Spins, Parity, Excitation Energies, and Octupole Structure of an Excited Superdeformed Band in ${}_{}{}^{194}{}_{}{}^{}Hg$ and Implications for Identical Bands

An excited superdeformed band in ${}^{194}\mathrm{Hg}$, observed to decay directly to both normal-deformed and superdeformed yrast states, is proposed to be a $K^{\pi }{=2\mathrm{}}^{-}$ octupole vibrational band, based on its excitation energies, spins, and likely parity. The transition energies are identical to those of the yrast superdeformed band in ${}^{192}\mathrm{Hg}$, but originate from levels with different spins and parities. The evolution of transition energies with spin suggests that cancellations between pairing and particle alignment are partly responsible for the identical transition energies.