相对论电子在无规磁场中运动的新发射光谱
A Novel Emission Spectrum From A Relativistic Electron Moving In A Random Magnetic Field
摘要：
本文数值计算了高能天体物理源中小尺度湍流磁场中相对论电子的辐射谱。这种辐射谱由强度参数$a = λ_{B}} e|B|/mc^2$表征，其中$λ_{B}}$是湍流场的长度尺度。当$a$远大于辐射电子$γ$的洛伦兹因子时，实现同步辐射，而$a\ll 1$对应于所谓的抖动辐射状态。因为对于$1<a<γ$我们不能使用任何一种近似，我们应该求助于Lienard-Wiechert势来计算辐射谱，这在本文中进行。我们假设柯尔莫哥洛夫湍流产生随机磁场，注入单能电子，求解运动方程，并计算辐射谱。我们用$γ= 10$对$a$的几个值进行了数值计算。我们得到了各种类型的光谱范围之间的抖动辐射和同步辐射。对于$a\sim 7$，光谱呈现出一种新的形状，这一点迄今为止还没有被注意到。它在中能区类似于同步加速器谱，但在低频区它是破幂律的，而在高频区在同步加速器截止之外出现额外的幂律分量。我们给出了这些特征的物理解释。
英文摘要：
We calculate numerically the radiation spectrum from relativistic electrons moving in small scale turbulent magnetic fields expected in high energy astrophysical sources. Such radiation spectrum is characterized by the strength parameter $a = λ_{B}} e|B|/mc^2$, where $λ_{B}}$ is the length scale of the turbulent field. When $a$ is much larger than the Lorentz factor of a radiating electron $γ$, synchrotron radiation is realized, while $a\ll 1$ corresponds to the so-called jitter radiation regime. Because for $1<a<γ$ we cannot use either approximations, we should have recourse to the Lienard-Wiechert potential to evaluate the radiation spectrum, which is performed in this paper. We generate random magnetic fields assuming Kolmogorov turbulence, inject monoenergetic electrons, solve the equation of motion, and calculate the radiation spectrum. We perform numerical calculations for several values of $a$ with $γ= 10$. We obtain various types of spectra ranging between jitter radiation and synchrotron radiation. For $a\sim 7$, the spectrum turns out to take a novel shape which has not been noticed up to now. It is like a synchrotron spectrum in the middle energy region, but in the low frequency region it is a broken power law and in the high frequency region an extra power law component appears beyond the synchrotron cutoff. We give a physical explanation of these features.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
