Affiliation: | 1University of Campinas, Instituto de Fisica, Depto. de Raios Cosmicos, 13083, Campinas, SP, Brazil 2Centre d'Etudes et de Recherches de Toulouse-Office National d'Etudes et de Recherches Aerospatiales, Dep. de Technologie Spatiale, Toulouse, France 3Weber State University, Department of Physics, Ogden, Utah 84408, USA |