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arXiv 1102.3123astro-ph.HE
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超新星残余激波中的Cosmic Ray谱

Cosmic Ray Spectrum in Supernova Remnant Shocks

Hyesung Kang

摘要:

我们进行了动力学模拟扩散冲击加速Ia型超新星遗迹(SNRs)扩展到一个统一的星际介质(ISM)。震前气体温度是决定宇宙线加速的主要参数,而磁场强度和宇宙线注入率是次要参数。热ISM中的SNR(具有小于10^{-4}的注入分数)是低效的加速器,其中小于10%的能量转化为CR。激波结构几乎是试验粒子状的,随后的CR谱可能比E^{-2}更陡。虽然在前体中使用放大的磁场可以将粒子加速到10^{15.5}Z eV的膝能,但是散射中心的阿尔芬漂移使源谱变软,如E^{-2.1}那样陡峭,并且降低CR加速效率。

英文摘要:

We performed kinetic simulations of diffusive shock acceleration in Type Ia supernova remnants (SNRs) expanding into a uniform interstellar medium (ISM). The preshock gas temperature is the primary parameter that governs the cosmic ray (CR) acceleration, while magnetic field strength and CR injection rate are secondary parameters. SNRs in the hot ISM, with an injection fraction smaller than 10^{-4}, are inefficient accelerators with less than 10 % energy getting converted to CRs. The shock structure is almost test-particle like and the ensuing CR spectrum can be steeper than E^{-2}. Although the particles can be accelerated to the knee energy of 10^{15.5}Z eV with amplified magnetic fields in the precursor, Alfv'enic drift of scattering centers softens the source spectrum as steep as E^{-2.1} and reduces the CR acceleration efficiency.

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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