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arXiv · 1801.06075

Detection of the Characteristic Pion-Decay Signature in the Molecular Clouds

Zhao-Qiang Shen·Yun-Feng Liang·Kai-Kai Duan·Xiang Li·Qiang Yuan·Yi-Zhong Fan·Da-Ming Wei
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Abstract

The $\gamma$-ray emission from molecular clouds is widely believed to have a hadronic origin, while unequivocal evidence is still lacking. In this work, we analyze the Fermi-LAT Pass 8 publicly available data accumulated from 2008 August 4 to 2017 June 29 and report the significant detection of a characteristic $\pi^0$-decay feature in the $\gamma$-ray spectra of the molecular clouds Orion A and Orion B. This detection provides a direct evidence for the hadronic origin of their $\gamma$-ray emission.

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Zhao-Qiang Shen, Yun-Feng Liang, Kai-Kai Duan, Xiang Li, Qiang Yuan, Yi-Zhong Fan, Da-Ming Wei. 2018-01-18. Detection of the Characteristic Pion-Decay Signature in the Molecular Clouds. https://arxiv.org/abs/1801.06075

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