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Testing local realism in P → VV decays

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science china({2.,Mechanics & Astronomy) 2010年第5期53卷 870-875页

作者： LI JunLi1 & QIAO CongFeng1,2.1Department of physics,Graduate University of chinese {2. of {3.s,Beijing 100049,china 2.5} physics center for {3. facilities(TPCSF),chinese {2. of {3.s,Beijing 100049,china 1. Department of physics Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Theoretical Physics Center for Science Facilities (TPCSF) Chinese Academy of Sciences Beijing 100049 China

It was found that the vector meson pair from the pseudoscalar decays can form an entangled *** this work we give out detailed explanations on the polarization correlation of the two entangled vector *** is demonstrated that an experimental test of the Clauser-Horne inequality can be carried out through measuring the azimuthal distribution of four pseudoscalars in the cascade decay ηc→ VV →(PP)(PP),and the measurement of this process is feasible with the current running experiments in tau-charm ***,a brief discussion on the polarization correlation of the two vector mesons from B → VV decays is also presented.

关键词： nonlocality test high energy experiment meson decays

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(2..5) bulk metallic glass up to 2. GPa

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science china({2.,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., LIU Jing 3., YUN Jinku 1 , SUN Liling 2., LIU Riping 1 , ZHANG Jun 2.& WANG Wenkui 1, 2.1. Key Laboratory of Metastable Materials science and Technology, Yanshan University, Qinhuangdao 066004, {2. 2. {2. for Condensed Matter {3., Institute of {3., chinese academy of sciences, Beijing 100080, {2. 3. BSRF, Institute of High Energy {3., chinese academy of sciences, Beijing 10003., {2. 1. Key Laboratory of Metastable Materials science and Technology Yanshan University 066004 Qinhuangdao China 2. center for Condensed Matter physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3.& WANG Huijun2.1. Nansen-Zhu International Research center, Institute of Atmospheric {2., {2. {3. of sciences, Beijing 10002., china 2. Department of Atmospheric science, Yunnan University, Kunming 650091, china 3. Graduate University of the {2. {3. of sciences, Beijing 100049, china 1. Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric science Yunnan University Kunming 650091 China 3. Graduate University of the chinese {2. of {2.s Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

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 theoretical {2. {2.,{3. academy of sciences,Beijing 100190,{2. 2.ey Laboratory of Frontiers in theoretical {2.,Institute of theoretical {2.,{3. academy of sciences,Beijing 100190,{2. 3.nterdisciplinary center for theoretical Study,University of science and Technology of {2.,Hefei 2.0}02.,{2. 4Department of {2.,College of sciences,Northeastern University,Shenyang 110004,{2. 1. Kavli Institute for theoretical physics {2. Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China3. Interdisciplinary Center for Theoretical Study University of Science and Technology of China Hefei 230026 China4. Department of Physics College of Sciences Northeastern University Shenyang 110004 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

Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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science china Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2. HONG Xiaozhong3. GU Fang1 & BA Xinwu1 1. College of Chemistry and Environment science, Hebei University, Baoding 071002. {2. 2. International {2. for Materials {3., chinese academy of sciences, Shenyang 110016, {2. 3. College of {3. science and Technology, Hebei University, Baoding 071002. {2. 1. College of Chemistry and Environment science Hebei University Baoding 071002 China 2. International center for Materials physics Chinese Academy of Sciences Shenyang 110016 China 3. College of physics {2. and Technology Hebei University Baoding 071002 China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

Light A physics in the lepton-specific two-Higgs doublet model

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science china({2.,Mechanics & Astronomy) 2010年第11期53卷 1981-1987页

作者： CAO JunJie 1,HENG ZhaoXia 2.3.& WAN PeiHua 1 1 College of physics & Information Engineering,Henan Normal University,Xinxiang 453.07,china 2.Key Laboratory of Frontiers in {2. physics,Institute of {2. physics,chinese academy of sciences,Beijing 100190,china 3.Kavli Institute for {2. physics china,chinese academy of sciences,Beijing 100190,china 1. College of physics & Information Engineering Henan Normal University Xinxiang 453007 China2. Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China3. Kavli Institute for Theoretical Physics China Chinese Academy of Sciences Beijing 100190 China

