发表机构
Université PSL; Sorbonne Université; CNRS; RWTH Aachen University; Istituto Nazionale di Astrofisica (INAF) – Osservatorio Astrofisico di Arcetri; Institute of Nuclear Physics Polish Academy of Sciences; Université de Paris Cité; Astroparticule et Cosmologie; Istituto Nazionale di Astrofisica (INAF) - Osservatorio di Astrofisica e Scienza dello Spazio (OAS)（巴黎文理研究大学; 索邦大学; 法国国家科学研究中心; 亚琛工业大学; 意大利国家天体物理研究所阿切里天文台; 波兰科学院核物理研究所; 巴黎西岱大学; 高能粒子与宇宙学; 意大利国家天体物理研究所天文与空间科学观测站）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究探讨辐射阶段超新星遗迹对银河宇宙射线谱的贡献，发现若扩散激波加速在辐射期部分有效，其粒子含量可超预算，且辐射阶段影响注入谱形，并可能解释氦质子差异。
AI 中文摘要
近期对大型恒星团和微类星体的甚高能伽马射线观测表明，这些系统能够有效地将粒子加速到甚高能量，这重新引发了关于银河系宇宙射线（CRs）主要来源的争论，并进一步对超新星遗迹（SNRs）的作用产生怀疑，而后者长期以来一直被认为是首要候选者。在这些天体物理环境中，粒子加速通常被认为是由扩散激波加速（DSA）驱动的。因此，DSA能够有效进行的阶段的持续时间问题，对于阐明各种候选宇宙射线源的贡献至关重要。我们旨在阐明SNRs对银河系宇宙射线谱的贡献，以及DSA的预期效率，特别是考虑到在辐射阶段的一部分期间可能发生的粒子加速。我们计算了典型SNRs处由DSA和再加速的先前存在的宇宙射线所产生的总宇宙射线质子含量，并讨论了这两种机制在绝热阶段和早期辐射阶段中的重要性。我们发现，如果在辐射阶段的一部分期间发生DSA和再加速，那么在SNRs处被激发的粒子总含量可以迅速超过解释大部分宇宙射线所需的典型预算。这表明，通常被定义为流体冲压压力转化为宇宙射线的比例的典型瞬时效率，在SNRs演化的大部分时间内需要保持在$\lesssim 1\\%$以下。此外，辐射阶段可以有助于塑造从典型SNRs注入的光谱。我们说明，热核和核心坍缩超新星产生的SNRs之间的差异可能有助于解释所测量的局部星际光谱中氦和质子的差异。
英文摘要
Recent observations of very-high-energy gamma rays from massive stellar clusters and microquasars have demonstrated that these systems can efficiently accelerate particles to very high energies, renewing the debate on the dominant sources of Galactic cosmic rays (CRs) and casting further doubt on the role of supernova remnants (SNRs), long considered the prime candidates. In these astrophysical environments, particle acceleration is generally thought to be driven by diffusive shock acceleration (DSA). The question of the duration of the phase in which DSA can efficiently take place is therefore essential to clarify the contribution of the various candidate CR sources. We aim at clarifying the contribution of SNRs to the Galactic CR spectrum, and the expected efficiency of DSA, especially accounting for possible particle acceleration during part of the radiative phase. We compute the total CR proton content at typical SNRs from DSA and reaccelerated pre-existing CRs, and discuss the importance of these two mechanisms throughout the adiabatic and early radiative phases. We find that if DSA and reacceleration take place during a fraction of the radiative phase, the total content of particles energized at SNRs can quickly overcome the typical budget required to account for the bulk of CRs. This suggests that the typical instantaneous efficiency, often defined as the fraction of fluid ram pressure converted into CRs would need to remain below $\lesssim 1$\% for most of the SNR evolution. Moreover, the radiative phase can contribute to shaping the spectra injected from typical SNRs. We illustrate that the difference between SNRs from thermonuclear and core-collapse SNe could help account for the measured difference in the helium and proton of the local interstellar spectrum.
CommentsAccepted for publication in A&A. 10 pages, 5 Figures
