Systematics of single and doubleK-shell-vacancy production in titanium bombarded by heavy ions

Abstract

The systematics of single and double $K$-shell-vacancy production in titanium has been investigated in the limit of zero target thickness (\ensuremath{\sim} 1 \ensuremath{\mu}g/${\mathrm{cm}}^{2}$) for incident C, N, O, F, Mg, Al, Si, S, and Cl ions over a maximum energy range of 0.5 to 6.5 MeV/amu. This corresponds to collision systems with $0.27\ensuremath{\le}\frac{{Z}_{1}}{{Z}_{2}}\ensuremath{\le}0.77$ and $0.24\ensuremath{\le}\frac{{v}_{1}}{{v}_{2 K}}\ensuremath{\le}0.85$, where ${v}_{1}$ is the projectile nuclear velocity and ${v}_{2 K}$ is the mean velocity of an electron in the target $K$ shell. The present work is divided into four major sections. (1) Single $K$-shell-vacancy production has been investigated by measuring $K\ensuremath{\alpha}$ and $K\ensuremath{\beta}$ satellite x-ray-production cross sections for projectiles incident with no $K$-shell vacancies. For incident ions with ${Z}_{1}\ensuremath{\ge}9$, the contribution due to electron-transfer processes from the target $K$ shell to outer shells of the projectile has also been noted. (2) Single $K$---shell-to-$K$-shell electron-transfer cross sections have been obtained indirectly by the measuring of the enhancement in the $\mathrm{Ti}K$ x-ray production cross section for bare incident projectiles over ions incident with no initial $K$-shell vacancies. (3) Double $K$-vacancy production has been investigated by measuring the $K\ensuremath{\alpha}$ hypersatellite intensity in ratio to the total $K\ensuremath{\alpha}$ intensity. (4) Double $K$---shell-to-$K$-shell electron-transfer cross sections have been obtained indirectly with the use of a procedure similar to that used for single $K$ to $K$ transfer. The measured cross sections have been compared to theoretical models for direct Coulomb ionization and inner-shell electron transfer and have been used to investigate the relative importance of these mechanisms for $K$-vacancy production in heavy-ion---atom collisions.