Near-threshold electron-impact ionization of calcium atoms

被引:3
作者
Kontros, J. E. [1 ]
Chernyshova, I. V. [1 ]
Shpenik, O. B. [1 ]
机构
[1] Natl Acad Sci Ukraine, Inst Electron Phys, UA-88017 Uzhgorod, Ukraine
关键词
CROSS-SECTIONS; RESONANCE STRUCTURE; EXCITATION; CA; STATES; MULTIPLE; SR; BA;
D O I
10.1134/S0030400X1103012X
中图分类号
O43 [光学];
学科分类号
070207 ; 0803 ;
摘要
The electron-impact ionization of calcium atoms is studied in the near-threshold energy range (from 6.11 to 16 eV). Experiments were performed by the method of intersecting electron and atomic beams with the recording of formed positive calcium ions. The electron beam (Delta E (1/2) = 0.15 eV) was formed using a hypocycloidal electron monochromator. An analysis of the specific features of ionization cross sections revealed a contribution from the excitation and decay of low-lying autoionization atomic states, which converge to the excitation thresholds of the 3d, 4p, and 5s ionic levels, and resonances (long-lived states of negative ions). The specific features of cross sections are identified using the experimental and theoretical data on photoionization (photoabsorption).
引用
收藏
页码:500 / 507
页数:8
相关论文
共 24 条