The pion-bump structure in the $\gamma$-ray spectrum is a direct proof for the hadronic origin of the $\gamma$ rays, and thus the decisive evidence for the acceleration of hadronic cosmic rays in astrophysical objects. However, the identification of such a spectral feature is limited by the resolution and energy coverage of current $\gamma$-ray instruments. Furthermore, there are unavoidable bremsstrahlung emissions from secondary and primary electrons, which may dominate the $\gamma$-ray emission below the pion-bump. Thus, the study of this $\gamma$-ray emission component can provide unique information on the acceleration and confinement of high-energy particles. In this paper, we studied the predicted $\gamma$-ray spectrum assuming both hadronic or leptonic origin in mid-aged supernova remnants W44, we discuss the detection potential of future MeV missions on these emissions and possible implications.

中文翻译：

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使用未来 MeV 伽马射线探测器精确测量π介子凸块结构


π 介子凸块结构 $\gamma$ 射线谱是强子起源的直接证明 $\gamma$ 射线，因此是天体物理物体中强子宇宙射线加速的决定性证据。然而，这种光谱特征的识别受到当前的分辨率和能量覆盖范围的限制。 $\gamma$ 射线仪器。此外，二次和一次电子不可避免地会产生轫致辐射，这可能会主导 $\gamma$ π介子凸点下方的 射线发射。因此，本研究的 $\gamma$ 射线发射组件可以提供有关高能粒子加速和约束的独特信息。在本文中，我们研究了预测 $\gamma$ 假设强子或轻子起源于中年超新星遗迹 W44，我们讨论了未来 MeV 任务对这些发射的探测潜力和可能的影响。