Wachter S, Ramirez-Ruiz E, Dwarkadas V V, Kouveliotou C, Granot J, Patel S K, Figer D
Spitzer Science Center, California Institute of Technology, Pasadena, California 91125, USA.
Nature. 2008 May 29;453(7195):626-8. doi: 10.1038/nature06987.
Magnetars are a special class of slowly rotating (period approximately 5-12 s) neutron stars with extremely strong magnetic fields (>10(14 )G)--at least an order of magnitude larger than those of the 'normal' radio pulsars. The potential evolutionary links and differences between these two types of object are still unknown; recent studies, however, have provided circumstantial evidence connecting magnetars with very massive progenitor stars. Here we report the discovery of an infrared elliptical ring or shell surrounding the magnetar SGR 1900+14. The appearance and energetics of the ring are difficult to interpret within the framework of the progenitor's stellar mass loss or the subsequent evolution of the supernova remnant. We suggest instead that a dust-free cavity was produced in the magnetar environment by the giant flare emitted by the source in August 1998. Considering the total energy released in the flare, the theoretical dust-destruction radius matches well with the observed dimensions of the ring. We conclude that SGR 1900+14 is unambiguously associated with a cluster of massive stars, thereby solidifying the link between magnetars and massive stars.
磁星是一类特殊的缓慢旋转（周期约为5 - 12秒）的中子星，其具有极强的磁场（>10¹⁴高斯）——至少比“正常”射电脉冲星的磁场大一个数量级。这两类天体之间潜在的演化联系和差异仍然未知；然而，最近的研究提供了间接证据，将磁星与质量极大的前身恒星联系起来。在此我们报告发现了一个围绕磁星SGR 1900 + 14的红外椭圆环或壳。在前身恒星质量损失或超新星遗迹后续演化的框架内，该环的外观和能量学很难解释。相反，我们认为1998年8月该源发出的巨大耀斑在磁星环境中产生了一个无尘埃的空腔。考虑到耀斑释放的总能量，理论上的尘埃破坏半径与观测到的环的尺寸非常吻合。我们得出结论，SGR 1900 + 14明确与一群大质量恒星相关联，从而巩固了磁星与大质量恒星之间的联系。
