Simulation research of a borehole muon detector for deep vein exploration

Natural muons are secondary particles generated through the interaction of the universe's energetic proton stream with the atmosphere. Their remarkable penetration capabilities and broad energy spectrum allow them to traverse thousands of meters underground. This inherent property renders them conducive to imaging via the flux attenuation produced as muons penetrate large objects. In the realm of earth science research, limitations of underground space necessitate the development of novel detection methodologies and instruments for imaging extensive subterranean structures. Presently, researchers worldwide have developed and evaluated numerous muon detectors, predominantly employing drilling techniques. However, existing borehole detectors feature a high number of readout channels and large diameters, resulting in elevated manufacturing expenses and intricate electronic systems. In this study, we propose a small-diameter detector with a reduced number of readout channels, constructed using wedge-section plastic scintillator strips and plastic scintillator arcs, and simulate the detector performance in Geant4. Comparative analysis with traditional rectangular-section plastic scintillator strip designs reveals an enhancement in count rate, employing 176 read electronic channels. The effect of the arc thickness of plastic scintillator on the resolution of the zenith angle of the detector is simulated. The results can provide guidance for the selection of the arc thickness of plastic scintillator. Furthermore, simulated detection of underground gold deposits demonstrates the detector's capability to successfully invert images of subterranean gold deposits within a specified timeframe.