The mean life of the $J^{\pi }=5^{-}$, $T=0\mathrm{}$ state at 4848 keV in ${}_{}{}^{18}{}_{}{}^{}\mathrm{F}$ has been measured to be 5.2±0.9 ps via the recoil-distance method. The corresponding $E2\mathrm{}$ transition strength of 14.8±2.6 Weisskopf units for decay to the $3^{-}$ level at 3791 keV establishes a strongly collective transition.

NUCLEAR REACTIONS ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}({}_{}{}^{11}{}_{}{}^{}\mathrm{B}, \alpha n){}_{}{}^{18}{}_{}{}^{}\mathrm{F}$, $E_{\mathrm{c}.\mathrm{m}.\mathrm{}}=16.7\mathrm{}$ MeV; measured mean life of 4848-keV level; deduced transition strengths; recoil-distance method, Ge(Li) detector.

• Received 17 June 1982

DOI:https://doi.org/10.1103/PhysRevC.26.1750