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arXiv · 2310.07603

Multi-wavelength analysis of the galactic PeVatron candidate LHAASO J2108+5157

G. Pirola·J. Juryšek·M. Balbo·D. Eckert·A. Tramacere·R. Walter
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Abstract

LHAASO J2108+5157 is a recently discovered source, detected in the Ultra-High-Energy band by the LHAASO collaboration. Two molecular clouds were identified in the direction coincident with LHAASO J2108+5157 and, from the spectra reported by LHAASO, there is no sign of an energy cutoff up to 200 TeV. This source makes a promising galactic PeVatron candidate. In 2021, the Large-Sized Telescope prototype (LST-1) of the Cherenkov Telescope Array (CTA) Observatory, collected about 50 hours of quality-selected data on LHAASO J2108+5157. Through these observations, we managed to compute stringent upper limits on the source emission in the multi-TeV band. Together with the analysis of XMM-Newton data and 12 years of Fermi-LAT data, we performed a multi-wavelength study of the source, investigating different possible scenarios of particle acceleration. In this contribution, we will present the results of the analysis, as well as the multi-wavelength modeling, and consequent interpretation of different possible scenarios of emission.

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G. Pirola, J. Juryšek, M. Balbo, D. Eckert, A. Tramacere, R. Walter. 2023-10-11. Multi-wavelength analysis of the galactic PeVatron candidate LHAASO J2108+5157. https://arxiv.org/abs/2310.07603

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