Asymmetric formation of positronium continuum states following positron-impact ionization of H2

被引:34
作者
Berakdar, J [1 ]
机构
[1] Max Planck Inst Microstruct Phys, D-06120 Halle, Germany
关键词
D O I
10.1103/PhysRevLett.81.1393
中图分类号
O4 [物理学];
学科分类号
0702 ;
摘要
The fully differential cross section for the positron- and electron-impact ionization of H-2 is calculated. For positron impact the results are contrasted against a recent experiment which evidently shows the influence of the electron capture to a low-lying positronium continuum state. From a detailed analysis it is deduced that the capture probability is dependent on the orientation of the electron-positron relative momentum vector with respect to the residual ion. Within the used model, this asymmetric positronium formation is traced back to the distortion of the positron motion by the two-center potential formed by the residual ion and the secondary electron.
引用
收藏
页码:1393 / 1396
页数:4
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