The Dynamic Quasiperpendicular Shock: Cluster Discoveries

0393010 - ÚFA 2014 RIV NL eng J - Článek v odborném periodiku
Krasnoselskikh, V. - Balikhin, M. - Walker, S. N. - Schwartz, S. - Sundkvist, D. - Lobzin, V. - Gedalin, M. - Bale, S. D. - Mozer, F. - Souček, Jan - Hobara, Y. - Comisel, H.
The Dynamic Quasiperpendicular Shock: Cluster Discoveries.
Space Science Reviews. Roč. 178, 2-4 (2013), s. 535-598. ISSN 0038-6308. E-ISSN 1572-9672
Institucionální podpora: RVO:68378289
Klíčová slova: collisionless shocks * waves in plasmas * nonstationarity * shock scales * plasma heating and acceleration * wave-particle interactions
Kód oboru RIV: BL - Fyzika plazmatu a výboje v plynech
Impakt faktor: 5.874, rok: 2013
http://link.springer.com/article/10.1007%2Fs11214-013-9972-y

The energy repartition amongst particle populations in quasiperpendicular shocks is a multi-scale process related to the spatial and temporal structure of the electromagnetic fields within the shock layer. The most important processes take place in the close vicinity of the major magnetic transition or ramp region. The distribution of electromagnetic fields in this region determines the characteristics of ion reflection and thus defines the conditions for ion heating and energy dissipation for supercritical shocks and also the region where an important part of electron heating takes place. In other words, the ramp region determines the main characteristics of energy repartition. All these processes are crucially dependent upon the characteristic spatial scales of the ramp and foot region provided that the shock is stationary. The process of shock formation consists of the steepening of a large amplitude nonlinear wave. At some point in its evolution the steepening is arrested by processes occurring within the shock transition. From the earliest studies of collisionless shocks these processes were identified as nonlinearity, dissipation, and dispersion. Their relative role determines the scales of electric and magnetic fields, and so control the characteristics of processes such as ion reflection, electron heating and particle acceleration. The purpose of this review is to address a subset of unresolved problems in collisionless shock physics from experimental point of view making usemulti-point observations onboard Cluster satellites. The problems we address are determination of scales of fields and of a scale of electron heating, identification of energy source of precursor wave train, an estimate of the role of anomalous resistivity in energy dissipation process by means of measuring short scale wave fields, and direct observation of reformation process during one single shock front crossing.
Trvalý link: http://hdl.handle.net/11104/0221771