Muon $$g-2$$ anomaly and $$\mu $$–$$\tau $$-philic Higgs doublet with a light CP-even component

Abstract

We examine the possibilities of accommodating the muon $$g-2$$ g - 2 anomaly released by Fermilab in the 2HDM with a discrete $$Z_4$$ Z 4 symmetry in which an inert Higgs doublet field ($$H,~A,~H^\pm $$ H , A , H ± ) has the lepton flavor violation $$\mu $$ μ –$$\tau $$ τ interactions. We assume the Yukawa matrices to be real and symmetrical and investigate the case of light H (5 GeV $$<m_H<$$ < m H < 115 GeV). After imposing relevant theoretical and experimental constraints, especially for the multi-lepton searches at the LHC, we find that the muon $$g-2$$ g - 2 anomaly can be explained within $$2\sigma $$ 2 σ confidence level in the region of 5 GeV $$<m_H<20$$ < m H < 20 GeV, 130 GeV $$< m_A~(m_{H^\pm })<$$ < m A ( m H ± ) < 610 GeV, and 0.005 $$<\rho<$$ < ρ < 0.014. Meanwhile, the $$\chi ^2_\tau $$ χ τ 2 fitting the data of lepton flavour universality in the $$\tau $$ τ decays approaches to the SM prediction.

Scalar Dark Matter with a $μτ$ Flavored Mediator

“…Then, they point out that the LHC Run2 data will exclude 200 GeV ≤ m η 500 GeV [30,37]. They also explore the light mass region and show that m ρ < 20 GeV and 130 GeV < m η (m φ ± ) < 610 GeV are allowed [39]. These bounds are qualitatively the same in our case, but cannot be applied directly because of the different mass spectrum considered.…”

“…Collider searches for the heavy neutral scalars with the µτ interactions have been studied in Refs. [30,[37][38][39]. The signal processes are the electroweak production of the scalars such as pp → W ± * → φ ± ρ, φ ± η and pp → Z * → ρη followed by φ ± → τ ± ν µ , µ ± ν τ and ρ, η → τ ± µ ∓ .…”

Electron and muon magnetic moments and implications for dark matter and model characterisation in non-universal $U(1)^\prime$ supersymmetric models

“…When the BSM models are built in a flavor blind fashion, their g − 2 predictions for the electron and muon are correlated by ∆a e /∆a µ = m 2 e /m 2 µ . The SM prediction calculated up to ten loops within QED [13][14][15][16] yields a SM e = 1.159652181643 (25) (23) (16)(763)× 10 −3 , which is, in contrast to the muon g − 2 prediction, greater than the experimental results for the electron g − 2, ∆a e = −(8.8 ± 3.6) × 10 −13 .…”

Joint explanation of W-mass and muon g–2 in the 2HDM*

“…In our analysis, we extensively examine the parameter space of this model by considering various relevant theoretical and experimental constraints. For the single explanation of muon using the Higgs doublet field with μ-τ LFV interactions, see, for example, [44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61][62].…”

“…In the model, the fields H, A, and have no couplings to quarks; therefore, they are produced at the LHC mainly via electroweak processes, , , and . The final state signal mainly includes multi-leptons, and therefore multilepton event searches at the LHC can impose stringent constraints that require to be larger than 560 GeV [55]. Moreover, a very light H may escape the constraints of direct searches at the LHC [56].…”