Effect of local toroidal flow on double-tearing modes in cylindrical geometry
作者：
Zhang, Ruibo;Lu, Xingqiang* ;Guo, Wei;Yin, Chenyan;Gong, Xueyu
期刊：
CONTRIBUTIONS TO PLASMA PHYSICS ,2020年60(9):e202000026- ISSN：0863-1042
通讯作者：
Lu, Xingqiang
作者机构：
[Lu, Xingqiang; Yin, Chenyan; Zhang, Ruibo; Gong, Xueyu] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Zhang, Ruibo] Chinese Acad Sci, Inst Plasma Phys, Hefei, Peoples R China.;[Guo, Wei] Univ South China, Sch Elect Engn, Hengyang, Peoples R China.
通讯机构：
[Lu, Xingqiang] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
double-tearing modes;local toroidal plasma flows;MHD
摘要：
The effect of local toroidal flow (LTF) on double-tearing modes (DTMs) is investigated in cylindrical geometry using the reduced magnetohydrodynamics (RMHD) model. The results indicate that the LTF between the two rational surfaces is the dominant suppression effect on DTMs. The suppression effect is enhanced with the flow width increasing, and the DTMs become more stable with the increase of the shear of the LTF between the two rational surfaces. So, in the reversed shear magnetic field configuration, the local flow is driven between the two rational surfaces, which can effectively suppress the development of DTMs and maintain the high-performance state.
语种：
英文
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First experimental results of intrinsic torque on EAST
作者：
Wang, Xunyu;Lyu, Bo* ;Lu, Xingqiang* ;Li, Yingying;Solomon, W. M.;...
期刊：
等离子体科学与技术：英文版 ,2020年22(6):065104 ISSN：1009-0630
通讯作者：
Lu, Xingqiang;Lyu, Bo
作者机构：
[Gong, Xueyu; He, Liang; Yang, Jin; Lu, Xingqiang; Wang, Xunyu] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Bin, Bin; Li, Yingying; Wan, Shunkuan; Chen, Jun; Fu, Jia; Wang, Fudi; Hao, Baolong; He, Liang; Wan, Baonian; Lyu, Bo; Zhang, Hongming; Yang, Jin; Li, Yichao; Wang, Xunyu] Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Peoples R China.;[Solomon, W. M.] Gen Atom, San Diego, CA 92186 USA.;[Chen, Jun; Ye, Minyou] Univ Sci & Technol China, Dept Engn & Appl Phys, Hefei 230026, Peoples R China.
通讯机构：
[Lu, Xingqiang] U;[Lyu, Bo] C;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Peoples R China.
关键词：
intrinsic torque;balanced injection;momentum transport
摘要：
Direct measurements of the intrinsic torque profile in L-mode plasmas on the EAST tokamak have been performed using the balanced neutral beam injection. Co- and counter-current neutral beams are modulated to balance the intrinsic and externally injected torques, which result in the rotation profile close to zero and flat. The experimental results show that the intrinsic torque derived from momentum balance equations is found to be in the co-current direction, peaked in the plasma edge and negligibly small in the core.
语种：
英文
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Influence of stationary driven helical current on the m=2/n=1 resistive tearing mode
作者：
Yuan, Yun;LU, Xingqiang* ;Dong, Jiaqi;He, Zhixiong;Zhang, Ruibo;...
期刊：
等离子体科学与技术：英文版 ,2019年21(5):055101 ISSN：1009-0630
通讯作者：
LU, Xingqiang
作者机构：
[LU, Xingqiang; Yuan, Yun; Gong, Xueyu] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Chen, Shijia; Yuan, Yun] Natl Univ Def Technol, Coll Sci, Changsha 410073, Hunan, Peoples R China.;[Dong, Jiaqi] Ctr Fus Sci, Southwestern Inst Phys, Chengdu 610041, Sichuan, Peoples R China.;[He, Zhixiong] Fujian Univ Technol, Sch Math & Phys, Fuzhou 350108, Fujian, Peoples R China.;[Zhang, Ruibo] Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Anhui, Peoples R China.
