Data acquisition system of CANDLES detector for double beta decay experiment

The observation of neutrino-less double beta decay (0νββ) will prove existence of a massive Majorana neutrino. For a sensitive measurement of the neutrino mass, we have developed a new detector system CANDLES, which features CaF₂(pure) scintillators. The CANDLES system needs a low background measurement because 0νββ is a very rare decay. In order to reach the low background measurement, we introduced characteristic flash ADCs in the system. Besides the flash ADC, we developed a trigger system for the CaF₂(pure) events. Signal processing for the data readout and trigger is in a FPGA. In this paper, we present the data acquisition system including the characteristic flash ADC and the trigger system for the CANDLES system.