1. Centro Ricerche Enrico Fermi—Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, 00184 Rome, Italy
2. Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
3. Department of Physics, University of Trieste, 34127 Trieste, Italy
4. Section of Trieste, Istituto Nazionale di Fisica Nucleare, 34149 Trieste, Italy
5. IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, 077125 Măgurele, Romania
6. Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Science, 1030 Wien, Austria
7. Excellence Cluster Universe, Technische Universität München, 80333 München, Germany
8. Department of Mathematics, Rutgers University, New Brunswick, NJ 08854, USA
9. Department of Physics of Complex Systems, Eötvös Loránd University, 1117 Budapest, Hungary
10. Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, 1525 Budapest, Hungary
11. Laboratori Nazionali del Gran Sasso, INFN, 67100 L’Aquila, Italy