An experimental investigation of some KLL and L3MM Auger transitions for Z=58, 59, and 61:

Abstract

Abstract The KL1L2 Auger doublet of 14059Pr and the KLL Auger spectrum of 14561Pm from the electron capture decay of 140Nd and 145Sm, respectively, have been measured with high instrumental resolutions using a combined electrostatic spectrometer and sources prepared by a modified Langmuir–Blodgett method. An exceptional agreement of the determined KL1L2(3P0)/(1P1) intensity ratios of 0.42(2) and 0.45(1) for 140Pr and 145Pm, respectively, with the respective calculated values of 0.419 and 0.450 has proved the predicted strong influence of the relativistic effects on the KL1L2(3P0) transition intensity. While the measured relative intensities of the KLL transitions in 145Pm were found to agree well with the relativistic intermediate coupling calculations, the measured relative energies deviate from results of the widely used semi-empirical calculations. A doublet structure of the KL2L3(1D2) line of 145Pm with a splitting of 18.3(6) eV has been observed. We made an assumption that this structure originates in two different K shell excitation processes. The measured absolute energies of 28 397(3), 29 423.1(26), and 31 542.9(15) eV for the KL2L3 transition in 140Ce, 140Pr, and 145Pm, respectively, were found to be higher by about 20 eV than the semi-empirical values. The most intense L3MM line groups of 145Pm have also been measured but not evaluated. The absolute energy of the L3M4M5(1G4) transition has been determined to be 4342.6(16) eV. The energy of the M1 61.2 keV nuclear transition in 145Pm has been improved to be 61 226.5(17) eV using the measured energy of 16 042.5(15) eV of the K-61.2 conversion line. Values of 19.2(5) and 25.3(9) eV were determined for natural widths of the K shell and KL2L3 transition of 145Pm, respectively.