High-spin states in odd-odd 164Lu

Abstract High-spin states in odd-odd 164 Lu have been studied using 19 F and 23 Na induced fusion-evaporation reactions. Three strongly coupled rotational bands have been established and three decoupled bands were tentatively assigned to 164 Lu. The band crossing frequencies, energy sig-nature splittings, and relative transition probabilities were deduced from experimental data and compared with neighboring even-even and odd- A nuclei. An anomalously large band crossing frequency was observed in the excited band, and a pronounced signature inversion was observed in the yrast band of 164 Lu. These anomalies may be associated with residual neutron-proton interactions.