Missing Energy plus Jet in the SMEFT

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 |Δ s|=|Δ d|=1 and right-handed |Δ c|=|Δ u|=1 transitions these are the best available limits, also considering rare kaon and charm decays. We estimate improvements for the 3000 \;fb⁻¹ High Luminosity Large Hadron Collider.