通讯机构：
[LU, Xingqiang] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
tearing modes;helical current;MHD instability
摘要：
The influence of stationary driven helical current on tearing mode instability in the m = 2/n = 1 rational surface is explored numerically using resistive magnetohydrodynamic simulation in cylindrical geometry. The results indicate that the flip instabilities result from the sustained injection of the sufficiently strong helical current driven in the island O-point. The driven helical current induces high order harmonics of instabilities due to the delay of suppressing timing and the increase of its current intensity. With the appropriate current density values, the development of the perturbed kinetic energy can be limited and the occurrence of the flip instabilities can be delayed for a long time. The radial deviation of the current deposition can lead to poor inhibition effect, and the effect of current bias on the boundary is greater than that on the axis. © 2019 Hefei Institutes of Physical Science, Chinese Academy of Sciences and IOP Publishing.
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英文
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基于工程教育专业认证的的核类专业新工科建设探索
作者：
路兴强
期刊：
教育现代化 ,2018年5(42):75-76 ISSN：2095-8420
作者机构：
南华大学 核科学技术学院,湖南 衡阳,421001;[路兴强] 南华大学
关键词：
工程教育专业认证;新工科;核类专业
摘要：
本文基于工程教育专业认证理念对核类专业新工科建设进行实践研究.依据国家战略和产业发展,通过研究核类专业培养目标、毕业要求、课程教学的关系,建立专业动态调整机制和专业培养模式.本研究对深化高等工程教育改革,培养大学生创新能力有重要意义.
语种：
中文
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Stabilizing effect of helical current drive on tearing modes
作者：
Yuan, Y.;Lu, X. Q.* ;Dong, J. Q.;Gong, X. Y.;Zhang, R. B.
期刊：
PHYSICS OF PLASMAS ,2018年25(1):012510 ISSN：1070-664X
通讯作者：
Lu, X. Q.
作者机构：
[Yuan, Y.; Gong, X. Y.; Lu, X. Q.] Univ South China, Sch Nucl & Technol, Hengyang 421001, Peoples R China.;[Dong, J. Q.] Southwestern Inst Phys, Chengdu 610041, Sichuan, Peoples R China.;[Zhang, R. B.] Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Anhui, Peoples R China.
通讯机构：
[Lu, X. Q.] U;Univ South China, Sch Nucl & Technol, Hengyang 421001, Peoples R China.
关键词：
plasma magnetohydrodynamics;plasma simulation;plasma transport processes;tearing instability
摘要：
The effect of helical driven current on the m = 2/n = 1 tearing mode is studied numerically in a cylindrical geometry using the method of reduced magneto-hydro-dynamic simulation. The results show that the local persistent helical current drive from the beginning time can be applied to control the tearing modes, and will cause a rebound effect called flip instability when the driven current reaches a certain value. The current intensity threshold value for the occurrence of flip instability is about 0.00087I0. The method of controlling the development of tearing mode with comparative economy is given. If the local helical driven current is discontinuous, the magnetic island can be controlled within a certain range, and then, the tearing modes stop growing; thus, the flip instability can be avoided. We also find that the flip instability will become impatient with delay injection of the driven current because the high order harmonics have been developed in the original O-point. The tearing mode instability can be controlled by using the electron cyclotron current drive to reduce the gradient of the current intensity on the rational surfaces. © 2018 Author(s).
语种：
英文
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On current drive by Ohkawa mechanism of electron cyclotron wave in large inverse aspect ratio tokamaks
作者：
Zheng, Pingwei;Gong, Xueyu* ;Lu, Xingqiang;He, Lihua;Cao, Jingjia;...
