Constraints on non-universal gaugino mass scenario using the latest LHC data

TL;DR

This paper analyzes the constraints on non-universal gaugino mass models within the MSSM using recent LHC data, focusing on Higgs mass compatibility, light higgsino states, and top squark and gluino exclusion limits.

Contribution

It provides updated exclusion limits on non-universal gaugino mass scenarios using the latest LHC search data, emphasizing the role of light higgsinos and specific decay channels.

Findings

Light higgsino-like neutralinos and charginos are nearly degenerate in mass.

Right-handed top squark tends to be lighter than other sfermions.

Gluino mass exclusion limits are derived from large missing energy and b-jet analyses.

Abstract

We investigate exclusion limits on the the non-universal gaugino mass scenario in the Minimal Supersymmetric Standard Model (MSSM), according the the latest results of the super-particle search at the LHC8 and the LHC13. In this scenario, suitable ratios of wino to gluino mass can realize the observed value of the Higgs boson mass, while keeping a small $\mu$ parameter. Such a small $\mu$ parameter corresponds to the mass of higgsino, so that lightest neutralino and chargino are higgsino-like and their masses are almost degenerate. Besides, we find that the right-handed top squark tends to be lighter than other sfermions and then the top squark search, where the top squark decays to a quark and higgsino, is relevant to our model. In our analysis, the exclusion limits are derived using the data of the top squark searches in the $bb + E_T^{\rm miss}$ and $tb + E_T^{\rm miss}$ channels. Furthermore, the exclusion limit on gluino mass, which is crucial to our scenario, is investigated as well. The analysis of the gluino is based on the data of the analysis with large missing energy and at least three b-tagged jets at the ATLAS experiment.