A recent experimental study of excited $^{8}\!Be$ decay to its ground state reveals an anomaly in the final states angle distribution. This exceptional result is attributed to a new vector gauge boson X(16.7). We study the significance of this new boson, especially its effect in anomalies observed in long-lasting experimental measurements. By comparing the discrepancies between the standard model predictions and the experimental results, we manage to find out the values and regions of the couplings of X(16.7) to muon and muon neutrino. In this work, we find that the newly observed boson X(16.7) may be the solution of both NuTeV anomaly and the $(g-2)_μ$ puzzle.
The NuTeV Anomaly, Lepton Universality, and Non-Universal Neutrino-Gauge Couplings
在以前的研究中，我们发现，具有中微子规范耦合的味普适抑制的模型与NuTeV和Z极数据兼容。在本文中，我们扩大我们的分析，以获得约束的味道依赖耦合抑制，包括轻子普适性数据W，τ，π和K衰变适合模型参数。我们发现，这些数据是一致的各种模式的耦合抑制。特别是，在这种情况下，产生的抑制轻中微子与重规范单重态（neutrissimos）的混合，我们发现模式的味道依赖的耦合抑制，这也是一致的约束从mu -> e γ。
The new measurement of the anomalous magnetic moment of muon at the Fermilab Muon $g-2$ experiment has strengthened the significance of the discrepancy between the standard model prediction and the experimental observation from the BNL measurement. If new physics responsible for the muon $g-2$ anomaly is supersymmetric, one should consider how to obtain light electroweakinos and sleptons in a systematic way. The gauge coupling unification allows a robust prediction of the gaugino masses, indicating that the electroweakinos can be much lighter than the gluino if anomaly-mediated supersymmetry b…
We explore a simple model containing two singlet scalars as dark matter supplemented with a vector-like lepton. Evading collider and dark matter constraints, the model is able to accommodate the correct dark matter relic abundance and the muon g-2 anomaly when the masses of the three new fields are around 100 GeV and the values of the minimum amount of required couplings are order one.
We investigate a two Higgs doublet model with extra flavour depending $U(1)_X$ gauge symmetry where $Z'$ boson interactions can explain the Atomki anomaly by choosing appropriate charge assignment for the SM fermions. For parameter region explaining the Atomki anomaly we obtain light scalar boson with $\mathcal{O}(10)$ GeV mass, and we explore scalar sector to search for allowed parameter space. We then discuss anomalous magnetic dipole moment of muon and lepton flavour violating processes induced by Yukawa couplings of our model.
In light of very recent E989 experimental result, we investigate the possibility that heavy sparticles explain the muon g-2 anomaly. We focus on the bino-smuon loop in an effective SUSY scenario, where a light gravitino plays the role of dark matter and other sparticles are heavy. Due to the enhancement of left-right mixing of smuons by heavy higgsinos, the contribution of bino-smuon loop can sizably increase the prediction of muon g-2 to the experimental value. Under collider and vacuum stability constraints, we find that TeV scale bino and smuon can still account for the new muon g-2 anomaly…
Motivated by the long-standing discrepancy between the Standard Model prediction and the experimental measurement of the muon magnetic dipole moment, we have recently proposed to interpret this muon $g-2$ anomaly in terms of the loop effect induced by a new massive spin-2 field $G$. In the present paper, we investigate the unitarity bounds on this scenario. We calculate the $s$-wave projected amplitudes for two-body elastic scatterings of charged leptons and photons mediated by $G$ at high energies for all possible initial and final helicity states. By imposing the condition of the perturbativ…
The prediction for the quartic coupling of the SM-like Higgs boson constrains the parameter space of SUSY models, even in scenarios where all of the new-particle masses are above the scale probed so far by the LHC. We study the implications of the Higgs-mass prediction on a recently-proposed SUSY model that features two pairs of Higgs doublets, and provides a solution to the g-2 anomaly thanks to a suitable enhancement of the muon Yukawa coupling.
