On Particle Acceleration around Shocks. I.
On Particle Acceleration around Shocks. I.
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关于冲击周围的粒子加速。
DOI：
10.1086/375534
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
M. Vietri
中科院分区：
文献类型：
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作者：
M. Vietri
我们导出了激波加速的粒子分布函数的相对论协变方程(虽然不是很明显)，它也适用于极端相对论激波和任意各向异性粒子分布。该理论适用于任意俯仰角的散射，并通过福克-普朗克近似简化为众所周知的小角度散射的情形。问题的边界条件被完全重新表述，引入了物理激励的格林函数；新的表述允许以精确的方式导出靠近和远离注入能量的粒子谱，同时可以证明它在大粒子能量时归结为幂定律。用一种新的方法恢复了粒子的光谱指数。接触是与牛顿疗法相联系的。
We derive a relativistically covariant (although not manifestly so) equation for the distribution function of particles accelerated at shocks, which applies also to extremely relativistic shocks and arbitrarily anisotropic particle distributions. The theory is formulated for arbitrary pitch-angle scattering and reduces to the well-known case for small-angle scatterings via a Fokker-Planck approximation. The boundary conditions for the problem are completely reformulated introducing a physically motivated Green's function; the new formulation allows derivation of the particle spectrum both close and far away from the injection energy in an exact way, while it can be shown to reduce to a power law at large particle energies. The particle spectral index is also recovered in a novel way. Contact is made with the Newtonian treatment.