Performance of the EUSO-BALLOON Front-End Electronics

Here the performance of EUSO-BALLOON front-end electronics with dedicated detector elements will be reported. EUSO-BALLOON is a balloon-borne pathfinder of the space-borne fluorescence detector JEM-EUSO (Extreme Universe Space Observatory on board Japanese Experimental Module) on board the International Space Station. The goal of EUSO-BALOON is to perform as a technological demonstrator of JEM-EUSO, to study the background and the detection of an atmospheric shower in a series of launches starting in 2014. The EUSO-BALLOON focal surface consists of one Photo Detector Module (PDM) while the focal surface of JEM-EUSO will consist of 137 PDMs which corresponding to roughly 5,000 64-channel Multi-Anode Photomultiplier Tubes (MAPMTs). One PDM consists of 9 Elementary Cell units (EC_units). Each EC_unit contains 4 MAPMTs and a set of PCBs used to supply high voltages to the MAPMTs and to read out the output signals. These signals are transmitted to the front-end electronics, the EC-ASIC boards each of which contains 6 SPACIROC ASICs which has been developed for JEM-EUSO. To be operated in a space environment with a limited power budget, and covering a wide dynamic range for extreme energy cosmic ray (>5x10ˆ19 eV) observation, the ASIC is designed to perform single photon counting in a dynamic range of 1 photoelectron (PE) to 300 PEs/pixel/2.5 μs, with double pulse resolution of 30 ns, and low power consumption (<1 mW/ch). During the year 2013, the flight model EC_units and EC_ASIC PCBs were produced and the performance was successfully tested and confirmed.