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arXiv · 2507.00132

On the cosmic-ray distribution in the Galactic Center region: New insights from H.E.S.S

J. Devin·A. Lemière·K. Streil·R. Terrier·C. van Eldik
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Abstract

We performed a spectro-morphological analysis of the diffuse emission in the Galactic center region with H.E.S.S. gamma-ray data. We relied on templates to model the diffuse emissions (the Galactic center ridge and the foreground component) and on a 3D likelihood fitting approach. We first assessed the validity of a continuous injection scenario near the Galactic center by investigating possible deviations from a 1/r profile of the cosmic-ray distribution and potential spectral variations within the Galactic center ridge. We found the data can appropriately be described by a scenario in which a steady source near the Galactic center continuously injects cosmic rays which diffuse through the Central Molecular Zone. We then derived the best-fit spectral parameters of the Galactic center ridge emission and we found a spectral transition near 10-20 TeV.

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J. Devin, A. Lemière, K. Streil, R. Terrier, C. van Eldik. 2025-06-30. On the cosmic-ray distribution in the Galactic Center region: New insights from H.E.S.S. https://arxiv.org/abs/2507.00132

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