Highly precise measurements of the relative gamma-ray intensities for 56Mn and 72Ga

Precise relative γ-ray intensities of 56Mn and 72Ga produced by neutron irradiation of natural Mn3O4 and enriched 71Ga2O3 (99.8%) were measured by an HPGe detector with highly-precisely calibrated detection efficiencies. As both nuclides exhibit no β branch to the ground state, the absolute emission probabilities of the 846.8 keV γ ray for 56Mn and 834.0 keV γ ray for 72Ga were determined to be 0.9888±0.0014 and 0.9553±0.0005, respectively.