# Search for dark matter produced with an energetic jet or a hadronically decaying W or Z boson at sqrt(s) = 13 TeV

## TL;DR

This paper reports a search for dark matter produced with energetic jets or hadronically decaying W/Z bosons at 13 TeV, setting new constraints on dark matter models and mediators, and comparing results with direct and indirect detection experiments.

## Contribution

First search to analyze dark matter production with jets or W/Z decays at 13 TeV, providing the strongest collider constraints on certain dark matter models.

## Key findings

- Excluded vector/axial-vector mediators up to 1.95 TeV.
- Set limits on scalar/pseudoscalar mediators up to 430 GeV.
- Provided the strongest collider constraints on dark matter production.

## Abstract

A search for dark matter particles is performed using events with large missing transverse momentum, at least one energetic jet, and no leptons, in proton-proton collisions at sqrt(s) = 13 TeV collected with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 12.9 inverse femtobarns. The search includes events with jets from the hadronic decays of a W or Z boson. The data are found to be in agreement with the predicted background contributions from standard model processes. The results are presented in terms of simplified models in which dark matter particles are produced through interactions involving a vector, axial-vector, scalar, or pseudoscalar mediator. Vector and axial-vector mediator particles with masses up to 1.95 TeV, and scalar and pseudoscalar mediator particles with masses up to 100 and 430 GeV respectively, are excluded at 95% confidence level. The results are also interpreted in terms of the invisible decays of the Higgs boson, yielding an observed (expected) 95% confidence level upper limit of 0.44 (0.56) on the corresponding branching fraction. The results of this search provide the strongest constraints on the dark matter pair production cross section through vector and axial-vector mediators at a particle collider. When compared to the direct detection experiments, the limits obtained from this search provide stronger constraints for dark matter masses less than 5, 9, and 550 GeV, assuming vector, scalar, and axial-vector mediators, respectively. The search yields stronger constraints for dark matter masses less than 200 GeV, assuming a pseudoscalar mediator, when compared to the indirect detection results from Fermi-LAT.