论文标题
以Maxi J1421-613为中心的环形X射线发射的发现：粉尘散射X射线？
Discovery of annular X-ray emission centered on MAXI J1421-613: Dust-scattering X-rays?
论文作者
论文摘要
我们报告了在Suzaku的后续分析中，在瞬态源的中心（X射线Burster Maxi J1421-613）周围发现了$ \ sim $ 3'-9'半径的环形发射。环形发射的光谱没有明显的发射线结构，并通过吸收的功率定律模型很好地解释了$ \ sim $ 4.2的光子指数。这些特征不包括环形发射是超新星残留物的壳状成分的可能性。光谱形状，时间历史和环形发射的X射线通量与发射是由于尘埃落冰的回声所致的情况。环形发射是在粉尘散射的罕见状态下进行的，其中中央X射线源Maxi J1421-613在短时间爆发中，带有三个X射线爆发，并立即重新进入了很长的静态时期。沿环形发射的氢柱密度的分布遵循CO强度的分布，这意味着Maxi J1421-613位于CO云后面。我们估计，至Maxi J1421-613的距离为$ \ sim $ 3〜kpc，假设负责环形发射的灰尘层与CO云的位置相同。
We report the discovery of an annular emission of $\sim$3'-9' radius around the center of a transient source, an X-ray burster MAXI J1421-613, in the Suzaku follow-up analysis. The spectrum of the annular emission shows no significant emission-line structure, and is well explained by an absorbed power law model with a photon index of $\sim$4.2. These features exclude the possibility that the annular emission is a shell-like component of a supernova remnant. The spectral shape, the time history, and the X-ray flux of the annular emission agree with the scenario that the emission is due to a dust-scattering echo. The annular emission is made under a rare condition of the dust-scattering echo, where the central X-ray source, MAXI J1421-613, exhibits a short time outburst with three X-ray bursts and immediately re-enters a long quiescent period. The distribution of the hydrogen column density along the annular emission follows that of the CO intensity, which means that MAXI J1421-613 is located behind the CO cloud. We estimate the distance to MAXI J1421-613 to be $\sim$3~kpc assuming that the dust layer responsible for the annular emission is located at the same position as the CO cloud.
