Doubly-decoupled band in odd-odd {sup 178}Ir

Odd-odd nuclei are very complicated systems because many coupling schemes are possible between the various quasi-particle configurations. By studying these nuclei one can test different coupling schemes and their effects on the nuclear structure, e.g., the blocking effect. The previously unknown odd-odd nucleus {sup 178}Ir has been studied via the reactions {sup 156}Gd({sup 27}Al,5n) and {sup 152}Sm({sup 31}P,5n). The measurements were performed at the Holifield Heavy Ion Research Facility using the Spin Spectrometer and the Compact Ge array. The excitation functions and the multiplicity K distributions of {gamma} rays were used to identify transitions belonging to this nucleus. The preliminary study leads to assignment of several rotational bands in {sup 178}Ir, among them a doubly-decoupled band that resembles those in heavier Ir isotopes. The nature of this band and other band assignments, based on signature splitting and B(M1)/B(E2) ratios, will be discussed.