dc.description.abstract | In this study, a muon detector which can distinguish the direction of muon is proposed. First, the scintillator detector is used to convert the muon signal into an electronic signal, which is then processed by the readout circuit realized in FPGA. Each scintillator detector include a plastic scintillator and a silicon photomultiplier chip. As the muon passes through the plastic scintillator, it deposits part of its energy in the scintillator. Some fraction of that energy gets converted into photons, which is then converted to a detectable electronic pulse by the silicon photomultiplier chip. The electronic pulse is amplified and converted into a digital signal for the FPGA to receive.
In order to identify whether the muons come from the front side of the detector, two scintillator detectors are placed in parallel at a distance of 30 cm, and the time difference between the muons entering the two detectors is used to identify the direction of muon. In order to distinguish the 1-ns time difference between the two detectors, a multi-phase time-to-digital conversion circuit is realized in FPGA to achieve the desired time resolution. Specifically, the clock frequency is multiplied from 100 MHz to 400 MHz, and it is divided into four phases, which becomes equivalent to a clock frequency of 1600 MHz and reaches a resolution up to 0.625 ns. The proposed scintillator detector is first verified using a pulse generator based on Arduino. It is then used to measure the muon flux at different zenith angles. The measured muon flux decreases with the zenith angle as predicted, and this confirms the proper functioning of the proposed muon detector. | en_US |