A Monte-Carlo-based study of a single-2D-detector proton-radiography system

Area of Science:

• Medical imaging physics
• Particle physics instrumentation

Background:

• Proton radiography (pRG) offers potential for precise material characterization.
• Accurate measurement of water-equivalent path length (WEPL) and relative stopping power (RSP) is crucial for various scientific applications.

Purpose of the Study:

• To evaluate the feasibility of a proton radiography system utilizing a single thin pixelated detector.
• To assess the system's capability for accurate WEPL and RSP measurements.

Main Methods:

• A Monte Carlo simulation using Geant4 modeled a pRG system with a single pixelated detector.
• Calculated 2D distributions of energy deposition and proton fluence to determine average stopping power.
• Calibrated system response against residual range in water to derive WEPL and RSP distributions.

Main Results:

• The derived RSP values from the detector simulations closely matched reference values for various materials.
• Agreement between the detector-derived RSPs and reference RSPs was within 1% for both human-tissue and non-human-tissue-equivalent materials.

Conclusions:

• A proton radiography system employing a single thin pixelated detector is feasible.
• The proposed system can predict relative stopping power with a high accuracy of 1%.