Single-neutron excitations in neutron-rich Ge83 and Se85

J. S. Thomas, University of Surrey
G. Arbanas, Oak Ridge National Laboratory
D. W. Bardayan, ORNL Physics Division
J. C. Blackmon, ORNL Physics Division
J. A. Cizewski, Rutgers University–New Brunswick
D. J. Dean, ORNL Physics Division
R. P. Fitzgerald, The University of North Carolina at Chapel Hill
U. Greife, Colorado School of Mines
C. J. Gross, ORNL Physics Division
M. S. Johnson, Lawrence Livermore National Laboratory
K. L. Jones, The University of Tennessee, Knoxville
R. L. Kozub, Tennessee Technological University
J. F. Liang, ORNL Physics Division
R. J. Livesay, Oak Ridge National Laboratory
Z. Ma, The University of Tennessee, Knoxville
B. H. Moazen, The University of Tennessee, Knoxville
C. D. Nesaraja, ORNL Physics Division
D. Shapira, ORNL Physics Division
M. S. Smith, ORNL Physics Division
D. W. Visser, The University of North Carolina at Chapel Hill


The H2(Ge82,p)Ge83 and H2(Se84,p)Se85 reactions were studied with radioactive beams of Ge82 and Se84 at beam energies of Ebeam=330 and 380 MeV, respectively. Excitation energies, proton angular distributions, and asymptotic normalization coefficients have been determined for the lowest lying states of Ge83 and Se85. Spectroscopic factors have also been extracted under normal assumptions of the bound-state potential properties in the distorted waves Born approximation analysis. However, the peripheral character of the measurements leads to large uncertainties in this extraction. Shell-model calculations have been performed in the region above Ni78, comparing the single-particle properties of the even-Z,N=51 nuclei up to Zr91 and including Ge83 and Se85. Direct-semidirect neutron capture calculations to Ge83 and Se85 have also been performed using the spectroscopic input from these (d,p) reaction measurements. © 2007 The American Physical Society.