发表机构
University of Maryland, Baltimore County; NASA Goddard Space Flight Center（马里兰大学巴尔的摩分校; 美国宇航局戈达德太空飞行中心）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出半人马座A附近UHECR过量可能源于过去GRB 221009A类事件，模拟本地群体，估计天空存在3-7个过量，并可通过奥格天文台和望远镜阵列数据检验。
AI 中文摘要
超高能宇宙射线（UHECR）天空中最为显著的特征是来自半人马座A（Cen A）附近区域的事件存在显著过量。本文研究该过量是否可能由过去的GRB 221009A类事件而非Cen A本身所导致。如果一场非凡的伽马射线暴（GRB）在Cen A/M83星系群内的某个矮星系中爆发，星系际磁场偏转将自然地扩散并延迟其宇宙射线信号，使其在约$2\times 10^{5}$年内可见。将此放大，我们在Greisen--Zatsepin--Kuzmin（GZK）视界内模拟了这类异常明亮、窄喷流的暂现源的本地群体。对于本地体积率$\dot n_0\simeq4\times10^{-8}\\ {\rm Mpc^{-3}\\,yr^{-1}}$和喷流半开角$0.8^\circ$，我们估计在任意给定时间天空中存在约3-7个UHECR过量。改变喷流开角、GZK体积和可见时间会导致过量值范围更广。通过将群体预测与皮埃尔·奥格天文台和望远镜阵列获得及即将获得的UHECR各向异性数据进行比较，可以检验这一假设。
英文摘要
The most prominent feature in the ultra-high-energy cosmic ray (UHECR) sky is a significant excess of events from the vicinity of Centaurus A (Cen A). In this paper we investigate whether the excess may be caused by a past GRB 221009A-like event rather than Cen A itself. If an extraordinary gamma-ray burst (GRB) went off in one of the dwarf galaxies within the Cen A/M83 group, intergalactic magnetic deflections would naturally spread out and delay its cosmic ray signal, making it visible for $\sim 2\times 10^{5}$ years. Scaling this up, we model a local population of these exceptionally bright, narrow-jet transients within the \text{Greisen--Zatsepin--Kuzmin} (GZK) horizon. For a local volumetric rate of $\dot n_0\simeq4\times10^{-8}\ {\rm Mpc^{-3}\,yr^{-1}}$ and a jet half-opening angle of $0.8^\circ$, we estimate $\simeq3-7$ UHECR excesses across the sky at any given time. Varying the jet opening angle, GZK volume, and visibility time results in a broader range of excess values. It is possible to test this hypothesis by comparing the population predictions against existing and upcoming UHECR anisotropy data obtained by the Pierre Auger Observatory and the Telescope Array.
Comments5 pages, 1 figure
