Latest Results and Status of CEvNS on LAr from the COHERENT Collaboration

Coherent Elastic Neutrino-Nucleus Scattering(CEvNS), first observed by the COHERENT Collaboration in 2017, is a neutral-current neutrino process. For neutrino energies below 100MeV, it is the dominant cross-section. A precise measurement of the CEvNS cross-section will test new physics including constraints on nonstandard neutrino-quark interactions, the weak nuclear radius, and the particle nature of dark matter. In addition, development of CEvNS-sensitive technologies is useful for low-threshold WIMP dark matter searches and for sterile neutrino searches.

In order to obtain a precision measurement of the CEvNS cross-section, the COHERENT Collaboration has deployed a number of detectors with a range of target nuclei to the Spallation Neutron Source at Oak Ridge National Laboratory(ORNL). These include a single-phase liquid argon detector, COH-Ar-10. The 24kg fiducial-volume target, deployed to the SNS in Fall 2016, made the first low-N measurement of CEvNS in Spring 2020. This result confirmed the existence of the CEvNS process hypothesis and agreed with the Standard Model hypothesis to within 1σ. Here we detail that result, discuss improvements for an ongoing analysis, and expected results in further running.