Gamma-ray Astrophysics in the MeV Range: the ASTROGAM Concept and Beyond

Understand

The energy range between about 100 keV and 1 GeV is of interest for a vast class of astrophysical topics.

• In particular, (1) it is the missing ingredient for understanding extreme processes in the multi-messenger era; (2) it allows localizing cosmic-ray interactions with background material and radiation in the Universe, and spotting the reprocessing of these particles; (3) last but not least, gamma-ray emission lines trace the formation of elements in the Galaxy and beyond.
• In addition, studying the still largely unexplored MeV domain of astronomy would provide for a rich observatory science, including the study of compact objects, solar- and Earth-science, as well as fundamental physics.
• The technological development of silicon microstrip detectors makes it possible now to detect MeV photons in space with high efficiency and low background.