1. Department of Physics, Universidade Federal da Paraíba, João Pessoa, Brazil.
2. Faculty of Applied Physics, Department of Physics, Politehnica University of Bucharest, Bucharest, Romania.
3. Joint Institute for Nuclear Research, Dubna, Russia.
4. Horia Hulubei National Institute of Physics and Engineering, Bucharest, Romania.
5. Faculty of Physics, Lomonosov Moscow State University, Moscow, Russia.