论文标题
质量四极力矩治疗对快速旋转中子星的射线追踪应用的影响
Effects of the treatment of the mass quadrupole moment on ray-tracing applications for rapidly-rotating neutron stars
论文作者
论文摘要
中子星内部组成探索器（METER）任务通过使用脉冲profile建模技术为限制中子星状态的方程提供了独特的机会。该技术需要准确有效的射线追踪，这反过来又需要在中子恒星周围的时空表示强大的表示。已经提出并使用了几个精确的和近似的指标，并用中等和快速旋转的中子恒星进行射线追踪。在本文中，当用于射线跟踪时，我们进行了几个指标之间的比较。我们使用两个不同的表面公式（来自圆形和新月形热点的热光谱和脉冲曲线）来计算遥远观察者的形状，用于旋转速率的四种旋转速率的四种构型，范围为622至1000 Hz，以及使用一个中等和僵硬的状态和僵硬的状态，包括现实和极端情况。我们发现，从〜700 Hz开始的旋转频率的指标之间的差异很小，理论上可以用于限制四极矩或时空模型。我们还确定在大规模应用中使用每个度量的实用性
The Neutron Star Interior Composition Explorer (NICER) mission has provided a unique opportunity to constrain the equation of state of neutron stars by using the technique of pulse-profile modelling. This technique requires accurate and efficient ray tracing, that in turn requires a robust representation of the spacetime around a neutron star. Several exact and approximate metrics have been proposed, and used, to perform ray tracing around neutron stars, with both moderate and fast rotation. In this paper, we perform a comparison between several of these metrics, when used for ray tracing. We calculate the shape of the neutron star as seen by a distant observer using two different surface formulae, the thermal spectrum and pulse profiles from circular and crescent-shaped hotspots, for four configurations of pulsars with rotation rates ranging from 622 to 1000 Hz, and using both a moderate and a stiff equation of state to include realistic and extreme cases. We find small differences between the metrics for rotation frequencies starting at ~700 Hz that could theoretically be used for constraining the quadrupole moment or the spacetime models. We also determine the practicality of use of each metric in larger-scale applications such as pulse-profile
