论文标题
宇宙射线对介质周围介质的动力效果
Dynamical Effects of Cosmic Rays on the Medium Surrounding Their Sources
论文作者
论文摘要
宇宙射线（CRS）主要沿着局部磁场留下来源；这样一来，他们通过流媒体不稳定性激发了共鸣和非谐振模式。这些模式的激发导致散射增强，进而导致大压力梯度，导致气体，CRS和自生生成的磁场的气泡形成，这些磁场扩展到星际介质中。通过混合粒子中的模拟，我们表明，通过刺激非谐振不稳定性，CRS在其源周围挖掘了一个强烈抑制扩散率的腔。这一发现使迄今为止采用的通量管假设无效，在该假设下，颗粒即使在非线性方向上也沿磁线移动。这种现象是一般的，有望发生在银河系中任何足够强大的CR源周围。我们的结果可能会提供对众多抑制CR扩散的众多主张，例如超新星残留物，脉冲星风星和恒星簇的众多主张。
Cosmic rays (CRs) leave their sources mainly along the local magnetic field; in doing so they excite both resonant and nonresonant modes through streaming instabilities. The excitation of these modes leads to enhanced scattering and in turn to a large pressure gradient that causes the formation of bubbles of gas, CRs, and self-generated magnetic fields expanding into the interstellar medium. By means of hybrid Particle-In-Cell simulations, we show that, by exciting the nonresonant instability, CRs excavate a cavity around their source where the diffusivity is strongly suppressed. This finding invalidates the so far largely adopted flux-tube assumption, under which particles move along magnetic lines even in the nonlinear regime. This phenomenon is general and is expected to occur around any sufficiently powerful CR source in the Galaxy. Our results might provide a physical explanation of the numerous claims of suppressed CR diffusion around Galactic sources such as supernova remnants, pulsar wind nebulae, and stellar clusters.
