Neutrinos are some of the least understood Standard Model particles. Recently, many more experiments, such as DUNE, SNO+, and T2K, have been looking to dive deeper into these mysterious particles. The EOS experiment, housed at Lawrence Berkeley National Laboratory, hopes to provide an integrated test-bed to develop hybrid neutrino detectors and to support these efforts.

This research focused on the testing of the HVSS (High Voltage Splitter and Summer) prototype board (a part of the EOS experiment), aimed at developing detectors capable of detecting both Cherenkov and scintillation signals simultaneously to detect neutrinos. The study examined the timing characteristics, efficiency, accuracy, and sensitivity of the board in response to photon emissions from a scintillator material activated by a radioactive source.

The research investigated the triggering thresholds of the multi-channel board, which was crucial for triggering on realistic events. The setup utilized test pulses and background noise analysis to establish effective trigger thresholds for optimal signal detection. The study also explored hysteresis effects in the triggering system and investigated the correlation between the analog sum output and input pulse.

Through the testing process, the efficiency of PMT triggering was analyzed under various biasing voltages. The resulting data provided insights into the minimum analog sum signal required to trigger PMT responses consistently. The data also quantified the gain of the PMTs as a function of voltage, determining their performance characteristics in the single-photoelectron regime.

The findings from this research contributed to the ongoing development of the EOS experiment, offering valuable insights into the behavior and performance of the board and the PMTs in a complex experimental setup. The ability to detect both Cherenkov and scintillation signals has promising implications for future neutrino physics experiments, and the results of this study aided in refining the technology required for such endeavors.