发表机构
Instituto de Astrofísica de Canarias; Universidad de La Laguna; Universidad Autónoma de Madrid; Instituto de Física Teórica UAM-CSIC; INFN Sezione di Pisa（加那利天体物理研究所; 拉帕鲁尼亚大学; 马德里自治大学; 马德里自治大学-西班牙国家科研中心理论物理研究所; 意大利国家核物理研究所比萨分部）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
通过分析费米-LAT 17年伽马射线数据，发现银道面20-30 GeV处存在与本地CR核特征吻合的全球CR能谱拐折，为CR起源与传播研究提供关键证据。
AI 中文摘要
我们分析了费米-LAT（Fermi-LAT）17年的数据，以研究银道面的弥散伽马射线辐射及其与宇宙射线（CR）传播的关联。在考虑相关的仪器系统误差后，我们发现了~20-30 GeV处存在一个能谱拐折的决定性证据，该拐折存在于银盘内部，其Δχ²为39.78（全局4.44σ）。该特征的能量和幅度与本地宇宙射线核中观测到的能谱特征显著吻合，表明它是银盘的全球属性而非局部现象。测得的斜率变化Δγ≈0.20，与本地CR数据以及CR扩散机制从柯尔莫哥洛夫（Kolmogorov）湍流到克拉赫南（Kraichnan）湍流转变的预期一致。我们的结果提供了有力证据，表明银盘的弥散伽马射线辐射在高达100 GeV时由π⁰衰变辐射主导。这些发现为CR能谱硬化的起源以及CR在整个银河系中的传播提供了关键见解，并说明这种多信使方法可用于探测CR能谱中特征的起源，如长期研究的CR膝区。
英文摘要
We analyze 17 years of Fermi-LAT data to study the diffuse $γ$-ray emission along the Galactic plane and its connection to cosmic-ray (CR) propagation. Accounting for correlated instrumental systematics, we find decisive evidence for a spectral break at $\sim20-30$ GeV, present across the inner Galactic disk, with a preference of $Δχ^2=39.78$ ($4.44 σ$ global). The energy and amplitude of this feature are in striking agreement with the spectral feature observed in local CR nuclei, indicating that it is a global property of the Galactic disk rather than a local phenomenon. The measured slope change, $Δγ\simeq 0.20$, is consistent with local CR data and with expectations from a transition in the CR diffusion regime from Kolmogorov to Kraichnan turbulence. Our results provide strong evidence that diffuse $γ$-ray emission along the Galactic disk is dominated by $π^0-$decay emission up to a hundred GeV. These findings provide key insights into the origin of the CR spectral hardening and the propagation of CRs throughout the Galaxy, and illustrate how this multimessenger approach can be used to probe the origin of features in the CR spectra, such as the long-studied CR Knee.
Comments5 pages, 2 figures
