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arXiv 1702.03211astro-ph.HE
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银河系外背景光的空间涨落对硬Gamma Ray谱的影响

Effects of Spatial Fluctuations in the Extra Galactic Background Light on Hard Gamma Ray Spectra

A. M. Kudoda, A. Faltenbacher

摘要:

本文研究了银河系外背景光(EBL)的涨落对遥远耀变体硬$γ$射线谱衰减的影响。EBL的波动发生在100 Mpc的尺度上,是由星系团造成的。EBL光子通过电子-正电子对产生机制:$γ+ γ' \rightarrow e^+ + e^-$与高能$γ$ -射线相互作用。$γ$ -射线的衰减取决于它们的能量和介入EBL光子场的密度。使用一个简单的模型的平均EBL光子密度的演变,我们实现了EBL波动的分析描述。我们发现EBL能量密度的振幅可以随环境的变化而变化$\pm 1\%$。EBL的波动导致光学深度的轻微变化,或相当于来自遥远耀变体的$γ$射线的transmittance。我们的模型预测了$\pm 10\%$在$γ$射线透射中的最大变化。然而,这转化为目前观察到的$γ$射线光谱的幂律斜率的边际差异。如果包括EBL涨落,去吸收的$γ$射线谱的斜率相差不超过$\pm 1\%$.

英文摘要:

This study investigates the impact of the fluctuations in the extra galactic background light (EBL) on the attenuation of the hard $γ$-ray spectra of distant blazars. EBL fluctuations occur on the scales up to 100 Mpc and are caused by clustering of galaxies. The EBL photons interact with high energy $γ$-rays via the electron-positron pair production mechanism: $γ+ γ' \rightarrow e^+ + e^-$. The attenuation of $γ$-rays depends on their energy and the density of the intervening EBL photon field. Using a simple model for the evolution of the mean EBL photon density, we implement an analytical description of the EBL fluctuations. We find that the amplitudes of the EBL energy density can vary by $\pm 1\%$ as a function of environment. The EBL fluctuations lead to mild alterations of the optical depth or equivalently the transmissivity for $γ$-rays from distant blazars. Our model predicts maximum changes of $\pm 10\%$ in the $γ$-ray transmissivity. However, this translates into marginal differences in the power law slopes of currently observed $γ$-ray spectra. The slopes of deabsorbed $γ$-ray spectra differ by not more than $\pm 1\%$ if EBL fluctuations are included.

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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