X-ray emission spectra induced by ion-atom collisions I : single and double K-shell ionization

Abstract

Experimental cross sections were determined for the single and double K-shell ionization of Be, B and O atoms by H (0.3-2.0 MeV), He (0.25-2.0 MeV), N (0.3-1.1 MeV) and Ar (0.3-1.8 MeV) ion bombardments using a high resolution Bragg spectrometer. The results of the single K-shell ionization for H and He ion bombardments showed a good agreement with the calculated result by the Coulomb excitation of the binary-encounter approximation (BEA), while those of the heavy ion bombardments were understood in terms of the electron promotion model. The cross sections of the double K-shell ionization for the H and He ion bombardments were for the first time measured, and the results showed that the cross section was dependent on Z_1^4 of the projectile nuclear charge and a maximum cross section was obtained at E/λU=1.