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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 {2. university,Xinxiang 453007,china 2.Institute of Theoretical physics,Chinese Academy of Sciences,Beijing 100190,china 1. department of physics Henan Normal University Xinxiang 453007 China2. Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 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

Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science china(physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2. TANG Jun 2., ZHANG AiHua 3 & JIA Ya 2.1 department of physics, Lanzhou {2. of Technology, Lanzhou 730050, china 2.department of physics, Central china normal {2., Wuhan 430079, china 3 College of Electrical and Information Engineering, Lanzhou {2. of Technology, Lanzhou 730050, china 1. department of physics Lanzhou University of Technology Lanzhou 730050 China2. Department of Physics Central China Normal University Wuhan 430079 China3. College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

Constraints on Cardassian universe from Gamma ray bursts

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1720-1725页

作者： WANG TaiShan1 & LIANG Nan2.1 department of physics & Center for Astrophysics,Tsinghua university,Beijing 100084,china 2.department of Astronomy,Beijing normal university,Beijing 100875,china 1. department of physics & Center for Astrophysics Tsinghua University Beijing 100084 China2. Department of Astronomy Beijing Normal University Beijing 100875 China

Constraints on the original Cardassian model and the modified polytropic Cardassian model are examined from the recently derived 42.gamma-ray bursts(GRBs) data calibrated with the method that can avoid the circularity *** results show that GRBs can be an optional observation to constrain the Cardassian *** the GRBs data with the newly de-rived size of baryonic acoustic oscillation peak from the Sloan Digital Sky Survey(SDSS),and the position of the first acoustic peak of the Cosmic Microwave Background radiation(CMB) from Wilkinson Microwave Anisotropy Probe(WMAP),we find Ωm0=0.2.+0.02.0.02.n=0.06+0.07-0.08(1σ) for the original Cardassian model,and Ωm0=0.2.+0.2.-0.02.n=-0.09+0.2.-1.91,β=0.82.2.10-0.62.1σ) for the modified polytropic Cardassian model.

关键词： Cardassian Gamma ray burst Cosmic Microwave Background baryonic acoustic oscillation

MULTIPLE POSITIVE SOLUTIONS OF SINGULAR THIRD-ORDER PERIODIC BOUNDARY VALUE PROBLEM

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Acta Mathematica Scientia 2005年第1期25卷 81-88页

作者：孙经先刘衍胜 department of Mathematics Xuzhou normal {2. Xuzhou 221116 China department of Mathematics shandong normal university Jinan 250014 China

This paper deals with the singular nonlinear third-order periodic boundary value problem u'' + p(3)u = f (t, u), 0 less than or equal to t less than or equal to 2.i, with u((i)) (0) = u((i)) (2.i), i = 0, 1, 2. where p is an element of (Graphics) and f is singular at t = 0, t = 1 and u = 0. Under suitable weaker conditions than those of [1], it is proved by constructing a special cone in C[0, 2.i] and employing the fixed point index theory that the problem has at least one or at least two positive solutions.

关键词： singular boundary value problem third-order differential system positive solution

On Holomorphic Automorphisms of a Class of Non-homogeneous Rigid Hypersurfaces in C^(N+1)

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Chinese Annals of Mathematics,Series B 2010年第2期31卷 201-210页

作者： Qingyan WU department of Mathematics,Linyi normal {2.,Linyi 2.6005,shandong,china department of Mathematics,Zhejiang {2.,Hangzhou 31002.,china department of Mathematics Linyi Normal University Linyi 276005 Shandong China department of Mathematics Zhejiang University Hangzhou 310027 China

The author determines the real-analytic infinitesimal CR automorphisms of a class of non-homogeneous rigid hypersurfaces in CN+1 near the origin,and the connected component containing the identity transformation of al... 详细信息

关键词： Real-analytic infinitesimal CR automorphisms Rigid hypersurfaces Holomorphic automorphisms

The information entropy of a static dilaton black hole

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Science china(physics,Mechanics & Astronomy) 2008年第2期51卷 113-125页

作者： LIU ChengZhou Institute of Theoretical physics, Binzhou university, Binzhou 2.6600,{2. department of physics, Beijing normal university, Beijing 100875,{2. 1. Institute of Theoretical physics Binzhou University Binzhou 256600 China 2. department of physics Beijing Normal University Beijing 100875 China

