Production of C4+ (2s2p 3,1P) hollow states in collisions of 6-18 MeV C4+ (1s2, 1s2s 3S) mixed-state beams with gas targets

Abstract

Normalized electron yields of the formation of 2s2p ^3,1P states from the metastable states 1s2s ^3,1S and from the ground state 1s²¹S were obtained in 6-18MeV C⁴⁺ collisions with H₂, He, Ne and Ar gas targets. The method of zero-degree Auger projectile spectroscopy was used to detect electrons emitted in the Auger decay C⁴⁺ (2s2p ^3,1P) → C⁵⁺ (1s) + e^-with high resolution. These states are of particular importance in the detailed study of fundamental excitation mechanisms, i.e. electron-nucleus excitation, electron-electron excitation and electron-electron excitation with spin exchange. Currently, the role of the above mechanisms in the production of the 2s2p ^3,1P states is investigated utilizing variable 1s2s ³S metastable fraction beams as a function of collision energy and target species. Our latest results are presented.