FastE1transitions and evidence for octupole-octupole and quadrupole-octupole excitations inSm144

Abstract
The nucleus Sm144 has been studied with the (n,n’γ) reaction and lifetimes of many states have been extracted from the observed Doppler shifts of the deexciting γ rays. A large number of fast E1 transitions have been observed and have led to the identification of possible members of the octupole-octupole and the quadrupole-octupole multiplets. Substantial fragmentation of the two-phonon octupole strength is indicated.