1. Lawrence Livermore National Laboratory, Livermore, California 94550, USA
2. Stanford University, Stanford, California 94305, USA
3. Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
4. Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA
5. General Atomics, 3550 General Atomics Court, San Diego, California 92121, USA
6. SLAC National Accelerator Laboratory, Menlo Park, California 94309, USA
7. Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany