-
Author(s):
X. Ma, H.P. Liu, Z.H. Yang, Y.D. Wang, X.M. Chen, Z.Y. Liu, I. Murakami and C. Namba
-
Title:
Cross-section Data Measured at Low Impact Energies for Ar^9+ Ions on Argon and Neon Targets
Date of publication:
Apr. 2003
-
Key words:
Ion-atom collision, charge exchange, cross section, multiply excited states
-
Abstract:
Multiple electron transfer was systematically studied for Ar^{q+} + Ne, and Ar^{q+} + Ar (q = 8, 9, 11, 12) collision systems by using coincidence experimental technique for incident energies from 80keV to 240keV. Various sub-processes of charge exchange were identified and their cross sections were measured in the experiments. The dependencies of cross sections of multiple charge exchange on the charge states of projectiles and the charge states of recoil ions were discussed respectively for the collision systems. Based on the Molecular Coulombic overBarrier Model (MCBM), four steps are suggested in describing HCI-atom collisions: molecularizing of target electron ->formation of molecular -> dissociation of the molecular and formation of multiply excited scattered ions and recoil ions ->autoionizing decay of multiply excited ions. By comparison with experimental data, it was found that the calculated absolute projectile charge changing cross sections are in good agreements with experimental results. It is concluded that the autoionization of multiply excited ions may be the dominant reason of transfer ionization in low energy HCI-atom collisions.
-
|
