125 GeV Higgs decay with lepton flavor violation in the μνSSM

Recently,the CMS and ATLAS collaborations have reported direct searches for the 125 GeV Higgs decay with lepton flavor violation,h→μτ.In this work,we analyze the signal of the lepton flavour violating（LFV） Higgs decay h→μτ in the μ.from γ Supersyninietric Standard Model（μνSSM） with slepton flavor mixing.Simultaneously,we consider the constraints from the LFV decay τ→μγ,the muon anomalous magnetic dipole moment and the lightest Higgs mass around 125 GeV.

Lepton flavor violating decays of vector mesons in the MRSSM

In this study,we analyze the rare decays of the neutral vector mesons J/ψ and Υ(nS)in the scenario of the minimal R-symmetric supersymmetric standard model using the effective Lagrangian method.The predicted branching ratios are dominated by the mass insertion parameters δ^(ij),i.e.,the off-diagonal inputs,and the contributions of different parts are comparable.Taking into account the experimental constraints on the mass insertion parameters,the predicted branching ratios for the most promising processes Υ(nS)→lτ are ten orders of magnitude smaller than the present experimental bounds.

The Lepton Flavor Violating Decays of AHin the Littlest Higgs Model with T-Parity Violation

The T-parity in the littlest Higgs model can be broken by the anomalous Wess-Zumin-Witten term, which leads that the lightest T-odd gauge boson AH decays into the SM particles. First, we examine some lepton flavor violating decays of AH, namely AH → τ±μ±, AH→ τ±e±, and AH→ τ±e±. We find that the branching ratios can reach 10-7 for AH → τ±μ±, 10-s for AH → τ±μ±, and 10-s for AH → τ±e± Then, we study the lepton flavor violating plus jets signatures of the heavy charged gauge boson and mirror quarks at the LHC, and find that it is possible to be detected for pp jets, and hardly to be detected for pp → τ±e± （μ±e±） ＋ 4 jets and p p → W H W H → τ±μ±（ τ±e±,μ±e±） ＋ 6 jets.

Phenomenology of Friedberg-Lee Texture in Left-Right Symmetric Model

We consider that the Higgs triplet Yukawa coupling takes the Friedberg-Lee texture, and the Higgs doublet Yukawa coupling simply identifies with the diagonal Yutawa coupling of charged lepton in the context of left-right symmetric model. In this scenario, the phenomenology, including effective neutrino masses, mixings, and thermal flavor-dependent leptogenesis and lepton flavor violation decays are studied. We investigate the combined constrain of the parameters in this scenario and test its consistency with present data.

Calculation of Decay μ→eγ in R_ζ Gauge in a Model of Electroweak-Scale Right-Handed Neutrinos

The lepton flavor violating process μ - eγ has been previously studied in a model of electroweak-scale right-handed neutrinos. In that work the decay amplitude was computed in unitarity gauge, augmented by some technical considerations that correct the leading term thus obtained. This complication arises because the mixing matrices appearing in the weak charged currents are not unitary in the model. In this paper, we recalculate the amplitude in Re gauge. The cancellation of the ξ dependence in the final result serves as a useful check to both the obtained amplitude and the technical points made in the previous work.

Neutrino masses and lepton-flavor-violating τ decays in the supersymmetric left-right model

In the supersymmetric left-right model, the light neutrino masses are given by the Type-seesaw mechanism. A duality property of this mechanism indicates that there exist eight possible Higgs triplet Yukawa couplings which result in the same neutrino mass matrix. In this paper, we work out the one-loop renormalization group equations for the effective neutrino mass matrix in the supersymmetric left-right model. The stability of the Typeseesaw scenario is briefly discussed. We also study the lepton-flavor-violating processes （τ → μγ and τ → eγ） by using the reconstructed Higgs triplet Yukawa couplings.

Probing Topcolor-Assisted Technicolor Models from Like-Sign Γ Pair Production in rγ Collisions

We consider the contributions of the extra gauge boson Z＇ to the like sign ^- production processes e-＇γ→e＋（μ＋）τ-τ-, induced by the tree-level flavor changing interactions. Since these rare production are far below the observable level in the Standard Model and other popular new physics models such as the minimal supersymmetric model, we find that, in the topcolor-assisted technicolor models, the Z＇ can give significant contributions to these processes, and with reasonable values of the parameters, the cross section cr can reach several tens of tb and may be detected at the eγ collisions.

