A joint explanation of W-mass and muon g-2 in 2HDM

TL;DR

This paper explores how a two-Higgs-doublet model with lepton flavor violation can simultaneously explain the W-mass anomaly and muon g-2 discrepancy, constraining Higgs mass splittings and parameter space.

Contribution

It provides a combined analysis of W-mass and muon g-2 anomalies within a 2HDM framework, considering experimental and theoretical constraints.

Findings

Mass splittings among Higgs bosons are tightly constrained.

Parameter space exists that explains both anomalies at 2σ level.

Favored Higgs masses are below 650 GeV for certain parameters.

Abstract

Since both $W$-mass and muon $g-2$ can be affected by the mass splittings among extra Higgs bosons $(H,~A,~H^\pm)$ in a 2HDM, we take a model with $\mu$-$\tau$ LFV interactions to examine the two anomalies reported respectively by CDF II and FNAL. We obtain the following observations: (i) Combined with theoretical constraints, the CDF $W$-mass measurement disfavors $H$ or $A$ to degenerate in mass with $H^\pm$, but allows $H$ and $A$ to degenerate. The mass splitting between $H^\pm$ and $H/A$ is required to be larger than 10 GeV. The $m_{H^\pm}$ and $m_{A}$ are favored to be smaller than 650 GeV for $m_H<120$ GeV, and allowed to have more large values with increasing of $m_H$. (ii) After imposing other relevant experimental constraints, there are parameter spaces that simultaneously satisfy (at $2\sigma$ level) the CDF $W$-mass, the FNAL muon $g-2$ and the data of lepton universality in $\tau$ decays, but the mass splittings among extra Higgs bosons are strictly constrained.