标题： 下游湍流由特殊相对论性激波云团相互作用驱动的性质 显示英文标题

标题： Property of downstream turbulence driven by the special relativistic shock-clump interaction

摘要： 三维相对论性磁流体动力学模拟用于研究相对论激波与多个云团相互作用产生的下游湍流特性。 我们通过执行亥姆霍兹分解来分析下游湍流的特性。 结果显示，与非相对论激波情况相反，相对论激波中压缩模式的振幅与涡旋模式的振幅相当。 此外，许多反射激波在下游区域传播。 压缩模式、涡旋模式、反射激波和增强的磁场强度取决于上游密度波动的幅度。 我们的模拟结果表明，伽马射线暴余辉中磁能与激波动能比值$\epsilon_B$的广泛分布是由于伽马射线暴环境的多样性。 此外，高能天体周围的密度不均匀性会影响加速粒子的谱，因为反射激波和湍流可以在激波下游区域注入并加速非热粒子。 本文还分析和讨论了下游量的概率分布、湍流的功率谱以及涡旋的生成。 显示英文摘要

摘要： Three-dimensional special relativistic magnetohydrodynamic simulations are performed to investigate properties of the downstream turbulence generated by the interaction between a relativistic shock wave and multiple clumps. We analyze the properties of the downstream turbulence by performing the Helmholtz decomposition. It is shown that, in contrast to the non-relativistic shock case, the amplitude of compressive modes is comparable to that of solenoidal modes for the relativistic shock. In addition, many reflected shocks propagate in the downstream region. The strength of the compressive mode, the solenoidal mode, the reflected shock waves, and the amplified magnetic field depend on the amplitude of the upstream density fluctuations. Our simulation results suggest that the wide distribution of the ratio of the magnetic energy to the shock kinetic energy, $\epsilon_B$, in gamma-ray burst afterglows is due to the diversity of the gamma-ray burst environment. Furthermore, the inhomogeneity of density around high-energy astrophysical objects affects the spectrum of accelerated particles because the reflected shock and turbulence can inject and accelerate non-thermal particles in the shock downstream region. The probability distribution of the downstream quantities, power spectra of turbulence, and vortex generation are also analyzed and discussed in this work.