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arXiv 0712.2843astro-ph
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高能宇宙射线与邻近活动星系核位置的关系

Correlation of the highest-energy cosmic rays with the positions of nearby active galactic nuclei

The Pierre Auger Collaboration

摘要:

皮埃尔俄歇天文台收集的数据提供了具有最高能量的宇宙射线到达方向各向异性的证据,这些宇宙射线与相对较近的活动星系核\cite{science}的位置相关。对于能量大于~ 6x 10 ^{19}$ eV的宇宙射线和距离小于~ 75 Mpc的活动星系核,相关性具有最大意义。我们已经确认了各向异性的置信水平超过99%,通过测试指定的参数{ \em先验},使用一个独立的数据集。观测到的相关性与以下假设是一致的,即具有最高能量的宇宙射线来自足够近的河外源,因此它们的通量不会因与宇宙背景辐射的相互作用而显著衰减(Greisen-Zatsepin-Kuz'min效应)。观测到的相关性的角度尺度是几度,这表明主要是轻的成分,除非我们星系薄盘之外的磁场非常弱。我们目前的资料并不能明确地将活动星系核确定为宇宙射线的来源,而且也不能排除其他分布在活动星系核附近的候选源。我们讨论的前景明确识别的最高能量的宇宙射线的个别来源在几年内继续运作的皮埃尔俄歇天文台。

英文摘要:

Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of the cosmic rays with the highest energies, which are correlated with the positions of relatively nearby active galactic nuclei (AGN) \cite{science}. The correlation has maximum significance for cosmic rays with energy greater than ~ 6x10^{19}$ eV and AGN at a distance less than ~ 75 Mpc. We have confirmed the anisotropy at a confidence level of more than 99% through a test with parameters specified {\em a priori}, using an independent data set. The observed correlation is compatible with the hypothesis that cosmic rays with the highest energies originate from extra-galactic sources close enough so that their flux is not significantly attenuated by interaction with the cosmic background radiation (the Greisen-Zatsepin-Kuz'min effect). The angular scale of the correlation observed is a few degrees, which suggests a predominantly light composition unless the magnetic fields are very weak outside the thin disk of our galaxy. Our present data do not identify AGN as the sources of cosmic rays unambiguously, and other candidate sources which are distributed as nearby AGN are not ruled out. We discuss the prospect of unequivocal identification of individual sources of the highest-energy cosmic rays within a few years of continued operation of the Pierre Auger Observatory.

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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