Axion-like particles (ALPs), predicted in theories beyond the Standard Model, can have observational effects on the transparency of the Universe to $\gamma$ rays in the presence of magnetic fields. In this work, we search for effects compatible with the existence of ALPs with 80 months of data from the ${\it Fermi}$ Large Area Telescope, by comparing the distributions of observed highest energy photons from sources beyond redshifts of z $\geq$ 0.1 with theoretical predictions in the presence of ALPs. We find no evidence for an increased $\gamma$-ray transparency due to ALPs and therefore we set limits on the ALPs parameters assuming a value of the intergalactic magnetic field strength of 1 nG. Photon-ALP couplings above $10^{-11}$ GeV$^{-1}$ are excluded for ALP masses $m_{a}$ $\lesssim3.0$ neV. These limits exclude a region of the parameter space not covered by other $\gamma$-ray telescopes and are compatible with constraints imposed by other experiments.

中文翻译：

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在硬γ射线耀变体的最高能量光子中寻找轴子状粒子的印记

在超出标准模型的理论中预测的类轴子粒子 (ALP) 可以对宇宙在磁场存在下对 $\gamma$ 射线的透明度产生观测影响。在这项工作中，我们通过比较来自 z $\geq 红移以外的来源的观测到的最高能量光子的分布，寻找与 ALP 存在兼容的效应，这些效应来自 ${\it Fermi}$ 大面积望远镜的 80 个月数据在存在 ALP 的情况下，理论预测为 0.1 美元。我们没有发现 ALPs 导致 $\gamma$ 射线透明度增加的证据，因此我们对 ALPs 参数设置了限制，假设星系间磁场强度值为 1 nG。高于 $10^{-11}$ GeV$^{-1}$ 的光子-ALP 耦合被排除在 ALP 质量 $m_{a}$ $\lesssim3.0$ neV 之外。