Implications on the origin of cosmic rays in light of 10 TV spectral softenings

Chuan Yue; Peng-Xiong Ma; Qiang Yuan; Yi-Zhong Fan; Zhan-Fang Chen; Ming-Yang Cui; Hao-Ting Dai; Tie-Kuang Dong; Xiaoyuan Huang; Wei Jiang; Shi-Jun Lei; Xiang Li; Cheng-Ming Liu; Hao Liu; Yang Liu; Chuan-Ning Luo; Xu Pan; Wen-Xi Peng; Rui Qiao; Yi-Feng Wei; Li-Bo Wu; Zhi-Hui Xu; Zun-Lei Xu; Guan-Wen Yuan; Jing-Jing Zang; Ya-Peng Zhang; Yong-Jie Zhang; Yun-Long Zhang

doi:10.1007/s11467-019-0946-8

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arXiv · 1909.12857

Implications on the origin of cosmic rays in light of 10 TV spectral softenings

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Abstract

Precise measurements of the energy spectra of cosmic rays (CRs) show various kinds of features deviating from single power-laws, which give very interesting and important implications on their origin and propagation. Previous measurements from a few balloon and space experiments indicate the existence of spectral softenings around 10 TV for protons (and probably also for Helium nuclei). Very recently, the DArk Matter Particle Explorer (DAMPE) measurement about the proton spectrum clearly reveals such a softening with a high significance. Here we study the implications of these new measurements, as well as the groundbased indirect measurements, on the origin of CRs. We find that a single component of CRs fails to fit the spectral softening and the air shower experiment data simultaneously. In the framework of multiple components, we discuss two possible scenarios, the multiple source population scenario and the background plus nearby source scenario. Both scenarios give reasonable fits to the wide-band data from TeV to 100 PeV energies. Considering the anisotropy observations, the nearby source model is favored.

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Chuan Yue, Peng-Xiong Ma, Qiang Yuan, Yi-Zhong Fan, Zhan-Fang Chen, Ming-Yang Cui, Hao-Ting Dai, Tie-Kuang Dong, Xiaoyuan Huang, Wei Jiang, Shi-Jun Lei, Xiang Li, Cheng-Ming Liu, Hao Liu, Yang Liu, Chuan-Ning Luo, Xu Pan, Wen-Xi Peng, Rui Qiao, Yi-Feng Wei, Li-Bo Wu, Zhi-Hui Xu, Zun-Lei Xu, Guan-Wen Yuan, Jing-Jing Zang, Ya-Peng Zhang, Yong-Jie Zhang, Yun-Long Zhang. 2019-09-27. Implications on the origin of cosmic rays in light of 10 TV spectral softenings. https://doi.org/10.1007/s11467-019-0946-8

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