论文标题
具有强辐射反应的超级电荷颗粒的动力学。 I.亚里士多德平衡状态
Dynamics of ultrarelativistic charged particles with strong radiation reaction. I. Aristotelian equilibrium state
论文作者
论文摘要
天体物理学和激光物理群落的先前研究已经确定了一种有趣的现象，其中经历强辐射反应的超偏移电荷颗粒倾向于沿局部电磁场固定的特殊方向移动。在相对论文献中，这些被称为麦克斯韦场的“主要无空方向”（PNDS）。该制度中的粒子具有“亚里士多德”动力学，因为其速度（而不是加速度）由局部场确定。我们从Landau-Lifshitz方程式开始，研究了这个亚里士多德的平衡，从描述了带电的颗粒运动，包括辐射反应。使用适合PND的Frenet-Serret框架，我们得出了描述沿本地PND运动的Lorentz因子，以及漂移速度，反映了从一个PND到另一个PND的较慢。我们得出在现场配置上的条件，这对于发生这种平衡是必需的。我们证明了我们的分析公式与适当制度中Landau-Lifshitz方程的完整数值解有关我们的分析公式的一致性。
Previous studies from the astrophysics and laser physics communities have identified an interesting phenomenon wherein ultrarelativistic charged particles experiencing strong radiation reaction tend to move along special directions fixed by the local electromagnetic field. In the relativity literature these are known as the "principal null directions" (PNDs) of the Maxwell field. A particle in this regime has "Aristotelian" dynamics in the sense that its velocity (rather than acceleration) is determined by the local field. We study this Aristotelian equilibrium in detail, starting from the Landau-Lifshitz equation describing charged particle motion including radiation reaction. Using a Frenet-Serret frame adapted to the PNDs, we derive the Lorentz factor describing motion along the local PND, together with drift velocities reflecting slower passage from one PND to another. We derive conditions on the field configuration that are necessary for such an equilibrium to occur. We demonstrate agreement of our analytic formulas with full numerical solutions of the Landau-Lifshitz equation in the appropriate regime.
