论文标题
Magnetar Swift J1818.0-1607的长期收音机和X射线演变
Long term radio and X-ray evolution of the magnetar Swift J1818.0-1607
论文作者
论文摘要
我们在一年的时间内报道了看似最年轻的Magnetar Swift的长期监测活动〜J1818.0-1607。在同一时间跨度上，我们获得了磁铁的连贯的时机解决方案。磁体的频率导数显示系统变化，值的振荡大约$ -1.37 $ \ times $ 10 $^{ - 11} $ hz s $^{ - 1} $。在平均值上收敛之前，频率导数的变化大小会随时间减少。我们能够识别自旋频导数中的四个状态，这些状态是通过对平均值的调制量进行量化的，这些状态与这些状态之间的过渡似乎与磁盘无线电发射的变化相关，而在较短时间范围（天）上平均无线电分布变化中没有相关性。 0.5--12 KEV X射线通量显示出单调的减小，这可以归因于中子恒星表面的热点的热发射，该恒星的大小降低。这种下降与其他磁铁中看到的相一致。无线电发射模式与旋转速率的行为之间的潜在相关性暗示了类似于模式变化无线电脉冲星的子集的磁力磁场的全局变化，并提出了两个子组合之间的物理联系。
We report on the the long term monitoring campaign of the seemingly youngest magnetar Swift~J1818.0-1607 at radio and X-ray wavelengths over a span of one year. We obtained a coherent timing solution for the magnetar over the same time span. The frequency derivative of the magnetar shows systematic variation with the values oscillating about a mean value of $-$1.37$\times$10$^{-11}$ Hz s$^{-1}$. The magnitude of the variation in the frequency derivative reduces with time before converging on the mean value. We were able to identify four states in the spin-frequency derivative that were quantified by the amount of modulation about the mean value and the transition between these states seem to be correlated with the change in the radio emission of the magnetar while no correlation is seen in the average radio profile variability on a shorter timescale (days). The 0.5--12 keV X-ray flux shows a monotonic decrease that can be attributed to thermal emission from a hot-spot on the surface of the neutron star that is reducing in size. Such decrease is consistent with what is seen in other magnetars. The potential correlation between the radio emission mode and the behaviour of the spin-down rate hints to a global change in the magnetopshere of the magnetar akin to the correlation seen in a subset of mode-changing radio pulsars and suggests a physical link between the two sub-populations.
