arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1108.4822astro-ph.HE
收藏

星际cosmic-ray电子能谱的同步辐射和直接测量

The interstellar cosmic-ray electron spectrum from synchrotron radiation and direct measurements

A. W. Strong, E. Orlando, T. R. Jaffe

摘要:

背景:银河宇宙射线电子、磁场和同步辐射之间的关系。目的:我们利用同步辐射来限制低能星际电子谱,使用各种无线电调查和连接从费米-LAT和其他实验的电子数据。方法:采用GALPROP宇宙线传播、γ射线和同步辐射程序。包括次级电子和正电子。宇宙射线和伽马射线数据的基础上的传播模型进行了测试对同步辐射数据从22 MHz到94 GHz。结果:同步加速器数据证实了宇宙射线电子注入谱需要一个低能量的突破。低于几个GeV的星际光谱必须低于标准模型的预测,这表明太阳调制比通常假设的要少。再加速模型更难与同步加速器约束相协调。我们表明,次级轻子是重要的同步辐射的解释。我们还考虑了宇宙线传播起源的低能量突破。结论:利用宇宙射线和同步加速器上的互补信息,对电子给出了独特而重要的约束,并对伽马射线产生了影响。鉴于普朗克和费米的任务正在进行,这种联系现在尤其重要。

英文摘要:

Context: The relation between Galactic cosmic-ray electrons, magnetic fields and synchrotron radiation. Aims: We exploit synchrotron radiation to constrain the low-energy interstellar electron spectrum, using various radio surveys and connecting with electron data from Fermi-LAT and other experiments. Methods: The GALPROP programme for cosmic-ray propagation, gamma-ray and synchrotron radiation is used. Secondary electrons and positrons are included. Propagation models based on cosmic-ray and gamma-ray data are tested against synchrotron data from 22 MHz to 94 GHz. Results: The synchrotron data confirm the need for a low-energy break in the cosmic-ray electron injection spectrum. The interstellar spectrum below a few GeV has to be lower than standard models predict, and this suggests less solar modulation than usually assumed. Reacceleration models are more difficult to reconcile with the synchrotron constraints. We show that secondary leptons are important for the interpretation of synchrotron emission. We also consider a cosmic-ray propagation origin for the low-energy break. Conclusions: Exploiting the complementary information on cosmic rays and synchrotron gives unique and essential constraints on electrons, and has implications for gamma rays. This connection is especially relevant now in view of the ongoing PLANCK and Fermi missions.

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。

↑