L subshell fluorescent X-ray measurements to study CK transitions in the 66≤ Z ≤83 region

Abstract

L subshell fluorescent X-rays in Dy, Ho, Er, Lu, Ta, W, Pt, Au, Hg, Pb and Bi have been measured using synchrotron with selective creation of electron vacancies in individual subshells. Coster–Kronig (CK) yields were derived from the measured intensities. Present measurements have been made at photon energies above the edges where differences between measured and theoretical attenuation coefficients are almost negligible. Parametric trends for the results with Z were developed to cover all Zs in the range of 66–83. The trends predict the switching-off of L 1–L 2, N1 transition at Z = 67. The extent of fall /rise of f Lij values corresponding to off /on of certain transitions is found inversely proportional to the difference in binding energies of two consecutive subshells involved in the transition. For Zs above /below these rises /falls, f L13 and f L12 values are almost constants. f L23 values involving no break at Zs follow the general photoionization behaviour that ionization probability is highest at the edge energy and decreases with photon energy. Yield measurements with synchrotron radiation for Dy, Ho, Lu, Hg and Bi and experimental values for f L23, f L12 in Lu and for f L13 in Ta are being quoted for the first time.