Collider Constraints and Prospects of a Scalar Singlet Extension to Higgs Portal Dark Matter

TL;DR

This paper explores a scalar singlet extension of the Higgs sector, analyzing collider constraints, potential signals at future colliders, and implications for dark matter models with a focus on Higgs precision measurements.

Contribution

It provides a comprehensive analysis of collider constraints and prospects for a scalar singlet Higgs extension, including dark matter interactions and future collider signatures.

Findings

Current Higgs data constrains the scalar singlet model

Potential signatures at linear colliders include modified Higgs couplings

The model can evade detection with specific parameter choices

Abstract

This work considers an extension of the Standard Model (SM) Higgs sector by a real, scalar singlet field, including applicability to a dark matter (DM) model with the addition of a Yukawa coupling to a Dirac fermion. The collider signatures and constraints on the mixed two-Higgs scenario are determined, including limits from Higgs production signals and exclusion searches, as well as constraints arising from the Higgs total and invisible widths. As there is overwhelming Higgs data which is consistent with a SM scenario, the case in which an additional scalar has evaded detection is further explored in the context of Higgs precision measurement. The discovery reach and prospective signatures of the model at a proposed linear collider are investigated, with particular focus on the Higgs triple coupling, and di-Higgs production processes.