Messung niederenergetischer Neutroneneinfang-Strahlung vom Re 186 und Re 188

Abstract

A crystal-spectrometer was used for the measurement of neutron capture y-rays of Re 186 and Re 188 within the energy range of 30 and 350 (resp. 210) kev. A sudden decrease in intensity was found for both 69.5 and 105.8 kev lines of Re 188m when the reactor was shutt off. This fact, coincidence measurements and measurements with a scintillation spectrometer cannot be explained on the base of the level schemes given in the Nuclear Data Sheets, the tabels of LANDOLT-BÖRNSTEIN or KUNZ-SCHINTLMEISTER. The investigation of the conversionelectron-spectrum shows the 63.5 and 105.8 kev transition to be of Ml-type. The KLI X-radiation is (1.9 ± 0.7) • 10-3 times as intense as the Kα1-radiation.