Crystal Eye: all sky MeV monitor with high precision real-time localization
Roberto Aloisio, Uygar Atalay, Biswajit Banerjee, Felicia C. T. Barbato, Elisabetta Bissaldi, Marica Branchesi, Fiamma Capitanio, Elisabetta Casilli, Roberta Colalillo, Ivan De Mitri, Alessio De Santis, Adriano Di Giovanni, Mateo Fernandez Alonso, Giulio Fontanella, Fabio Gargano, Fabio Garufi, Fausto Guarino, Dimitrios Kyratzis, Herman Lima, Francesco Loparco, Francesco Longo, Riccardo Martinelli, Teresa Montaruli, Gor Oganesyan, Javier Rico, Filippo Santoliquido, Ritabrata Sarkar, Pierpaolo Savina, Iqra Siddique, Aleksei Smirnov, Matteo Tambone, Antonella Tarana, Andrii Tykhonov, Laura Valore, A. A. Vigliano, Libo Wu
Published: 2025/7/26
Abstract
Crystal Eye is a space-based all-sky monitor optimized for the autonomous detection and localization of transients in the 10 keV to 30 MeV energy range, a region where extensive observations and monitoring of various astrophysical phenomena are required. By focusing on the operating environment and its impact on the observation process, we optimized the detector design and assessed its scientific potential. We explored the use of novel techniques to achieve the science goals of the experiment. We assumed the orbit of a potential future mission at approximately 550 km altitude near the equatorial region with a 20{\deg} inclination. In such an orbit, the main background contributions for this kind of detector are from different particles and radiation of cosmic origin and secondaries produced by their interaction in the Earth's atmospheric and geomagnetic environment. We studied the response of the detector in this background environment, using the Geant4 Monte Carlo simulation toolkit. We also calculated other detector performance parameters to estimate its scientific capabilities. The detector effective area and efficiency are calculated for low energy gamma-ray sources and used to estimate its sensitivity to short-duration transient sources. The calculation shows a better effective area and sensitivity by several factors compared to existing instruments of similar type. A method is also developed and discussed to estimate the online transient-localization performance of the detector, suggesting a better localization precision by about an order of magnitude than those typically reported by existing gamma-ray monitors. We present here the simulation study and results of an innovative detector design concept that can make a significant contribution in the multi-messenger era. Moreover, this study can be useful as a technical reference for similar future experiments.