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The lepton flavor violating signal of the extra gauge boson Z′in photon-photon collision at the ILC

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1992-1997页

作者： LIU GuoLi 1,2.1 physics Department,Zhengzhou University,Zhengzhou 450001,china 2.Kavli I{2. for {3. physics china,Chinese academy of sciences,Beijing 100190,china physics Department Zhengzhou University Zhengzhou China Kavli Institute for theoretical {2.{3. Chinese Academy of Sciences Beijing China

The hitherto unconstrained lepton flavor mixings,induced by the new gauge boson Z ,which are the prediction of many new physics models,such as topcolor-assisted technicolor (TC2. models and flavor-universal TC2.models,may lead to the lepton flavor violating productions of τμˉ,τeˉ and μeˉ in photon-photon collision at the proposed International Linear Collider (ILC).Through a comparative analysis of these processes,we find that the better channel to probe the new physics models is the production of τμˉ or τeˉ which occurs at a much higher rate than μeˉ production due to the large mixing angle and the large flavor changing coupling,and may reach the detectable level of the ILC for a large part of the parameter *** the rates predicted by the Standard Model are far below the detectable level,these processes may serve as a sensitive probe for such new physics models.

关键词： new gauge boson Z lepton flavor violating processes photon-photon

Comparison of dark energy models:A perspective from the latest observational data

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： LI Miao1,2.LI XiaoDong2.3.& ZHANG Xin1,4 1Kavli Institute for {2. physics{3.,Chinese academy of sciences,Beijing 100190,china 2.ey Laboratory of Frontiers in {2. physics,Institute of {2. physics,Chinese academy of sciences,Beijing 100190,china 3.nterdisciplinary Center for {2. Study,University of Science and Technology of{3.,Hefei 2.0}02.,china 4Department of physics,College of sciences,Northeastern University,Shenyang 110004,china Kavli Institute for theoretical {2.{3. Chinese Academy of Sciences Beijing China Key Laboratory of Frontiers in theoretical physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Interdisciplinary Center for theoretical Study University of Science and Technology of China Hefei China Department of physics College of Sciences Northeastern University Shenyang China

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble Space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-Linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria

Lepton flavor violating Z-boson decays at GigaZ as a probe of supersymmetry

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1949-1952页

作者： YANG JinMin 1,2.1 Department of physics,Henan Normal University,Xinxiang 453.07,{2. 2.Institute of {3. physics,Chinese academy of sciences,Beijing 100190,{2. Department of physics Henan Normal University Xinxiang China Institute of theoretical {2. Chinese Academy of Sciences Beijing China

This paper briefly reviews the lepton flavor violating Z-decays at GigaZ as a probe of supersymmetry by focusing on Z → i j in two representative supersymmetric models: the minimal supersymmetric model without R-parity and the supersymmetric seesaw *** work concludes that under the current experimental constraints from LEP and i → j γ,these rare decays can still be enhanced to reach the sensitivity of the ***,supersymmetry can be probed via these decays at GigaZ.

关键词： Z-decay GigaZ supersymmetry

Strong decays of N~*(153.) in an extended chiral quark model

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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2.3.& ZOU BingSong1,2.3.1 I{2. of High Energy physics,Chinese academy of {3.,Beijing 100049,china 2.theoretical physics Center for Science Facilities,Chinese academy of {3.,Beijing 100049,china 3.Graduate University of Chinese academy of {3.,Beijing 100049,china Institute of High Energy physics Chinese Academy of Sciences Beijing China theoretical physics Center for Science Facilities Chinese Academy of Sciences Beijing China Graduate University of Chinese academy of sciences Beijing China

The strong decays of the N*(153.) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(153.) contribute significantly to the N*(153.) → Nπ and N*(153.) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(153.) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(153.) strong decays five-quark components

The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china(physics,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1, ZHANG Yanhui1, WANG Dehua2. DU Mengli3.& LIN Shenglu1 1. College of physics and Electronics, Shandong Normal University, Jinan 2.0014,{2. 2. Department of Mathematics and physics, Shandong I{3. of Architecture and Engineering, Jinan 2.0014,{2. 3. I{3. of theoretical physics, Chinese academy of sciences, Beijing 100080,{2. College of physics and Electronics Shandong Normal University Jinan China Department of Mathematics and physics Shandong Institute of Architecture and Engineering Jinan China Institute of theoretical {2. Chinese Academy of Sciences Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 2.. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