期刊：
Nuclear Fusion ,2018年58(3):036010 ISSN：0029-5515
通讯作者：
Gong, Xueyu
作者机构：
[Deng, Sheng; Zheng, Pingwei; Lu, Xingqiang; He, Lihua; Huang, Qianhong; Cao, Jingjia; Gong, Xueyu] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Gong, Xueyu] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
关键词：
Cyclotron radiation;Cyclotrons;Efficiency;Electron beams;Electrons;Inverse problems;Magnetohydrodynamics;Plasma waves;Alternative current;Current drive efficiencies;Current drives;Electron cyclotron waves;Inverse aspect ratio;MHD instabilities;Off-axis;Potential capability;Aspect ratio
摘要：
A localized and efficient current drive method in the outer-half region of the tokamak with a large inverse aspect ratio is proposed via the Ohkawa mechanism of electron cyclotron (EC) waves. Further off-axis Ohkawa current drive (OKCD) via EC waves was investigated in high electron beta β e HL-2M-like tokamaks with a large inverse aspect ratio, and in EAST-like tokamaks with a low inverse aspect ratio. OKCD can be driven efficiently, and the driven current profile is spatially localized in the radial region, ranging from 0.62 to 0.85, where the large fraction of trapped electrons provides an excellent advantage for OKCD. Furthermore, the current drive efficiency increases with an increase in minor radius, and then drops when the minor radius beyond a certain value. The effect of trapped electrons greatly enhances the current driving capability of the OKCD mechanism. The highest current drive efficiency can reach 0.183 by adjusting the steering mirror to change the toroidal and poloidal incident angle, and the total driven current by OKCD can reach 20-32 kA MW-1 in HL-2M-like tokamaks. The current drive is less efficient for the EAST-like scenario due to the lower inverse aspect ratio. The results show that OKCD may be a valuable alternative current drive method in large inverse aspect ratio tokamaks, and the potential capabilities of OKCD can be used to suppress some important magnetohydrodynamics instabilities in the far off-axis region. © 2018 IAEA, Vienna.
语种：
英文
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Modeling of the control of the driven current profile in ICRF MCCD on EAST plasma
作者：
Yin, L.;Yang, C.;Gong, X. Y.* ;Lu, X. Q.;Cao, J. J.;...
期刊：
AIP Advances ,2018年8(5):055315 ISSN：2158-3226
通讯作者：
Gong, X. Y.
作者机构：
[Du, D.; Chen, Y.; Gong, X. Y.; Yin, L.] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.;[Chen, Y.; Cao, J. J.; Wu, Z. Y.; Yin, L.; Lu, X. Q.] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Yang, C.] Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Anhui, Peoples R China.
通讯机构：
[Gong, X. Y.] U;Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.
摘要：
Control of the current profile is a crucial issue for improved confinement and the inhibition of instability in advanced tokamak operation. Using typical discharge data for the Experimental Advanced Superconducting Tokamak, numerical simulations of driven-current profile control in mode conversion current drive (MCCD) in the ion cyclotron range of frequencies were performed employing a full-wave method and Ehst-Karney efficiency formula. Results indicate that the driven current profile in MCCD can be effectively modified by shifting the mode conversion layer. The peak of the driven current can be located at an aimed position in the normalized minor radius range (-0.60≤r/a≤0) by changing the radiofrequency and the minority-ion concentration. The efficiency of the off-axis MCCD can reach 233 kA/MW through optimization, and the mode converted ion cyclotron wave plays an important role in such scenarios. The effects of electron temperature and plasma density on the driven current profile are also investigated. © 2018 Author(s).
语种：
英文
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Comparative study of Fisch-Boozer and Ohkawa current drive mechanisms for electron cyclotron waves
作者：
Zheng, P. W.;Gong, X. Y.* ;Lu, X. Q.;Cao, J. J.;He, L. H.;...
期刊：
PHYSICS OF PLASMAS ,2018年25(7):072501 ISSN：1070-664X
通讯作者：
Gong, X. Y.
作者机构：
[Huang, Q. H.; Deng, S.; Zheng, P. W.; He, L. H.; Cao, J. J.; Lin, J. F.; Gong, X. Y.; Lu, X. Q.] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.;[Zheng, P. W.] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Zhong, Y. J.] Univ South China, Sch Math & Phys, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Gong, X. Y.] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
关键词：
plasma radiofrequency heating;plasma simulation;plasma toroidal confinement;tearing instability;Tokamak devices
摘要：
Localized current drive by electron cyclotron (EC) waves is of significant importance in the outer half region of tokamak plasmas. Using the coupled GENRAY/CQL3D suite codes, a systematic comparative study between Ohkawa current drive (OKCD) and electron cyclotron current drive (ECCD) is performed. The results show that OKCD has more advantages than ECCD for far off-axis localized current drive in tokamaks with large inverse aspect ratios, while ECCD is more efficient than OKCD in tokamaks with low inverse aspect ratios. The results of local current driving on the q = 2 rational surface show that both OKCD and ECCD are effective for control of the m = 2/n = 1 tearing mode or neoclassical tearing mode (NTM). It seems that efficient Ohkawa current can be driven in a specific far off-axis radial position as long as the local inverse aspect ratio is large enough. The effect of collisionality imposes a significant impact on OKCD and results in reduction of the net current driven by unit EC power. The dimensionless current drive efficiency of OKCD increases with increasing electron beta β<inf>e</inf>in a medium range. The results further confirm that OKCD can be a valuable alternative localized current drive method to replace ECCD in large inverse aspect ratio tokamaks or in the radial position where the local inverse aspect ratio is large enough.<br/> ©2018 Author(s).
