论文标题
磁力爆发的发射和中子星星合并的前体
Emission of magnetar bursts and precursors of neutron star mergers
论文作者
论文摘要
可以通过在外部磁层中生长到非线性振幅的Alfvén波，$ΔB/b \ sim 1 $并触发磁重新连接来发出磁盘爆发。相似的磁耀斑应在磁化的中子星二元近近二元合并中发生准周期。在这两种情况下，磁耀斑中的快速耗散都会产生光学厚的$ e^\ pm $等离子体，与生成的辐射能相比，其热容量可以忽略不计。然后，磁耗散涉及光子粘度，并通过Compton阻力在重新连接区域的等离子体体积运动上起作用。所得组合过程的有效温度被自调节至数十千kev。生成的X射线发射是使用时间依赖性的辐射转移模拟计算的，该模拟遵循$ e^\ pm $ Pairs的创建以及光子的生产，组合和逃脱。模拟显示了耗散区域如何穿着$ e^\ pm $外套的衣服，以及如何通过辐射传递通过外套来塑造逃逸光谱。将结果与观察到的磁力爆发进行了比较，包括SGR 1935+2154的最新活性以及快速无线电爆发。对磁化中子星星合并的X射线前体进行了预测。
Magnetar bursts can be emitted by Alfvén waves growing in the outer magnetosphere to nonlinear amplitudes, $δB/B\sim 1$, and triggering magnetic reconnection. Similar magnetic flares should occur quasi-periodically in a magnetized neutron star binary nearing merger. In both cases, fast dissipation in the magnetic flare creates optically thick $e^\pm$ plasma, whose heat capacity is negligible compared with the generated radiation energy. Magnetic dissipation then involves photon viscosity and acts through Compton drag on the plasma bulk motions in the reconnection region. The effective temperature of the resulting Comptonization process is self-regulated to tens of keV. The generated X-ray emission is calculated using time-dependent radiative transfer simulations, which follow the creation of $e^\pm$ pairs and the production, Comptonization, and escape of photons. The simulations show how the dissipation region becomes dressed in an $e^\pm$ coat, and how the escaping spectrum is shaped by radiative transfer through the coat. The results are compared with observed magnetar bursts, including the recent activity of SGR 1935+2154 accompanied by a fast radio burst. Predictions are made for X-ray precursors of magnetized neutron star mergers.
