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f(R) gravity and Maxwell equations from the holographic principle

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Science China(physics,Mechanics & Astronomy) 2012年第3期55卷 375-380页

作者： MIAO RongXin MENG Jun LI Miao interdisciplinary Center for theoretical Study University of Science and Technology of ChinaHefei 230026China Kavli institute for theoretical physics Key Laboratory of Frontiers in Theoretical PhysicsInstitute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

Extending the holographic program of our previous work,we derive f(R) gravity and the Maxwell equations from the holographic principle,using time-like holographic *** find that to derive the Einstein equations and f(R) gravity by a natural holographic approach,the quasi-static condition is *** also find the surface stress tensor and the surface electric current,surface magnetic current on a holographic screen for f(R) gravity and Maxwell's theory,respectively.

关键词： entropic gravity f(R) gravity Maxwell equations the holographic principle

Study of(e,2e) process on potassium at 6 e V-60 eV above threshold in a second-order Born approximation

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Chinese physics B 2012年第8期21卷 197-201页

作者：王旸周雅君焦利光 Center for theoretical Atomic and Molecular physics Academy of Fundamental and Interdisciplinary SciencesHarbin Institute of Technology

The standard distorted wave Born approximation （DWBA） method has been extended to second-order Born amplitude in order to describe the multiple interactions between the projectile and the atomic target. Second-order DWBA calculations have been preformed to investigate the triple differential cross sections （TDCS） of coplanar doubly symmetric （e, 2e） collisions for the alkali target potassium at excess energies of 6 eV-60 eV. Compared with the previous first-order DWBA calculations, the present theoretical model improves the degree of agreement with experiments, especially for the backward scattering angle region of TDCS. This indicates that the present second-order Born term is capable of giving a reasonable correction to the DWBA model in studying coplanar symmetric （e, 2e） problems in low and intermediate energy ranges.

关键词： second-order Born approximation (e 2e) collisions potassium triple differential cross section

Momentum-space calculation of electron-CO elastic collision

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Chinese physics B 2013年第2期22卷 214-217页

作者：王远成马佳周雅君 Center for theoretical Atomic and Molecular physics Academy of Fundamental and Interdisciplinary Sciences Harbin Institute of Technology

We report a momentum-space study on low-energy electron-CO *** differential cross sections（DCS） are obtained using a static-exchange-optical（SEO） model for the incident energies of 2,3,5,and 10 *** effect of higher reaction channels,including the ionization continuum,on the elastic collision is represented by an ab initio equivalent-local optical *** cross sections are compared with experimental measurements and other theoretical results.

关键词： electron scattering carbon monoxide differential cross section

Unnatural parity resonance states in positron-excited hydrogen scattering

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Chinese physics B 2012年第12期21卷 207-211页

作者：马佳周雅君王远成 Center for theoretical Atomic and Molecular physics Academy of Fundamental and Interdisciplinary SciencesHarbin Institute of Technology

The coupled-channels optical method for positron scattering has been applied to investigate resonance states with unnatural parities in a positron-excited hydrogen system. The positronium formation channels and continuum channel are included via a complex equivalent local potential. Resonance states with angular momenta L =- 1 to L = 2 and parities （-1）L＋1 are calculated. Resonance energies and widths are reported and compared with other theoretical calculations. We found that the opening positronium formation channels play an important role in forming nondipole Feshbach resonances.

关键词： positrons excited-hydrogen atom unnatural parity resonances positronium coupled-channels optical method

theoretical prediction of the optimal conditions for observing the stereodynamical vector properties of the C(~3P) + OH(X^2Π) → CO(X^1 Σ^+) + H(~2S) reaction

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Chinese physics B 2013年第12期22卷 491-496页

作者：王远鹏赵美玉姚舜怀宋朋马凤才 Department of physics Liaoning University institute of theoretical Simulation Chemistry Academy of Fundamental and Interdisciplinary Sciences Harbin Institute of Technology School of physics Peking University

