We study with a one-dimensional particle-in-cell (PIC) simulation the expansion of a pair cloud into a magnetized electron-proton plasma as well as the formation and subsequent propagation of a tangential discontinuity that separates both plasmas. Its propagation speed takes the value that balances the magnetic pressure of the discontinuity against the thermal pressure of the pair cloud and the ram pressure of the protons. Protons are accelerated by the discontinuity to a speed that exceeds the fast magnetosonic speed by the factor 10. A supercritical fast magnetosonic shock forms at the front of this beam. An increasing proton temperature downstream of the shock and ahead of the discontinuity leaves the latter intact. We create the discontinuity by injecting a pair cloud at a simulation boundary into a uniform electron-proton plasma, which is permeated by a perpendicular magnetic field. Collisionless tangential discontinuities in the relativistic pair jets of X-ray binaries (microquasars) are in permanent contact with the relativistic leptons of its inner cocoon and they become sources of radio synchrotron emissions.

中文翻译：

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对等离子体和电子-质子等离子体之间的无碰撞切向不连续性

我们使用一维粒子胞内粒子 (PIC) 模拟研究一对云扩展为磁化电子-质子等离子体，以及分离两种等离子体的切向不连续性的形成和随后的传播。它的传播速度取平衡不连续性的磁压力与对云的热压力和质子的撞击压力的值。质子被不连续性加速到超过快速磁超声速度 10 倍的速度。在该光束的前端形成超临界快速磁超声冲击。激波下游和不连续性之前的质子温度升高，使后者完好无损。我们通过在模拟边界处将一对云注入均匀的电子 - 质子等离子体中来创建不连续性，它被垂直磁场所渗透。X射线双星（微类星体）的相对论对射流中的无碰撞切向不连续性与其内部茧的相对论轻子永久接触，它们成为无线电同步加速器发射的来源。