State-selective single-electron capture in 30 keV N3+-He collisions

Abstract: The Cold-target recoil-ion momentum spectroscopy (COLTRIMS) has been employed to study the single-electron capture processes in collisions of N3+ ions with He atoms at an impact energy of 30 keV. The relative differential cross sections for the capture to different orbitals of N3+ ions are obtained and are compared with other experiments at low energy. The predictions of the molecular Columbic barrier model have been made. From the longitudinal momentum spectrum of recoil ions, the different electronic configuration was identified and the metastable projectile ions were distinguished. The single electron capture into the N2+ (1s22s22p 2P) state from the ground state N3+ (1s22s2 1S) projectile is the dominant reaction channel. The fraction of the metastable state N3+(2s2p 3P) of the incident projectile beam is about 46%.