1. Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
2. LIDYL, CEA-Université Paris-Saclay, CEA Saclay, 91 191 Gif-sur-Yvette, France
3. SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
4. Lawrence Livermore National Laboratory, Livermore, California 94550, USA
5. Deutsches Elektronen Synchrotron (DESY), Hamburg, Hamburg 22607, Germany