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arXiv 0809.3057astro-phhep-ph
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关于超高能宇宙射线的加速

On the acceleration of Ultra-High-Energy Cosmic Rays

Federico Fraschetti

摘要:

超高能宇宙射线(UHECR)以超过$10^{18}$ eV的能量撞击地球大气层。这与以100 km/h速度运动的网球所携带的能量相同,但集中在亚原子粒子上。UHECR非常罕见(具有$E > 10^{20}$ eV的粒子通量为0.5/km $^2$ /世纪),因此在过去50年中仅检测到少数此类粒子。最近,HiRes和Auger实验报告了在UHECR光谱中发现了高能截止,Auger发现了最高能量事件向附近活动星系核的明显聚集。共识是,最高能量的粒子在这些物体的射电亮叶内加速,但目前尚不清楚这实际上是如何发生的,以及截止是由于传播效应还是反映了加速过程的内在物理限制。目前,低事件统计允许许多不同的合理模型;然而,观测开始对它们施加强有力的限制。这些观察也激发了新物理学可能涉及的建议。我们提出了一个审查的关键理论和观测问题的传播和加速过程中的UHECR和提出的解决方案。

英文摘要:

Ultra High Energy Cosmic Rays (UHECRs) hit the Earth's atmosphere with energies exceeding $10^{18}$ eV. This is the same energy as carried by a tennis ball moving at 100 km/h, but concentrated on a sub-atomic particle. UHECRs are so rare (the flux of particles with $E > 10^{20}$ eV is 0.5/km$^2$/century) that only a few such particles have been detected over the past 50 years. Recently, the HiRes and Auger experiments have reported the discovery of a high-energy cut-off in the UHECR spectrum, and Auger has found an apparent clustering of the highest energy events towards nearby active galactic nuclei. Consensus is building that the highest energy particles are accelerated within the radio-bright lobes of these objects, but it remains unclear how this actually happens, and whether the cut-off is due to propagation effects or reflects an intrinsically physical limitation of the acceleration process. The low event statistics presently allows for many different plausible models; nevertheless observations are beginning to impose strong constraints on them. These observations have also motivated suggestions that new physics may be implicated. We present a review of the key theoretical and observational issues related to the processes of propagation and acceleration of UHECRs and proposed solutions.

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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