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arXiv · 2506.06593

LHAASO protons versus LHAASO diffuse gamma-rays: a consistency check

Luis Enrique Espinosa Castro·Francesco Lorenzo Villante·Vittoria Vecchiotti·Carmelo Evoli·Giulia Pagliaroli
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Abstract

We perform the first direct consistency check between the recently measured proton spectrum at the knee by Large High Altitude Air Shower Observatory (LHAASO) and the collaboration's own high-precision mapping of Galactic diffuse gamma-ray emission. By modeling the hadronic gamma-ray production using the updated cosmic-ray spectra, gas templates and cross-section models, we show that the predicted gamma-ray flux robustly overshoots the LHAASO data in both inner and lateral Galactic regions. This persistent mismatch in both normalization and spectral shape challenges conventional scenarios linking the local cosmic-ray sea to Galactic gamma-ray emission, and calls for a revision of current cosmic ray models in the TeV-PeV sky.

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Luis Enrique Espinosa Castro, Francesco Lorenzo Villante, Vittoria Vecchiotti, Carmelo Evoli, Giulia Pagliaroli. 2025-06-06. LHAASO protons versus LHAASO diffuse gamma-rays: a consistency check. https://doi.org/10.1093/mnrasl%2Fslaf085

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