A gamma spectrometry method used to determine burnup based on the equilibrium concentration of short halflife nuclides is proposed.Spent fuel is irradiated under constant neutron flux for a period time to make the short half-life indicator isotopes reach the equilibrium concentration,burnup value can be obtained based on the relationship between the equilibrium concentration and residual 235 U content.The theoretical simulation results and fuel irradiation experiment on theLR-0research reactor show that the...