Measurement of theL2-L3Coster-Kronig transition probability in Nd(Z=60)

The $L_2$-$L_3$ Coster-Kronig transition probability $f_{23}$ in Nd was measured using multiparameter K-vs-L x-ray coincidence techniques. The Nd x rays were obtained from a radioactive source of ${}_{}{}^{145}{}_{}{}^{}\mathrm{Pm}$. High-energy-resolution germanium and silicon detectors were used to detect the K and L x rays, respectively. A method is described to correct for the very important contribution of K${\alpha }_1$ x rays to the K${\alpha }_2$ x-ray peak as well as for the small contribution of K${\alpha }_2$ x rays to the K${\alpha }_1$ x-ray peak. The contribution of Lη x rays to the measured K${\alpha }_2$-(Lα+Lη) coincidences was calculated and subtracted. The value obtained, $f_{23}$=0.146±0.005, is lower than that predicted (0.170) by the latest theoretical calculations, confirming a trend of deviations from theory recently observed in atoms of higher atomic number. It differs, however, from another recently reported value of 0.123±0.013. .AE