In accordance with holographic principle, by calculating the statistical entropy of the quantum field just at the event horizon of the Garfinkle-Horowitz-Strominger dilaton black hole, the information entropy of the black hole was investigated and the Bekenstein-Hawking formula was obtained. The results show that black hole entropy is identical with the statistical entropy of the quantum field at the horizon. Using the generalized uncertainty relation, the divergence of the state density near the event horizon in usual quantum field theory was removed, and the cutoffs and the little mass approximation in the heat gas method of black hole entropy were avoided. Thus, the microstates of the massive scalar field just at the event horizon of the static dilaton black hole were studied directly and a description on holograph principle was presented. By using residue theorem, the integral difficulty in the calculation was overcome, and the information entropy and the Bekenstein-Hawking formula were obtained quantitatively. Compared with the black hole entropy from the loop quantum gravity, the consistency of methods and results of calculating black hole entropy in non-commutative quantum field theory and loop quantum gravity was investigated. By this, the gravity correction constant in the generalized uncertainty relation was suggested and the sense of holographic principle was discussed.

关键词： black hole entropy holographic principle non-commutative quantum field theory event horizon loop quantum gravity

Imaging theory of nonlinear second harmonic and third harmonic generations in confocal microscopy

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Science china(physics,Mechanics & Astronomy) 2004年第1期47卷 8-16页

作者： TANG Zhilie1, XING Da2.& LIU Songhao2.1. department of physics, South{2. normal university, Guangzhou 510631,{2. 2. School for Information and Optoelectronic Science and Engineering, South{2. normal university, Guangzhou 510631,{2. Correspondence should be addressed to Tang Zhilie (email: tangzhl@***) Received April 2., 2.03 1. department of physics South China Normal University 510631 Guangzhou China 2. School for Information and Optoelectronic Science and Engineering South China Normal University 510631 Guangzhou China

The imaging theory of nonlinear second harmonic generation (SHG) and third harmonic generation (THG) in confocal microscopy is presented in this paper. The nonlinear effect of SHG and THG on the imaging properties of confocal microscopy has been analyzed in detail by the imaging theory. It is proved that the imaging process of SHG and THG in confocal microscopy, which is different from conventional coherent imaging or incoherent imaging, can be divided into two different processes of coherent imaging. The three-dimensional point spread functions (3D-PSF) of SHG and THG confocal microscopy are derived based on the nonlinear principles of SHG and THG. The imaging properties of SHG and THG confocal microscopy are discussed in detail according to its 3D-PSF. It is shown that the resolution of SHG and THG confocal microscopy is higher than that of single- and two-photon confocal microscopy.

关键词： second harmonic generation, third harmonic generation, confocal microscopy, three-dimensional point spread function.

Quantum dynamics study for reaction of H_2.+ OD→H + HOD

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Chinese Science Bulletin 1997年第2期42卷 116-120页

作者： ZHANG Yici, ZHANG Yanbing, ZHANG DeshengZHANG Qinggang, Dong H. Zhang and John Z. H. Zhang1. department of physics, {2. Teachers university, jinan 250014, china 2. department of Chemistry, New York Uni versity, New York 10003, USA department of physics Shandong Teachers University Jinan 250014 China

TIME-dependent （TD） quantum wave packet theory, with a relatively small amount of computational effort, has been widely used in quantum dynamics calculation of atom and molecule reaction scattering. Many computational scaling advantages of the TD method can be found apparently in polyatomic system. In this note, by using the TD quantum wave packet method with the potential-averaged 5D model （PA5D）, we give the calculated results of reaction probabilities, cross sections and rate constants for the H2./sub> + OD reaction. The energyprojection method is used to transform the TD wave function into the TI (energy-indepen-

关键词： propagation probability cross section rate constant.

Image interpretation of weak-coupling N-mer adsorbate's STM system

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Chinese Science Bulletin 1997年第5期42卷 371-374页

作者： HUANG Xintang, Ql Shouren, LI Xinjiao and LI Yongping1 department of physics, Central{2. normal university, Wuhan 430070,{2. department of Solid State Electronics, Huazhong university of Science and Technology, Wuhan 430074,{2. 2. department of physics, university of Science and Technology of{2., Hefei 2.002.,{2. department of physics Central China Normal University Wuhan China department of Solid State Electronics Huazhong University of Science and Techndogy Wuhan China department of physics University of Science and Technology of China Hefei China

Up to now, there have been many indistinctive points in the image interpretation of scanning tunnelhng microscopy (STM) system, and the problems have attracted almost all STM scientists’ attention. In 1992. Kenkre proposed the new programme which describes the behaviour of the electrons moving in the STM tunnelling by the method of exciton dynamics, and the programme not only breaks through the restrictions of Tersoff-Hamann theory, but also can be applied conveniently to discussing the effects of the tip structure, adsorbate structure, substrate structure, temperature, tunneling voltage, and the degree of coherence of elec-

关键词： weak-coupling N-mer adsorbates STM image interpretation exciton dynamics method.