Speaker
Description
Measurements of secondary cosmic radiation in the lower atmosphere provide important insight into particle acceleration processes in thunderstorms and high-energy atmospheric physics. Observations performed with the MOSAIC detector, a compact four-layer silicon strip tracking system designed for directional measurements of charged particles, will be reported.
The detector has been deployed at high-altitude mountain observatories to study variations in secondary cosmic radiation under different atmospheric conditions. In 2023, MOSAIC operated at the Lomnický štít Observatory, where it recorded a thunderstorm ground enhancement (TGE) event that ended with lightning. The tracking capability of the detector allows discrimination of particle trajectories and contributes to the study of angular and temporal characteristics of such events.
To extend the detection area and enable coincidence measurements over a larger footprint, the LAMA (Large-Area Mosaic Array) has been developed. LAMA consists of 36 time-synchronized MOSAIC units distributed over an area of 4 × 4 m². The array was installed in summer 2024 at Milešovka.
Ongoing analysis focuses on characterizing background fluxes, space weather and atmospheric modulation effects, and the search for short enhancements in fluxes of electrons and muons. The use of compact tracking detectors in a distributed array provides a platform for studies of the spatial and temporal structure of atmospheric ionizing radiation.