Data Analysis of PPAC Based on Waveform Sampling

The digital waveform sampling technology is widely used in nuclear physics experiment. It is very important to choose an appropriate sampling frequency. The pulse amplitude discrimination timing method and the constant fraction discrimination timing method were utilized to simulate and analyze the parallel-plate avalanche counter (PPAC) signal with the sampling frequency from 100 MHz to 5 GHz. As the sampling frequency reaches 250-500 MHz, a more accurate position information can be obtained by using the pulse amplitude discrimination timing method. The position distribution Sigma between the pulse amplitude discrimination timing method and the traditional acquisition system is less than 0.15 mm. The position distribution error becomes larger as the sampling frequency is lower than 100 MHz. The high-speed sampling digitizer can be utilized to analyze small signals with signal amplitude less than 20 mV, and the detection efficiency is 4.3% higher than that of traditional PPAC acquisition system.