论文标题
垂直冲击的快速颗粒加速度，上游磁场均匀且下游湍流
Fast Particle Acceleration at Perpendicular Shocks with Uniform Upstream Magnetic Field and Strong Downstream Turbulence
论文作者
论文摘要
冲击波通过扩散的冲击加速器（DSA）机制产生相对论颗粒。在各种情况下，预计垂直冲击已经快速加速。我们研究了在垂直冲击下加速的颗粒的加速度和能量光谱。在我们的模型中，上游垂直磁场没有波动，并且下游区域高度湍流。然后，粒子运动是上游区域中的回旋，下游的BOHM样扩散。在这种情况下，我们得出了加速时间的分析形式。使用测试粒子模拟，验证了我们公式的有效性。另外，颗粒的能谱与标准DSA预测的能量相同。因此，目前提出的机制同时意识到快速加速度和规范频谱，即$ dn/dp \ propto p^{ - 2} $，即使没有上游磁化放大。
The shock waves produce relativistic particles via the diffusive shock acceleration (DSA) mechanism. Among various circumstances, fast acceleration has been expected for perpendicular shocks. We investigate the acceleration time and the energy spectrum of particles accelerated at a perpendicular shock. In our model, the upstream perpendicular magnetic field has no fluctuation, and the downstream region is highly turbulent. Then, the particle motion is the gyration in the upstream region and Bohm-like diffusion downstream. Under this situation, we derive an analytical form of the acceleration time. Using test particle simulations, the validity of our formula is verified. In addition, the energy spectrum of particles is the same as those predicted by standard DSA. Therefore, presently proposed mechanism simultaneously realizes the rapid acceleration and the canonical spectrum, $dN/dp \propto p^{-2}$, even if there is no upstream magnetic amplification.
