Excitation function and half-life for the fission isomer240mPu from the238U(α, 2n)240mPu reaction

The excitation function for the fission isomer240mPu produced in the reaction of238U with α particles, has been measured at laboratory incident energies ranging from 20.1 to 27.3 MeV. A value of 3.8 −0.4 +0.6 ns was obtained for the half-life of240mPu. The results are compared with other measurements performed using different experimental methods.