Lowering threshold of NaI(Tl) scintillator to 0.7 keV in the COSINE-100 experiment

Abstract

COSINE-100 is a direct dark matter search experiment, with the primary goal of testing the annual modulation signal observed by DAMA/LIBRA, using the same target material, NaI(Tl). In previous analyses, we achieved the same 1 keV energy threshold used in the DAMA/LIBRA's analysis that reported an annual modulation signal with 11.6$\sigma$ significance. In this article, we report an improved analysis that lowered the threshold to 0.7 keV, thanks to the application of Multi-Layer Perception network and a new likelihood parameter with waveforms in the frequency domain. The lower threshold would enable a better comparison of COSINE-100 with new DAMA results with a 0.75 keV threshold and account for differences in quenching factors. Furthermore the lower threshold can enhance COSINE-100's sensitivity to sub-GeV dark matter searches.

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Cited by in corpus (4)

• Upgrading the COSINE-100 Experiment for Enhanced Sensitivity to Low-Mass Dark Matter Detection
• COSINE-100 Full Dataset Challenges the Annual Modulation Signal of DAMA/LIBRA
• The SABRE South Technical Design Report Executive Summary
• Constraints on sub-GeV dark matter scattering on electrons with COSINE-100