GYROSURFING ACCELERATION OF IONS IN FRONT OF EARTH's QUASI-PARALLEL BOW SHOCK

Abstract : It is well known that shocks in space plasmas can accelerate particles to high energies. However, many details of the shock acceleration mechanism are still unknown. A critical element of shock acceleration is the injection problem; i.e., the presence of the so called seed particle population that is needed for the acceleration to work efficiently. In our case study, we present for the first time observational evidence of gyroresonant surfing acceleration in front of Earth's quasi-parallel bow shock resulting in the appearance of the long-suspected seed particle population. For our analysis, we use simultaneous multi-spacecraft measurements provided by the Cluster spacecraft ion (CIS), magnetic (FGM), and electric field and wave instrument (EFW) during a time period of large inter-spacecraft separation distance. The spacecraft were moving toward the bow shock and were situated in the foreshock region. The results show that the gyroresonance surfing acceleration takes place as a consequence of interaction between circularly polarized monochromatic (or quasi-monochromatic) transversal electromagnetic plasma waves and short large amplitude magnetic structures (SLAMSs). The magnetic mirror force of the SLAMS provides the resonant conditions for the ions trapped by the waves and results in the acceleration of ions. Since wave packets with circular polarization and different kinds of magnetic structures are very commonly observed in front of Earth's quasi-parallel bow shock, the gyroresonant surfing acceleration proves to be an important particle injection mechanism. We also show that seed ions are accelerated directly from the solar wind ion population. Key words: acceleration of particles – plasmas – shock waves – supernovae: general – waves Online-only material: color figures
Type de document :
Article dans une revue
The Astrophysical journal letters, Bristol : IOP Publishing, 2013, 771 (1), pp.4. 〈10.1088/0004-637X/771/1/4〉
Liste complète des métadonnées

Littérature citée [4 références]  Voir  Masquer  Télécharger

https://hal-insu.archives-ouvertes.fr/insu-01258093
Contributeur : Nathalie Pothier <>
Soumis le : lundi 18 janvier 2016 - 16:10:21
Dernière modification le : jeudi 7 février 2019 - 17:06:19
Document(s) archivé(s) le : vendredi 11 novembre 2016 - 10:06:41

Fichier

Kis-2013.pdf
Fichiers éditeurs autorisés sur une archive ouverte

Identifiants

Collections

Citation

Arpad Kis, Oleksiy Agapitov, Vladimir Krasnoselskikh, Yuri V. Khotyaintsev, Iannis Dandouras, et al.. GYROSURFING ACCELERATION OF IONS IN FRONT OF EARTH's QUASI-PARALLEL BOW SHOCK. The Astrophysical journal letters, Bristol : IOP Publishing, 2013, 771 (1), pp.4. 〈10.1088/0004-637X/771/1/4〉. 〈insu-01258093〉

Partager

Métriques

Consultations de la notice

215

Téléchargements de fichiers

83