Development of a Data Acquisition System for Cosmic Ray Tracking Using SiPM-Based Scintillating Fiber Detectors

The study developed a data acquisition (DAQ) system for cosmic ray tracking, using silicon photomultipliers (SiPMs) and scintillating fibers. The system employs a multi-layer, cross-aligned scintillating fiber detector structure, where the end faces of each fiber are coupled with multi-pixel photon counters (MPPCs), enabling the construction of thousands of readout channels. By measuring the amplitude of the analog signals and dark-count rates of the MPPCs, the threshold is determined. The analog signals are converted into Transistor-Transistor Logic (TTL) signals using a discriminator based on Time-Over-Threshold (TOT) method. The width of TTL signals is recorded by the Time-to-digital convertor (TDC) on the front-end board (FEE). For each single-layer detector, the FEE logs timestamps, positions, and energy of hits. These data are then transmitted to the DAQ board, where a coincidence window is opened to capture incoming events. Upon detecting a valid event, the DAQ board re-encodes the data and uploads it to a host computer. Three-dimensional reconstruction of cosmic ray trajectories was successfully achieved by analyzing spatiotemporal correlations, verifying feasibility, low-cost and high-density readout capability. The design provides a scalable hardware architecture and real-time data processing solution for large-scale particle detection system. Relevant performance tests and physical experimental results will be detailed in the conference presentation.