L-SHELL IONIZATION IN AU BY O5-ION AND NI5+-ION IMPACT()

The L X-ray production cross sections in gold by 60 to 72 MeV O5+ ions and 58 to 87 MeV Ni5+-ions have been measured. The L-subshell ionizat ion cross sections derived from these experimental results have been c ompared with the direct ionization theories viz. plane wave Born appro ximation (PWBA) theory and modified perturbed-stationary-state theory with energy loss, Coulomb deflection and relativistic effects (MECPSSR ). A new procedure has been described to account for the change in the yield ratio L beta(1)/L beta(2,15) with energy, for Ni5+-ion impact o n gold. The L sub-shell ionization cross sections have been derived fr om L beta(1), L beta(4) and L beta(2,15), lines of the L beta group in addition to those calculated by the conventional Dart TRY3 technique using L alpha, L gamma(1), and L gamma(2,3) X-ray lines. From the shif t in the energies of various L X-ray lines and changes in their intens ities, 3 and 5 spectator vacancies in the M- and N-shells in gold have been estimated with O5+-ion impact while 7, 20 and 4 to 6 spectator v acancies have been inferred in the M-, N- and O-shells respectively wi th Ni5+-ion impact in the energy range of the projectiles undertaken i n the present studies.