发表机构
Institute of High Energy Physics, Chinese Academy of Sciences; School of Physical Sciences, University of Chinese Academy of Sciences; Institute of Theoretical Physics, Faculty of Physics, University of Warsaw（中国科学院高能物理研究所; 中国科学院大学物理科学学院; 华沙大学物理学院理论物理研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文模拟低质量磁单极子在银河系中的传播，发现其到达方向呈各向异性，并与皮埃尔·奥格数据比较，在多数情况下无磁单极子贡献更受青睐，并设定了90%置信水平下的通量上限。
AI 中文摘要
超高能宇宙线的起源和组成仍不确定，尤其是那些超过格雷森-扎采平-库兹明截断且表观到达方向指向本地空洞的罕见事件。本文深入研究了这些宇宙线可能包含几种近期理论模型所预言的低质量磁单极子的可能性。通过使用CRPropa（一种用于模拟宇宙线传播的最新代码）的自定义扩展，在质量、磁荷和初始相空间分布的现实假设下，对磁单极子在银河环境中的传播进行了追踪。我们的模拟表明，遗迹磁单极子沿着丝状的“银河磁漏斗”运动，在地球上产生各向异性的到达方向。预期的到达方向集中在天空的一个小区域内，这对未来搜索的设计和解释具有重要意义。将模拟的到达方向与皮埃尔·奥格天文台的数据集进行比较表明，在大多数情况下，零假设（即无磁单极子贡献）在统计上更受青睐。通过结合方向和能量信息的轮廓似然分析，我们设定了积分磁单极子通量在90%置信水平的上限为$< 2.1\times10^{-23}$ $\mathrm{cm^{-2}s^{-1}sr^{-1}}$。
英文摘要
Origin and composition of ultra-high energy cosmic rays are still uncertain, particularly the rare events exceeding the Greisen-Zatsepin-Kuzmin cutoff and whose apparent arrival directions point to the Local Void. This work is an in-depth investigation of the possibility that such cosmic rays contain low-mass magnetic monopoles predicted in several recent theoretical models. Using a custom extension to CRPropa, a state-of-the-art code for modeling cosmic ray propagation, monopoles are tracked in the galactic environment under realistic assumptions on mass, magnetic charge, and initial phase-space distributions. Our simulations demonstrate that relic MMs follow filamentary ``Galactic magnetic funnels'', producing anisotropic arrival directions at Earth. The expected arrival directions are concentrated in a small region of the sky, which has significant implications for the design and interpretation of future searches. A comparison of the simulated arrival directions with the Pierre Auger Observatory dataset shows that the null hypothesis - no monopole contribution - is statistically preferred for the majority of cases. Using a profile-likelihood analysis that incorporates both directional and energy information, we set 90% C.L. upper limits on the integral MM flux of $< 2.1\times10^{-23}$ $\mathrm{cm^{-2}s^{-1}sr^{-1}}$.
Comments32 pages, 19 figures
