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

Abstract

Abstract. 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. PACS. 95.35.+d

Dark Matter Annual Modulation Results by DAMA/LIBRA

“…the SagDEG stream [7] and the caustics [43]. The 2σ contours in the plane (S m , Z m ) for the (2-6) keV and (6)(7)(8)(9)(10)(11)(12)(13)(14) keV energy intervals and those in the plane (Y m , t * ) are reported in Fig. 4 [18].…”

“…in refs. [4][5][6][7][8][9][10][11]. On the other hand, one should stress that it does not exist any approach in direct and indirect DM searches which can offer information on the nature of the candidate in a model independent way, that is without assuming any astrophysical, nuclear and particle Physics scenarios.…”

“…3. It can be inferred that a positive signal is present in the (2-6) keV energy interval, while S m values compatible with zero are present just above; in particular, the S m values in the (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) keV energy interval have random fluctuations around zero with χ 2 equal to 27.5 for 28 degrees of freedom. It has been also verified that the measured modulation amplitudes are statistically well distributed in all the crystals, in all the annual cycles and energy bins; these and other discussions can be found in ref.…”

“…It is based on the development and use of low background scintillators. The main experimental set-ups are: i) DAMA/NaI ( 100 kg of highly radiopure NaI(Tl)) that took data for 7 annual cycles and completed its data taking on July 2002 [1][2][3][4][5][6][7][8][9][10][11][12]; ii) DAMA/LXe, 6.5 kg liquid Kr-free Xenon enriched either in 129 Xe or in 136 Xe [13]; iii) DAMA/R&D, a facility dedicated to tests on prototypes and to perform experiments developing and using various kinds of low background crystal scintillators to investigate various rare processes [14]; iv) DAMA/Ge, where a e-mail: pierluigi.belli@roma2.infn.it DOI: 10.1051/ C Owned by the authors, published by EDP Sciences, 2014 , / sample measurements are carried out and where dedicated measurements on rare events are performed [15]; v) the second generation DAMA/LIBRA set-up, 250 kg highly radiopure NaI(Tl)) [16][17][18][19][20] mainly devoted to the investigation of the presence of Dark Matter (DM) particles in the Galactic halo. Profiting of the low background features of these set-ups, many rare processes have been studied.…”

New results and perspectives of DAMA/LIBRA

“…The presently running DAMA/LIBRA [1][2][3][4][5][6][7][8][9][10][11] experiment, as the former DAMA/NaI [12][13][14][15][16][17][18][19][20][21][22][23][24][25], has the main aim to investigate the presence of DM particles in the galactic halo by exploiting the model independent DM annual modulation signature (originally suggested in Ref. [26]).…”