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Title: First Measurement of Coherent Elastic Neutrino-Nucleus Scattering on Argon
We report the first measurement of coherent elastic neutrino-nucleus scattering (CEvNS) on argon using a liquid argon detector at the Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer CEvNS over the background-only null hypothesis with greater than 3σ significance. The measured cross section, averaged over the incident neutrino flux, is (2.2±0.7)×10−39  cm2—consistent with the standard model prediction. The neutron-number dependence of this result, together with that from our previous measurement on CsI, confirms the existence of the CEvNS process and provides improved constraints on nonstandard neutrino interactions.
Authors:
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Award ID(s):
2013205
Publication Date:
NSF-PAR ID:
10348869
Journal Name:
Physical review letters
Volume:
126
ISSN:
0031-9007
Sponsoring Org:
National Science Foundation
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