MEASUREMENT OF LL, L-ALPHA, L-BETA, AND L-GAMMA X-RAY-PRODUCTION CROSS-SECTIONS IN RARE-EARTH ELEMENTS BY 60-KEV PHOTONS

Our earlier measurements [Shatindra, Allawadhi, and Sood, Phys. Rev. A 31, 2918 (1985)] of Ll, L-alpha, L-beta, and L-gamma x-ray production cross sections in elements with 73 less-than-or-equal-to Z less-than-or-equal-to 92 by 60-keV photons have been extended to 11 rare-earth elements in the range 57 less-than-or-equal-to Z less-than-or-equal-to 68 in order to examine enhancement in L-subshell x-ray production due to transfer of vacancies from the K to the L shell. The measured values of absolute cross sections have been interpreted in terms of K-shell photoelectric cross sections, probabilities of K --> L radiative and nonradiative transitions, L-subshell photoelectric cross sections, fluorescence yields, Coster-Kronig transition probabilities, and radiative decay rates. Fairly good agreement between the experimental and calculated values indicates indirectly the correctness of the theoretical calculations of the atomic parameters in terms of which the experimental results have been interpreted.