Population distribution subsequent to charge exchange of 29.85keV Ni + on sodium vapor

The population of low-energy metastable states in Ni I subsequent to charge-exchange reactions and cascade decay was studied for 29.85keV Ni ions impinging on a sodium vapor. The charge-exchange cross sections were calculated using a semi-classic time-dependent perturbation theory and redistribution of the population via rapid spontaneous decays was simulated. Collinear laser spectroscopy experiments were performed on four emission lines in Ni I to determine populations in low-energy metastable states: 3d94s 3D3 (204.787cm−1), 3d94s 3D2 (879.816cm−1), 3d94s 3D1 (1713.087cm−1) and 3d94s 1D2 (3409.937cm−1). Fair agreement was obtained between the simulation and experimental results. The low-energy metastable states were preferentially populated after the cascade decay in contrast to weak populations in near-resonant high-energy states in Ni I.