Collective band structures of the nuclei near N=82 closed shell in A=135 region

Through heavy-ion nuclear reactions and in-beam γ-ray spectroscopy technique, the high spin states of odd A ¹³⁷La and odd-odd ¹³⁸Pr nuclei which are located near the N=82 closed shell on A=135 region, have been studied. The ¹³⁰Te(¹¹B, 4n) and ¹²⁸Te(¹⁴N, 4n) reactions were used to populate the level states for ¹³⁷La and ¹³⁸Pr respectively. The level schemes of these two nuclei have been extended. In ¹³⁷La, four collective bands have been newly identified. Among them, the near-yrast band is with weak prolate deformation, and another one belongs to a oblate band. In ¹³⁸Pr, six collective bands have been observed. The yrast band is with weak prolate deformation also, and all the other five bands, two of which are newly identified by the present work, are assigned as the oblate bands. The characteristics for these collective bands, such as the signature inversion, the configuration origination etc. have been discussed.