English

Electron and positron spectra in the three dimensional spatial-dependent propagation model

High Energy Astrophysical Phenomena 2020-08-26 v1

Abstract

The spatial-dependent propagation model has been successfully used to explain diverse observational phenomena, including the spectral hardening of cosmic-ray nuclei above 200200 GV, the large-scale dipole anisotropy and the diffusive gamma distribution. In this work, we further apply the spatial-dependent propagation model to both electrons and positrons. To account for the excess of positrons above 1010 GeV, an additional local source is introduced. And we also consider a more realistic spiral distribution of background sources. We find that due to the gradual hardening above 1010 GeV, the hardening of electron spectrum above tens of GeV can be explained in the SDP model and both positron and electron spectra less than TeV energies could be naturally described. The spatial-dependent propagation with spiral-distributed sources could conforms with the total electron spectrum in the whole energy. Meanwhile compared with the conventional model, the spatial-dependent propagation with spiral-distributed sources could produce larger background positron flux, so that the multiplier of background positron flux is 1.421.42, which is much smaller than the required value by the conventional model. Thus the shortage of background positron flux could be solved. Furthermore we compute the anisotropy of electron under spatial-dependent propagation model, which is well below the observational limit of Fermi-LAT experiment.

Keywords

Cite

@article{arxiv.1904.10663,
  title  = {Electron and positron spectra in the three dimensional spatial-dependent propagation model},
  author = {Zhen Tian and Wei Liu and Bo Yang and Xue-Dong Fu and Hai-Bo Xu and Yu-hua Yao and Yi-Qing Guo},
  journal= {arXiv preprint arXiv:1904.10663},
  year   = {2020}
}
R2 v1 2026-06-23T08:48:01.346Z