Systematic study of survival probability of excited superheavy nuclei

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 109-113页

作者： XIA ChengJun1, SUN BaoXi1, ZHAO EnGuang2.3.& ZHOU ShanGui2.3.1College of Applied {2., Beijing University of Technology, Beijing 10012., china 2.nstitute of theoretical physics, Chinese {3. of {2., Beijing 100190, china 3.enter of theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 73.000, china College of Applied sciences Beijing University of Technology Beijing China Institute of theoretical {2. Chinese Academy of Sciences Beijing China Center of theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China

The stability of excited superheavy nuclei (SHN) with 100 Z 13. against neutron emission and fission is investigated by using a statistical model. In particular, a systematic study of the survival probability against fission in the 1n-channel of these SHN is made. The present calculations consistently take the neutron separation energies and shell correction energies from the calculated results of the finite range droplet model which predicts an island of stability of SHN around Z = 115 and N = 179. It turns out that this island of stability persists for excited SHN in the sense that the calculated survival probabilities in the 1n-channel of excited SHN at the optimal excitation energy are maximized around Z = 115 and N = 179. This indicates that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects.

关键词： survival probability superheavy elements island of stability neutron emission fission

Two Higgs bi-doublet left-right model with spontaneous P and CP violation

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Science china(physics,Mechanics & Astronomy) 2008年第12期51卷 1808-1825页

作者： WU YueLiang 1↑ & ZHOU YuFeng2.1 Kavli Institute for theoretical {2.{3., Institute of theoretical {2., Chinese academy of Sci- ences, Beijing 100190,{3. 2.KEK, Tsukuba, 3.5-0801, Japan Kavli Institute for theoretical {2.{3. Institute of Theoretical Physics Chinese Academy of Sciences Beijing China KEK Tsukuba Japan

A left-right symmetric model with two Higgs bi-doublet is shown to be a consistent model for both spontaneous P and CP violation. The flavor changing neutral cur- rents can be suppressed by the mechanism of approximate global U(1) family symmetry. The constraints from neural K meson mass difference ΔmK are calcu- lated and it is demonstrated that a right-handed gauge boson W2.contribution in box-diagrams with mass well below 1 TeV is allowed due to a cancelation caused by a light-charged Higgs boson with a mass range of 150-3.0 GeV. The W2.con- tribution to εK can be suppressed from an appropriate choice of additional CP phases appearing in the right-handed Cabbibo-Kobayashi-Maskawa matrix. The model is also found to be fully consistent with B0 mass difference ΔmB and the mixing induced CP violation sin2.J/ψ , which is usually difficult for the model with only one Higgs bi-doublet. The new physics beyond the standard model can be directly searched at the colliders LHC and ILC.

关键词： left-right symmetry spontaneous P and CP violation two Higgs bi-doublets new physics

Global analysis theory of climate system and its applications

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Chinese Science Bulletin 2003年第10期48卷 1034-1039页

作者： LI Jianping1,2.& CHOU Jifan2.3.1. LASG, Institute of Atmospheric {2., Chinese academy of {3., Beijing 10002., china 2. Department of Atmospheric {3., Lanzhou University, Lanzhou 73.000, china 3. Training Center for china Meteorological Administration, Beijing 100081, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric sciences Lanzhou University Lanzhou 730000 China Training Center for china Meteorological Administration Beijing 100081 China

The idea and main theoretical results of the global analysis theory of climate system are briefly summarized in this paper. A theorem on the global behavior of climate system is given, i.e. there exists a global attractor in the dynamical equations of climate, any state of climate system will be evolved into the global attractor as time increases, indicating the nonlinear adjustment process of climate system to external forcing. The different effects of external forcing, dissipation and nonlinearity on the long-term behavior of solutions are pointed out, and some main applications of the global analysis theory are also introduced. Especially, three applications, the adjustment and evolution processes of climate, the principle of numerical model design and the optimally numerical integration, are discussed.

关键词：整体分析理论气侯体系应用不定性计算法则气侯科学数字模型

Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 189-198页

作者： RONG Jian1 & MA Zhongyu1,2.3.1. china I{2. of Atomic Energy, Beijing 102.13. china 2. Center of Nuclear {3. physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lan-zhou 73.000, china 3. I{2. of {3. physics, Chinese academy of sciences, Beijing 100080, china Correspondence should be addressed to Rong Jian (email: jrong@***) china Institute of Atomic Energy Beijing China Center of Nuclear theoretical physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China Institute of theoretical {2. Chinese Academy of Sciences Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.