Affiliation: | (1) Present address: Department of Physics, Vanderbilt University, 37235 Nashville, TN, USA;(2) Department of Physics, University of Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium;(3) Joint Institute for Heavy Ion Research, HHIRF, 37831 Oak Ridge, TN;(4) UNISOR, Oak Ridge Associated Universities, 37831 Oak Ridge, TN, USA;(5) Present address: Dept. of Physics, Tsinghua University, Beijing, P. R. China |