A theoretical study on final channel screening and exchange effects in large energy loss geometry
大能量损失几何条件下末态屏蔽效应和交换效应的理论研究

The triple differential cross sections for electron impact ionization of helium in the special geometry of coplanar large energy loss are calculated by using the BBK model and the modified BBK model. The calculated results are compared with the experimental results of Catoire and the present experimental results of Stevenson. The previous theoretical deduction is proved and the exchange effects are analyzed and discussed.