Newman D L, Goldman M V, Ergun R E, Mangeney A
Center for Integrated Plasma Studies, University of Colorado at Boulder, Boulder, Colorado 80309, USA.
Phys Rev Lett. 2001 Dec 17;87(25):255001. doi: 10.1103/PhysRevLett.87.255001. Epub 2001 Nov 28.
Kinetic 1D simulations reveal that a weak density depression in a current-carrying plasma can lead to the formation of a strong potential ramp (double layer). The ramp and plasma turbulence it creates share many features with recent particle and field measurements in the auroral ionosphere. An electron beam accelerated by the ramp produces a series of propagating electron phase-space holes via a spatial two-stream instability. Electron heating associated with the formation and merging of these holes is found to influence the subsequent evolution of the potential ramp.
一维动力学模拟表明，载流等离子体中的弱密度凹陷会导致强电势斜坡（双层）的形成。该斜坡及其产生的等离子体湍流与最近在极光电离层中的粒子和场测量结果有许多共同特征。由斜坡加速的电子束通过空间双流不稳定性产生一系列传播的电子相空间空洞。发现与这些空洞的形成和合并相关的电子加热会影响电势斜坡的后续演化。
