Search for Anisotropy of Ultrahigh Energy Cosmic Rays with the Telescope Array Experiment
Search for Anisotropy of Ultrahigh Energy Cosmic Rays with the Telescope Array Experiment
复制标题
用望远镜阵列实验寻找超高能宇宙线的各向异性
DOI：
10.1088/0004-637x/757/1/26
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
et al.
中科院分区：
文献类型：
--
作者：
T. Abu-Zayyad;T.Fujii(l39人中7番目);et al.
我们研究了望远镜阵列（TA）探测器在运行的前40个月收集的超高能宇宙线（UHECR）事件的各向异性。根据早期的研究，我们研究了能量阈值为10 EeV，40 EeV和57 EeV的事件集。我们发现，赤Ascension和赤纬事件的分布在所有三组中都与各向同性分布兼容。然后，我们与以前报道的UHECR事件在小角度尺度的集群进行比较。在TA数据中没有发现显著的聚类。然后，我们检查事件与E> 57 EeV的相关性与附近的活动星系核。最后，我们检查了所有三组与宇宙大尺度结构（LSS）的相关性。我们发现，这两个较高的能量集是兼容的各向同性分布和假设，UHECR源遵循宇宙的物质分布（LSS假设），而事件集与E> 10 EeV是兼容的各向同性和不兼容的LSS假设在95%CL，除非大的偏转角也假设。我们表明，占UHECR偏转在一个现实的银河系磁场模型可以使这一套兼容的LSS假设。
We study the anisotropy of Ultra-High Energy Cosmic Ray (UHECR) events collected by the Telescope Array (TA) detector in the first 40 months of operation. Following earlier studies, we examine event sets with energy thresholds of 10 EeV, 40 EeV, and 57 EeV. We find that the distributions of the events in right ascension and declination are compatible with an isotropic distribution in all three sets. We then compare with previously reported clustering of the UHECR events at small angular scales. No significant clustering is found in the TA data. We then check the events with E> 57 EeV for correlations with nearby active galactic nuclei. No significant correlation is found. Finally, we examine all three sets for correlations with the large-scale structure (LSS) of the universe. We find that the two higher-energy sets are compatible with both an isotropic distribution and the hypothesis that UHECR sources follow the matter distribution of the universe (the LSS hypothesis), while the event set with E> 10 EeV is compatible with isotropy and is not compatible with the LSS hypothesis at 95% CL unless large deflection angles are also assumed. We show that accounting for UHECR deflections in a realistic model of the Galactic magnetic field can make this set compatible with the LSS hypothesis.