Medvedev 2007 伽玛暴余辉的jitter模型
主要内容:
模仿同步辐射的余辉模型，认为磁场是一个分布而不是同步辐射模型所假设的为常量（也就是说磁场从微观上也是小尺度的，而没有一个对同步辐射负责的大尺度磁场，虽然在标准模型中大尺度磁场在整个激波看来也是杂乱无章、各向同性的），考虑Weibel不稳定以及数值模拟计算出来的波矢k，计算辐射的流量和谱。
（这样的一个推论应该是没有偏振了哦。）
精彩摘抄:
文章信息:
Jitter radiation as a possible mechanism for Gamma-Ray Burst afterglows. Spectra and lightcurves
(Submitted on 9 Mar 2007)
Abstract: The standard model of GRB afterglows assumes that the radiation observed as a delayed emission is of synchrotron origin, which requires the shock magnetic field to be relatively homogeneous on small scales. An alternative mechanism -- jitter radiation, which traditionally has been applied to the prompt emission -- substitutes synchrotron when the magnetic field is tangled on a microscopic scale. Such fields are produced at relativistic shocks by the Weibel instability. Here we explore the possibility that small-scale fields populate afterglow shocks. We derive the spectrum of jitter radiation under the afterglow conditions. We also derive the afterglow lightcurves for the ISM and Wind profiles of the ambient density. Jitter self-absorption is calculated here for the first time. We find that jitter radiation can produce afterglows similar to synchrotron-generated ones, but with some important differences. We compare the predictions of the two emission mechanisms. By fitting observational data to the synchrotron and jitter afterglow lightcurves, it can be possible to discriminate between the small-scale vs large-scale magnetic field models in afterglow shocks.
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