New signatures and limits on R-parity violation from resonant squark production

TL;DR

This paper explores resonant squark production via R-parity violation at the LHC, proposing new signatures and setting limits on couplings, with implications for natural SUSY and future searches.

Contribution

It introduces new signatures for R-parity violating squark production and provides the first limits on these couplings using LHC data, especially for light stops.

Findings

Resonant squark production cross sections can surpass pair-production.

Current LHC searches exclude stops around 500-700 GeV.

Multi-TeV couplings involving stops are also constrained.

Abstract

We discuss resonant squark production at the LHC via baryonic $R$-parity violating interactions. The cross section easily exceeds pair-production and a new set of signatures can be used to probe squarks, particularly stops. These include dijet resonances, same-sign top quarks and four-jet resonances with large $b$-jet multiplicities, as well as the possibility of displaced neutralino decays. We use publicly available searches at $\sqrt{s}=8$ TeV and first results from collisions at $\sqrt{s}=13$ TeV to set upper limits on $R$-parity violating couplings, with particular focus on simplified models with light stops and neutralinos. The exclusion reach of these signatures is comparable to $R$-parity-conserving searches, $m_{\tilde t}\simeq 500-700$ GeV. In addition, we find that O(1) couplings involving the stop can be excluded well into the multi-TeV range, and stress that new searches for single- and pair-produced four-jet resonances will be necessary to exclude sub-TeV stops for a natural SUSY spectrum with light higgsinos.