We examine various direct and indirect constraints on the lepton-specific two-Higgs doublet model and discuss its phenomenology at colliders in the allowed parameter *** constraints we consider come from the precision electroweak data,the direct search for Higgs boson,the muon anomalous magnetic moment,as well as some theoretical consistency *** find that in the allowed parameter space the CP-odd Higgs boson A is rather light (m A 3. GeV with 95% possibility),which is composed dominantly by the leptonic Higgs and decays dominantly into τ + τ;while the SM-like Higgs boson h (responsible largely for electroweak symmetry breaking) decays dominantly in the mode h → AA → 4τ with a large decay width,which will make the Higgs discovery more difficult at the ***,this scenario predicts rare Z decays Z → AAA and Z →τ + τA with their branching ratios ranging from 10-8 to 10-and 10-5 to 10-4 respectively,which may be accessible at the GigaZ option of the ILC.

关键词： Lepton-specific two-Higgs doublt model light Higgs boson A Z decays

Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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science china(Technological sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2. GU Yidong3. LIN Baojun3.& GUO Jiong3.1. center for Space science and Applied Research, {2. {3. of sciences, Beijing 100080, china 2. Graduate School of the {2. {3. of sciences, Beijing 10003., china 3. General Establishment of Space science and Application, {2. {3. of sciences, Beijing 100080, china Correspondence should be addressed to L Congmin 1. center for Space science and Applied Research Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the chinese academy of {2.s 100039 Beijing China 3. General Establishment of Space science and Application Chinese Academy of Sciences 100080 Beijing China

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2.m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

Approaches to improving critical current density of YBCO superconducting thick films deposited by electrophoresis

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science china({2.,Mechanics & Astronomy) 2004年第2期47卷 165-172页

作者： ZHU Yabin1,2. ZHOU Yueliang2. LIU Zhen2. WANG Shufang2. CHEN Zhenghao2. L?Huibin2. YANG Guozhen2. XIAO Ling3. REN Hongtao3. JIAO Yulei3.& ZHENG Minghui3.1. Department of physics, College of science, Beijing Jiaotong University, Beijing 100044, {2. 2. Laboratory of Optical physics, Institute of physics and center for Condensed Matter physics, chinese {12. of sciences, Beijing 100080, {2. 3. General Research Institute for Nonferrous Metals, Beijing 100088, {2. Correspondence should be addressed to Zhu Yabin (email: ybzhu@***) 1. Department of physics College of Science Beijing Jiaotong University 100044 Beijing China 2. Laboratory of Optical physics Institute of physics and {2. for Condensed Matter physics Chinese Academy of Sciences 100080 Beijing China 3. General Research Institute for Nonferrous Metals 100088 Beijing China

Fabrication of YBCO superconducting thick films by electrophoresis has been widely reported. However, the value of critical current density (J c) is far from what the practical application requires. The superconducting thick films are obtained using top-seeded melt growth method with different proportional Y2.aCuO5 (Y2.1) addition. High-pressure oxygen has been used in the annealing process to improve the uniformity of the oxygen content in the superconducting thick films. When 40mol% Y2.1 powder is added to the YBa2.u3.7–5 (Y12.0} powder,J c for the superconducting thick film by approaches described above reaches 7.008×103.A/cm2.(77 K, 0 T), which is greater than the value ever reported.

关键词： YBCO thick films, electrophoretic deposition, melt-textured.

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

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science china({2.,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 Institute for {2. physics china,chinese academy of sciences,Beijing 100190,china 1. physics Department Zhengzhou University Zhengzhou 450001 China2. Kavli Institute for Theoretical Physics China Chinese Academy of Sciences Beijing 100190 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