Single-Neutron Levels Near The N=82 Shell Closure

The (d,p) reaction was measured with the radioactive ion beams of Sn-126 and Sn-128 in inverse kinematics at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory, utilizing the SuperORRUBA silicon detector array. Angular distributions of reaction protons were measured for several states in Sn-127 and Sn-129 to determine angular momentum transfers and deduce spectroscopic factors. Such information is critical for calculating direct (n,gamma) cross sections for the r-process as well as for constraining shell model parameters in the A approximate to 130 region. Combined with previous experiments on Sn-130 and Sn-132, these results will provide a complete set of (d, p) reaction data on even tin isotopes between stable Sn-124 and doubly-magic Sn-132.