The all-sky medium energy gamma-ray observatory

The All-sky Medium Energy Gamma-ray Observatory (AMEGO) is an Astrophysics Probe mission concept designed to explore the MeV sky. It has a unique capability to cover with high sensitivity both the Compton and pair conversion regimes from ∼ 200 keV to > 10 GeV . To date the MeV regime was explored with significantly less sensitivity with respect to the nearby energy bands, and promises a rich return similar to what Fermi-LAT achieved in the GeV band. The AMEGO instrument features an anti-coincidence detector, a double-sided Silicon microstrip tracker with analog readout, a segmented CZT calorimeter optimized for the Compton regime, and a segmented CsI calorimeter optimized for the pair regime. This design choice provides substantial performance improvements relative to CGRO-COMPTEL and Fermi-LAT in the overlapping energy bands. In particular, the detector is tailored to the challenging task of imaging Compton events with unprecedented resolution.