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arXiv 1111.4216astro-ph.HE
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银河系中心脉冲星星族的多波长约束

Multiwavelength Constraints on Pulsar Populations in the Galactic Center

R. S. Wharton, S. Chatterjee, J. M. Cordes, J. S. Deneva, T. J. W. Lazio

摘要:

在银河系中心几个秒差距内探测射电望远镜,将为银河系中心(GC)的引力和磁离子环境提供一个独特的探测器,如果足够接近Sgr A*,还可以在强场区精确检验广义相对论。虽然由于星际散射,很难在无线电波长上找到双星,但从GC中双星的详细时间获得的回报值得共同努力。为了激励脉冲星调查,并帮助他们定义搜索参数,我们约束脉冲星的数量和空间分布使用广泛的多波长测量。其中包括在Sgr A* 15弧分范围内的五个已知射电天体,漫射发射的射电和伽马射线测量,中央秒差距高频脉冲星巡天中的未探测,来自成像巡天的射电点源目录,中央几秒差距大质量恒星群的红外观测,候选脉冲星风星云在内部20秒差距和估计的核心崩溃超新星率的基础上的X射线测量。我们发现,在目前的观测限制下,银河系内部的秒差距可能有多达10^3个活跃的射电望远镜射向地球。如此大的群体将使Sgr A* 的本征光谱和沿着Sgr A* 的视线的自由-自由吸收的低频测量失真。

英文摘要:

The detection of radio pulsars within the central few parsecs of the Galaxy would provide a unique probe of the gravitational and magneto-ionic environments in the Galactic Center (GC) and, if close enough to Sgr A*, precise tests of general relativity in the strong-field regime. While it is difficult to find pulsars at radio wavelengths because of interstellar scattering, the payoff from detailed timing of pulsars in the GC warrants a concerted effort. To motivate pulsar surveys and help define search parameters for them, we constrain the pulsar number and spatial distribution using a wide range of multiwavelength measurements. These include the five known radio pulsars within 15 arcmin of Sgr A*, radio and gamma-ray measurements of diffuse emission, non-detections in high frequency pulsar surveys of the central parsec, a catalog of radio point sources from an imaging survey, infrared observations of massive star populations in the central few parsecs, candidate pulsar wind nebulae in the inner 20 pc and estimates of the core-collapse supernova rate based on X-ray measurements. We find that under current observational constraints, the inner parsec of the Galaxy could harbor as many as ~10^3 active radio pulsars that are beamed towards Earth. Such a large population would distort the low-frequency measurements of both the intrinsic spectrum of Sgr A* and the free-free absorption along the line of sight of Sgr A*.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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