Very Low Frequency Whistler Mode Wave Events Observed Simultaneously by the Kannuslehto Station and Van Allen Probes

0573096 - ÚFA 2024 RIV US eng J - Journal Article
Bezděková, B. - Němec, F. - Manninen, J. - Santolík, Ondřej - Hospodarsky, G. B. - Kurth, W. S.
Very Low Frequency Whistler Mode Wave Events Observed Simultaneously by the Kannuslehto Station and Van Allen Probes.
Journal of Geophysical Research-Space Physics. Roč. 128, č. 1 (2023), č. článku e2022JA031078. ISSN 2169-9380. E-ISSN 2169-9402
Institutional support: RVO:68378289
Keywords : VLF emissions * ULF waves * chorus
OECD category: Fluids and plasma physics (including surface physics)
Impact factor: 2.8, year: 2022
Method of publishing: Limited access
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022JA031078

Events characterized by substantial intensity enhancements in the frequency range between about 1.5 and 4 kHz in the measurements of the ground-based Kannuslehto station, Finland are analyzed. Altogether, as many as 465 events are identified in the Kannuslehto data measured during the campaigns between December 2012 and October 2019. It is shown that the events usually last for several hours and they occur preferentially on the dawn side during geomagnetically active periods. Simultaneous measurements performed by the Van Allen Probes spacecraft are used to reveal the L-shells and magnetic local times where a corresponding intensity increase occurs in space. A backward ray tracing analysis is further employed to investigate the wave propagation between the tentative source region and the ground. Wave normal angles of waves eventually detectable at Kannuslehto are determined and compared with those obtained from a detailed wave analysis. Either a wave ducting, propagation in the Earth-ionosphere waveguide, or their combination seem to be needed for the waves to reach Kannuslehto.
Permanent Link: https://hdl.handle.net/11104/0343681