Collisional ionization between two Rydberg atoms in relative motion is examined. A classical trajectory Monte Carlo method is used to determine the cross sections associated with Penning ionization. The dependence of the ionization cross section on the magnitude and the direction of orbital angular momentum of the electrons and the direction of the Laplace-Runge-Lenz vector of the electrons is studied. For a given magnitude of angular momentum, there can exist a difference of a factor of up to $\sim 2.5$ in the ionization cross section between the orientations with the highest and the lowest ionization cross section. The case of exchange ionization is examined and its dependence on the magnitude of angular momentum is studied.

中文翻译：

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雷德堡原子的取向对其碰撞电离截面的影响

研究了相对运动下两个里德堡原子之间的碰撞电离。经典轨迹蒙特卡罗方法用于确定与Penning电离相关的横截面。研究了电离截面对电子的轨道角动量的大小和方向以及电子的Laplace-Runge-Lenz矢量的方向的依赖性。对于给定的角动量，可以存在高达$〜2.5$在具有最高和最低电离横截面的取向之间的电离横截面。研究了交换电离的情况，并研究了其对角动量大小的依赖性。