Neutron-gamma discrimination of CsI(Na) crystals for dark matter searches

Abstract

The luminescent properties of CsI(Na) crystals are studied in this report. By using a TDS3054C oscilloscope with a sampling frequency of 5 GS/s, we find out that nuclear recoil signals are dominated by very fast light pulse with a decay time of ~20 ns, while γ-ray signals have a decay time of ~600 ns. The wavelength of nuclear recoil and γ-ray signals are also different. The study of n/γ separation shows that the rejection factor can reach an order of 10-7 with signal efficiency more than 80% at an equivalent electron recoil energy of 20 keV or more. Such a property makes CsI(Na) an ideal candidate for dark matter searches.

arXiv comment11 pages, 15 figures

References in corpus (2)

• Supersymmetric Dark Matter
• Discriminating dark matter candidates using direct detection

Cited by in corpus (6)

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• Neutron Beam Tests of $CsI(Na)$ and $Ca{F}_2(Eu)$ Crystals for Dark Matter Direct Search
• The fast light of CsI(Na) crystals
• The low temperature performance of CsI(Na) crystals for WIPMs direct searches
• Characterization of SiPMs at 40 K for neutrino coherent detection based on pure CsI
• Evaluation of the neutron background in CsI target for WIMP direct detection when using a reactor neutrino detector as a neutron veto system