Simultaneous observation of chorus and hiss near the plasmapause - INSU - Institut national des sciences de l'Univers Access content directly
Journal Articles Journal of Geophysical Research: Atmospheres Year : 2012

Simultaneous observation of chorus and hiss near the plasmapause


[1] On 4 August 2010 a moderate geomagnetic storm occurred with minimum Dst of À65 nT and maximum K p of 7À. Shortly after the onset of this storm, VLF chorus was observed at Marion Island (L = 2.6). Over time the spectral structure of the chorus transformed into a hiss band spanning the same frequency range. The observation of overlapping chorus and hiss suggests that Marion Island was close to the plasmapause at the time of this event, and provides ground-based observational confirmation of the generation mechanism of plasmaspheric hiss from chorus waves outside of the plasmasphere. Chorus observations at Marion Island were not common during this period of the solar cycle and so this event was investigated in detail. The geomagnetic conditions are discussed and geosynchronous particle data and broadband data from two other stations are presented. Empirical models are employed to predict the location of the plasmapause, and its location is inferred from a knee whistler recorded at Dunedin, New Zealand. These show that Marion Island is in the vicinity of the plasmapause during the event. The event is also compared to chorus observed at similar L after the Halloween storms of 2003. The rarity of the chorus observation is quantified using DEMETER VLF data. The DEMETER data, along with the various ground based VLF measurements, allows us to infer temporal and spatial variations in the chorus source region.
Fichier principal
Vignette du fichier
Delport_et_al-2012-Journal_of_Geophysical_Research__Space_Physics_(1978_2012).pdf (3 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

insu-01179533 , version 1 (22-07-2015)



B Delport, A.B. Collier, J Lichtenberger, C.J. Rodger, Michel Parrot, et al.. Simultaneous observation of chorus and hiss near the plasmapause. Journal of Geophysical Research: Atmospheres, 2012, 117, A12218 (17 p.). ⟨10.1029/2012JA017609⟩. ⟨insu-01179533⟩
140 View
132 Download



Gmail Facebook Twitter LinkedIn More