Cusp-electron production in collisions of open-shell He-like oxygen ions with atomic targets

NANOS, S.; ESPONDA, N. J.; HILLENBRAND, P.-M.; BINISKOS, A.; LAOUTARIS, A.; QUINTO, M. A.; PETRIDIS, N.; MENZ, E.; ZOUROS, T. J. M.; STÖHLKER, TH.; RIVAROLA, R. D.; MONTI, J. M.; BENIS, E. P.

Physical Review A

American Physical Society

Año: 2023 vol. 107

2469-9926

We report on double differential cross sections of cusp electrons obtained in MeV/u collisions of open-shellHe-like oxygen ions with helium. We use zero-degree electron spectroscopy and our double measurement tech-nique, involving O6+ (1s2 ) ground-state and O6+ (1s2, 1s2s) mixed-state beams, to extract the cusp contributionfrom only the excited O6+ (1s2s) beam. Theoretical calculations based on the continuum distorted wave eikonalinitial state are in very good agreement with the measurements. The roles of the processes of electron captureto the continuum, electron loss to the continuum, and electron loss to the continuum with simultaneous targetionization, which contribute to the cusp peak, are discussed in detail.