Single- and double-electron-capture processes occurring in the system of hydrogen ions colliding with alkaline-earth atoms, ${\mathrm{H}}^{+}+\mathrm{Mg}$, are investigated in a broad energy domain ranging from 0.25 to 180 keV. Total and state-selective cross sections are calculated using a two-active-electron semiclassical asymptotic-state close-coupling approach. Our results show the best overall agreement with experimental data, and possible reasons for observed discrepancies are discussed. Comparison of our cross sections with previous theoretical results further demonstrates the importance of electronic correlations between the magnesium valence electrons and the strong couplings between various important channels. Furthermore, our investigations suggest that the oscillatory structures observed in the double-electron-capture cross sections stem from complex coherence effects between double-electron capture, electron transfer to excited states, and transfer-excitation processes.

中文翻译：

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中能H++Mg碰撞中的单电子和双电子捕获

氢离子与碱土原子碰撞系统中发生的单电子和双电子俘获过程， ${\mathrm{H}}^{+}+镁$, 在从 0.25 到 180 keV 的广泛能量域中进行研究。总截面和状态选择性截面是使用两个有源电子半经典渐近态紧密耦合方法计算的。我们的结果显示了与实验数据的最佳整体一致性，并讨论了观察到的差异的可能原因。我们的横截面与之前的理论结果的比较进一步证明了镁价电子之间的电子相关性和各种重要通道之间的强耦合的重要性。此外，我们的研究表明，在双电子捕获截面中观察到的振荡结构源于双电子捕获、电子转移到激发态和转移激发过程之间的复杂相干效应。