论文标题
比较银河凸出和银河盘毫秒脉冲星
Comparing the Galactic Bulge and Galactic Disk Millisecond Pulsars
论文作者
论文摘要
银河中心过量（GCE）是在费米大面积望远镜（Fermi-LAT）数据中发现的星系中心区域的扩展伽马射线源。 GCE的主要解释之一是银河凸起中未解决的毫秒脉冲星（MSP）的人群。由于恒星形成历史的不同，预计银河系中的MSP比银河系磁盘中的MSP更老，因此变暗。另外，已经观察到MSP的光谱参数与相应中子星的旋转速率之间的相关性。这意味着凸起的MSP可能与磁盘MSP频谱不同。我们对MSP进行详细的建模，从形成到观察。尽管我们确认了相关性，但我们发现它们不足以显着区分凸起的MSP和磁盘MSP的光谱，当时不确定性。我们的结果表明，可以解释来自银河磁盘中已解析的MSP的伽马射线信号的MSP人群以及方形凸起和核凸起中未解决的MSP的群体可以被描述为源于与所有这些不同环境共有的天体物质来源的某些子集的共同进化轨迹引起的。我们不要求内部星系MSP有任何异常来解释GCE。此外，我们使用更准确的几何形状进行凸出MSP的分布，并结合了MSPS距离的分散度量估计值。我们发现，伸长的凸出凸起形态意味着一些凸起的MSP更靠近我们，因此更容易解决。我们确定了三个已解决的MSP，这些MSP具有很大的属于凸起人群的概率。
The Galactic Center Excess (GCE) is an extended gamma-ray source in the central region of the Galaxy found in Fermi Large Area Telescope (Fermi-LAT) data. One of the leading explanations for the GCE is an unresolved population of millisecond pulsars (MSPs) in the Galactic bulge. Due to differing star formation histories it is expected that the MSPs in the Galactic bulge are older and therefore dimmer than those in the Galactic disk. Additionally, correlations between the spectral parameters of the MSPs and the spin-down rate of the corresponding neutron stars have been observed. This implies that the bulge MSPs may be spectrally different from the disk MSPs. We perform detailed modelling of the MSPs from formation until observation. Although we confirm the correlations, we do not find they are sufficiently large to significantly differentiate the spectra of the bulge MSPs and disk MSPs when the uncertainties are accounted for. Our results demonstrate that the population of MSPs that can explain the gamma-ray signal from the resolved MSPs in the Galactic disk and the unresolved MSPs in the boxy bulge and nuclear bulge can consistently be described as arising from a common evolutionary trajectory for some subset of astrophysical sources common to all these different environments. We do not require that there is anything unusual about inner Galaxy MSPs to explain the GCE. Additionally, we use a more accurate geometry for the distribution of bulge MSPs and incorporate dispersion measure estimates of the MSPs' distances. We find that the elongated boxy bulge morphology means that some the bulge MSPs are closer to us and so easier to resolve. We identify three resolved MSPs that have significant probabilities of belonging to the bulge population.
