Gamma-Flash: an Experiment to Detect Radiation and Particles in Thunderstorms

Gamma-Flash is an Italian program devoted to the investigation of radiation and particles produced during lightning and thunderstorms. The project is funded by the Italian Space Agency (ASI) and led by the National Institute for Astrophysics (INAF), with the collaboration of numerous institutions and universities. The aim of the project is the study and development of an innovative gamma-ray and neutron detector, and correlative instruments, to be placed onground, at the Climatic Observatory "O. Vittori" on Mt. Cimone (2165 m a.s.l., Northern-Central Italy). In a second phase, the program foresees the development of another payload, to be placed on aircraft for observations of thunderstorms in the air. Gamma-Flash is designed to detect both short-duration transients, such as terrestrial gamma-ray flashes (TGFs), as well as longer-lasting gamma-ray emissions, such as gamma-ray glows, and associated high-energy particle emissions. Main targets of the program are the study of high-energy emissions in thunderstorms, which can have substantial impact in many fields, such as local/global climate change, environmental studies, and atmospheric plasma physics. In addition, the experiment is aimed at the estimate of the susceptibility of electronic systems and devices to TGF-induced ionizing radiation and particles. The investigation of thunderstorm-related high-energy emissions will be supported by a continuous monitoring of the correlated atmospheric scenario, by means of meteorological data analysis on a local scale. The Gamma-Flash group shares cutting-edge expertise in the field of atmospheric physics, high-energy particle and radiation instruments, radiation damage, data analysis, and simulations, taking advantage of more than ten years experience of the ASI AGILE satellite in the field of TGF studies. Gamma-Flash is currently in its design and development phase. The ground-based detector is on its way to the final implementation it will be operative starting from spring 2022. We present an overall description of the Gamma-Flash program, of its detectors, payload, and system design, and of its main scientific objectives.