论文标题
银河宇宙射线种群的巨大恒星簇起源于非常高的能量
Massive star cluster origin for the galactic cosmic ray population at very-high energies
论文作者
论文摘要
我们证明，嵌入巨大的星形簇中的超新星残留（SNR）冲击可以再现在地球附近测得的宇宙射线质子和全粒子光谱，高达数百个PETA-Electronvolts（PEV）。我们对两类巨大的星团群进行建模。第一批人口是“松散的集群”，不能为集体风终止冲击供电。然后，SNR冲击以低密度和弱磁性介质扩展，该种群主要促成1 PEV左右的CR光谱的“膝盖”。第二个人口是年轻的紧凑型群集，它们的功能强大且紧凑，足以维持集体的风流。然后，SNR冲击从簇膨胀到强烈磁性的风，并加速核直至超高的能量。然而，该人群仅占所有银河大型恒星簇的15％，但仍占据了〜1至100 PEV之间的频谱。虽然仅这两个组件就可以重现高达数百个PEV的CR谱的形状，从而增加了由组成和各向异性测量值动机的光层外层次分量，可以将光谱重现至最高能量。拟合参数系统地链接到值的物理变量，其值与理论期望一致。
We demonstrate that supernova remnant (SNR) shocks embedded within massive star clusters can reproduce both the cosmic-ray proton and all-particle spectra measured in the vicinity of the Earth up to hundreds of peta-electronvolts (PeV). We model two classes of massive star clusters. The first population are "loose clusters" which do not power a collective wind termination shock. SNR shocks then expand in a low-density and weakly magnetised medium, and this population mainly contributes up to the "knee" of the CR spectrum around 1 PeV. The second population are young compact clusters, which are powerful and compact enough to sustain a collective wind outflow. SNR shocks then expand from the cluster into the strongly magnetised wind and accelerate nuclei up to ultra-high energies. This population, representing only about 15% of all Galactic massive star clusters, nevertheless dominates the spectrum between ~ 1 and 100 PeV. While these two components alone can reproduce the shape of the CR spectrum up to hundreds of PeV, adding a light sub-ankle extragalactic component motivated by composition and anisotropy measurements, allows to reproduce the spectrum up to the highest energies. Fitting parameters are systematically linked to physical variables whose values are in line with theoretical expectations.
