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arXiv 2109.07235astro-ph.HEastro-ph.CO
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宇宙gamma-ray传播的人工神经网络

Artificial Neural Networks for cosmic gamma-ray propagation in the Universe

K K Singh, V K Dhar, P J Meintjes

摘要:

我们探讨了潜在的人工神经网络(ANN)为基础的方法智能探测宇宙$γ$ -射线光子在河外宇宙的传播。$γ$ -射线从一个遥远的源,如耀变体发射到地球上的观察者的旅程是通过与河外背景光(EBL)的相互作用的吸收,导致电子-正电子对的生产。这个过程占主导地位的伽马射线光子的能量超过10 GeV的宇宙学距离传播。$γ$射线衰减效应的特征在于一个称为\emph{optical depth}的物理量,它强烈地依赖于$γ$射线光子能量、源的红移和EBL光子的密度。我们估计的光学深度值$γ$射线能量超过10 GeV的红移在0.01至1的范围内使用三种不同的和最有前途的EBL模型从源发出。这些光学深度估计被随机分为两个数据集的人工神经网络的训练和测试使用能量,红移作为输入和光学深度作为输出。每个EBL模型的ANN性能的优化采用标准的反向传播(BP)和径向基函数(RBF)算法。使用RBF神经网络模型的性能被认为是优于BP方法。特别是,与Finke等人(2010)提出的EBL模型相对应的隐藏层中具有40个神经元的RBF-ANN显示了宇宙中$γ$射线传播的最佳性能。

英文摘要:

We explore the potential of an artificial neural network (ANN) based method intelligence to probe the propagation of cosmic $γ$-ray photons in the extragalactic Universe. The journey of $γ$-rays emitted from a distant source like blazar to the observer at the Earth is impeded by the absorption through the interaction with the extragalactic background light (EBL), leading to an electron-positron pair production. This process dominates for gamma ray photons with energy above 10 GeV propagating over the cosmological distances. The effect of $γ$-ray attenuation is characterized by a physical quantity called \emph{optical depth}, which strongly depends on the $γ$-ray photon energy, redshift of the source, and density of the EBL photons. We estimate the optical depth values for $γ$-ray energies above 10 GeV emitted from the sources at redshifts in the range 0.01 to 1 using three different and most promising EBL models. These optical depth estimates are randomly divided into two data sets for training and testing of the ANN using energy, redshift as inputs and optical depth as output. The optimization of ANN-performance for each EBL model employs standard back-propagation (BP) and radial-basis function (RBF) algorithms. The performance of the ANN model using the RBF is found to be superior to the BP method. In particular, the RBF-ANN with 40 neurons in the hidden layer corresponding to the EBL model proposed by Finke et al. (2010) shows the best performance for the propagation of $γ$-rays in the Universe.

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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