论文标题
用光谱索引图揭示辉空中的隐藏变异性
Revealing Hidden Variability in PWNe With Spectral Index Maps
论文作者
论文摘要
Pulsar风星云（PWNE）是由中子恒星的旋转能膨胀的同步子气泡。观察到它们内部的可变性以前仅限于明显的亮度，或者以固有运动来解释瞬态特征或与PULSAR的可变性相关的少数情况。喷气和圆环的形态也只有在不同的星云的亮度不同的情况下才能看到，并且与我们的视线有利对齐。光谱图分析涉及使用自适应算法进行构造观察，以满足信号极限并根据所需模型参数拟合为结果着色。因此，即使在仅亮度图像并不暗示任何潜在的变化的情况下，光谱指数的微小变化也会显而易见。我们使用档案观测值在任务的20年期间积累了档案观测值，对G21.5-0.9，KES 75，G54.1+0.3，G11.2-0.3和3C 58进行了Chandra X射线研究。借助光谱图分析技术，我们发现了以前未知的变异性的证据，打开了一个新窗口查看应该存的窗口。
Pulsar wind nebulae (PWNe) are the synchrotron bubbles inflated by the rotational energy of a neutron star. Observing variability within them has previously been limited to cases of significant brightening, or the few instances where transient features are interpreted in terms of intrinsic motion or associated with variability from the pulsar. Jet and torus morphology are also only visible in cases of differing brightness with respect to the surrounding nebula and favourable alignment with our line of sight. Spectral map analysis involves binning observations with an adaptive algorithm to meet a signal limit and colouring the results based on the desired model parameter fits. Minute changes in spectral index become therefore apparent even in cases where brightness images alone do not suggest any underlying changes. We present a Chandra X-ray study of the PWNe in G21.5-0.9, Kes 75, G54.1+0.3, G11.2-0.3, and 3C 58, using archival observations accumulated over the ~20-year lifetime of the mission. With the spectral map analysis technique, we discover evidence for previously unknown variability opening a new window into viewing PWNe.
