Study of high-spin states in the nucleus 149Eu

In-beam studies of high-spin states in Eu-149 are reported. The level scheme extends up to an excitation energy of 7.1 MeV and a spin of 55/2HBAR. This nucleus is weakly deformed and most of the high-spin structure is interpreted through its multi-particle-hole nature. Octupole-phonon vibrations coupled to multi-particle-hole states are observed and discussed. In contrast with the Z less-than-or-equal-to 62 isotones, there is no conclusive evidence in Eu-149 for octupole deformation induced by rotation.