Lifetime Measurements in $^{162}$Dy

There has been great debate over the existence of low-lying vibrational excitations in deformed nuclei -- The original picture presented by Bohr \& Mottelson was one of collective vibrations superimposed on a deformed ground state shape, however empirically, it has been difficult to determine if the observed excitations are indeed vibrational in nature or excitations built on two-single particle states. One signature of collectivity is the extraction of absolute B(E2) transition probabilities from measured lifetimes. The complete spectroscopy of $^{162}$Dy was recently published up to 4 MeV [1], we have measured the lifetimes of several levels in the $^{162}$Dy nucleus using the GRID technique at The Institut Laue-Langevin in Grenoble, France. The Dy target was inserted into the core of a 60 MW high flux beam reactor and the line width was measured using a double flat crystal spectrometer (GAMS4) of perfect Silicon crystals. The GRID technique allows measurements of lifetimes from a few picoseconds and lower. Preliminary lifetime measurements will be presented.\\[4pt][1] A. Aprahamian, {\it et al.}, Nucl. Phys. A {\bf 764} 42 (2006). This work was supported by the NSF under contract number PHY07-58100.