On the numerical modelling of VLF chorus dynamical spectra

0332612 - ÚFA 2010 RIV US eng J - Journal Article
Nunn, D. - Santolík, Ondřej - Rycroft, M. - Trakhtengerts, V.
On the numerical modelling of VLF chorus dynamical spectra.
[Numerické modelování dynamického spektra emisí typu chorus.]
Annales Geophysicae. Roč. 27, č. 6 (2009), s. 2341-2359. ISSN 0992-7689. E-ISSN 1432-0576
R&D Projects: GA ČR GA205/06/1267
Institutional research plan: CEZ:AV0Z30420517
Keywords : chorus * numerical modelling
Subject RIV: BL - Plasma and Gas Discharge Physics
Impact factor: 1.648, year: 2009
http://www.ann-geophys.net/27/2341/2009/

This paper presents a study of the use of a one-dimensional Vlasov Hybrid Simulation (VHS) computer code to simulate the dynamical spectra (I.e. Frequency versus time spectrograms) of ELF/VLF chorus signals (from a fraction to 10 kHz). Recently excellent measurements of chorus have been made in the source region close to the geomagnetic equator aboard the four spacecraft Cluster mission. Using Cluster data for wave amplitude, which is up to 300 pT, local gyrofrequency, cold plasma density, and Lshell, observed chorus signals are reproduced with remarkable fidelity and, in particular, sweep rates in the range 1–10 kHz result as observed. Further, we find that the sweep rate is a falling function of increasing cold plasma density, again in accord with observations. Finally, we have satisfactorily simulated the rather rare falling frequency elements of chorus which are sometimes observed aboard Cluster in the generation region.

Numerické modelování dynamického spektra emisí typu chorus za využití jednorozměrné Vlasovovy hybridní simulace.
Permanent Link: http://hdl.handle.net/11104/0177823