标题： 钱德拉对新发现的磁星Swift J1818.0-1607的观测 显示英文标题

标题： Chandra observations of the newly discovered magnetar Swift J1818.0-1607

摘要： Swift J1818.0-1607 是由 Swift 爆发警报望远镜于 2020 年 3 月 12 日发现的一颗新射电明亮磁星。 它的磁场强度约为 B~2.5e14 G，转速下降的光度为 7.2e35 ergs/s，特征年龄约为 470 年。 在这里我们报告了对 Swift J1818.0-1607 的 Chandra 观测结果，这些观测使得对该磁星及其环境进行了高分辨率成像和光谱研究。 磁星的 1-10 keV 能谱可以用一个单一的黑体模型很好地描述，该模型具有 1.2\pm 0.1 keV 的温度和未吸收的通量为 1.9e-11 ergs/cm^2/s。 这意味着在 6.5 千秒的距离上 X 射线光度约为 ~9.6e34 ergs/s，效率约为 0.13。 Chandra 图像还显示从磁星向外延伸超过 10" 的微弱弥散发射，其能谱可以用一个光子指数为 2.0\pm 0.5 和光度为 ~8.1e33 ergs/s 的幂律模型很好地描述。 扩展发射很可能主要由尘埃散射晕主导，未来对该源在平静状态下的观测将揭示任何潜在的紧凑风星云。 我们得出结论，Swift J1818.0-1607 是一种表现出高 B 脉冲星和磁星之间特性的瞬变源，至少部分地由其高转速下降提供能量，类似于旋转供能的脉冲星。 显示英文摘要

摘要： Swift J1818.0-1607 is a new radio-loud magnetar discovered by the Swift Burst Alert Telescope on 2020 March 12. It has a magnetic field B~2.5e14 G, spin-down luminosity of 7.2e35 ergs/s, and characteristic age of ~470yr. Here we report on the Chandra observations of Swift J1818.0-1607, which allowed for a high-resolution imaging and spectroscopic study of the magnetar and its environment. The 1-10 keV spectrum of the magnetar is best described by a single blackbody model with a temperature of 1.2\pm0.1 keV and an unabsorbed flux of 1.9e-11 ergs/cm^2/s. This implies an X-ray luminosity of ~9.6e34 ergs/s and an efficiency of ~0.13 at a distance of 6.5 kpc. The Chandra image also shows faint diffuse emission out to >10" from the magnetar, with its spectrum adequately described by a powerlaw with a photon index of 2.0\pm0.5 and a luminosity of ~8.1e33 ergs/s. The extended emission is likely dominated by a dust scattering halo and future observations of the source in quiescence will reveal any underlying compact wind nebula. We conclude that Swift J1818.0-1607 is a transient source showing properties between high-B pulsars and magnetars, and could be powered at least partly by its high spin-down similar to the rotation-powered pulsars.