Non-standard Neutrino and $Z'$ Interactions at the FASER$\nu$ and the LHC

TL;DR

This paper investigates how a new gauge boson $Z'$ could influence neutrino interactions at FASER$ u$ and the LHC, providing new bounds on non-standard neutrino interactions through simulations and analysis of experimental data.

Contribution

It introduces a combined analysis of $Z'$ effects on neutrino interactions at FASER$ u$ and the LHC, offering improved constraints on non-standard neutrino interactions across different energy scales.

Findings

FASER$ u$ can probe $Z'$ couplings at medium energies.

LHC monojet data constrains $Z'$ at high energies.

Combined results enhance bounds on non-standard neutrino interactions.

Abstract

We study the impact of non-standard neutrino interactions in the context of a new gauge boson $Z'$ in neutral-current deep-inelastic scattering performed in ForwArd Search ExpeRiment-$\nu$ (FASER$\nu$) and in monojet production at the Large Hadron Collider (LHC). We simulate the neutral-current deep-inelastic neutrino-nucleon scattering $\nu N \rightarrow \nu N$ at FASER$\nu$ in the presence of an additional $Z'$ boson, and estimate the anticipated sensitivities to the gauge coupling in a wide range of $Z'$ mass. At the LHC, we study the effect of $Z'$ on monojet production, which can be enhanced in regions with large missing transverse momenta. We then use the recent results from ATLAS with an integrated luminosity of 139 fb$^{-1}$ to improve the limits on the gauge coupling of $Z'$. We interpret such limits on $Z'$ gauge couplings as bounds on effective non-standard neutrino interactions. We show that the FASER$\rm \nu$ and the LHC results cover the medium and high energy scales, respectively, and complement one another.