Interpretations of the DAMPE electron data

作者：Qiang Yuan, Lei Feng, Peng‐Fei Yin, Yi-Zhong Fan, Xiao-Jun Bi, Maxwell Cui, Tiekuang Dong, Yi-Qing Guo, Kun Fang, Hongbo Hu, Xiaoyuan Huang, Shijun Lei, Xiang Li, Sujie Lin, Hao Liu, Peng-Xiong Ma, Wen-Xi Peng, Rui Qiao, Zhao-Qiang Shen, Meng Su, Yifeng Wei, Z. R. Xu, Chuan Yue, Jing-Jing Zang, Cun Zhang, Xinmin Zhang, Yapeng Zhang, Yongjie Zhang, Yun‐Long Zhang · 发表于：arXiv (Cornell University) · 年份：2017 · DOI：10.48550/arxiv.1711.10989 · 被引用次数：44 · 研究领域：Dark Matter and Cosmic Phenomena、Cosmology and Gravitation Theories、Particle physics theoretical and experimental studies

The DArk Matter Particle Explorer (DAMPE), a high energy cosmic ray and $γ$-ray detector in space, has recently reported the new measurement of the total electron plus positron flux between 25 GeV and 4.6 TeV. A spectral softening at $\sim0.9$ TeV and a tentative peak at $\sim1.4$ TeV have been reported. We study the physical implications of the DAMPE data in this work. The presence of the spectral break significantly tightens the constraints on the model parameters to explain the electron/positron excesses. The spectral softening can either be explained by the maximum acceleration limits of electrons by astrophysical sources, or a breakdown of the common assumption of continuous distribution of electron sources at TeV energies in space and time. The tentive peak at $\sim1.4$ TeV implies local sources of electrons/positrons with quasi-monochromatic injection spectrum. We find that the cold, ultra-relativistic $e^+e^-$ winds from pulsars may give rise to such a structure. The pulsar is requird to be middle-aged, relatively slowly-rotated, mildly magnetized, and isolated in a density cavity. The annihilation of DM particles ($m_χ\sim1.5$ TeV) into $e^+e^-$ pairs in a nearby clump or an over-density region may also explain the data. In the DM scenario, the inferred clump mass (or density enhancement) is about $10^7-10^8$ M$_\odot$ (or $17-35$ times of the canonical local density) assuming a thermal production cross section, which is relatively extreme compared with the expectati...