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Near infrared lights emission of ^(40)Ar^(16+) impacting on metal surfaces

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Science china(physics,Mechanics & Astronomy) 2009年第7期52卷 1021-1026页

作者： ZHANG XiaoAn1,2. XIAO GuoQing2. YANG ZhiHu2. WANG Li1 & ZHAN WenLong2.1 department of physics,{2., xianyang 712000, china 2.Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china department of physics Xianyang Normal University Xianyang China Institute of Modern physics Chinese Academy of Sciences Lanzhou China

The highly charged ion 40Ar16+ with the velocity (kinetic energy EK=150 keV, velocity V=8.5×105 m/s) smaller than Bohr velocity (VBohr=2.9×106 m/s) was found to hove impacts on the surfaces of metals Ni, Mo, Au and Al, and the Ar atomic infrared light lines and X-rays spectra were simultaneously measured. The experimental results show that the highly charged ion that captures electrons is neutralized, and the multiply-excited hollow atom forms. The hollow atom cascade decay radiates lights from infrared to X-ray spectrum. The intensity of infrared lights shows that the metallic work functions play an important role in the neutralization process of highly charged ions during their interaction with metallic surfaces, which verifies the classical over-the-barrier model.

关键词： infrared light lines X-ray neutralization highly charged ions

X-ray spectra induced by ^(12.)Xe^(q+) impacting the metal surface

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Science china(physics,Mechanics & Astronomy) 2008年第1期51卷 82-89页

作者： ZHANG XiaoAn 1,2.,XIAO GuoQing 1 ,YANG ZhiHu 1 ,CHEN XiMeng 3 ,ZHAO YongTao 1 , LI FuLi 4 ,WANG Li 1,2.,CUI Ying 3 ,ZHANG HongQiang 3 &ZHAN WenLong 1 1Institute of Modern physics,Chinese Academy of Sciences,Lanzhou 730000,china 2.2. of physics,xianyang normal university,xianyang 712000,china 3{2. of Modern physics,Lanzhou university,Lanzhou 730000,china 4{2. of Applied physics,Xi’an Jiaotong university,Xi’an 710049,china Institute of Modern physics Chinese Academy of Sciences Lanzhou China department of physics Xianyang Normal University Xianyang China department of Modern physics Lanzhou University Lanzhou China department of Applied physics Xi’an Jiaotong University China

Using the slow highly charged ions 12. Xe q+ (q=2.,2.,2.;initial kinetic T0≤4.65 keV/a.u.)to impact Au surface,the Au atomic Mαcharacteristic X-ray spectrum is *** result shows that as long as the charge state of projectile is high enough,the heavy atomic characteristic X-ray can be effectively excited even though the incident beam is very weak(nA magnitude),and the X-ray yield per ion is in the order of 10-8and increases with the kinetic energy and potential energy of *** measuring the Au Mα-X-ray spectra,Au atomic N-level lifetime is estimated at about 1.33×10-18s based on Heisenberg uncertainty relation.

关键词： slow highly charged ions characteristic X-ray level lifetime

X-ray spectra induced by slow highly charged Ar^(q+) ions in collision with Nb surface

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Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1463-1469页

作者： YANG ZhiHu1, CUI Ying2. CHEN XiMeng2. SONG ZhangYong1, SHAO JianXiong2. RUAN FangFang1, ZHANG HongQiang2. DU Juan2. LIU YuWen2. GAO ZhiMing2. ZHANG XiaoAn3, ZHU KeXin1, YU DeYang1 & CAI XiaoHong1 1 Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 730000, china 2.{2. of Modern physics, Lanzhou university, Lanzhou 730000, china 3 {2. of physics, xianyang normal College, xianyang 712000, china Institute of Modern physics Chinese Academy of Sciences Lanzhou China department of Modern physics Lanzhou University Lanzhou China department of physics Xianyang Normal College Xianyang China

The X-ray spectra of Nb surface induced by Arq+ (q =16,17) ions with the energy range from 10 to 2. keV/q were studied by the optical spectrum technology. The experimental results indicate that the multi-electron excitation occurred as a highly charged Ar16+ ion was neutralized below the metal surface. The K shell electron of Ar16+ was excited and then de-excited cascadly to emit K X-ray. The intensity of the X-ray emitted from K shell of the hollow Ar atom decreased with the increase of projectile kinetic energy. The intensity of the X-ray emitted from L shell of the target atom Nb increased with the increase of projectile kinetic energy. The X-ray yield of Ar17+ is three magnitude orders larger than that of Ar16+.

