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Title: Calibration of the liquid argon ionization response to low energy electronic and nuclear recoils with DarkSide-50
DarkSide-50 has demonstrated the high potential of dual-phase liquid argon time projection chambers in exploring interactions of WIMPs in the GeV/c2 mass range. The technique, based on the detection of the ionization signal amplified via electroluminescence in the gas phase, allows to explore recoil energies down to the sub-keV range. We report here on the DarkSide-50 measurement of the ionization yield of electronic recoils down to about 180 eVer, exploiting 37Ar and 39Ar decays, and extrapolated to a few ionization electrons with the Thomas-Imel box model. Moreover, we present the determination of the ionization response to nuclear recoils down to ∼ 500 eVnr , the lowest ever achieved in liquid argon, using in situ neutron calibration sources and external datasets from neutron beam experiments.
Authors:
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Award ID(s):
1812492 1622345
Publication Date:
NSF-PAR ID:
10281343
Journal Name:
ArXivorg
Volume:
arXiv:2107.08087
ISSN:
2331-8422
Sponsoring Org:
National Science Foundation
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