Any observation of charged lepton flavor violation (CLFV) implies the existence of new physics beyond the SM in charged lepton sector. CLFV interactions may also contribute to the muon magnetic moment and explain the discrepancy between the SM prediction and the recent muon $g-2$ precision measurement at Fermilab. We consider the most general SM gauge invariant Lagrangian of $ΔL=0$ bileptons with CLFV couplings and investigate the interplay of low-energy precision experiments and colliders in light of the muon magnetic moment anomaly. We go beyond previous work by demonstrating the sensitivity…
Recently CDF II Collaboration reported that they measured W boson mass precisely. The measurement is deviated from the Standard Model (SM) Prediction at 7$σ$. Also, the recent FNAL measurement of the muon magnetic moment shows a $4.2σ$ deviation. To resolve the W boson as well as the muon $(g-2)$ anomalies, we explore the type-X two Higgs doublet model (2HDM). We analyze the $(m_A, \tanβ)$ parameter space of the type-X 2HDM consistent with the muon $(g-2)$, lepton universality test and recent $W$ boson mass measurments from the CDF II collaboration. We find that the measurement of the $h\to AA…
We examine the possibilities of accommodating the muon $g-2$ anomaly reported by Fermilab in the 2HDM with a discrete $Z_4$ symmetry in which an inert Higgs doublet field ($H,~A,~H^\pm$) has the lepton flavor violation $μ$-$τ$ interactions. We study the case of light $H$ (5 GeV $<m_H<$ 115 GeV) and assume the Yukawa matrices to be real and symmetrical. Considering relevant theoretical and experimental constraints, especially for the multi-lepton searches at the LHC, we find the muon $g-2$ anomaly can be explained within $2σ$ range in the region of 5 GeV $<m_H<20$ GeV, 130 GeV $< m_A~(m_{H^\pm}…
The muon $g-2$ anomaly was strengthened by recent experimental results at Fermilab, which may be signatures of new physics. A scenario of leptophilic scalar $ϕ_L$ accounting for the muon $g-2$ anomaly is investigated in this paper. Though a light $ϕ_L$ mainly decaying into standard model (SM) particles has been excluded by experiments, a dark leptophilic scalar $ϕ_L$ predominantly decaying into invisible fermionic dark matter (DM) $χ\barχ$ is still allowed. Considering the decay mode $ϕ_L \to χ\barχ$ opened (here $m_{ϕ_L} = 3 m_χ$), the coupling preferred by the muon $g-2$ and the $ϕ_L-χ$ coup…
We investigate the possibility to interpret the muon $g-2$ anomaly in terms of a massive spin-2 particle, $G$, which can be identified as the first Kaluza-Klein graviton in the generalized Randall-Sundrum model. In particular, we obtain the leading-order contributions to the muon $g-2$ by calculating the relevant one-loop Feynman diagrams induced by $G$. The analytic expression is shown to keep the gauge invariance of the quantum electrodynamics and to be consistent with the expected UV divergence structure. Moreover, we impose the theoretical bounds from the perturbativity and the experimenta…
We examine the charged boson and right-handed neutrino contribution to the muon g-2 anomaly in the twin Higgs models with the joint constraints of the Higgs global fit data, the precision electroweak data, the leptonic flavor changing decay μ\to eγ, and the mass requirement of the heavy gauge bosons. It comes out with the conclusion that some parameters such as the coupling of charged Higgs to the lepton y_μ, the top Yukawa y_t, and the heavy gauge boson coupling to the lepton V_μare constrained roughly in the range of 0.12\lesssim y_μ\lesssim 0.4, 0.4\lesssim y_t\lesssim 0.9, and 0.47\lesssim…
The present work introduces new scalar and fermionic degrees of freedom to the Standard Model. While the scalar sector is augmented by a complex scalar triplet and a doubly charged scalar singlet, the fermionic sector is extended by two copies of vector-like leptons. Of these, one copy is an $SU(2)_L$ singlet while the other, an $SU(2)_L$ doublet. We explain how this combination can offer a solution to the muon g-2 anomaly and also lead to non-zero neutrino masses. In addition, it is also shown that the parameter regions compliant with the two aforementioned issues can stabilise the electrowea…