The best optimal initial reactant state and collision energy for observing the stereodynamical vector properties of the title reaction in the ground electronic state X2A’ potential energy surface （PES）[Zanchet et al. 2006 J. Phys. Chem. A 110 12017] are theoretically predicted using the quasi-classical trajectory （QCT） method for the first time. The calculated results reveal that the smallest value of the rotational quantum number j, larger vibrational quantum number v, and the lower strength of collision energy should be selected for offering the most obvious picture about the stereodynamical vector properties. Polarization-dependent differential cross sections and the angular momentum alignment distribution, P（θr） and P（Φr） in the center-of-mass frame, are obtained to gain an insight into the alignment and orientation of the product molecules. The rotational angular momentum vector j’ of CO is aligned to be perpendicular to reagent relative velocity k. The product polarizations align along the y axis, pointing to the positive direction of the y axis. A new method is developed to investigate massive reactions with various initial states and to further study the vector properties of the fundamental reactions in detail.

关键词： quasi-classical trajectory initial states stereodynamics polarization collision energy

cluster expansion Mayer series canonical ensemble grand canonical ensemble

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Communications in theoretical physics 2016年第2期65卷 185-188页

作者：王先智 institute of theoretical and interdisciplinary physics Department of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240 China

Mayer derived the Mayer series from both the canonical ensemble and the grand canonical ensemble by use of the cluster expansion method. In 2002, we conjectured a recursion formula of the canonical partition function of a fluid(X.Z. Wang, Phys. Rev. E66(2002) 056102). In this paper we give a proof for this formula by developing an appropriate expansion of the integrand of the canonical partition function. We further derive the Mayer series solely from the canonical ensemble by use of this recursion formula.

关键词： Derivation of Mayer Series from Canonical Ensemble

Second-Order Born Effect in Single Ionization of Argon by Electron Impact

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Chinese physics Letters 2012年第1期29卷 102-104页

作者： WANG Yang ZHOU Ya-Jun JIAO Li-Guang Center for theoretical Atomic and Molecular physics Academy of Fundamental and Interdisciplinary SciencesHarbin Institute of TechnologyHarbin 150080

We extend the standard distorted wave Born approximation(DWBA)to include the second-order Born amplitude in order to describe the multiple interactions between a projectile and an atomic *** the first-and secondorder DWBA models are used to calculate triply differential cross sections(TDCS)of coplanar(e,2e)on atomic argon with the scattered electron energy fixed at 500eV,the scattering angle at 6°and the ejected electron energies at 37,74 and 205 e *** agreements with experimental measurements have been obtained in shape,and the second-order DWBA model improves the calculations as expected,especially for recoil peak of TDCS.

关键词： Electron scattered distorted

Electronic Excitation of H_(2) by Electron Impact Using Multichannel Static-Exchange-Optical Method

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Chinese physics Letters 2013年第7期30卷 64-67页

作者： WANG Yuan-Cheng MA Jia ZHOU Ya-Jun Center for theoretical Atomic and Molecular physics Academy of Fundamental and Interdisciplinary SciencesHarbin Institute of TechnologyHarbin 150081

The momentum-space multichannel static-exchange-optical model is applied to the electron-H_(2) collision at the two-state close-coupling *** cross sections for X^(1)Σ_(g) to b^(3)Σ_(u) transition at the energies of 20 and 30 eV are *** are compared with other theoretical results and experimental *** scattering cross sections are also presented and compared with other work.

关键词： level. Electron momentum

Solar cycles during the seventeenth century revealed by equatorial aurora records

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Earth and Planetary physics 2025年第1期9卷 182-187页

作者： Yong Wei LiMei Yan Key Laboratory of Earth and Planetary physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Solar cycles are fundamental to astrophysics,space exploration,technological infrastructure,and Earth's climate.A better understanding of these cycles and their history can aid in risk mitigation on Earth,while also deepening our knowledge of stellar physics and solar system *** the solar cycles between 1600 and 1700-especially the post-1645 Maunder Minimum,characterized by significantly reduced solar activity-poses challenges to existing solar activity *** study utilizes a new red equatorial auroral catalog from ancient Korean texts to establish solar cycle patterns from 1623 to ***,a further reevaluation of the solar cycles between 1610 and 1755 identified a total of 13 cycles,diverging from the widely accepted record of 12 cycles during that *** research enhances our understanding of historical solar activity,and underscores the importance of integrating diverse historical sources into modern analyses.

关键词： solar cycle Maunder Minimum solar activity red equatorial aurora West Pacific geomagnetic anomaly