obtained by the pulse shape analysis of the data collected with a large-mass low-radioactivity NaI(Tl) set-up at Gran Sasso National Laboratory.

The DAMA/LIBRA apparatus

The similar or equal to 250 kg highly radiopure NaI(Tl) DAMA/LIBRA apparatus, running at the Gran Sasso National Laboratory (LNGS) of the INFN, is described

Searching for WIMPs by the annual modulation signature

Abstract A set of preliminary test data, collected with large mass highly radiopure NaI(Tl) detectors, has been analysed by a maximum likelihood method to search for the WIMP annual modulation signature.

On a further search for a yearly modulation of the rate in particle Dark Matter direct search

The results achieved with a statistics of 14962 kg . day, collected with the large mass highly radiopure DAMA NaI(TI) set-up, are described and investigated in terms of WIMP annual modulation signature. A maximum likelihood analysis of these data, combined with the statistics of 4549 kg day previously published (total statistics of 19511 kg . day), favours the hypothesis of presence of an annual modulation at 99.6% C.L

Dark matter particles in the Galactic halo: Results and implications from DAMA/NaI

The DAMA/NaI experiment (≃100 kg highly radiopure NaI(Tl)) was proposed, designed and realized to effectively investigate in a model-independent way the presence of a Dark Matter particle component in the galactic halo by exploiting the annual modulation signature. With a total exposure of 107731 kg · day, collected over seven annual cycles deep underground at the Gran Sasso National Laboratory of the I.N.F.N., it has pointed out — at 6.3σC.L. — an effect which satisfies all the peculiarities of the signature and neither systematic effects nor side reactions able to mimic the signature were found. Moreover, several (but still few with respect to the possibilities) corollary model dependent quests for the candidate particle have been carried out. In this paper the obtained results are summarized and some perspectives are discussed at some extent.

Possible implications of the channeling effect in NaI(Tl) crystals

The channeling effect of low energy ions along the crystallographic axes and planes of NaI(Tl) crystals is discussed in the framework of corollary investigations on WIMP dark matter candidates. In fact, the modeling of this existing effect implies a more complex evaluation of the luminosity yield for low energy recoiling Na and I ions. In the present paper related phenomenological arguments are developed and possible implications are discussed at some extent.

Search for solar axions by Primakoff effect in NaI crystals

The results of a search for possible signal due to Primakoff coherent conversion of solar axions into photons in NaI(Tl) are presented. The experiment has been carried out at the Gran Sasso National Laboratory of INFN; the used statistics is 53437 kg day. The presently most stringent experimental limit on g(a gamma gamma) from this process is obtained: g(a gamma gamma) < 1.7 x 10(-9) GeV-1 (90% C.L.). In particular, the axion mass window m(a) greater than or similar to 0.03 eV, not accessible by other direct methods, is explored and KSVZ axions with mass larger than 4.6 eV are excluded at 90% C.L

Performances of the ≃ 100 kg NaI(Tl) set-up of the DAMA experiment at Gran Sasso

SummaryThe main features of the highly radiopure ≃ 100 kg NaI(Tl) set-up, searching for particle dark matter deep underground at the Gran Sasso National Laboratory of INFN, are described in some details.

New limits on particle dark matter search with a liquid Xenon target-scintillator

New results on WIMP-Xe-129 elastic scattering are presented. The target-detector is a pure liquid Xenon scintillator filled with Kr-free Xenon enriched in Xe-129 at 99.5%. Preliminary measurements with neutrons to estimate the quenching factor and to study a statistical pulse shape discrimination between electromagnetic background and recoils are also discussed