Li-containing scintillating bolometers for low background physics

L Pattavina

doi:10.1051/epjconf/20136502003

Abstract

We present the performances of Li-based compounds used as scintillating bolometer for rare decay studies such as double-beta decay and direct dark matter investigations. The compounds are tested in a dilution refrigerator installed in the underground laboratory of Laboratori Nazionali del Gran Sasso (Italy). Low temperature scintillating properties are investigated by means of different radioactive sources, and the radio-purity level for internal contaminations are estimated for possible employment for next generation experiments.

Highlights

IntroductionLithium containing crystal scintillators (such as Li2MoO4, LiF and Li6Eu(BO3)3) can have important applications in applied physics (detection of neutron fluxes through n captures by 6Li) as well as in fundamental physics in the investigation of neutrinoless double-beta decay (DBD), dark matter (DM) and solar 7Li axions
Lithium containing crystal scintillators (such as Li2MoO4, LiF and Li6Eu(BO3)3) can have important applications in applied physics as well as in fundamental physics in the investigation of neutrinoless double-beta decay (DBD), dark matter (DM) and solar 7Li axions.Neutron induced nuclear recoils can mimic the WIMP signal in DM direct searches, so the evaluation and the minimization of the neutron background is mandatory in order to reach elusive rates in the detectors
Among the various techniques for the estimation of very low neutron backgrounds and their energy distributions the most promising one are based on neutron-induced nuclear reactions: the neutron energy is shared between the reaction products and the estimation of the deposited energy gives directly the measurement of the incident neutron energy. 6Li is a favorable isotope for this type of investigation due to its large absorption neutron crosssection in a wide energy range

Summary

Introduction

Lithium containing crystal scintillators (such as Li2MoO4, LiF and Li6Eu(BO3)3) can have important applications in applied physics (detection of neutron fluxes through n captures by 6Li) as well as in fundamental physics in the investigation of neutrinoless double-beta decay (DBD), dark matter (DM) and solar 7Li axions. Neutron induced nuclear recoils can mimic the WIMP signal in DM direct searches, so the evaluation and the minimization of the neutron background is mandatory in order to reach elusive rates in the detectors. It should be mentioned that Li-containing bolometer are interesting target for the investigation of Solar Axions. The material can be used as a target to search for hypothetical axions emitted in the solar core in deexcitation of the 478 keV level, which is being populated in one of branches of the pp chain. In this work we will discuss performances and feature of two Li-containing scintillating bolometer: Li2MoO4 and Li6Eu(BO3). The detector design is similar to the ones already presented in some works of our group [4][6][8]

Li2MoO4 scintillating bolometer

Conclusion