Particle-phonon interactions in 248Cf and 249Cf

The extent of particle-phonon mixing in 248Cf and 249Cf has been determined using the 249Cf(d,t) and 249Cf(d,d') reactions. K/sup pi/=2- bands were identified at 593 and 1477 keV in 248Cf. Since the only K/sup pi/=2- neutron two quasiparticle configuration expected below 2 MeV in 248Cf is ]9/2-734;5/2+ 622closing-brace2-, the second K/sup pi/=2- band is considered to be predominantly of phonon character. In 249Cf a K/sup pi/=5/2+ band at 145 keV, known from decay scheme studies, receives a measurable population in the (d,d') reaction. The phonon admixture in the 5/2+ state which results from the ]9/2-734direct-product2- phononclosing-brace configuration was determined to be (29plus-or-minus5) %. The collective admixture in the 5/2+ state was also calculated from an octupole particle-hole interaction and was found to be 35%, in good agreement with the experimental value. The anomalously low energy of the 5/2+ state could not be entirely reproduced by this calculation