The X-Gamma Imaging Spectrometer (XGIS) onboard THESEUS
Abstract
A compact and modular X and gamma-ray imaging spectrometer (XGIS) has been designed as one of the instruments foreseen onboard the THESEUS mission proposed in response to the ESA M5 call. The experiment envisages the use of CsI scintillator bars read out at both ends by single-cell 25 mm2 Silicon Drift Detectors. Events absorbed in the Silicon layer (lower energy X rays) and events absorbed in the scintillator crystal (higher energy X rays and gamma -rays) are discriminated using the on-board electronics. A coded mask provides imaging capabilities at low energies, thus allowing a compact and sensitive instrument in a wide energy band (∼2 keV up to ∼20 MeV). The instrument design, expected performance and the characterization performed on a series of laboratory prototypes are discussed.
- Publication:
-
Memorie della Societa Astronomica Italiana
- Pub Date:
- 2018
- DOI:
- 10.48550/arXiv.1802.01674
- arXiv:
- arXiv:1802.01674
- Bibcode:
- 2018MmSAI..89..137C
- Keywords:
-
- Gamma-rays:instruments;
- Gamma-ray-bursts:detection;
- Telescopes:X-rays;
- Astrophysics - Instrumentation and Methods for Astrophysics
- E-Print:
- To be published in the Proceedings of the THESEUS Workshop 2017 (http://www.isdc.unige.ch/theseus/workshop2017.html), Journal of the Italian Astronomical Society (Mem.SAIt), Editors L. Amati, E. Bozzo, M. Della Valle, D. Gotz, P. O'Brien. Details on the THESEUS mission concept can be found in the white paper Amati et al. 2017 (arXiv:171004638) and Stratta et al. 2017 (arXiv:1712.08153)