Multi-messenger emission from astrophysical sources hidden in γ-rays Dafne Guetta, Angela Zegarelli, Silvia Celli, Silvia Gagliardini, Irene Di Palma and Imre Bartos EPJ Web Conf., 319 (2025) 03002 Published online: 06 March 2025 DOI: 10.1051/epjconf/202531903002