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arXiv · 2512.16009

Exploring the Galactic Plane: A Comparative Study of Fermi-LAT Sources and HESS's Non-Detection at TeV Energies

François Brun·Baptiste Le Nagat-Neher·Marianne Lemoine-Goumard·Marie-Hélène Grondin·Paul Fauverge
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Abstract

The HESS Galactic Plane Survey (HGPS), published in 2018, presented a decade of very-high-energy (VHE) gamma-ray observations along the Galactic plane. This study was accompanied by the release of several maps in FITS format, offering a detailed view of the region. The flux upper-limits from these HGPS maps can be compared to the high-energy (HE) spectra of sources catalogued by the Fermi-LAT in the same region. For some sources, extrapolating the Fermi-LAT flux into the VHE range predicts flux values exceeding the upper-limits set by HESS. In this work, we present the results of this comparison and highlight the sources that are of particular interest for future VHE observations.

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François Brun, Baptiste Le Nagat-Neher, Marianne Lemoine-Goumard, Marie-Hélène Grondin, Paul Fauverge. 2025-12-17. Exploring the Galactic Plane: A Comparative Study of Fermi-LAT Sources and HESS's Non-Detection at TeV Energies. https://doi.org/10.22323/1.501.0584

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