Lifetime of the O2+ state of 72Ge determined by delayed auto-coincidence of a Ge(Li) detector

A Ge(Li) detector has been irradiated with energetic neutrons from a (d,t) neutron generator and an 241Am/Be source. The signal produced by the inelastic scattering of neutrons exciting the O2+ state in 72Ge has been split up into the pulse due to the slowing down of the recoiling 72Gesup(*) nucleus and the pulse of the conversion electron. The time separation of those two pulses has been used to deduce the lifetime of the excited O2+ state in 72Ge. The result is tau = 640.9 +- 1.1 ns. In addition, the relative response of a Ge(Li) detector on the slowing down of Ge projectiles of 800 keV has been determined to be r = 0.437 +- 0.024. (orig.)