Multiwavelength SED of LHAASO J2108+5157 with hadronic models of emission. Observations with different instruments are represented by datapoints of different colors: XMM-Newtonr = 16′ (blue), Fermi-LAT (green), LST-1 (red), and LHAASO-KM2A (purple). The best-fitting hadronic model of VHE-UHE emission (solid line) with fixed spectral index of the proton PL distribution α = 2.75 has γ_min = 1.6 × 10⁵ for both clouds. Dashed line represents the total neutrino flux for both clouds. Black and red dash-dotted lines represent the synchrotron emission of secondary particles for cloud 1 and cloud 2, respectively. The gray dash-dotted line represents the π⁰ decay emission model with α = 2 and γ_min = 1 shown for reference (Cao et al. 2021a).