语种：
英文
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飞秒激光脉宽对非绝热耦合分子波包运动的影响研究
作者：
郭玮;王怡;李月华;路兴强
期刊：
原子与分子物理学报 ,2018年35(3):455-460 ISSN：1000-0364
作者机构：
南华大学 电气工程学院,衡阳 421001;中国科学院大连化学物理研究所分子反应动力学国家重点实验室,大连116023;南华大学 电气工程学院,衡阳,421001;南华大学 核科学技术学院,衡阳,421001;[郭玮; 路兴强; 李月华; 王怡] 南华大学
关键词：
分子物理学;波包运动;含时波包法;非绝热耦合NaI分子;态布居;激发概率;解离概率
摘要：
利用含时波包法研究了强飞秒泵浦-探测激光场中激光脉宽对非绝热耦合NaI分子波包运动的影响.发现波包的振荡周期随脉宽增长而增大,而振荡幅度随脉宽增长而减小.非绝热效应引起的波包在交叉区域的分裂情况影响各态布居.脉宽增长,NaI分子的激发概率增大,而解离概率减小.研究表明调节激光场脉宽可实现对波包运动的控制从而控制态布居的选择性分布.研究结果可以为实验上实现分子的光控制以及量子调控过程提供一定的参考.
语种：
中文
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局部驱动螺旋电流对撕裂模不稳定性的影响
作者：
袁赟;路兴强;龚学余;尹陈艳;陈诗佳
期刊：
原子能科学技术 ,2018年52(2):221-226 ISSN：1000-6931
通讯作者：
Lu, Xingqiang(luxingqiang@163.com)
作者机构：
[袁赟; 路兴强; 龚学余; 尹陈艳; 陈诗佳] School of Nuclear Science and Technology, University of South China, Hengyang;421001, China;[袁赟; 路兴强; 龚学余; 尹陈艳; 陈诗佳] 421001, China
通讯机构：
School of Nuclear Science and Technology, University of South China, Hengyang, China
会议名称：
中国原子能科学研究院第31届“五四”青年学术报告会
会议时间：
2017-04-27
会议地点：
北京
会议论文集名称：
中国原子能科学研究院第31届“五四”青年学术报告会论文集
关键词：
局部驱动螺旋电流;撕裂模不稳定性;磁岛宽度
摘要：
采用约化磁流体力学模拟方法,在托卡马克大环径比近似情况下,研究了局部驱动螺旋电流对撕裂模不稳定性的影响,分析了螺旋电流强度、螺旋电流径向沉积宽度以及螺旋电流加入时刻对m=2/n=1经典撕裂模发展过程的影响。研究结果表明:螺旋电流强度的增大和沉积宽度的变窄都会更有效地抑制经典撕裂模的发展,但过强的螺旋电流强度或较小的螺旋电流沉积宽度会引起翻转不稳定性;随着螺旋电流在经典撕裂模发展过程中加入时刻的推迟,其对撕裂模不稳定性的控制效果会越来越差。
语种：
中文
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飞秒激光脉宽对三态阶跃型分子波包运动的影响研究
作者：
郭玮;常志强;王怡;路兴强
期刊：
原子与分子物理学报 ,2017年34(5):908-914 ISSN：1000-0364
作者机构：
南华大学电气工程学院,衡阳421001;中国科学院大连化学物理研究所分子反应动力学国家重点实验室,大连116023;南华大学电气工程学院,衡阳,421001;南华大学核科学技术学院,衡阳,421001;[郭玮; 路兴强; 常志强; 王怡] 南华大学
关键词：
分子物理学;波包运动;含时波包法;三态阶跃型K2分子;光电子能谱;态布居数
摘要：
用含时波包法研究了三态阶跃型K2分子在强飞秒泵浦-探测激光场中脉宽对波包动力学过程的影响.研究表明激光场强较弱或者脉宽较短都可能不出现Autler-Townes分裂.波包的振荡周期随脉宽增长而增大,而振荡幅度随脉宽增长而减小.脉宽影响Rabi振荡,而Rabi振荡的变化又导致了基态和激发态布居数周期性变化.首次量化了脉宽对激发态布居数的影响,表明变化频率随着泵浦场强的增强而增大.研究表明调节激光脉宽可实现对态布居数的选择性分布,可以为实验上实现分子的光控制提供重要参考.
