论文标题
部分可观测时空混沌系统的无模型预测
Testing afterglow models of FRB 200428 with early post-burst observations of SGR 1935+2154
论文作者
论文摘要
我们介绍了2020年4月/5月的Magnetar SGR 1935+2154的活性发作的Lofar成像观察结果。我们将最早的无线电限制放置在持续发射之后，低亮度快速无线电爆发FRB 200428。我们还进行图像平面搜索以进行瞬态发射，并且在观察过程中找不到无线电耀斑。我们检查了文献中FRB后的无线电上限，并发现所有这些都与FRB 200428的同步体Maser休克模型解释所预测的多波长余辉一致。但是，早期的光学观察似乎排除了具有恒定密度电流媒体的余波模型的简单版本。我们表明，可以通过将模型适应类似风的环境来减轻这些约束，但仅适用于有限的参数范围。此外，我们建议当冲击不再是相对论时，余潮模型内发生了延迟非热粒子加速度，这对于检测其他银河系FRB的余气可能至关重要。我们还讨论了未来的观察策略，以通过快速无线电观察到银河磁铁和附近的FRB来验证磁层或Maser Shock FRB模型。
We present LOFAR imaging observations from the April/May 2020 active episode of magnetar SGR 1935+2154. We place the earliest radio limits on persistent emission following the low-luminosity fast radio burst FRB 200428 from the magnetar. We also perform an image-plane search for transient emission and find no radio flares during our observations. We examine post-FRB radio upper limits in the literature and find that all are consistent with the multi-wavelength afterglow predicted by the synchrotron maser shock model interpretation of FRB 200428. However, early optical observations appear to rule out the simple versions of the afterglow model with constant-density circumburst media. We show that these constraints may be mitigated by adapting the model for a wind-like environment, but only for a limited parameter range. In addition, we suggest that late-time non-thermal particle acceleration occurs within the afterglow model when the shock is no longer relativistic, which may prove vital for detecting afterglows from other Galactic FRBs. We also discuss future observing strategies for verifying either magnetospheric or maser shock FRB models via rapid radio observations of Galactic magnetars and nearby FRBs.
