An Upper Limit for the Probability of Nuclear Excitation by Electron Transition in 235U
We have attempted to observe nuclear excitation by electron transition (NEET) in 235U with Mo K X-ray irradiation and off-line radioactivity measurement. Nuclear excitation of the 13-keV level was measured through the isomer radioactivity. An upper limit for the NEET probability was obtained as P < 9 × 10−10.