Low-Mass Higgs Bosons in the NMSSM and Their LHC Implications

TL;DR

This paper explores the NMSSM Higgs sector, focusing on light Higgs states near the electroweak scale, their unique properties, and implications for LHC searches, especially when the CP-odd Higgs is relatively light.

Contribution

It identifies novel parameter regions with light Higgs bosons in the NMSSM, differing from the decoupling scenario, and analyzes their phenomenology and LHC detection prospects.

Findings

Light Higgs states can be near or below the electroweak scale.

SM-like Higgs decay modes and couplings can be significantly altered.

New Higgs bosons may produce distinctive signatures at the LHC.

Abstract

We study the Higgs sector of the Next to Minimal Supersymmetric Standard Model (NMSSM) in light of the discovery of the SM-like Higgs boson at the LHC. We perform a broad scan over the NMSSM parameter space and identify the regions that are consistent with current Higgs search results at colliders. In contrast to the commonly studied "decoupling" scenario in the literature where the Minimal Supersymmetric Standard Model CP-odd Higgs boson mass is large mA >> mZ, we pay particular attention to the light Higgs states in the case when mA <~ 2mZ . The Higgs bosons in the NMSSM, namely three CP-even states, two CP-odd states, and two charged Higgs states, could all be rather light, near or below the electroweak scale, although the singlet-like states can be heavier. The SM-like Higgs boson could be either the lightest CP-even scalar or the second lightest CP-even scalar, but is unlikely to be the heaviest scalar. These NMSSM parameter regions have unique properties and offer rich phenomenology. The decay branching fractions for the SM-like Higgs boson may be modified appreciably. The correlations of gamma gamma/V V and V V/b b can be substantially altered. The new Higgs bosons may be readily produced at the LHC and may decay to non-standard distinctive final states, most notably a pair of Higgs bosons when kinematically accessible. We evaluate the production and decay of the Higgs bosons and comment on further searches at the LHC to probe the Higgs sector of the NMSSM.