X-ray emission in charge-exchange ion-atom and ion-molecule collisions

Charge exchange between highly-charged ions in solar winds and cometary neutrals is the primary process in many observed radiation phenomena in astrophysical environments. The present work examines this process using the two-center basis generator method within the independent electron model. We consider single capture in C$^{6+}$-He collisions from low to intermediate impact energies and benchmark our results with measurements by Defay \textit{et al}. [1,2]. We also consider single and multiple capture in O$^{6+}$-Ar collisions, where impact energies more closely resemble solar wind speeds (approximately from 1.17 to 2.33 keV/u). These results are compared with measurements and calculations by Machacek \textit{et al}. [3]. An outlook on collision-induced radiative processes involving ion-molecule collision systems will be given as well. [1] X. Defay \textit{et al.}, Phys. Rev. A \textbf{88}, 052702 (2013). [2] A.C.K. Leung and T. Kirchner, Phys. Rev. A \textbf{93}, 052710 (2016). [3] J.R. Machacek \textit{et al.}, Astrophys. J. \textbf{809}, 75 (2015).