Limitation of EFT for DM interactions at the LHC

TL;DR

This paper examines the limitations of using effective field theory to analyze dark matter interactions at the LHC, providing analytical and simulation-based assessments of its validity across different energies.

Contribution

It extends previous work by analyzing all relevant operators, deriving validity conditions analytically, and validating these through Monte Carlo simulations.

Findings

EFT bounds are weaker when validity conditions are enforced.

Analytical results for EFT validity at 8 TeV and 14 TeV.

Monte Carlo simulations support the analytical validity assessments.

Abstract

We generalize in several directions our recent analysis of the limitations to the use of the effective field theory approach to study dark matter at the LHC. Firstly, we study the full list of operators connecting fermion DM to quarks and gluons, corresponding to integrating out a heavy mediator in the $s$-channel; secondly, we provide analytical results for the validity of the EFT description for both $\sqrt{s}=8$ {\rm TeV} and $14$ {\rm TeV}; thirdly, we make use of a MonteCarlo event generator approach to assess the validity of our analytical conclusions. We apply our results to revisit the current collider bounds on the ultraviolet cut-off scale of the effective field theory and show that these bounds are weakened once the validity conditions of the effective field theory are imposed.