ROTATIONAL STRUCTURES IN EU-155 AND TB-157

High-spin states of Tb-157 were populated via the reactions Sm-154(Li- 7,(4)n) at 35 MeV and Nd-150(B-11,4n) at 55 MeV. Previously known band s have been extended and one new structure has been identified. The ro tational alignment behavior of the bands and band crossing systematics have been analyzed. Experimental B(ML)/B(E2) ratios for the strongly coupled bands have been extracted and compared with theoretical predic tions. New results were also obtained for the N=92 isotone (EU)-E-155. The [411]3/2 and [413]5/2 pseudospin partner bands were observed in b oth nuclei. Experimental B(E1)IB(E2) ratios have been determined in bo th (EU)-E-155 and Tb-157. However, the estimated large B(E1) strengths can be explained without static octupole deformation. The [411]3/2 ba nds in (EU)-E-155,and Tb-157 have been found identical up to spin I= 2 3/2 which might be explained by changes in deformation.