SPATIAL-DEPENDENT PROPAGATION OF COSMIC RAYS RESULTS IN SPECTRUM OF PROTON, RATIOS OF , B/C AND ANISOTROPY OF NUCLEI.

Autor: Yi-Qing Guo, Zhen Tian, Chao Jin
Předmět:
Zdroj: Astrophysical Journal; 3/1/2016, Vol. 819 Issue 1, p1-1, 1p
Abstrakt: Recent precise measurements of cosmic ray spectra revealed an anomalous hardening at ∼200 GV, observed by the ATIC, CREAM, PAMELA, and AMS02 experiments. Particularly, the latest observation of the ratio by AMS02 demonstrated a flat distribution, which further validated the spectral anomalies of secondary particles. All those new phenomena indicated that the conventional propagation model of cosmic rays meets a challenge. In this work, the spatial-dependent diffusion coefficient is employed by tracing the source distribution under the physical picture of the two-halo model in the DRAGON package. Under such a scenario, the model calculation will result in two-component spectra for primary nuclei. Due to the smaller rigidity dependence of in the galactic disk, the ratios secondary-to-primary will inevitably be flatter and the expected anisotropy of cosmic rays will be much more attenuated than in the conventional model. As a result, we can reproduce the spectral hardening of protons, the flat ratios of and B/C, and consistent anisotropy from ∼100 GeV to ∼100 TeV by only adopting one set of spatial-dependent diffusion coefficients in a galactic disk. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index