NEUTRON H(11 2) BAND STRUCTURES OF PD-109,PD-111 OBSERVED IN HEAVY-ION-INDUCED FISSION/

The neutron-rich nuclei Pd-109,Pd-111 have been produced as fission fr agments following the fusion reactions Si-28,Si-30+ Yb-176 at 145 MeV and studied with the EUROGAM2 array. Two signature branches of a new b and built on the vh(11/2) orbital have been identified in Pd-109 and t he favored signature of the while? band has-been observed for the firs t time in Pd-111. The spectroscopic properties as well as the rotation al behavior of these bands are characteristic of bands expected for a prolate nuclear shape in this mass region. The effect of blocking of t he first h(11/2) quasineutron in the odd-A Pd nuclei supports the inte rpretation of the first crossing in the yrast bands of Pd-110,Pd-112 a s due to a v(h(11/2))(2) pair. [S0556-2813(98)01210-2].