A Plan to Rule out Large Non-Standard Neutrino Interactions After COHERENT Data

TL;DR

This paper examines how recent COHERENT data constrains models with large non-standard neutrino interactions, especially those involving a new light gauge boson, and discusses future experimental prospects.

Contribution

It analyzes the impact of COHERENT results on models with large NSI mediated by a light gauge boson and forecasts future detection potential.

Findings

COHERENT data constrains certain large NSI models

Future experiments like CONUS can further test these models

COHERENT limits on lepton flavor violating NSI are derived

Abstract

In the presence of neutrino Non-Standard Interactions (NSI) with matter, the derivation of neutrino parameters from oscillation data must be reconsidered. In particular, along with the standard solution to neutrino oscillation, another solution known as "LMA--Dark" is compatible with global oscillation data and requires both $\theta_{12}>\pi/4$ and a certain flavor pattern of NSI with an effective coupling comparable to $G_F$. Contrary to conventional expectations, there is a class of models based on a new $U(1)_X$ gauge symmetry with a gauge boson of mass of few MeV to few 10 MeV that can viably give rise to such large NSI. These models can in principle be tested by Coherent Elastic $\nu$-Nucleus Scattering (CE$\nu$NS) experiments such as COHERENT and the upcoming reactor neutrino experiment, CONUS. We analyze how the recent results from the COHERENT experiment constrain these models and forecast the discovery potential with future measurements from COHERENT and CONUS. We also derive the constraints from COHERENT on lepton flavor violating NSI.