1. Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
2. Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
3. Engineering Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
4. Division of Materials Science and Engineering, Ames Laboratory, Iowa State University, Ames, Iowa 50011, USA