[1] SLAC Natl Accelerator Lab, Stanford PULSE Inst, Menlo Pk, CA 94025 USA
[2] SLAC Natl Accelerator Lab, Menlo Pk, CA 94025 USA
[3] Imperial Coll London, Dept Phys, Blackett Lab, London, England
[4] Stanford Univ, Dept Phys, Stanford, CA 94305 USA
[5] Max Planck Inst Quantum Opt, Garching, Germany
[6] Ludwig Maximilians Univ Munchen, Phys Dept, Munich, Germany
[7] Paul Scherrer Inst, Villigen, Switzerland
[8] Univ Connecticut, Phys Dept, Storrs, CT USA
[9] Ecole Polytech Fed Lausanne, LUXS, Lausanne, Switzerland
[10] Stanford Univ, Dept Appl Phys, Stanford, CA 94305 USA
[11] Ohio State Univ, Dept Phys, Columbus, OH 43210 USA
[12] Univ Kassel, Inst Phys, Kassel, Germany
[13] Univ Kassel, CINSaT, Kassel, Germany
[14] KLA Tencor Corp, Milpitas, CA USA
[15] Tech Univ Dortmund, Zentrum Synchrotronstrahlung, Dortmund, Germany
[16] Helmholtz Zentrum Berlin, Berlin, Germany