Double K-shell ionization in the internal-conversion decay of 109Ag/sup m/

Double ionization of the atomic K shell accompanying the K-shell internal conversion of the 88.0-keV E3 transition of ¹⁰⁹Ag^m has been studied by recording coincidences between K x rays and Kα x rays emitted when the double vacancies are filled. The probability per K-shell internal conversion that a double K-shell vacancy is formed, T_KK, was found to be (1.53±0.24) × 10⁻⁴, and is about a factor of 5 smaller than a previous measurement. The energy shift, ΔE, of the Kα "hypersatellite" x ray was measured to be (373 ± 75) eV.RADIOACTIVITY ¹⁰⁹Ag^m; measured K x-ray---Kα x-ray coin., deduced double K-shell ionization probability and Kα "hypersatellite" x-ray energy shift.