Calculation of Higher-Order Foldy-Wouthuysen Transformation Hamiltonian

The Foldy-Wouthuysen Hamiltonian of a light atomic system that has an ma^8 contribution to energy levels is calculated. The case of a Dirac-Coulomb field is discussed. The results can be used for relativistic and radiative corrections to energy levels in the low-energy part. A divergent operator δ^2（r） emerges. This is probably due to the nature of the point-like charge source. The effective method of radiation calculation may be re-checked.     

SUSY Confinement

In response to the present status that searching for SUSY particles has been unsuccessful, we propose a bold scenario that SUSY particles are confined inside hadrons with a required condition of PR = 1 in analog to the color confinement for quarks. The scenario seems to be able to reconcile the beautiful SUSY theory and non-observation at present experiments. On other aspects, some loopholes in the proposal emerge and require to be answered in the future research.     

Comprehensive analysis of e+e-→γηc(2S)

We discuss the production of η_c(2S) through the process e⁺e^-→γη_c(2S), where the leading contribution originates from 1-loop electroweak corrections. Adopting some reasonable light-cone distribution amplitudes, we analyze the cross section of this process. As the electron-positron center of mass energy √s=3770 MeV, the typical production cross section of this process is about 1 fb.     

Top quark forward-backward asymmetry in the little Higgs model

A sizable difference in top quark pair forward backward asymmetry (AFB) is observed at Tevatron. The discrepancy triggers many new physics beyond the standard model (SM) and then constrains the parameter spaces in them. In this article we calculate the AFB of the top-pair production at Tevatron up to next to leading order (NLO) in the little Higgs model (LHM). We find that the contribution of Z_H can be large enough to make up the gap between SM prediction and experimental data. Then, the parameter space for the couplings between Z_H and quarks are constrained. Thus, this model can fulfill the experimental data, both in AFB and in cross section.     

One-loop QCD contribution to the potential of QQ

Without the non-relativistic approximation in one-loop function, the dominating one-loop contribution to the quark-antiquark potential is studied numerically in terms of perturbative Quantum Chromo Dynamics (QCD). For Coulomb-like potential, the ratio of the one-loop correction to the tree diagram contribution is presented, whose absolute value is about 20%. Our result is consistent with the analysis that the one-loop contribution should be suppressed by a factor α_s/π to the leading order contribution. This work can deepen the comprehension of α_s in Cornel potential.     

B~0-B~0 Mixing in Local Gauged Baryon and Lepton Numbers

Using the effective Hamiltonian method, we analyze the B0-B0 mixing in the extension of the standard model （SM） where baryon number and lepton number are local gauge symmetries. The numerical results indicate the correction from the extra particles to the mass difference ArnB is significant. There is a 60% enhancement compared to the SM prediction for AraB at most, which agrees with the current experimental result.     

大学物理课程考试方法改革与实践

大学物理课程兼有传授科学知识和科学素质培养的双重作用,相应的课程改革一直在进行,而与之紧密相连的考试方法改革也应该进行.为了能够更全面客观地考核学生的学习效果,在累加式考试的基础上增大了平时测试的比例,进行随堂测试、演示实验分析、研究性作业.实践表明这种考试改革取得了良好的效果.     

Top quark decay to a 125 GeV Higgs in the BLMSSM

In this paper, we calculate the rare top quark decay t → ch in a supersymmetric extension of the Standard Model where baryon and lepton numbers are local gauge symmetries. Adopting reasonable assumptions on the parameter space, we nd that the branching ratios of t→ch can reach 10^-3, which could be detected in the near future.     

Study of ψ(4415) in the QPC model

Some authors consider the ψ(4415) to be the 4S or 5S excited tate of a cc pair. Starting from this assumption, we study he decays of the ψ(4415) to DD, D^*D^*, D_SD_S, D_S^*D_S^*, and get the corresponding branching ratios in terms of the Quark-Pair-Creation (QPC) model. Compared with the experimental data, we find that the results of 4S state agree much better than those of the 5S state. Therefore, it is more reasonable to assume the ψ(4415) to be a 4S state.