Charge transfer and ionization in collisions of O ~(8+) ions with excited He atoms

摘要

Two-centre atomic orbital close-coupling calculations are carried out for the cross sections of single electron capture and single ionization in O ~(8+) + He(1s1s) and O ~(8+) + He(1s3d) collisions in the velocity range from 0.6 to 2.0 a.u. The relative importance of single ionization to single capture are investigated for both systems. Our calculations are in good agreement with experimental data of O ~(8+) + He(1s1s) collision. The ratio curves also show us distinct behavior between the two collision systems. The partial electron capture cross sections for O ~(8+) + He(1s3d) collision indicate that, corresponding with the astrophysical conclusion, most of the l-levels are populated statistically for energies greater than 10 keV, and some distributions of lower n at low collision energy show a trend close to the binomial distribution.