General COHERENT Constraints on Neutrino Non-Standard Interactions

TL;DR

This paper systematically analyzes COHERENT data to constrain neutrino non-standard interactions, revealing weak constraints on all parameters but strong limits on specific combinations and excluding certain solar neutrino fit scenarios.

Contribution

It provides the first comprehensive analysis of all ten neutral-current NSI parameters using COHERENT data, including constraints on individual and combined parameters.

Findings

Weak constraints on individual NSI parameters due to cancellations.

Strong constraints on linear combinations of up and down quark NSI parameters.

Exclusion of the LMA-Dark solar neutrino fit at over 5 sigma.

Abstract

We present the results of a systematic study of the constraints on neutrino neutral-current non-standard interactions (NSI) that can be obtained from the analysis of the COHERENT spectral and temporal data. First, we consider the general case in which all the ten relevant neutral-current NSI parameters are considered as free. We show that they are very weakly constrained by the COHERENT data because of possible cancellations between the up and down quark contributions. However, the up-down average parameters are relatively well constrained and the strongest constraints are obtained for an appropriate linear combination of up and down NSI parameters. We also consider the case in which there are only NSI with either up or down quarks, and we show that the LMA-Dark fit of solar neutrino data is excluded at $5.6\sigma$ and $7.2\sigma$ respectively, for NSI with up and down quark. We finally present the tight constraints that can be obtained on each NSI parameter if it is the dominant one, assuming that the effects of the others are negligible.