0000000000407082
AUTHOR
Xue-qian Li
showing 5 related works from this author
Anomalous Higgs–top-quark couplings in the MSSM
2004
The anomalous couplings of the top quark and the Higgs boson have been studied in an effective theory deduced from the minimal supersymmetric extension of the standard model as the heavy fields are integrated out. Constraints on the parameters of the model from the experimental data of ${R}_{b}=\ensuremath{\Gamma}(\stackrel{\ensuremath{\rightarrow}}{Z}b\overline{b})/\ensuremath{\Gamma}(\stackrel{\ensuremath{\rightarrow}}{Z}\mathrm{hadrons})$ are obtained.
Two-loop gluino contributions to the neutron electric dipole moment in theCP-violating minimal supersymmetric standard model
2005
We analyze two-loop gluino corrections to the neutron electric dipole moment (EDM) in the minimal supersymmetry extension of the standard model (MSSM). The dependence of two-loop corrections on the relevant CP violating phases differs from that of the one-loop contributions, and there is a region in the parameter space where the two-loop contributions are comparable with the one-loop contributions. Our numerical results show that the two-loop corrections can be as large as 30% of the one-loop results.
The two-loop supersymmetric corrections to lepton anomalous magnetic and electric dipole moments
2006
Using the effective Lagrangian method, we analyze the electroweak corrections to the anomalous dipole moments of lepton from some special two-loop topological diagrams which are composed of neutralino (chargino) - slepton (sneutrino) in the minimal supersymmetric extension of the standard model (MSSM). Considering the translational invariance of the inner loop momenta and the electromagnetic gauge invariance, we get all dimension 6 operators and derive their coefficients. After applying equations of motion to the external leptons, the anomalous dipole moments of lepton are obtained. The numerical results imply that there is a parameter space where the two-loop supersymmetric corrections to …
Spectra of the lightest baryons containing two heavy quarks in a potential model
2000
The spectra of baryons which include two heavy quarks can be treated as a two-body system, where the two heavy quarks constitute a bosonic diquark. We derive the effective potential between the light quark and the heavy diquark in terms of the Bethe-Salpeter equation. To obtain the spectra, several serious problems need to be solved: (1) the operator ordering, (2) the errors caused by the nonrelativistic expansion, (3) spin-spin coupling, and (4) the mixing between the scalar-diquark-baryon and vector-diquark-baryon. In this work we take reasonable approaches to deal with them.
Observation of the doubly radiative decay η′→γγπ0
2017
Based on a sample of 1.31 billion J/psi events collected with the BESIII detector, we report the study of the doubly radiative decay eta' -> gamma gamma pi(0) for the first time, where the eta' meson is produced via the J/psi -> gamma eta' decay. The branching fraction of eta' -> gamma gamma pi(0) inclusive decay is measured to be B(eta' -> gamma gamma pi(0))(Incl) = (3.20 +/- 0.07(stat) +/- 0.23(sys)) x 10(-3), while the branching fractions of the dominant process eta' -> gamma omega and the non-resonant component are determined to be B(eta' -> gamma omega) x B(omega -> gamma pi(0)) = (23.7 +/- 1.4(stat) +/- 1.8(sys)) x 10(-4) and B(eta' -> gamma gamma pi(0))(NR) = (6.16 +/- 0.64(stat) +/-…