arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1701.02488astro-ph.HE
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银河系中心区X射线和gamma-ray辐射的起源

Origin of X-ray and gamma-ray emission from the Galactic central region

D. O. Chernyshov, K. -S. Cheng, V. A. Dogiel, C. M. Ko

摘要:

我们研究了银河系内部几个秒差距的不同非热辐射之间可能存在的联系。本文分析了银河系中心γ射线源2FGL J1745.6-2858(或3FGL J1745.6- 2859 c)的起源和NuSTAR最近发现的弥散硬X射线成分,以及该地区的射电辐射和氢电离过程。我们假设GC中的一个源在过去向周围介质中注入了具有幂律谱的高能粒子,或者直到现在还在继续注入。高能粒子可以是质子、电子或两者的组合。这些粒子扩散到周围介质中,与气体、磁场和背景光子相互作用,产生非热辐射。我们研究了中心源粒子的硬X射线发射和γ射线发射的光谱和空间特征。我们的目标是检查硬X射线和伽马射线发射是否有一个共同的起源。我们的估计表明,在纯强子模型的情况下,硬X射线发射的预期通量太低。尽管质子在γ射线发射中可以产生非零贡献,但是它们和它们的次级电子不太可能在硬X射线通量中做出显著贡献。在纯轻子模型的情况下,有可能再现瞬态和连续供应模型的X射线和伽马射线辐射。然而,在连续供应模型的情况下,分子氢的电离率可能会大大超过观测值。

英文摘要:

We study a possible connection between different non-thermal emissions from the inner few parsecs of the Galaxy. We analyze the origin of the gamma-ray source 2FGL J1745.6-2858 (or 3FGL J1745.6-2859c) in the Galactic Center and the diffuse hard X-ray component recently found by NuSTAR, as well as the radio emission and processes of hydrogen ionization from this area. We assume that a source in the GC injected energetic particles with power-law spectrum into the surrounding medium in the past or continues to inject until now. The energetic particles may be protons, electrons or a combination of both. These particles diffuse to the surrounding medium and interact with gas, magnetic field and background photons to produce non-thermal emissions. We study the spectral and spatial features of the hard X-ray emission and gamma-ray emission by the particles from the central source. Our goal is to examine whether the hard X-ray and gamma-ray emissions have a common origin. Our estimations show that in the case of pure hadronic models the expected flux of hard X-ray emission is too low. Despite protons can produce a non-zero contribution in gamma-ray emission, it is unlikely that they and their secondary electrons can make a significant contribution in hard X-ray flux. In the case of pure leptonic models it is possible to reproduce both X-ray and gamma-ray emissions for both transient and continuous supply models. However, in the case of continuous supply model the ionization rate of molecular hydrogen may significantly exceed the observed value.

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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