Novel Higgsino Dark Matter Signatures at the LHC

TL;DR

This paper proposes a new supersymmetric signal involving gluino decay chains leading to Higgsino dark matter, and develops a search strategy for detecting this at the high-luminosity LHC with promising discovery prospects.

Contribution

It introduces a novel gluino decay channel involving Higgsino dark matter and designs a search strategy for high-luminosity LHC runs.

Findings

Potential for discovery at 3000 fb$^{-1}$ luminosity.

Identification of main background processes.

Development of a targeted search strategy.

Abstract

In the LHC searches for gluinos it is usually assumed that they decay predominantly into the lightest neutralino plus jets. In this work we perform a proof-of-concept collider analysis of a novel supersymmetric signal in which gluinos decay mostly into jets and the bino-like neutralino ($\tilde\chi_3^0$), which in turn decays into the lightest Higgsino-like neutralino ($\tilde\chi_1^0$), considered the dark matter candidate, together with the SM-like Higgs boson ($h$). This new physics signal then consists of an LHC final state made up by four light jets, four $b$-jets, and a large amount of missing transverse energy. We identify $t \bar t$, $V$+jets ($V$= $W$, $Z$), and $t \bar t + X$ ($X$ = $W$, $Z$, $\gamma^*$, $h$) productions as the most problematic backgrounds, and develop a search strategy for the high luminosity phase of the LHC, reaching signal significances at the evidence level for a luminosity of 1000 fb$^{-1}$. The prospects for a luminosity of 3000 fb$^{-1}$ are even more promising, with discovery-level significances.