Neutrino, electroweak, and nuclear physics from COHERENT elastic neutrino-nucleus scattering with refined quenching factor

Abstract

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 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 Cs and 127 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 3.7σ 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 νµ and the νµ-ντ transition charge.

Recent Probes of Standard and Non-standard Neutrino Physics With Nuclei

“…An independent analysis combining APV and CEνNS data was perfomed in Ref. [106] leading to essentially similar results. Finally, it is worthwhile to mention the reported upper bound on the neutron skin ∆R np = ∆R n − ∆R p = 0.7 +0.9 −1.1 fm [32].…”

Coherent elastic neutrino-nucleus scattering at the European Spallation Source

“…In principle, adding the timing and energy information provided in Ref. [142] can help to tighten their constraints to some degree [15,21]; however, the final result is subject to uncertainties in the treatment of the background and systematic errors assumed. The different areas in the two panels in Fig.…”

“…Moreover in BSM models with neutrino masses, due to the mismatch between the mass and flavor bases, transition charge radii r 2 αβ may be generated for the flavor states. In the most general case where both diagonal and transition charge radii are considered, the effective weak coupling is modified as [21,150]:…”

“…However, reactor and solar experiments (among others) bound the ν e magnetic moments at the level of 10 −11 µ B [128,154] and render its effect well beyond the reach of any of the CEνNS experiments considered here. For this reason we only show on Table III our results on the sensitivity to µ νµ for which current scattering experiments yield a bound of 6.8×10 −10 at 90% CL [21] which, as seen in the table, can be improved with some of the considered setups.…”

Improved global fit to Non-Standard neutrino Interactions using COHERENT energy and timing data

“…More recently the COHERENT collaboration released the detailed timing and energy information [35] of their data. This allows for further tests of NP and it has been used to this effect in a series of recent works [36][37][38][39][40][41][42][43][44][45][46]. With this motivation, in this work we quantify the effect of including the timing and energy information of COHERENT data on the bounds on NC NSI, in particular in the combined global analysis from oscillation experiments.…”