论文标题
钱德拉（Chandra）的X射线研究证实，磁标准AP星KQ VEL拥有中子星伴侣
Chandra's X-ray study confirms that the magnetic standard Ap star KQ Vel hosts a neutron star companion
论文作者
论文摘要
KQ Vel是一个奇特的A0P恒星，其强大的表面磁场约为7.5 kg。它的旋转时间较慢，为近8年。 Bailey等。 （2015年）检测到了不确定性质的二元伴侣，并建议它可能是中子之星或黑洞。在这封信中，我们分析了Chandra望远镜获得的X射线数据，以确定有关恒星及其伴侣之间恒星磁场和相互作用的信息。我们以相对较大的X射线光度为2 \ times 10^{30} erg/s确认对KQ Vel的先前X射线检测。 X射线光谱表明在> 20MK，可能是非热成分的热气体。 X射线光曲线是可变的，但是需要更好的质量数据以确定如果有的话。我们将X射线光谱解释为两个组成部分的组合：非热发射由A0P恒星上的Aurora产生，而热的血浆填充了围绕“推动”中子恒星的延伸壳。我们探索了各种替代方案，但是涉及恒星磁层的混合模型以及在推动中子恒星周围的热外壳似乎最合理。我们推测KQ Vel最初是一个三重系统，AP星是合并产品。我们得出的结论是，KQ Vel是一种由强磁主序列和中子星组成的中间质量二元。
KQ Vel is a peculiar A0p star with a strong surface magnetic field of about 7.5 kG. It has a slow rotational period of nearly 8 years. Bailey et al. (2015) detected a binary companion of uncertain nature, and suggested it could be a neutron star or a black hole. In this Letter we analyze X-ray data obtained by the Chandra telescope to ascertain information about the stellar magnetic field and interaction between the star and its companion. We confirm previous X-ray detection of KQ Vel with a relatively large X-ray luminosity of 2\times 10^{30} erg/s. X-ray spectra suggest the presence of hot gas at > 20MK and, possibly, of a non-thermal component. X-ray light curves are variable, but better quality data are needed to determine periodicity if any. We interpret X-ray spectra as a combination of two components: the non-thermal emission arising from the aurora on the A0p star and the hot thermal plasma filling the extended shell surrounding the "propelling" neutron star. We explore various alternatives, but a hybrid model involving the stellar magnetosphere along with a hot shell around the propelling neutron star seems most plausible. We speculate that KQ Vel was originally a triple system, and the Ap star is a merger product. We conclude that KQ Vel is an intermediate-mass binary consisting of a strongly magnetic main sequence star and a neutron star.
