Fast Front-end Electronics Development for the Cylindrical Trigger Hodoscope in COMET Phase-I

The COMET (COherent Muont-to-Electron Transition) experiment aims to search for neutrinoless conversion of a muon to an electron. This process is extremely suppressed in the Standard Model of particle physics with a minimum extension of neutrino oscillations. On the other hand, many new physics modesl predict the huge enhancement in the conversion rate of muton-to-electron converson. In COMETPhase-I, we will investigate this process with a sensitivity 100 times better than the current upper limit. In the experiment, a Cylindrical Trigger Hodoscope (CTH) plays an essential role by providing a primary trigger signal as well as determining the timing measurement for signal electrons as precise as 1 ns. Due to high hit rate and high radiation environment, the CTH requires its dedicated front-end electronicswhich is operational up to a few MHz pile-up rate and tolerable agains the total fluence of neutrons up to 10¹¹ n/cm². Based on a series of neutron irradiation tests and prototyping, the design of entire electronics system has been fixed and the first batch of each component has been produced. In this talk, we report the detailed design of electronics and the results of tests that have been conducted.