Skip to Main content Skip to Navigation
Journal articles

Heating of proton conics by resonant absorption in a multicomponent plasma: 1. Experimental evidence

Abstract : ELF emissions observed on the low‐altitude AUREOL 3 satellite are seen in association with H+ ions at large pitch angle. The flux in the upward direction for ∼120° pitch angle is found to be equal to or larger than the flux at ∼60° pitch angle, which provides evidence for transverse acceleration at or below the spacecraft. These emissions have a sharp lower‐frequency cutoff of the transverse components of the electric field and a narrow peak at, or, more precisely, just below the proton gyrofrequency fH+. This narrow peak is more easily seen on the parallel component and appears as a narrow line on the spectrogram of this component. A statistical study of the occurrence of this line at f ∼ fH+ is presented. It is shown that this line is observed at relatively high invariant latitude within the light ion trough where a strong depletion of thermal H+ ions occurs. Detailed analysis of ELF waves observed just below fH+ demonstrates that they propagate in the left‐hand mode. These observations are interpreted as a signature of mode conversion from a fast magnetosonic mode into a slow proton cyclotron mode. It is suggested that this slow proton cyclotron wave can accelerate protons up to a few hundreds electron volts in the transverse direction. This mode conversion process can operate over a much broader of large altitude range than covered by AUREOL 3; it is a likely candidate for explaining the formation of H+ conics. Theoretical calculations that support the above conclusions are given in a companion paper by Le Quéau et al. (this issue).
Complete list of metadata

Cited literature [51 references]  Display  Hide  Download
Contributor : Nathalie POTHIER Connect in order to contact the contributor
Submitted on : Tuesday, May 19, 2020 - 9:01:01 AM
Last modification on : Wednesday, June 1, 2022 - 5:18:18 AM


Publisher files allowed on an open archive




Jean-Louis Rauch, François Lefeuvre, Dominique Le Quéau, Alain Roux, Jean-Michel Bosqued, et al.. Heating of proton conics by resonant absorption in a multicomponent plasma: 1. Experimental evidence. Journal of Geophysical Research Space Physics, American Geophysical Union/Wiley, 1993, 98 (A8), pp.13347-13361. ⟨10.1029/92JA02255⟩. ⟨insu-02612308⟩



Record views


Files downloads