Self-consistent Dark Matter Simplified Models with an s-channel scalar mediator

Abstract

We examine Simplified Models in which fermionic DM interacts with Standard Model (SM) fermions via the exchange of an $s$-channel scalar mediator. The single-mediator version of this model is not gauge invariant, and instead we must consider models with two scalar mediators which mix and interfere. The minimal gauge invariant scenario involves the mixing of a new singlet scalar with the Standard Model Higgs boson, and is tightly constrained. We construct two Higgs doublet model (2HDM) extensions of this scenario, where the singlet mixes with the 2nd Higgs doublet. Compared with the one doublet model, this provides greater freedom for the masses and mixing angle of the scalar mediators, and their coupling to SM fermions. We outline constraints on these models, and discuss Yukawa structures that allow enhanced couplings, yet keep potentially dangerous flavour violating process under control. We examine the direct detection phenomenology of these models, accounting for interference of the scalar mediators, and interference of different quarks in the nucleus. Regions of parameter space consistent with direct detection measurements are determined.

32 pages, 9 figures. References added and minor corrections made to match published version

References in corpus (15)

• Scalar Simplified Models for Dark Matter
• A Renormalizable Model for the Galactic Center Gamma Ray Excess from Dark Matter Annihilation
• Search for invisible decays of Higgs bosons in the vector boson fusion and associated ZH production modes
• Delta r and the W-boson mass in the Singlet Extension of the Standard Model
• Singlet fermionic dark matter
• Constraining Dark Sectors at Colliders: Beyond the Effective Theory Approach
• On the Validity of the Effective Field Theory for Dark Matter Searches at the LHC Part III: Analysis for the $t$-channel
• Blind Spots for neutralino Dark Matter in the MSSM with an intermediate m_A
• Gravitational waves at aLIGO and vacuum stability with a scalar singlet extension of the Standard Model
• Determining the CP nature of spin-0 mediators in associated production of dark matter and $t\bar{t}$ pairs
• Dark Forces in the Sky: Signals from Z' and the Dark Higgs
• Impact of Mass Generation for Simplified Dark Matter Models
• Flavour constraints on multi-Higgs-doublet models: Yukawa alignment
• Interference effects of two scalar boson propagators on the LHC search for the singlet fermion DM
• Solutions to the Renormalization Group Equations for Yukawa Matrices as an Answer to the Quark and Lepton Mass Problem

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• Dark Matter phenomenology : from simplified WIMP models to refined alternative solutions
• 2HDM singlet portal to dark matter
• Dark Matter Searches with Top Quarks