Mini-review of rare charmonium decays at BESⅢ

Recently, the LHCb experiment announced 3.5σ evidence for direct CP violation in D0 decay by looking at the difference between A CP （D0 → K＋ K- ） and A CP （D0 →π＋ π- ）. This is the first evidence of CP violation in a charm system, which may indicate new physics beyond the Standard Model. Motivated by this measurement, we review rare processes in charmonium decay, especially, the weak decay, C or P violated decay, and lepton flavor violated decays. In case the new physics appears in charm sector, these rare decays of charmonium states will provide an opportunity to search for significant contributions from physics beyond the Standard Model. With huge J/ψ and ψ（2S） samples in BES experiment, the rare decays may be feasible.

Prospects for rare and forbidden hyperon decays at BESⅢ

The study of hyperon decays at the Beijing Electron Spectrometer Ⅲ （BESⅢ） is proposed to investigate the events of J/φ decay into hyperon pairs, which provide a pristine experimental environment at the Beijing Electron-Positron Collider Ⅱ. About 10^6-10^8 hyperons, i.e., ∧, ∑, ∈, and Ω, will be produced in the J/φ and φ（2S） decays with the proposed data samples at BESⅢ. Based on these samples, the measurement sensitivity of the branching fractions of the hyperon decays is in the range of 10^-5-10^-8. In addition, with the known center-of-mass energy and ＂tag technique＂, rare decays and decays with invisible final states can be probed.

Sensitivity study of searching for τ^-→γμ^- at HIEPA

The charged lepton flavor violation process is a clean and sensitive probe of new physics beyond the Standard Model. A sensitivity study is performed to the process τ^-→γμ^- based on a 3 fb^(-1) inclusive Monte Carlo sample of e^+e^- collisions at a center-of-mass energy of4.26 or 4.6 Ge V, in the framework of the BESIII software system. The 90 % confidence level upper limits on B(τ^-→γμ^-) are estimated assuming no signal is produced. We also obtain the sensitivity on B(τ^-→γμ^-) as a function of the integrated luminosity, to serve as a reference for the HIEPA being proposed in China. It is found that 6.34 ab^(-1) are needed to reach the current best upper limit of 4:4 10^(-8) and about 2510 ab^(-1) are needed to reach a sensitivity of 10^(-9) if the detector design is similar to that of BESIII.

Implications of fermionic dark matter on recent neutrino oscillation data

We investigate flavor phenomenology and dark matter in the context of the scotogenic model.In this model,the neutrino masses are generated through radiative corrections at the one-loop level.Considering the neutrino mixing matrix to be of tri-bimaximal form with additional perturbations to accommodate the recently observed nonzero value of the reactor mixing angle θ（13）,we obtain the relation between various neutrino oscillation parameters and the model parameters.Working in a degenerate heavy neutrino mass spectrum,we obtain light neutrino masses obeying the normal hierarchy and also study the relic abundance of fermionic dark matter candidates,including coannihilation effects.A viable parameter space is thus obtained,consistent with neutrino oscillation data,relic abundance and various lepton flavor violating decays such as 1α→1（βγ） and 1α→31β.

Z→l_i~±l_j~■ jprocesses in the BLMSSM

In a supersymmetric extension of the Standard Model（SM） where baryon and lepton numbers are local gauge symmetries（BLMSSM）, we investigate the charged lepton flavor violating（CLFV） processes Z→li^±lj^ jafter introducing new gauginos and right-handed neutrinos. In this model, the branching ratios of Z→li^±lj^ jare around（10^-8–10^-10）, which approach the present experimental upper bounds. We hope that the branching ratios for these CLFV processes can be detected in the near future.

Implications of the RK and R_(K*) anomalies

We discuss the implications of the recently reported R_K and R_（K＊） anomalies, the lepton flavor nonuniversality in the B → Kl~＋l^-and B → K~＊l~＋~l- decay channels. Using two sets of hadronic inputs of form factors, we perform a fit of new physics to the R_K and R_（K＊） data, and significant new physics contributions are found. We suggest the study of lepton flavor universality in a number of related rare B,Bs,Bc and Λb decay channels, and in particular we give predictions for the μ-to-e ratios of decay widths with different polarizations of the final state particles, and of the b → dl~＋l^- processes, which are presumably more sensitive to the structure of the underlying new physics. With the new physics contributions embedded in the Wilson coefficients, we present theoretical predictions for lepton flavor non-universality in these processes.