Department of Physics, University of California at Berkeley, Berkeley, CA, 94720-7300 USA;3. Helmholtz Institute Mainz, Johannes Gutenberg University, 55099 Mainz, Germany

School of Physics, University of New South Wales, Sydney, 2052 Australia;4. Petersburg Nuclear Physics Institute of NRC “Kurchatov Institute”, Gatchina, 188300 Russia

Department of Physics, St. Petersburg Electrotechnical University “LETI”, Prof. Popov Str. 5, 197376 St. Petersburg, Russia;5. Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 7610001 Israel;6. JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO, 80309 USA