Implementation of the first level trigger for ultra-high-energy cosmic ray (UHECR) detection from space with JEM-EUSO: Initial test results

The JEM-EUSO Collaboration aims to study Ultra-High-Energy Cosmic Ray (UHECR) using a novel approach of looking down from space and using the atmosphere as a large detector to achieve a large effective area and therefore high-statistics on these events for the first time. For this purpose we have been developing a series of pathfinders operating from the ground, high altitude balloons and space, all sharing the same electronics, in particular the central data acquisition system. We report on the implementation and successful testing of the first-level trigger (L1) within the FPGA of the photo-detection module (PDM) board, which processes the signals from 36 64-pixel MAPMTs with a time unit of 2.5 μs to detect the passage of light from cosmic ray generated air-showers.