The πh_11/2 Band-Crossing and Possible OctupoleCorrelations in ¹²²Ba

High-spin states in ¹²²Ba have been investigated in the ¹⁰⁷Ag(¹⁹F, 4n) reaction by in-beam γ-ray spectroscopic methods. The ground-state band has been observed with spin up to 20ħ and a negative-parity band is identified with spin state up to 19ħ. A band-crossing in the yrast band is observed at a rotational frequency of ħω ≈ 0.36 MeV and, in accordance with cranked shell model calculations, is interpreted as arising from the alignment of two h_11/2 protons. Strong E1 transitions between the negative-parity and the yrast bands have been observed, which are proposed as possible evidence for octupole correlations.