DAMA/LIBRA-phase1 results and perspectives of the phase2

R Bernabei,A Incicchitti,R Cerulli,V Caracciolo,F Montecchia,F Cappella,P Belli,X D Sheng ,H He ,Alessandro Di Marco ,S D’angelo ,Xiaohua Ma ,C J Dai ,Ruiguang Wang ,A D’angelo ,H H Kuang ,Z.p Ye

doi:10.1051/epjconf/20159503001

Abstract

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 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.

Highlights

The DAMA/LIBRA experiment [1,2,3,4,5,6,7,8,9,10,11,12,13] is presently running in its phase2; as the former DAMA/NaI, it has the main aim to investigate the presence of Dark Matter (DM) particles in the galactic halo by exploiting the model independent DM annual modulation signature.As a consequence of the Earth’s revolution around the Sun, the Earth should be crossed by a larger flux of DM particles around 2 June and by a smaller one around 2 December
The same data of DAMA/LIBRA–phase1 have 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
The DAMA/LIBRA experiment [1,2,3,4,5,6,7,8,9,10,11,12,13] is presently running in its phase2; as the former DAMA/NaI, it has the main aim to investigate the presence of DM particles in the galactic halo by exploiting the model independent DM annual modulation signature

Summary

Introduction

The DAMA/LIBRA experiment [1,2,3,4,5,6,7,8,9,10,11,12,13] is presently running in its phase; as the former DAMA/NaI (see for example Ref. [8, 14, 15] and references therein), it has the main aim to investigate the presence of DM particles in the galactic halo by exploiting the model independent DM annual modulation signature. EPJ Web of Conferences modulation must only be found in a well-defined low energy range, where DM particle induced events can be present (4); it must apply only to those events in which just one detector of many “fires” (single-hit events), since the DM particle multi-interaction probability is negligible (5); the modulation amplitude in the region of maximal sensitivity must be 7% for usually adopted halo distributions (6), but it can be larger (even up to 30%) in case of some possible scenarios such as e.g. those in Ref. Those of the DAMA/NaI (0.29 ton × yr) are given in Ref. A similar peak is not present in the (6–14) keV energy interval

Normalized Power

The direct ν annual modulation of

Findings

Conclusions