Physics results from the first COHERENT observation of coherent elastic neutrino-nucleus scattering in argon and their combination with cesium-iodide data

Abstract

We present the results on the radius of the neutron distribution in 40 Ar, on the low-energy value of the weak mixing angle, and on the electromagnetic properties of neutrinos obtained from the analysis of the coherent neutrino-nucleus elastic scattering data in argon recently published by the COHERENT Collaboration, taking into account proper radiative corrections. We present also the results of the combined analysis of the COHERENT argon and cesium-iodide data for the determination of the low-energy value of the weak mixing angle and the electromagnetic properties of neutrinos. In particular, the COHERENT argon data allow us to improve significantly the only existing laboratory bounds on the electric charge q μμ of the muon neutrino and on the transition electric charge q μτ .

Constraints on light vector mediators through coherent elastic neutrino nucleus scattering data from COHERENT

“…We follow closely the same formalism developed in ref. [18] to analyse CEνNS Ar data and in ref. [16] for CsI data from the COHERENT Collaboration, to which the reader is referred for the details.…”

“…With the recent detection of CEνNS in a single-phase 24 kg liquid-argon scintillation detector [17] the COHERENT Collaboration has started to probe the CEνNS cross-section dependence on the square of the number of neutrons, N 2 , and unrevealed a new way to test the standard model (SM). Indeed, this new measurement allowed to gain additional and complementary information to that provided by the CsI dataset on nuclear physics, neutrino properties, physics beyond the SM, and electroweak interactions [18].…”

Determining the nuclear neutron distribution from Coherent Elastic neutrino-Nucleus Scattering: current results and future prospects

“…Nevertheless, given the low momentum transfers involved in CEνNS, it is enough to characterize the structure factors using the first moment of the distribution in Q 2 . For the nuclear structure factors F M i (where i = p, n) this corresponds to the so-called point-proton and point-neutron distribution radii 1 [40,70,71,78] (…”

“…A non-exhaustive list of BSM topics covered includes bounds on non-standard neutrino interactions (NSI) [5][6][7][8][9][10][11][12][13][14][15][16][17][18], constraints on JHEP08(2020)030 neutrino electromagnetic properties [19][20][21][22][23], sterile neutrino searches [24,25], or searches for new weakly-interacting particles from a hidden sector [26][27][28]. On the other hand, standard physics studies include new constraints on the weak mixing angle [29][30][31] at very low momentum transfer, as well as studies of the nuclear structure factors of the target nuclei [32][33][34][35][36][37][38][39][40][41].…”

“…Notice that point-proton and point-neutron radii are usually labeled in the literature Rp,n. In here to avoid confusion with the notation of ref [40]. we explicitly keep the index pt when referring to the point-nucleon distribution radii.…”