Affiliation: | (1) Department of Physics, University of California at San Diego, 92093 La Jolla, California;(2) Present address: Department of Physics, Indiana University, 47401 Bloomington, Indiana;(3) Institute for Theoretical Physics, University of California, 93106 Santa Barbara, California;(4) Present address: Supercomputer Computations Research Institute, Florida State University, 32306 Tallahassee, Florida;(5) Fachbereich Physik, Universitat Kaiserslautern, D6750 Kaiserslautern, Germany;(6) Physics Department, University of Edinburgh, EH9 3JZ Edinburgh;(7) Department of Physics, University of California, 93106 Santa Barbara, California |