Non-adiabatic electron behaviour due to short-scale electric field structures at collisionless shock waves

Autor: V. See, R. F. Cameron, S. J. Schwartz
Jazyk: angličtina
Rok vydání: 2013
Předmět:
Zdroj: Annales Geophysicae, Vol 31, Pp 639-646 (2013)
Druh dokumentu: article
ISSN: 0992-7689
1432-0576
DOI: 10.5194/angeo-31-639-2013
Popis: Under sufficiently high electric field gradients, electron behaviour within exactly perpendicular shocks is unstable to the so-called trajectory instability. We extend previous work paying special attention to short-scale, high-amplitude structures as observed within the electric field profile. Via test particle simulations, we show that such structures can cause the electron distribution to heat in a manner that violates conservation of the first adiabatic invariant. This is the case even if the overall shock width is larger than the upstream electron gyroradius. The spatial distance over which these structures occur therefore constitutes a new scale length relevant to the shock heating problem. Furthermore, we find that the spatial location of the short-scale structure is important in determining the total effect of non-adiabatic behaviour – a result that has not been previously noted.
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