Nonrelativistic double photoeffect on K-shell electrons
Nonrelativistic double photoeffect on K-shell electrons
复制标题
K 壳层电子的非相对论双光效应
DOI：
10.1103/physreva.69.032703
复制
发表时间：
2004
影响因子：
2.9
通讯作者：
G. Soff
中科院分区：
文献类型：
--
作者：
A. Mikhailov;I. Mikhailov;A. Moskalev;A. Nefiodov;G. Plunien;G. Soff
我们研究了类氦离子的双k壳电离，它是由能量远小于电子剩余能量的单光子吸收引起的。在近阈值区域，考虑到$1/Z$和$\ensuremath{\alpha}Z$展开的阶数，计算了光离子的微分截面和总截面。对于中等核电荷数$Zg~2，关于参数$1/Z$的QED微扰理论在整个非相对论性区域具有快速收敛性。超出电偶极子近似会导致射出电子相对于入射光子束的角分布出现正向/反向不对称。对一些中性原子的双光离与单光离截面比的理论预测与现有的实验数据进行了比较。
We investigate the double K-shell ionization of heliumlike ions caused by the absorption of a single photon with energies being much smaller than the rest energy of an electron. In the near-threshold region, differential and total cross sections of the process are calculated for light ions, taking into account the leading orders of the $1/Z$ and $\ensuremath{\alpha}Z$ expansions. QED perturbation theory with respect to the parameter $1/Z$ exhibits a fast convergence in the entire nonrelativistic domain for moderate nuclear charge numbers $Zg~2.$ Going beyond the electric dipole approximation leads to a forward/backward asymmetry in the angular distributions for the ejected electrons with respect to the incident photon beam. A comparison of theoretical predictions for the ratio of double-to-single photoionization cross sections with available experimental data for a number of neutral atoms is also presented.