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Simulation of the AGILE gamma-ray imaging detector performance: part I

Francesco Longo·Veronica Cocco·Marco Tavani
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Abstract

We present in this paper the results of a comprehensive GEANT simulation of the Gamma-Ray Imaging Detector (GRID) being developed for the AGILE space astrophysics mission. The GRID is designed to be sensitive in the 30 MeV - 50 GeV energy range, with excellent imaging and timing capabilities, and with a very large field-of-view (~3 sr). In this paper (Paper I) we present the GRID baseline geometry, a model for the charged particle and albedo-photon backgrounds for an equatorial orbit of 550-600 km altitude, and the main results of the first level (Level-1 Trigger) on-board data processing. Our simulations show that the GRID Level-1 data processing is expected to be capable of decreasing by a factor of ~ 20 the charged particle background (from \~2 kHz to below 100 Hz), and by a factor of ~ 30 the albedo-photon background. The gamma-ray photon detection efficiency by the imaging GRID is simulated to be particularly efficient, varying between 39% and 17% depending on photon energies and incident directions.

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Francesco Longo, Veronica Cocco, Marco Tavani. 2002-02-12. Simulation of the AGILE gamma-ray imaging detector performance: part I. https://doi.org/10.1016/s0168-9002(01)02159-3

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