Speaker
Description
The Sun is an important source of high-energy gamma rays produced by interactions between Galactic cosmic rays and the solar atmosphere. However, discrepancies between theoretical predictions and observations suggest that the role of solar magnetic fields in gamma-ray production is not yet fully understood. In this work, we investigate the effects of localized solar magnetic structures on cosmic-ray proton transport and gamma-ray emission through numerical simulations. We construct a solar magnetic field model incorporating magnetic flux ropes and magnetic arcades, and implement it into G4SOLAR, a simulation framework based on Geant4. The simulations account for cosmic-ray proton propagation, hadronic interactions with the solar atmosphere, and the subsequent production of secondary gamma rays. We further compare the simulated gamma-ray spectra with observations from Fermi-LAT and preliminary results from LHAASO-WCDA. The observational results indicate that solar gamma-ray emission extends into the TeV energy range, while the simulated spectra suggest that localized magnetic structures can significantly enhance gamma-ray production, particularly at high energies. These findings highlight the importance of small-scale solar magnetic fields in shaping the gamma-ray spectrum and provide new insights into the physical mechanisms responsible for high-energy solar gamma-ray emission.
