Whistler influence on the overall VLF wave intensity in the upper ionosphere

0490180 - ÚFA 2019 RIV US eng J - Článek v odborném periodiku
Záhlava, J. - Němec, F. - Pincon, J. L. - Santolík, Ondřej - Kolmašová, Ivana - Parrot, M.
Whistler influence on the overall VLF wave intensity in the upper ionosphere.
Journal of Geophysical Research-Space Physics. Roč. 123, č. 7 (2018), s. 5648-5660. ISSN 2169-9380. E-ISSN 2169-9402
Grant CEP: GA ČR GA17-07027S
Grant ostatní: AV ČR(CZ) AP1401
Program: Akademická prémie - Praemium Academiae
Institucionální podpora: RVO:68378289
Klíčová slova: Demeter spacecraft * propagation analysis * temporal signatures * equatorial noise * field experiment * electric-field * radiation * emissions * plasmasphere * chorus
Obor OECD: Fluids and plasma physics (including surface physics)
Impakt faktor: 2.821, rok: 2018
https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2017JA025137

We investigate the influence of lightning‐generated whistlers on the overall intensity of electromagnetic waves measured by the DEMETER spacecraft (2004 ‐ 2010, quasi Sun‐synchronous polar orbit with an altitude of about 700 km) at frequencies below 18 kHz. Whistler occurrence rate evaluated using an onboard neural network designed for automated whistler detection is used to distinguish periods of high and low whistler occurrence rates. It is shown that, especially during the night and particularly in the frequency‐geomagnetic latitude intervals with a low average wave intensity, contribution of lightning generated whistlers to the overall wave intensity is significant. At frequencies below 1 kHz, where all six electromagnetic wave components were measured during specific intervals, the study is accompanied by analysis of wave propagation directions. When we limit the analysis only to fractional‐hop whistlers, which propagate away from the Earth, we find a reasonable agreement with results obtained from the whole data set. This also confirms the validity of the whistler occurrence rate analysis at higher frequencies.
Trvalý link: http://hdl.handle.net/11104/0284464