论文标题
检测宇宙射线硼至碳与碳与氧气通量比的光谱硬质与潮湿的比率
Detection of spectral hardenings in cosmic-ray boron-to-carbon and boron-to-oxygen flux ratios with DAMPE
论文作者
论文摘要
据信，宇宙射线（CR）中的硼核主要是通过与星际物质碰撞的较重核（例如碳和氧气）的碎片产生的。因此，硼与碳通量比（B/C）和硼与氧气通量比（B/O）是CR传播的非常重要的探针。单个幂律在不确定性中，B/C比的能量依赖性可以很好地描述到不确定性内约1 TEV/N的单个幂律。这项工作报告了B/C和B/O的直接测量在10 GEV/N到5.6 TEV/N的能量范围内，由Dark Matter粒子资源管理器收集了6年的数据，具有较高的统计数据，并且具有高度控制的系统不确定性。 B/C和B/O比的能量依赖性可以由破碎的幂律模型而不是单个幂律模型很好地拟合，这表明在大约100 GEV/N处的光谱硬化的两个通量比的存在。休息的意义约为Geant4模拟的$5.6σ$和$6.9σ$，对于b/c和b/o，替代Fluka模拟的$4.4σ$和$6.9σ$分别为$6.9σ$。这些结果偏离了星际培养基的常规湍流理论的预测，这表明在不同的尺度或CRS的新型传播效应下，星际培养基（ISM）的湍流特性的变化，应通过抗抗物质颗粒正确地纳入暗物质的间隙检测。
Boron nuclei in cosmic rays (CRs) are believed to be mainly produced by the fragmentation of heavier nuclei, such as carbon and oxygen, via collisions with the interstellar matter. Therefore, the boron-to-carbon flux ratio (B/C) and the boron-to-oxygen flux ratio (B/O) are very essential probes of the CR propagation. The energy dependence of the B/C ratio from previous balloon-borne and space-based experiments can be well described by a single power-law up to about 1 TeV/n within uncertainties. This work reports direct measurements of B/C and B/O in the energy range from 10 GeV/n to 5.6 TeV/n with 6 years of data collected by the Dark Matter Particle Explorer, with high statistics and well controlled systematic uncertainties. The energy dependence of both the B/C and B/O ratios can be well fitted by a broken power-law model rather than a single power-law model, suggesting the existence in both flux ratios of a spectral hardening at about 100 GeV/n. The significance of the break is about $5.6σ$ and $6.9σ$ for the GEANT4 simulation, and $4.4σ$ and $6.9σ$ for the alternative FLUKA simulation, for B/C and B/O, respectively. These results deviate from the predictions of conventional turbulence theories of the interstellar medium, which point toward a change of turbulence properties of the interstellar medium (ISM) at different scales or novel propagation effects of CRs, and should be properly incorporated in the indirect detection of dark matter via anti-matter particles.