语种：
中文
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Stabilizing effect of helical current drive on tearing mode
作者：
Xingqiang Lu;Yuan Yun;Xueyu Gong
作者机构：
[Xingqiang Lu; Yuan Yun; Xueyu Gong] School of Nuclear Science and Technology,University of South China
会议名称：
The 2nd International Conference on Matter and Radiation at Extremes(ICMRE 2017)
会议时间：
2017-06-26
会议地点：
中国北京
摘要：
The effect of helical driven current on the m=2/n=l tearing mode are studied numerically in cylindrical geometry using the method of reduced magneto-hydro-dynamic(RMHD) simulation.The results show tha
语种：
英文
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ICRF fast wave current drive and mode conversion current drive in EAST tokamak
作者：
Yin, L.;Yang, C.;Gong, X. Y.* ;Lu, X. Q.;Du, D.;...
期刊：
PHYSICS OF PLASMAS ,2017年24(10):102502 ISSN：1070-664X
通讯作者：
Gong, X. Y.
作者机构：
[Du, D.; Chen, Y.; Yin, L.] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.;[Chen, Y.; Gong, X. Y.; Yin, L.; Lu, X. Q.] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Yang, C.] Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Anhui, Peoples R China.
通讯机构：
[Gong, X. Y.] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
plasma radiofrequency heating;plasma toroidal confinement;Tokamak devices
摘要：
Fast wave in the ion-cyclotron resonance frequency (ICRF) range is a promising candidate for non-inductive current drive (CD), which is essential for long pulse and high performance operation of tokamaks. A numerical study on the ICRF fast wave current drive (FWCD) and mode-conversion current drive (MCCD) in the Experimental Advanced Superconducting Tokamak (EAST) is carried out by means of the coupled full wave and Ehst-Karney parameterization methods. The results show that FWCD efficiency is notable in two frequency regimes, i.e., integral >= 85 MHz and integral = 50-65 MHz, where ion cyclotron absorption is effectively avoided, and the maximum on-axis driven current per unit power can reach 120 kA/MW. The sensitivity of the CD efficiency to the minority ion concentration is confirmed, owing to fast wave mode conversion, and the peak MCCD efficiency is reached for 22% minority-ion concentration. The effects of the wave-launch position and the toroidal wavenumber on the efficiency of current drive are also investigated. Published by AIP Publishing.
语种：
英文
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射频波电流驱动抑制双撕裂模不稳定性研究
作者：
陈诗佳;龚学余;李新霞;何志雄;路兴强
期刊：
原子能科学技术 ,2017年51(4):597-602 ISSN：1000-6931
通讯作者：
Li, Xin-Xia(leexinxia@126.com)
作者机构：
[李新霞; 路兴强; 陈诗佳; 龚学余] School of Nuclear Science and Technology, University of South China, Hengyang, 421001, China;[何志雄] Southwestern Institute of Physics, Chengdu, 610041, China
通讯机构：
School of Nuclear Science and Technology, University of South China, Hengyang, China
关键词：
托卡马克;磁流体;双撕裂模不稳定性
摘要：
采用不可压缩磁流体模型,在圆柱位形下研究了射频波电流驱动对双撕裂模不稳定性的影响。结果表明,托卡马克装置中沉积在有理面上的同向驱动电流能有效减缓3/1双撕裂模的发展。电流驱动幅值约占等离子体电流初始值的4%、驱动电流沉积宽度约为小环半径的7%时,抑制效果较好。此外,研究表明,在双撕裂模进入快速增长阶段前加入外部驱动电流,才能有效抑制撕裂模的磁爆发。
语种：
中文
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The Delay Time Dependence of the Photoelectron Spectra and State Populations of Three-Level Ladder K-2 Molecule(1)
作者：
Guo, Wei;Lu, Xingqiang* ;Wang, Xinlin
期刊：
Russian Journal of Physical Chemistry A ,2017年91(2):366-372 ISSN：0036-0244
通讯作者：
Lu, Xingqiang
作者机构：
[Guo, Wei; Wang, Xinlin] Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.;[Guo, Wei] Dalian Inst Chem Phys, State Key Lab Mol React Dynam, Dalian 116023, Peoples R China.;[Lu, Xingqiang] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
通讯机构：
[Lu, Xingqiang] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
关键词：
photoelectron spectra;state populations;time-dependent wave packet approach;three-level ladder K2 molecule
摘要：
The delay time dependence of photoelectron spectra and state populations of three-level ladder K2 molecule is investigated by pump-probe pulses via time-dependent wave packet approach. The periodical motion of the wave packet with oscillating period 500 fs results in the periodical variation of photoelectron spectra. The photoelectron spectra show Autler-Townes double splitting at zero delay time, and no splitting at positive delay time. The periodical change of state populations with delay time can be ascribed to the coupling effect between the two pulses. It is found that the selectivity of the state populations may be attained by regulating the delay time. The results can provide some important basis for realizing the optical control of molecules experimentally.
