V. Tatischeff, A. De Angelis, M. Tavani, I. Grenier, U. Oberlack, L. Hanlon, R. Walter, A. Argan, P. von Ballmoos, A. Bulgarelli, I. Donnarumma, Margarita Hernanz, I. Kuvvetli, M. Mallamaci, M. Pearce, A. Zdziarski, A. Aboudan, M. Ajello, G. Ambrosi, D. Bernard, E. Bernardini, V. Bonvicini, A. Brogna, M. Branchesi, C. Budtz-Jorgensen, A. Bykov, R. Campana, M. Cardillo, S. Ciprini, P. Coppi, P. Cumani, R. M. Curado da Silva, D. De Martino, R. Diehl, M. Doro, V. Fioretti, S. Funk, G. Ghisellini, F. Giordano, J. E. Grove, C. Hamadache, D. H. Hartmann, M. Hayashida, J. Isern, G. Kanbach, J. Kiener, J. Knodlseder, C. Labanti, P. Laurent, M. Leising, O. Limousin, F. Longo, K. Mannheim, M. Marisaldi, M. Martinez, M. N. Mazziotta, J. E. McEnery, S. Mereghetti, G. Minervini, A. Moiseev, A. Morselli, K. Nakazawa, P. Orleanski, J. M. Paredes, B. Patricelli, J. Peyre, G. Piano, Martin Pohl, R. Rando, M. Roncadelli, F. Tavecchio, D. J. Thompson, R. Turolla, A. Ulyanov, A. Vacchi, X. Wu, A. Zoglauer

• e-ASTROGAM is a concept for a breakthrough observatory space mission carrying a gamma-ray telescope dedicated to the study of the non-thermal Universe in the photon energy range from 0.15 MeV to 3 GeV. The lower energy limit can be pushed down to energies as low as 30 keV for gamma-ray burst detection with the calorimeter. The mission is based on an advanced space-proven detector technology, with unprecedented sensitivity, angular and energy resolution, combined with remarkable polarimetric capability. Thanks to its performance in the MeV-GeV domain, substantially improving its predecessors, e-ASTROGAM will open a new window on the non-thermal Universe, making pioneering observations of the most powerful Galactic and extragalactic sources, elucidating the nature of their relativistic outflows and their effects on the surroundings. With a line sensitivity in the MeV energy range one to two orders of magnitude better than previous and current generation instruments, e-ASTROGAM will determine the origin of key isotopes fundamental fore-ASTROGAM is a concept for a breakthrough observatory space mission carrying a gamma-ray telescope dedicated to the study of the non-thermal Universe in the photon energy range from 0.15 MeV to 3 GeV. The lower energy limit can be pushed down to energies as low as 30 keV for gamma-ray burst detection with the calorimeter. The mission is based on an advanced space-proven detector technology, with unprecedented sensitivity, angular and energy resolution, combined with remarkable polarimetric capability. Thanks to its performance in the MeV-GeV domain, substantially improving its predecessors, e-ASTROGAM will open a new window on the non-thermal Universe, making pioneering observations of the most powerful Galactic and extragalactic sources, elucidating the nature of their relativistic outflows and their effects on the surroundings. With a line sensitivity in the MeV energy range one to two orders of magnitude better than previous and current generation instruments, e-ASTROGAM will determine the origin of key isotopes fundamental for the understanding of supernova explosion and the chemical evolution of our Galaxy. The mission will be a major player of the multiwavelength, multimessenger time-domain astronomy of the 2030s, and provide unique data of significant interest to a broad astronomical community, complementary to powerful observatories such as LISA, LIGO, Virgo, KAGRA, the Einstein Telescope and the Cosmic Explorer, IceCube-Gen2 and KM3NeT, SKA, ALMA, JWST, E-ELT, LSST, Athena, and the Cherenkov Telescope Array.…