ELF whistler events with a reduced intensity observed by the DEMETER spacecraft

Jan Zahlava1, Frantisek Nemec1, Ondrej Santolik2,3, Ivana Kolmasova3,4 and Michel Parrot5, (1)Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic, (2)Department of Space Physics, Institute of Atmospheric Physics CAS, Prague, Czech Republic, (3)`Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic, (4)Department of Upper Atmosphere, Institute of Atmospheric Physics CAS, Prague, Czech Republic, (5)CNRS - LPCE, Orleans, France