1. General Atomics, San Diego, California 92121, USA
2. Oak Ridge Associated Universities, Oak Ridge, Tennessee 37830, USA
3. Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712, USA
4. Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
5. Lawrence Livermore National Laboratory, Livermore, California 94550, USA
6. Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544, USA