KβKαRadiative-Transition-Probability Ratios for Elements of Low Atomic Numbers in Amorphous and Crystal Forms

Abstract

The $\frac{K\beta }{K\alpha }$ radiative-transition probabilities have been measured for 26 elements ranging in atomic numbers from ${}_{11}{}^{}{}_{}{}^{}\mathrm{Na}$ to ${}_{45}{}^{}{}_{}{}^{}\mathrm{Rh}$. The samples were in an amorphous state except ${}_{17}{}^{}{}_{}{}^{}\mathrm{Cl}$ and ${}_{35}{}^{}{}_{}{}^{}\mathrm{Br}$, which were in crystal form. The elements ${}_{11}{}^{}{}_{}{}^{}\mathrm{Na}$, ${}_{12}{}^{}{}_{}{}^{}\mathrm{Mg}$, ${}_{19}{}^{}{}_{}{}^{}\mathrm{K}$, and ${}_{20}{}^{}{}_{}{}^{}\mathrm{Ca}$ were studied in both amorphous and crystal forms. The $K$ vacancies were produced by radiation from commercial ${}_{74}{}^{}{}_{}{}^{}\mathrm{W}$ and ${}_{24}{}^{}{}_{}{}^{}\mathrm{Cr}$ x-ray tubes. The corrected measured ratios are compared with the most recent calculations based on a relativistic Hartree-Fock-Slater (RHFS) potential and relativistic screened Coulomb potential. Although the form of the dependence of this ratio on atomic number predicted on the basis of a RHFS potential seems to be correct, the experimental values are consistently higher than the calculated results. Comparison with other recent experimental results is also made.