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英文
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低频Alfven波多波相干加热粒子模拟
作者：
李芙屹;向东;龚学余;路兴强
期刊：
计算物理 ,2016年33(4):441-446 ISSN：1001-246X
通讯作者：
Gong, X.
作者机构：
[李芙屹; 向东; 龚学余; 路兴强] 南华大学核科学技术学院, 湖南, 衡阳, 421001
通讯机构：
School of Nuclear Science and Technolodge, University of South China, Hengyang, China
关键词：
粒子模拟;低频Alfven波;多波相干加热
摘要：
采用粒子模拟方法,考察多支沿背景磁场方向传播的低频Alfven波对磁化等离子体的加热过程,研究不同频率的多支低频Alfven波相干加热.结果表明可以通过调整波的频率比实现对非共振加热过程和随机加热过程这两个阶段的强化.符合相干共振条件的多波加热会强化低频Alfven波对粒子拾取,进而强化非共振加热,明显提高加热效率.在多波加热的过程中,如果多支波之间的频率差足够小,则多波在调制过程中会形成波包.波包的出现标志着粒子各向异性的强化,从而提升随机加热效率.
语种：
中文
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A study on interactions between ions and polarized Alfven waves below cyclotron resonance frequency
作者：
Lu, Xing-Qiang;Tang, Wei-Zhong;Guo, Wei* ;Gong, Xue-Yu
期刊：
PHYSICS OF PLASMAS ,2016年23(12):122114 ISSN：1070-664X
通讯作者：
Guo, Wei
作者机构：
[Lu, Xing-Qiang; Gong, Xue-Yu; Tang, Wei-Zhong] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Guo, Wei] Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Guo, Wei] U;Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.
关键词：
plasma Alfven waves;plasma collision processes;plasma heating;plasma simulation
摘要：
Ion heating by different polarized Alfvén waves below the cyclotron resonance frequency is studied using test-particle simulation. The results indicate that the interactions between ions and waves are affected by the polarization and frequency of the waves. If the frequency of waves is higher (ω>0.1 Ω<inf>p</inf>), the interactions between ions and left-hand (LH) waves are stronger than right-hand (RH) waves due to the sub-cyclotron resonance. However, with the decrease of the frequency, the interactions between different polarized Alfvén waves and particles tend to be the same. The heating effects of LH waves on ions are better than RH waves at higher frequencies. When the frequency of the waves is lower enough (ω<0.1 Ω<inf>p</inf>), the heating effects of LH waves and RH waves on ions are almost identical. The change of heating efficiency with the polarization and frequency of the waves is consistent with the change of the heating effect. ©2016 Author(s).
语种：
英文
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Field dependence of state populations in pump-probe pulses
作者：
Lu, Xingqiang;Guo, Wei*
期刊：
Optik ,2016年127(13):5200-5203 ISSN：0030-4026
通讯作者：
Guo, Wei
作者机构：
[Lu, Xingqiang] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Guo, Wei] Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.;[Guo, Wei] Dalian Inst Chem Phys, State Key Lab Mol React Dynam, Dalian 116023, Peoples R China.
通讯机构：
[Guo, Wei] U;[Guo, Wei] D;Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.;Dalian Inst Chem Phys, State Key Lab Mol React Dynam, Dalian 116023, Peoples R China.
