Natural widths and Coster–Kronig transitions of L X-ray spectra in elements between Pd and Sb

The Lα and Lβ X-ray emission spectra in the elements between Pd (Z=46) and Sb (Z=51) were measured using a high-resolution double-crystal vacuum spectrometer. The relative intensities of satellite structures, which originate in L1L3M4,5 Coster–Kronig transitions, were estimated to that of each diagram line, and compared with calculated values. According to the work of Chen et al. [1977a. Theoretical L-shell Coster–Kronig energies 11⩽Z⩽103. At. Data Nucl. Data Tables 19, 97–151], Salgueiro et al. [1987. J. Phys. (Paris) 48 Colloq. C9, 609] and Vlaicu et al. [1998. Investigation of the 74W L emission spectra and satellites. Phys. Rev. A 58, 3544] L1L3M4 Coster–Kronig transition is forbidden for 50⩽Z⩽77, and L1L3M5 Coster–Kronig transition is forbidden for 50⩽Z⩽73. The results suggest that L1L3M4,5 Coster–Kronig transitions may be allowed even for Sn (Z=50) and Sb (Z=51).