发表机构
National Science Center Kharkiv Institute of Physics and Technology（哈尔科夫物理技术国家科学中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文通过2.5D粒子云模拟研究过渡层对分层等离子体波导中正电子尾场加速的影响，发现过渡层厚度超过趋肤深度时加速率显著降低，并提出参数修正方法以补偿能量增益下降并保证稳定输运。
AI 中文摘要
利用2.5维粒子云模拟，我们研究了在两层不同密度均匀等离子体之间存在过渡层（TL）的分层等离子体波导（LPW）中，正电子和电子的等离子体尾场加速器（PWFA）参数。分层等离子体被建模为近壁面高密度管状等离子体与轴上密度显著较低的等离子体柱的组合，两者之间由过渡层分隔，在过渡层中，等离子体密度根据特定规律从低值平滑过渡到高值。研究表明，当存在过渡层时，使用为无过渡层的分层等离子体波导确定的PWFA参数会改变加速条件，且这种改变取决于过渡层的厚度。实验证明，当过渡层厚度超过管状等离子体中的趋肤层深度时，正电子加速率显著降低。本文提出了修正所考虑的等离子体波导参数的方法，以补偿加速束团能量增益的下降并确保其稳定输运。
英文摘要
Using 2.5D particle-in-cell simulations, we investigate the parameters of a plasma wakefield accelerator (PWFA) for positrons and electrons in a layered plasma waveguide (LPW) in the presence of a transition layer (TL) between two layers of uniform plasma with different densities. The layered plasma is modeled as a combination of a near-wall tubular plasma of higher density and an on-axis plasma column of substantially lower density, separated by a TL in which the plasma density varies smoothly from the lower to the higher value according to a specified law. It is shown that using the PWFA parameters determined for a layered plasma waveguide without the transition layer changes the acceleration conditions when the TL is present, and that this change depends on the TL thickness. It is demonstrated that when the TL thickness exceeds the skin-layer depth in the tubular plasma, the positron acceleration rate decreases substantially. The methods are proposed for correcting the parameters of the plasma waveguide under consideration that compensate for the decrease in the energy gain of the accelerated bunches and ensure their stable transport.
