Speaker
Description
The origin of Galactic Cosmic Rays (GCRs) up to the PeV energy scales remains a significant question in astrophysics. As charged particles, GCRs are deflected by galactic magnetic fields, obscuring their sources. However, the interactions of GCRs with interstellar gas produce a diffuse flux of high-energy gamma rays and neutrinos. This talk will investigate the origins of GCRs by performing a comprehensive multi-messenger analysis. We will employ a range of six theoretical models describing neutral pion decay to predict diffuse gamma-ray emission from the Milky Way. For each model, a corresponding neutrino flux will be derived. These predictions will be tailored to specific regions of the sky, including the inner (25°< l < 100°, ∣b∣ < 5°) and outer (50°< l < 200°, ∣b∣ < 5°) galaxy.
The resulting gamma-ray and neutrino spectra will be compared with the latest observational data from LHAASO and IceCube. This comparative study aims to constrain GCR propagation models and to search for potential unresolved source populations, such as TeV Halos. We find that for most models, TeV halos do not contribute significantly above ~1 TeV; consequently, the respective neutrino emissions are heavily dominated by point sources of unknown origin.