K-shell electron shake-off accompanying alpha decay

The α spectra associated with K-shell electron shake-off in ²¹⁰Po and ²³⁸Pu decay have been determined by K x-ray-α coincidence measurements. Although the shapes of the spectra generally agree with the theoretical expectations, some discrepancies are observed. The abundances per α particle of the total K electron shake-off effect were also determined in these measurements and found to be (1.65 ±{} 0.16) ×{} 10^-6 for ²¹⁰Po and (0.83 ±{} 0.11) ×{} 10^-6 for ²³⁸Pu. These results are also compared with theoretical predictions and further experimental and theoretical studies are suggested.RADIOACTIVITY ²³⁸Pu, ²¹⁰Po; measured α-k x-ray coin. Deduced electron shake-off abundances, energy distributions. Hartree-Fock-Slater treatment.