ΔI=4 Bifurcation in Identical Superdeformed Bands

ΔI=4 bifurcation has been observed in two superdeformed bands, the newly discovered yrast superdeformed band of 148Eu, and a previously known excited band in 148Gd. Both of these bands have moments of inertia that are identical to the yrast band of 149Gd, the first superdeformed band in which this bifurcation was observed. This first observation of ΔI=4 bifurcation in identical superdeformed bands provides a crucial test of recent models.