Width dependent collisionless electron dynamics in the static fields of the shock ramp, 2, Phase space portrait

Nonlinear Processes in Geophysics

M. A. Balikhin²  U. Griv¹  M. Gedalin¹ 

[1] Ben-Gurion University, Beer-Sheva, Israel;Sheffield University, Sheffield, England

Others  :  1006581
DOI  :  doi:10.5194/npg-4-173-1997

【 摘 要 】

We study numerically in detail the behaviour of electrons in thestrongly inhomogeneous static magnetic and electric fields, which are typical for thinquasiperpendicular collisionless shocks. We pay particular attention to the dependence ofthe final electron velocities on their initial velocities, for different shock widths.Electrons are completely magnetized when the shock is wide, but becomedemagnetized, andthe energies that they acquire rapidly increase with the steepening of the fieldstructure. One of the clear manifestations of the electron demagnetization is the loss ofeven approximate one-to-one correspondence of the downstream perpendicular velocity to theupstream perpendicular velocity. Electron reflection occurs despite the large cross-shockpotential which accelerates electrons along the magnetic field (the regime of complete magnetization) or across the shock (strong demagnetization). The reflected ion fraction is sensitive to the potential,magnetic field jump, and ramp width.

【 授权许可】

   
© Author(s) 1997. This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 License.