1. Negative-parity Bands of 115 Pd and Band Structures in 113,115,117 Pd D. Fong, E.F. Jones, P.M. Gore, J.K. Hwang, A.V. Ramayya, J.H. Hamilton, and Y.X. Luo Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37235 W.B. Walters University of Maryland, College Park, MD 20742 J.O. Rasmussen, I.Y. Lee, A.O. Macchiavelli, and S.C. Wu Lawrence Berkeley National Laboratory, Berkeley, CA 94720 M. Stoyer Lawrence Livermore National Laboratory, Livermore, CA 94550 S.J. Zhu Department of Physics, Tsinghua University, Beijing, P.R. China A.V. Daniel, G.M. Ter-Akopian, Yu.Ts. Oganessian Flerov Laboratory for Nuclear Reactions, JINR, Dubna, Russia J.D. Cole Idaho National Environmental and Engineering Laboratory, Idaho Falls, ID 83415 R. Donangelo Universidade Federal do Rio de Janeiro, CP 68528, RG Brazil W.C. Ma Department of Physics, Mississippi State University, Mississippi 39762

2. We have used our  -  -  data (5.7x10 11 triples and higher folds) from the spontaneous fission of 252 Cf taken with Gammasphere to study the odd-mass 113,115,117 Pd nuclei in order to probe the deformations and structure arising from the behavior of the h 11/2 neutron shell in the neutron-rich region beyond the subshell closure at N=64.

4. FIG. 1: Previous negative-parity level systematics in 107,109,111,113,115,117 Pd (oldcurves.eps)

14. A new 85.1-keV transition was identified in 113 Pd. This indicates the spin and parity of the isomeric state is 9/2 - rather than the previously assigned 11/2 -. New low-energy transitions are confirmed in 115,117 Pd. In 115 Pd, the 39.0.- and 49.0-keV transitions are shown to be in prompt coincidence. This coincidence relationship indicates a spin and parity assignment for the 115 Pd ground state to be 1/2 + rather than the previously assigned 3/2 +.

15. These Pd nuclei exhibit very similar behaviors in their negative-parity structures, with common 11/2 - decoupled rotational bands. The ground state J  changes from 5/2 + in the lower- mass Pd nuclei to 1/2 + in 115 Pd and to 3/2 + in 117 Pd. New high-spin levels beginning at 21/2 - in 113,115,117 Pd show the same energy systematic trend as the other negative-parity levels, with the lowest energy occuring in 113 Pd.