Evidence for octupole correlation in Z=50 Sn isotopes: Spectroscopy of Sn112

High-spin states in ^112Sn were investigated using the ^103Rh (^12C, 1p2n) reaction at a beam energy of 62 MeV. Six electric dipole E1 transitions linking positive- and negative-parity intruder bands have been identified in ₅₀^112Sn through -ray spectroscopy. The experimental reduced E1 transition probabilities B (E1), derived from level lifetimes by means of the Doppler-shift attenuation method, are of the order of 10^-4 W. u. , which gives evidence for the octupole correlation in ^112Sn. The systematics of the reduced E1 transition probabilities and neutron energy levels of 5/2^+ and 11/2^- in Xe isotopes suggest an enhanced octupole correlation at neutron number N=62, which is supported by the relativistic Hartree-Bogoliubov calculations.