1. Lawrence Livermore National Laboratory, Livermore, California 94551, USA
2. Department of Physics and Astronomy, University of California Irvine, Irvine, California 92697, USA
3. General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA
4. Princeton Plasma Physics Laboratory, P.O. Box 451, Princeton, New Jersey 05843, USA
5. Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, Anhui 230031, China
6. Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831, USA
7. Columbia University, 2960 Broadway, New York, New York 10027, USA