There is a new effect that can limit the lifetime of a weakly non-linear wakefield in a radially bounded plasma. If the drive beam is narrow, some of the plasma electrons fall out of the collective motion and leave the plasma radially, forming a negatively charged halo around it. These electrons repeatedly return to the plasma under the action of the charge separation field, interact with the plasma wave and cause its damping. The lowest-energy halo electrons take the energy from the wave more efficiently, because their trajectories are bent by the plasma wave towards the regions of the strongest acceleration. For correct accounting of the wave damping in simulations, it is necessary to take the simulation window at least twice as wide as the plasma.

有一种新效应可以限制径向有界等离子体中弱非线性尾流场的寿命。如果驱动光束很窄，一些等离子体电子会从集体运动中落下并径向离开等离子体，在它周围形成一个带负电的光晕。这些电子在电荷分离场的作用下反复返回等离子体，与等离子体波相互作用并使其衰减。能量最低的晕电子更有效地从波中获取能量，因为它们的轨迹被等离子体波弯曲到加速最强的区域。为了正确计算模拟中的波阻尼，有必要使模拟窗口至少是等离子体的两倍宽。