A. Korichi et al., Linear polarization measurement of interband transitions in superdeformed Hg-190: Model-independent evidence for octupole vibrational structures, PHYS REV L, 86(13), 2001, pp. 2746-2749
The linear polarization of gamma rays between excited and yrast superdeform
ed (SD) states in Hg-190 was measured using the four-element CLOVER detecto
rs of the EUROBALL IV gamma -ray spectrometer. This measurement shows in a
model-independent way that the interband transitions which compete with the
highly collective in-band quadrupole transitions are largely enhanced elec
tric dipoles. Not only do these results represent the first measurement of
the multipolarity of transitions between different SD states, but they also
provide strong evidence for the interpretation of the structures in the SD
minimum of the A similar to 190 region in terms of octupole excitations.