关键词： highly charged ion hollow atom multi-electron X-ray

The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1 & LIN Shenglu2.1. School of physics and Electronic Engineering, Yantai normal {2., Yantai 2.402., china 2. department of physics, Shandong normal {2., Jinan 2.0014, china School of physics and Electronic Engineering Yantai Normal University Yantai China department of physics Shandong Normal University Jinan China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2.1 department of physics,{2. university of Petroleum, Dongying 2.7061,{2. 2.department of physics, Beijing normal university, Beijing 100875,{2. department of physics China University of Petroleum Dongying China department of physics Beijing Normal University Beijing China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

Superconductivity of small metal grains

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2.& ZHU Shunquan1,3 1. department of physics, Shanghai {2. university, Shanghai 2.02.4, china 2. department of physics, Southwest {2. university, Chongqing 400715, china 3. department of Computer and Electric Technology, Shanghai Business School, Shanghai 2.1400, china department of physics Shanghai Normal University Shanghai China department of physics Southwest Normal University Chongqing China department of Computer and Electric Technology Shanghai Business School Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Non-universal Gauge Bosons Z'and the Process e~+e~- →f

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Communications in Theoretical physics 2004年第3期41卷 419-424页

作者： YUE Chong-Xing~1 WANG Shun-Zhi~2.1 department of physics,Liaoning {2. university,Dalian 11602.,china 2.College of physics and Information Engineering,Henan {2. university,Xinxiang 453002.china department of physics Liaoning Normal University Dalian 116029 College of physics and Information Engineering Henan Normal University Xinxiang 453002

Introduetion Altl、ough the standard model(SM)that bases on thega、lge gro、ip SU:(2.xU(1)has been sueeessful in de-seribing the Physies of eleetroweak interaetions,the meeh-anisn,of the eleetroweak symmetry breaking(... 详细信息

关键词： non-universal gauge bosons cross section TC2.models

Different-Periodic Travelling Wave Solutions for Nonlinear Equations

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Communications in Theoretical physics 2004年第4期41卷 481-486页

作者： YE Li-Jun~1 LIN Ji~(1,2.1 department of physics,Zhejiang {2. university,Jinhua 32.004,china2.physics department,Shanghai Jiao Tong university,Shanghai 2.0030,china department of physics Zhejiang Normal University Jinhua 321004 China physics department Shanghai Jiao Tong University Shanghai 200030 China

Using Jacobi elliptic function linear superposition approach for the(1+1)-dimensional Caudrey-Dodd-Gibbon-Sawada-Kotera(CDGSK)equation and the(2.1)-dimensional Nizhnik-Novikov-Veselov(NNV)equation,many new periodic travelling wave solutions with different periods and velocities are obtained based on the knownperiodic *** procedure is crucially dependent on a sequence of cyclic identities involving Jacobi ellipticfunctions sn(ξ,m),cn(ξ,m),and dn(ξ,m).

关键词： linear superposition nonlinear equation travelling wave solution

The kink-soliton and antikink-soliton in quasi-one-dimensional nonlinear monoatomic lattice

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Science china(physics,Mechanics & Astronomy) 2005年第2期48卷 150-157页

作者： XU Quan1 & TIAN Qiang2.1. Scientific and Technological Office, Daqing Teacher College, Daqing 163712. china 2. department of physics , Beijing {2. university, Beijing 100875, china Scientific and Technological Office Daqing Teacher College Daqing China department of physics Beijing Normal University Beijing China

The quasi-one-dimensional nonlinear monoatomic lattice is analyzed. The kink-soliton and antikink-soliton are presented. When the interaction of the lattice is strong in the x-direction and weak in the y-direction, the two-dimensional (2.) lattice changes to a quasi-one-dimensional lattice. Taking nearest-neighbor interaction into account, the vibration equation can be transformed into the KPI, KPII and MKP equation. Considering the cubic nonlinear potential of the vibration in the lattice, the kink-soliton solution is presented. Considering the quartic nonlinear potential and the cubic interaction potential, the kink-soliton and antikink-soliton solutions are presented.

关键词： two-dimensional nonlinear lattice, quasi-one-dimensional nonlinear lattice, kink-soliton, antikink-soliton.