1. SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94301, USA
2. Laboratoire de Physique Subatomique et de Cosmologie, Université Grenoble-Alpes, CNRS/IN2P3, 53 avenue des Martyrs, 38026 Grenoble, France
3. Southern Methodist University, Dallas, TX 75275, USA
4. PRISMA Cluster of Excellence, Institut für Physik, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
5. Centre for Theoretical and Mathematical Physics and Department of Physics, University of Cape Town, Rondebosch 7700, South Africa
6. Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA 94551, USA
7. Physics Department, University of California at Davis, Davis, CA 95616, USA