Missing Energy plus Jet in the SMEFT

Abstract

We study the production of dineutrinos in proton-proton collisions, with large missing transverse energy and an energetic jet as the experimental signature. Recasting a search from the ATLAS collaboration we work out constraints on semileptonic four-fermion operators, gluon and electroweak dipole operators and $Z$-penguins in the SMEFT. All but the $Z$-penguin operators experience energy-enhancement. Constraints on gluon dipole operators are the strongest, probing new physics up to 14 TeV, and improve over existing ones from collider studies. Limits on FCNC four-fermion operators are competitive with Drell-Yan production of dileptons, and improve on those for tau final states. For left-handed $|\Delta s|=|\Delta d|=1$ and right-handed $|\Delta c|=|\Delta u|=1$ transitions these are the best available limits, also considering rare kaon and charm decays. We estimate improvements for the $3000 \;\mathrm{fb}^{-1}$ High Luminosity Large Hadron Collider.