engleski

L-shell ionization of selected medium-Z elements by 0.22-0.83 MeV u-1 carbon ions

Individual L-shell x-ray production cross sections were measured with 12C ions in the energy range 0.22-0.83 MeV u-1 on Cd, In, Sb, Te, Ba, Tb and Yb targets. For these measurements the L-subshell ionization cross sections were extracted and compared with predictions of the direct ionization theories, i.e., with pertubated stationary state theory with energy loss, Coulomb deflection and relativistic corrections, the semiclassical approximation (SCA) in the united-atom limit, and SCA coupled-channel calculations involving a few lowest lying states. Better overall agreement between experiment and theory was found for SCA theory. Inclusions of the SCA coupled-channel calculations improved the agreement for the L2-subshell in the very adiabatic region, but theory fails to describe L1-ionization cross sections, especially in the 0.4<xL1<0.7 region. The degree of multiple ionization of outer shells caused by 12C ions bombardment was estimated from the x-ray line energy shifts and by comparing the x-ray intensity ratios for carbon ions and protons.

L-shell ; ionization ; carbon ions SCA

nije evidentirano