论文标题
快速无线电爆发的移动镜模型
The Moving Mirror model for Fast Radio Bursts
论文作者
论文摘要
最近观察到蟹脉脉冲的相干辐射（Bij et al 2021）表明，发射是由超级主义（$γ\ sim 10^4 $），冷等离子体流动驱动的。相对扩展的等离子体壳可以像移动的镜像一样压缩环境磁场，因此产生的连贯的辐射的波长比环境介质的波长比$γ^2 $短。 Colgate和Noerdelinger（1971）过去已经在无线电大声的超新星爆炸的背景下研究了这种机制。在这项工作中，我们建议一种类似的机制在快速无线电爆发中驱动相干发射。高洛伦兹因子大大降低了隐含的能量和磁场需求，从而使常规（甚至是再生）的旋转能量旋转，快速旋转的脉冲星，而不是缓慢的旋转磁场来解释FRB。我们表明，该模型可以解释观察到的FRB的频率和时间演变，以及它们的持续时间，能量和不存在Panchromation对应物的频率和时间。我们还预测，随着观察时间的峰值频率下降为$ω_ {\ rm obs} \ propto t _ {\ rm obs}^{ - 1/2} $。不幸的是，使用当前功能，无法约束曲线的形状$ω_ {\ rm obs} \ left（t _ {\ rm obs} \ right）$。最后，我们发现该模型的变化可以解释较弱的无线电瞬变，例如从银河磁场观察到的瞬变。在此变体中，冲击波产生低频光子，然后将康普顿散布到GHz范围。
Recent observations of coherent radiation from the Crab pulsar (Bij et al 2021) suggest the emission is driven by an ultra - relativistic ($γ\sim 10^4$), cold plasma flow. A relativistically expanding plasma shell can compress the ambient magnetic field, like a moving mirror, and thus produce coherent radiation whose wavelength is shorter than that of the ambient medium by $γ^2$. This mechanism has been studied in the past by Colgate and Noerdelinger (1971), in the context of radio loud supernova explosions. In this work we propose that a similar mechanism drives the coherent emission in fast radio bursts. The high Lorenz factors dramatically lower the implied energy and magnetic field requirements, allowing the spin down energy of regular (or even recycled), fast spinning pulsars, rather than slow spinning magnetars, to explain FRBs. We show that this model can explain the frequency and the time evolution of observed FRBs, as well as their duration, energetics and absence of panchromatic counterparts. We also predict that the peak frequency of sub pulses decline with observation time as $ω_{\rm obs} \propto t_{\rm obs}^{-1/2}$. Unfortunately, with current capabilities it is not possible to constrain the shape of the curve $ω_{\rm obs} \left(t_{\rm obs} \right)$. Finally, we find that a variation of this model can explain weaker radio transients, such as the one observed from a galactic magnetar. In this variant, the shock wave produces low frequency photons which are then Compton scattered to the GHz range.
