DoubleK-shell ionization in the electron capture decay ofMn54

The probability per $K$ capture for double $K$-shell ionization in the electron capture decay of ${}_{}{}^{54}{}_{}{}^{}\mathrm{Mn}$ was studied by recording coincidences between Cr $K$ x rays when the two $K$-shell vacancies were filled. The probability for this decay was found to be (3.6± 0.3)× ${10}^{-4\mathrm{}}$, which is a factor of 1.5 times the theoretical prediction by Suzuki and Law, and 3.2 times that of Intemann. The energy shifts of the $\mathrm{Cr} K{\alpha }^H$ and $\mathrm{Cr} K{\beta }^H$ hypersatellites were found to be 254±18 and 319±22 eV, respectively, which are about 5% higher than the calculation of Chen, Crasemann, and Mark.