Study of Hf-169 at high rotational frequency

High-spin properties, of the nucleus Hf-169 have been studied through the f usion evaporation reaction Zr-96(Ge-76,3n)Hf-169 at a beam energy of 310 Me V. The known rotational bands have been extended considerably and 6 new ban ds have been established, four of which form coupled bands with pronounced M1 connections. Quasiparticle assignments are suggested for the new band st ructures, and it appears that coupling to vibrational degrees of freedom pl ays a. role. Both coupled bands involve the excitation of quasiprotons. In the region of highest spin, a large alignment gain is interpreted in terms of a mixed crossing where an h(9/2) and an h(11/2) quasiproton provide the two signatures of the aligning configuration.