The XGIS instrument on-board THESEUS: Monte Carlo simulations for response, background, and sensitivity

Riccardo Campana; Fabio Fuschino; Claudio Labanti; Sandro Mereghetti; Enrico Virgilli; Valentina Fioretti; Mauro Orlandini; John B. Stephen; Lorenzo Amati

arXiv · 2102.08699

The XGIS instrument on-board THESEUS: Monte Carlo simulations for response, background, and sensitivity

Riccardo Campana·Fabio Fuschino·Claudio Labanti·Sandro Mereghetti·Enrico Virgilli·Valentina Fioretti·Mauro Orlandini·John B. Stephen·Lorenzo Amati

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Abstract

The response of the X and Gamma Imaging Spectrometer (XGIS) instrument onboard the Transient High Energy Sky and Early Universe Surveyor (THESEUS) mission, selected by ESA for an assessment phase in the framework of the Cosmic Vision M5 launch opportunity, has been extensively modeled with a Monte Carlo Geant-4 based software. In this paper, the expected sources of background in the Low Earth Orbit foreseen for THESEUS are described (e.g. diffuse photon backgrounds, cosmic-ray populations, Earth albedo emission) and the simulated on-board background environment and its effects on the instrumental performance is shown.

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Riccardo Campana, Fabio Fuschino, Claudio Labanti, Sandro Mereghetti, Enrico Virgilli, Valentina Fioretti, Mauro Orlandini, John B. Stephen, Lorenzo Amati. 2021-02-17. The XGIS instrument on-board THESEUS: Monte Carlo simulations for response, background, and sensitivity. https://arxiv.org/abs/2102.08699

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