1. Instituto de Ciencias del Espacio (ICE/CSIC and IEEC), Campus UAB, Carrer de Can Magrans, s/n 08193, Cerdanyola del Vallès (Barcelona), Spain
2. Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Leninskie Gory, GSP-1, 119991, Moscow, Russia