Models with two Higgs doublets and a light pseudoscalar:a portal to dark matter and the possible $\mathbf{(g-2)_\mu}$ excess

TL;DR

This paper explores a two-Higgs doublet model with a light pseudoscalar and a fermionic dark matter candidate, demonstrating it can simultaneously explain the muon g-2 anomaly and dark matter relic abundance within experimental constraints.

Contribution

It introduces a specific two-Higgs doublet model with a light pseudoscalar and fermionic dark matter, showing it can address both muon g-2 and dark matter problems simultaneously.

Findings

The model can explain the muon g-2 discrepancy.

It accounts for dark matter relic density.

All experimental constraints are satisfied.

Abstract

In the context of a two-Higgs doublet model, supplemented by an additional light pseudoscalar Higgs boson and a stable isosinglet fermion, we consider the possibility of addressing simultaneously the discrepancy from the standard expectation of the anomalous magnetic moment of the muon recently measured at Fermilab and the longstanding problem of the dark matter in the universe which can be accounted for by a thermal weakly interacting massive particle. We show that it is indeed possible, for a range of masses and couplings of the new light pseudoscalar and the fermionic states, to explain at the same time the two features while satisfying all other constraints from astroparticle physics and collider searches, including the constraints from flavor physics.