原子核对光电离截面的影响  

Influences of nucleus on atomic photoionization cross section

作　　者：刘晓斌[1] 师应龙[1] 邢永忠[1] 路飞平[1] 李向兵 王玉平 桑萃萃 LIU Xiao-Bin;SHI Ying-Long;XING Yong-Zhong;LU Fei-Ping;LI Xiang-Bing;WANG Yu-Ping;SANG Cui-Cui(Department of Physics,Tianshui Normal University,Tianshui 741001,China;College of Science,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]天水师范学院物理系,天水741001 [2]兰州理工大学理学院,兰州730050

出　　处：《原子与分子物理学报》2019年第2期258-262,共5页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(11764035;11464040;11665019)

摘　　要：利用Dirac-Slater相对论平均自洽场理论,研究了不同原子体系光电离截面在不同核模型下的差异.考虑原子核大小时,核的尺寸效应使电子所感受到的有效核电荷减小,并进而影响到电子的概率分布及光电离截面等;对没有考虑原子核大小的点模型,由于不存在核的尺寸效应,出射光电子的波函数有较大相移,从而有可能出现Cooper极小.当入射光子的能量远大于相关电子的电离能时,不同核模型下电子束缚能及平均半径等的差异将相对减小,从而使光电离截面随入射光子能量的变化趋于一致.Based on Dirac-Slater relativistic average self-consistent field, the difference of photoionization cross sections within different nuclear models for different atomic systems have been studied systemically. The calculated results indicate that the effective nuclear charge of electron is decreased when the nuclear finite-size effects is taken into account. Cooper minimum may be occured within nuclear point model, it can be understood by considering the larger phase shift of outgoing photoelectron wave function after the atom absorbs one photon. If the energy of incident photon greatly exceeds the electronic photoionization threshold, the differences of bounding energy and the average radii from nucleus within different nuclear models are decreased oppositely, and the variation of photoionization cross sections with photon energy will turn to consistent.

关 键 词：相对论自洽场 核模型 光电离 尺寸效应 

分 类 号：O562.[理学—原子与分子物理]