Lifetimes of high-spin levels in39Ar

The high-spin states in³⁹Ar at 2651, 3992, 4543, and 5536 keV were excited in oxygen-induced fusion-evaporation reactions. Mean lifetimes ofτ _m =1.0±0.2, 1.2±0.3, 1.6±0.3, and <1 ps were determined for these levels, respectively, by means of the recoil distance Doppler shift technique. The transition rates are discussed in terms of the Bansal-French weak-coupling model.