Cluster observations of trapped ions interacting with magnetosheath mirror modes

0360932 - ÚFA 2012 RIV DE eng J - Journal Article
Souček, Jan - Escoubet, C. P.
Cluster observations of trapped ions interacting with magnetosheath mirror modes.
Annales Geophysicae. Roč. 29, - (2011), s. 1049-1060. ISSN 0992-7689. E-ISSN 1432-0576
Institutional research plan: CEZ:AV0Z30420517
Keywords : mirror mode waves * trapped particles * magnetosheath ions
Subject RIV: BL - Plasma and Gas Discharge Physics
Impact factor: 1.842, year: 2011
http://www.ann-geophys.net/29/1049/2011/angeo-29-1049-2011.pdf

Mirror modes are among the most intense low frequency plasma wave phenomena observed in the magnetosheaths of magnetized planets. They appear as large amplitude non-propagating fluctuations in the magnetic field magnitude and plasma density. These structures are widely accepted to represent a non-linear stage of the mirror instability, dominant in plasmas with large ion beta and a significant ion temperature anisotropy. It has long been recognized that the mirror instability both in the linear and non-linear stage is a kinetic process and that the behavior of resonant particles at small parallel velocities is crucial for its development and saturation. In this work we used data from the Cluster spacecraft to perform the first detailed experimental study of ion velocity distribution associated with mirror mode oscillations. We show a conclusive evidence for the predicted cooling of resonant ions at small parallel velocities and heating of trapped ions at intermediate pitch angles.
Permanent Link: http://hdl.handle.net/11104/0198370