High-spin states in 109 Sn and their decay to the ground state

An extended level scheme of109Sn is presented showing high-spin states up to Ex≈ 8 MeV and spins up toJπ=(41/2+). Their decay to the 5/2+ ground state has been observed identifying a 12.8 keV 7/2+ → 5/2+ transition. A half-life of T1/2=7(1) ns has been measured for the 17/2+ state atE x =2114 keV. The experimental data are compared with the predictions of shell-model calculations.