Non-Standard Neutrino Interactions at Colliders

TL;DR

This paper investigates non-standard neutrino interactions (NSI) using collider data, providing bounds from LEP2 and LHC, and exploring their implications for neutrino physics beyond the Standard Model.

Contribution

It introduces a collider-based approach to constrain dimension-eight NSI operators, complementing existing bounds and highlighting LHC sensitivity at 14 TeV.

Findings

LEP2 bounds on NSI coefficients are around 10^{-2} to 10^{-3}

LHC at 14 TeV can probe NSI coefficients down to approximately 3 x 10^{-3}

Collider data offers a new avenue to study NSI effects beyond traditional neutrino experiments.

Abstract

Many extensions of the Standard Model lead to non-standard neutrino interactions (NSI), which can affect the interpretation of current and future neutrino data. We explore an alternative approach to the study of these dimension eight four fermion interactions (of coefficient $4 \epsilon G_F/\sqrt{2}$), by bringing into play collider data. In models where coefficients of potential dimension six operators are suppressed by cancellations, LEP2 provides interesting bounds on NSI operators ($\epsilon \lsim 10^{-2} - 10^{-3}$). If NSI are contact interactions at LHC energies, they induce an effective interaction $\bar{q} q W^+W^- e_\a^+ e_\b^-$(according to the Equivalence Theorem), to which the LHC at 14 TeV and with 100 fb$^{-1}$ of data has excellent sensitivity ($\epsilon \gsim 3 \times 10^{-3}$).