New Structures in $^{178}$Hf and Coulomb Excitation of Isomers

Recent Coulomb excitation of a 985 MeV $^{178}$Hf beam (ATLAS) by a 500 $\mu $g/cm$^{2} \quad ^{208}$Pb target with CHICO+Gammasphere has yielded $\sim $3$\times $10$^{9}$ p-p-$\gamma $ events and approximately 368 $\gamma $-decay transitions involving 185 levels in 18 rotational bands, about 57 of which are newly identified. High-K isomer bands were populated at the 10$^{-3}$ level normalized to the ground-state band (GSB). A new ``tilted'' band crossing in the GSB provides a mechanism for the previously reported direct Coulomb excitation of the K$^{\pi }$=6$^{+}$ and 8$^{-}$ two-quasiparticle isomer bands. Direct $\gamma $-decay feeding to some of the isomer band states has been observed, which could confirm previously postulated breakdown of K conservation in the low-K bands. There is evidence of a new band connected with the 16$^{+}$, 31 year isomer band, which may be consistent with a $\gamma $-vibration built on the isomer.