A novel technique to detect special nuclear material using cosmic rays

摘要

Resistive plate chambers (RPCs) are widely used in high energy physics forboth tracking and triggering purposes, due to their excellent time resolution,rate capability, and good spatial resolution. RPCs can be producedcost-effectively on large scales, are of rugged build, and have excellentdetection efficiency for charged particles. Our group has successfully builta muon scattering tomography (MST) prototype, using 12 RPCs to obtain trackinginformation of muons going through a target volume of ∼ 50 cm × 50 cm × 70 cm,reconstructing both the incoming and outgoing muon tracks. The required spatialgranularity is achieved by using 330 readout strips per RPC with 1.5 mm pitch.The RPCs have shown an efficiency above 99% and an estimated intrinsic resolutionbelow 1.1 mm. Due to these qualities, RPCs serve as excellent candidates for usagein volcano radiography.