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arXiv · 2406.03691

Precise measurement of pion-bump structure using future MeV gamma-ray detectors

Jiahao Liu·Bing Liu·Ruizhi Yang
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Abstract

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.

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Jiahao Liu, Bing Liu, Ruizhi Yang. 2024-06-06. Precise measurement of pion-bump structure using future MeV gamma-ray detectors. https://arxiv.org/abs/2406.03691

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