Spectral characteristics of VLF sferics associated with TGFs

Andrew Mezentsev1, Nikolai Ostgaard2, Steven A Cummer3, Dr. Francisco J. Perez-Invernon, PhD4 and Nikolai G Lehtinen2, (1)Birkeland Centre for Space Science, University of Bergen, Bergen, Norway, (2)University of Bergen, Department of Physics and Technology, Bergen, Norway, (3)Duke University, Department of Electrical and Computer Engineering, Durham, United States, (4)Instituto de AstrofĂ­sica de AndalucĂ­a (IAA - CSIC), Granada, Spain