Electron-impact excitation and ionization of Rb and Rb⁺ using the Dirac B-Spline R-Matrix method

In the Interatomic Coulomb Electron Capture (ICEC) process [1,2], a species 𝐴 captures a free electron by long-range energy transfer through Coulomb interaction to a bound electron in a neighboring species 𝐵. Recent work involving the ICEC process has further focused on time-resolved descriptions of this process, with one example probing Rubidium-assisted electron capture by a Ba²⁺ cation [3]. To further support such computational and experimental investigations, it is important to have accurate data on electron-impact excitation and ionization of neutral and singly-ionized Rubidium. In this work, we seek to determine electron-impact excitation and ionization cross sections of Rb and Rb⁺ using the Dirac B-Spline atomic R-Matrix suite of codes [4,5]. An initial atomic structure description of Rb²⁺ is generated using DBSR_HF, a B-Spline Dirac-Hartree-Fock program [6]. Bound states of Rb and Rb⁺, and subsequently the cross sections, are determined using the DBSR suite.



[1] K. Gokhberg and L.S. Cederbaum, Phys. Rev. A 82 (2010) 052707

[2] A. Bande et al., J. Phys. B 56 (2023) 232001

[3] A. Molle et al., arXiv:2306.09580 (2023)

[4] O. Zatsarinny and K. Bartschat, Phys. Rev. A 77 (2008) 062701

[5] O. Zatsarinny, https://github.com/zatsaroi

[6] O. Zatsarinny and C. Froese Fischer, Comp. Phys. Commun. 202 (2016) 287-303