关键词：
Dissociation;Excited states;Laser excitation;Mechanical waves;Molecules;Probability;Probes;Pumping (laser);Wave packets;Dissociation probability;Femtosecond pump probes;Non-adiabatic effect;Population transfer;Time-dependent wave packet approaches;Optical pumping
摘要：
The effects of pulse width, laser wavelength and laser intensity on the state populations of NaI molecule driven by a pump-probe pulse were studied via employing the time-dependent wave packet approach. Wave packet moves periodically with roundtrip time 1000 fs. That the wave packet bifurcates in the crossing region affects state populations. The excitation probability increases and dissociation probability decreases with increasing pulse width. The excitation probability approaches the maximum at the resonance pump wavelength 318 nm, and the dissociation probability decreases with increasing pump wavelength. The excitation probability increases with increasing pump intensity while the dissociation probability does not vary. The probe wavelength and probe intensity have no effect on state populations. The wave packet motion and selective distribution of state populations, excitation and dissociation of molecule can be achieved by adjusting laser parameters. The results can provide some important basis for realizing quantum manipulation of molecules experimentally. © 2016 Elsevier GmbH. All rights reserved.
语种：
英文
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Behavior of fast earthward flow near the braking region: Hall MHD simulation
作者：
Lu, Xingqiang;Ma, Zhiwei* ;Guo, Wei
期刊：
EPL ,2016年116(2):29001 ISSN：0295-5075
通讯作者：
Ma, Zhiwei
作者机构：
[Lu, Xingqiang] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Ma, Zhiwei] Zhejiang Univ, Inst Fus Theory & Simulat, Hangzhou 310027, Zhejiang, Peoples R China.;[Guo, Wei] Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Ma, Zhiwei] Z;Zhejiang Univ, Inst Fus Theory & Simulat, Hangzhou 310027, Zhejiang, Peoples R China.
摘要：
Behavior of the fast earthward flow near the braking region in the magnetotail during a substorm is investigated using the Hall MHD simulation. The results indicate that the high-speed earthward plasma flow is associated with fast reconnection in the middle tail. The fast flow is mainly confined in the range -1.5R(E) < z < 1.5R(E). In the region of -15R(E) < x < -9R(E), due to intermittent magnetic reconnection, the earthward flow exhibits a fluctuating property, i. e., the flow is localized in space and is bursty in time. The pile-up of the magnetic flux and plasma in the near-Earth region leads to formation of the fast-flow braking region or dipolarization front. After colliding into the fast-flow braking region, a part of the Earth flow bounces back, and leads to an intermittent tailward flow in the near-Earth magnetotail.
语种：
英文
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Effect of laser pulse width on wave packet motion in femotosecond pump-probe pulses
作者：
Guo, Wei* ;Feng, Xiaojing;Lu, Xingqiang
期刊：
Optik ,2016年127(24):12010-12016 ISSN：0030-4026
通讯作者：
Guo, Wei
作者机构：
[Guo, Wei; Feng, Xiaojing] Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.;[Guo, Wei] Dalian Inst Chem Phys, State Key Lab Mol React Dynam, Dalian 116023, Peoples R China.;[Lu, Xingqiang] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
通讯机构：
[Guo, Wei] U;Univ South China, Sch Elect Engn, Hengyang 421001, Peoples R China.
关键词：
Electronic states;Excited states;Mechanical waves;Photoelectron spectroscopy;Photoelectrons;Photons;Probes;Pumping (laser);Wave packets;Femtosecond pump probes;Photoelectron spectrum;State population;Time-dependent wave packet approaches;Wave-packet motion;Optical pumping
摘要：
The dependence of the wave packet process of three-level ladder K2 molecules on pulse width was investigated via time-dependent wave packet method, and was firstly quantified. There is no Autler-Townes splitting in the photoelectron spectrum with weaker pump intensity or shorter pulse width. The oscillation period of wave packet increases and the oscillation amplitude decreases with increasing pulse width. The pulse width affects Rabi oscillation, which results in the periodical change of the populations of the electronic state. Quantifying its effect on the population of the excited state shows that the change frequency varies with increasing pump intensity. The results illustrates that the needed population in electronic state of interested can be obtained by controlling pulse width, which provide some important basis for light manipulation of molecular processes experimentally. © 2016
语种：
英文
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