Study of charge dynamics in THGEM-based detectors — a numerical approach

Muography [1] utilizes cosmic muon interactions to image and analyze material properties. Electromagnetic interactions cause cosmic muon trajectories to deviate [2] (or even absorbed [1]), with the magnitude of deviation (absorption) reflecting the material's characteristics. These modifications in cosmic muons can be utilized to generate images of a target object in their path and infer its material composition and geometry. Position-sensitive detectors, such as various gaseous ionization detectors, solid-state detectors, emulsion-based detectors are typically used to track cosmic muons to fulfil this purpose. THick Gaseous Electron Multipliers (THGEM) [3], that are robust and relatively easily fabricated [4], can monitor muon tracks effectively. This numerical study has been initiated to evaluate the performance and suitability THGEM-based detectors in this context, focusing on key parameters like gain, charging up and discharge probability. A hybrid numerical model integrates HEED, MAGBOLTZ, and COMSOL for simulating charge dynamics and detector response. A Python interface automates necessary repetitive simulations. Thus, this work provides a framework for optimizing THGEM detectors for imaging applications.