Abstract Although supernova remnants remain the main suspects as sources of Galactic cosmic rays up to the knee, the supernova paradigm still has many loose ends. The weakest point in this construction is the possibility that individual supernova remnants can accelerate particles to the rigidity of the knee, ~ 106 GV. This scenario heavily relies upon the possibility to excite current driven non-resonant hybrid modes while the shock is still at the beginning of the Sedov phase. These modes can enhance the rate of particle scattering thereby leading to potentially very–high maximum energies. Here we calculate the spectrum of particles released into the interstellar medium from the remnants of different types of supernovae. We find that only the remnants of very powerful, rare core–collapse supernova explosions can accelerate light elements such as hydrogen and helium nuclei, to the knee rigidity, and that the local spectrum of cosmic rays directly constrains the rate of such events, if they are also source of PeV cosmic rays. On the other hand, for remnants of typical core–collapse supernova explosions, the Sedov phase is reached at late times, when the maximum energy is too low and the spectrum at very–high energies is very steep, being mostly produced during the ejecta dominated phase. For typical thermonuclear explosions, resulting in type Ia supernovae, we confirm previous findings that these objects can only produce cosmic rays up to ≲ 105 GeV. The implications for the overall cosmic ray spectrum observed at the Earth and for the detection of PeVatrons by future gamma–ray observatories are discussed.

中文翻译：

---

银河系pevatrons的低比率

摘要 尽管超新星遗迹仍然是直到膝部的银河宇宙射线源的主要嫌疑人，但超新星范式仍然有许多未解决的问题。这种结构的最弱点是个别超新星遗迹可能将粒子加速到膝盖的刚度，约 106 GV。这种情况在很大程度上依赖于在冲击仍处于 Sedov 阶段开始时激发电流驱动的非谐振混合模式的可能性。这些模式可以提高粒子散射率，从而导致潜在的非常高的最大能量。在这里，我们计算了从不同类型超新星的残余物释放到星际介质中的粒子光谱。我们发现只有非常强大的残余，罕见的核心坍缩超新星爆炸可以将氢和氦原子核等轻元素加速到膝盖刚度，并且宇宙射线的局部光谱直接限制了此类事件的发生率，如果它们也是 PeV 宇宙射线的来源。另一方面，对于典型的核心坍缩型超新星爆炸的残余物，Sedov 阶段是在晚期达到的，此时最大能量太低，极高能量的光谱非常陡峭，主要是在喷射物占主导地位期间产生的。阶段。对于典型的热核爆炸，导致 Ia 型超新星，我们证实了之前的发现，即这些物体只能产生高达 ≲ 105 GeV 的宇宙射线。讨论了对地球观测到的整个宇宙射线光谱的影响以及对未来伽马射线天文台探测 PeVatron 的影响。