质子束尾波场中利用密度跃变实现电子捕获及加速的粒子模拟

Particle simulation of plasma electron trapping and acceleration in proton driven plasma wakefield using density transition

摘要: 用2D3V粒子模拟程序研究了高能质子束驱动的尾波场加速电子的方案，及其在此方案中应用背景等离子体密度的跃变致使等离子体电子自注入加速相区的可能性。粒子模拟结果显示:密度跃变实现了电子的自注入，并且捕获的电子束处于加速相位，等离子体尾波场纵向电场对捕获的电子束起箍缩作用；捕获的电子束随着传输，表现为窄能谱分布；同时随着密度跃变大小的增大，可以增加等离子体电子的捕获。

Abstract: Numerical simulations are conducted on the scheme of energetic proton-bunch driven plasma wakefield acceleration and the possibility of the selfinjection scenario in proton-bunch driven plasma wakefield acceleration by using a density transition of plasma with the help of 2D3V PIC code. The simulations show that enhanced selfinjection of electrons in the scenario is realized successfully. It is found that the number of trapped particles increases as the amplitude of density transition increases．