Exploring the Higgs sector of the MRSSM with a light scalar

TL;DR

This paper investigates a specific scenario within the MRSSM where the second-lightest Higgs boson aligns with the observed 125 GeV particle, highlighting implications for dark matter and collider searches.

Contribution

It introduces a novel scenario with a light singlet and bino-singlino in the MRSSM, showing how the second-lightest Higgs can match the observed Higgs mass with reduced loop corrections.

Findings

The second-lightest Higgs can be SM-like with mass near 125 GeV.

Light singlet and neutralino states are compatible with dark matter constraints.

Parameter regions are identified for future LHC and dark matter experiments.

Abstract

In a recent paper we showed that the Minimal R-symmetric Supersymmetric Standard Model (MRSSM) can accommodate the observed 125 GeV Higgs boson as the lightest scalar of the model in agreement with electroweak precision observables, in particular with the W boson mass and $T$ parameter. Here we explore a scenario with the light singlet (and bino-singlino) state in which the second-lightest scalar takes the role of the SM-like boson with mass close to 125 GeV. In such a case the second-lightest Higgs state gets pushed up via mixing already at tree-level and thereby reducing the required loop correction. Unlike in the NMSSM, the light singlet is necessarily connected with a light neutralino which naturally appears as a promising dark matter candidate. We show that dark matter and LHC searches place further bounds on this scenario and point out parameter regions, which are viable and of interest for LHC Run II and upcoming dark matter experiments.