1. Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk, Russia and Novosibirsk State University, 630090 Novosibirsk, Russia
2. Budker Institute of Nuclear Physics SB RAS, 630090 Novosibirsk, Russia and CERN, CH-1211 Geneva 23, Switzerland
3. Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisbon, Portugal
4. CERN, CH-1211 Geneva 23, Switzerland
5. Max Planck Institute for Physics, 80805 Munich, Germany