Study of high-spin states in odd Sn isotopes

Level schemes of odd Sn isotopes (A = 109-117) have been studied by an in-beam spectroscopy method through (α, xn) reactions. High-spin states above the γhsub(11/2) states were systematically observed. The level sequences show characteristics quite similar to those of adjacent even Sn isotopes. The level schemes are divided into two regions at about 2 MeV excitation from the γhsub(11/2) states. The lower-energy region can be understood by particle-core coupling schemes, while the higher-energy region is interpreted by three-quasiparticle configurations of ssub(1/2), dsub(3/2), dsub(5/2), gsub(7/2) and hsub(11/2) neutrons. Particle-core coupling schemes are discussed based on the neutron number dependence of the energy ratio (Esub(15/2-)-Esub(11/2-))/Esub(2+). (Auth.)