Li^+低能(e,2e)反应角分布

ANGULAR DISTRIBUTIONS IN THE LOW ENERGY (e,2e) REACTION OF Li +

利用修正的ＢＢＫ理论，考虑入射道的库仑相互作用及出射电子的交换对称性，在共面等能分享垂直角度碰撞几何中，分别计算了能量为７９６，１０５６，２２７６和３７５６ｅＶ的入射电子碰撞Ｌｉ＋（１ｓ２）（ｅ，２ｅ）反应三重微分截面（ＴＤＣＳ）．结果表明：在接近阈能的碰撞中，两出射电子连线平行于入射电子方向时，ＴＤＣＳ最大；两出射电子连线垂直于入射电子方向时，ＴＤＣＳ最小；入射电子能量达５倍的电离阈能时，主要为单次双体碰撞。

Abstract ? Based on the BBK theory,triple differential cross sections (TDCS) have been calculated for ionization of Li + (1s 2) by electron impact.A coplanar,equal energy,fixed relative angle kinematics is chosen and the particular case where the scattered and ionized electrons emerge perpendicular to each other is emphasized The incoming electron state is considered by a Coulomb wave from the long range attraction between the incident electron and the screened ionic nucleus or approximated by a plane wave.It is shown that the maximum probability for emission near threshold is a configuration in which the interelectronic vector is aligned along the beam direction and the minimum probability when this vector is perpendicular to the beam,and that the initial channel Coulomb field play a major role in determining the TDCS at near threshold energy. 