BismuthL-Subshell Fluorescence Yields and Coster-Kronig Transition Probabilities from Decay ofPb210(RaD)

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Ultrahigh-resolution (436-eV full width at half-maximum at 14.4 keV) Ge(Li) and Si(Li) x-ray detectors have been used to investigate $L$ x rays of Bi from the decay of carrier-free ${\mathrm{Pb}}^{210}$ ($\mathrm{Ra}D$). A detailed study of the detection efficiencies was carried out, in order to take into account effects due to Ge $K$ x-ray escape, and absorption in layers of inactive Ge or Si, Au, Al, and Be present between the source and active detector volume. A DuPont curve-resolving analog computer was used to resolve the $L$ x-ray spectrum into further components. The resolved spectra thus yielded 10 $L$ x-ray groups, together with their absolute intensities in ${\mathrm{Pb}}^{210}$ decay. Combining these results with recent precision $L$-conversion and $L$ Auger electron absolute intensities in this decay, the following set of $L$-subshell fluorescence yields (${\ensuremath{\omega}}_{i}$), Auger yields (${a}_{i}$), and Coster-Kronig transition probabilities (${f}_{\mathrm{ij}}$) are obtained: ${\overline{\ensuremath{\omega}}}_{L}=0.330\ifmmode\pm\else\textpm\fi{}0.016$, ${\ensuremath{\omega}}_{3}=0.345\ifmmode\pm\else\textpm\fi{}0.018$, and ${\ensuremath{\omega}}_{1}=0.095\ifmmode\pm\else\textpm\fi{}0.005$; ${\overline{a}}_{L}=0.670\ifmmode\pm\else\textpm\fi{}0.016$, ${a}_{3}=0.655\ifmmode\pm\else\textpm\fi{}0.018$, and ${a}_{1}=0.133\ifmmode\pm\else\textpm\fi{}0.009$; and ${f}_{12}+{f}_{13}=0.772\ifmmode\pm\else\textpm\fi{}0.011$. Using the recent value of ${f}_{23}=0.164\ifmmode\pm\else\textpm\fi{}0.016$ at $Z=82$, determined by Rao et al., the following additional quantities are evaluated: ${\ensuremath{\omega}}_{2}=0.23\ifmmode\pm\else\textpm\fi{}0.02$, ${a}_{2}=0.61\ifmmode\pm\else\textpm\fi{}0.02$, ${f}_{12}=0.18\ifmmode\pm\else\textpm\fi{}0.02$, and ${f}_{13}=0.58\ifmmode\pm\else\textpm\fi{}0.02$. A remarkably strong $E2$ $L$ x-ray transition (${L}_{1}\ensuremath{-}{M}_{4,5}$) also was observed in the decay of ${\mathrm{Pb}}^{210}$ ($\mathrm{Ra}D$).