Neutrino, Electroweak and Nuclear Physics from COHERENT Elastic Neutrino-Nucleus Scattering with Refined Quenching Factor

M. Cadeddu, F. Dordei, C. Giunti, Y. F. Li, Y. Y. Zhang

Published 2019-08-16Version 1

We present an updated analysis of the coherent neutrino-nucleus elastic scattering data of the COHERENT experiment taking into account the refined quenching factor published recently in \url{arXiv:1907.04828}. Through a fit of the COHERENT time-integrated energy spectrum, we show that the new improved quenching factor leads to a better determination of the average rms radius of the neutron distributions of $^{133}\text{Cs}$ and $^{127}\text{I}$, while in combination with the atomic parity violation (APV) experimental results it allows to determine a data-driven APV measurement of the low-energy electroweak mixing angle in very good agreement with the Standard Model prediction. We also find a $3.7\sigma$ evidence of the suppression of coherence due to the nuclear structure. Neutrino properties are better constrained by considering the COHERENT time-dependent spectral data, that allow us to improve the bounds on the neutrino charge radii and magnetic moments. We also present for the first time constraints on the neutrino charges obtained with coherent neutrino-nucleus elastic scattering data. In particular, we obtain the first laboratory constraints on the diagonal charge of $\nu_{\mu}$ and the $\nu_{\mu}$-$\nu_{\tau}$ transition charge.