Developing 152Eu into a standard for detector efficiency calibration

A γ–γ coincidence experiment was performed to check the 152Eu 13-year decay scheme and the placement of the observed γ-ray transitions. The multi-detector array for residual activity measurement of the Linear Accelerator Laboratory was used. The source activity was 1 MBq, and about 109 coincidence events were observed. About 30 γʹs were placed in the decay scheme and four 152Sm levels were added to the previously known set of levels fed in 152Eu 13-year decay.