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arXiv 0811.1160astro-ph
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射电星系黑洞喷流的超高能宇宙射线

Ultra High Energy Cosmic Rays from Black Hole Jets of Radio Galaxies

C. D. Dermer, S. Razzaque, J. D. Finke, A. Atoyan

摘要:

俄歇协作组报告说,大于60 EeV的超高能宇宙射线(UHECR)的到达方向沿超星系面聚集,并在~100 Mpc范围内与活动星系核(AGN)相关。几个事件与附近的射电星系半人马座A的关联支持了这样一种范式,即UHECR由超大质量黑洞发动机提供动力,并在射电星系内部喷流中可变等离子体风形成的冲击中加速到超高能量。75 EeV UHECR质子的GZK视界长度约为100 Mpc,因此俄歇结果与UHECR的假设质子组成一致。在这种情况下,UHECR的来源是FR II射电星系和FR I星系,如Cen A,其散射辐射场增强了UHECR中性束的产生。喷流指向远离我们的射电星系仍然可以被观察到作为UHECR源,这是由于这些星系的射电叶中的磁场使UHECR发生偏转。在blazar活动星系核的光谱中,一个宽带的~1 MeV - 10 EeV辐射分量是由UHECR在河外背景光(EBL)中引起的级联辐射形成的。这种辐射太微弱了,无法从Cen A中看到,但可以从更明亮的耀变体中检测到。

英文摘要:

The Auger Collaboration reports that the arrival directions of >60 EeV ultra-high energy cosmic rays (UHECRs) cluster along the supergalactic plane and correlate with active galactic nuclei (AGN) within ~100 Mpc. The association of several events with the nearby radio galaxy Centaurus A supports the paradigm that UHECRs are powered by supermassive black-hole engines and accelerated to ultra-high energies in the shocks formed by variable plasma winds in the inner jets of radio galaxies. The GZK horizon length of 75 EeV UHECR protons is ~100 Mpc, so that the Auger results are consistent with an assumed proton composition of the UHECRs. In this scenario, the sources of UHECRs are FR II radio galaxies and FR I galaxies like Cen A with scattered radiation fields that enhance UHECR neutral-beam production. Radio galaxies with jets pointed away from us can still be observed as UHECR sources due to deflection of UHECRs by magnetic fields in the radio lobes of these galaxies. A broadband ~1 MeV -- 10 EeV radiation component in the spectra of blazar AGN is formed by UHECR-induced cascade radiation in the extragalactic background light (EBL). This emission is too faint to be seen from Cen A, but could be detected from more luminous blazars.

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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