Study On Single-Electron Loss In Collisions Of Lithium-like Ions With Helium Atoms At Low And Intermediate Energies

The cross sections for single-electron loss (SEL), single-electron loss associated with single ionization (SELSI) and single-electron loss associated with double ionization (SELDI) in collisions of lithium-like ions B2+, C3+N4+and O5+with helium atoms in the energy range from20to900keV/u have been calculated by considering the impact parameter dependence and the distribution of both target and projectile electrons based on the Bohr-Lindhard (B-L) model. The calculated results are compared with the available experimental data. Reasonable agreements are obtained.For a given projectile, the effective impact-parameter ranges for SEL, SELSI and SELDI decrease in sequence. The energy dependences of cross sections for the above three processes are similar. They rise raidly until reaching the peak position with the extreme energy Emax, and then drastically reduce with the increasing impact energy. The peak position slightly depends on the collision process. For a given impact energy, the values of cross sections satisfy:σSEL>σSELSI>σSELDI.For a given process, the effective impact-parameter ranges for B2+, C3+, N4+and O5+also decrease in sequence. At the same time, Emax moves towards the higher energy with the increasing atomic number ZP.