Study ofL-subshell ionization of Sm by protons: 0.3-2.0 MeV

The $L$-subshell ionization processes in Sm for proton bombardment over the energy range 0.3-2.0 MeV were studied using a thin Sm target (15.0 ${\mathrm{\mu }\mathrm{g}/\mathrm{c}\mathrm{m}}^2$). The total $L$-shell x-ray cross section and x-ray cross sections for the transitions $\mathrm{Ll}$, $L{\alpha }_{1,2}$, $L{\gamma }_1$, and $L{\gamma }_{2,3}$ were determined at each proton energy. Calculations for the total $L$-shell x-ray and ionization cross sections and $L$-subshell ionization cross sections were performed for the non-relativistic plane-wave born approximation (PWBA), constrained-binary-encounter approximation (CBEA), and binary-encounter approximation (BEA). Comparisons of the theoretical predictions are made to the experimental values for the total $L$ x-ray production cross section, total $L$-shell ionization cross section, relative intensities of the $\frac{L{\alpha }_{1,2}}{\mathrm{Ll}}$, $\frac{L{\alpha }_{1,2}}{L{\gamma }_1}$, $\frac{L{\alpha }_{1,2}}{L{\gamma }_{2,3}}$, and $\frac{L{\gamma }_1}{L{\gamma }_{2,3}}$ ratios, and the x-ray production cross sections for the $L{\alpha }_{1,2}$, $L{\gamma }_{2,3}$ and $L{\gamma }_1$ transitions. The results of this work show that the nonrelativistic PWBA theory is in reasonable agreement with the $L_I$-subshell processes measured in Sm for protons. The CBEA does not predict the appropriate structure observed in the $L_I$ subshell. The BEA calculations show that there are major differences between the data for Sm and the predictions of that theory.