Monte Carlo simulation of a cabinet kilovoltage X-ray irradiator

We present a rigorously defined dosimetric Monte Carlo (MC) model of the MultiRad225 kilovoltage X-ray irradiator, which is validated using experimental techniques. Previous MC studies performed with the MultiRad225 lacked rigorous dosimetric validation.

Experimental measurements are conducted with an ionization chamber and radiochromic film with beam energies of 119, 160, and 200 kV. MC simulations are conducted mimicking each experiment. Both beam quality (half-value layer, HVL) and quantity (dose rate) are assessed with these methods.

MC simulated dose rates and HVL values show close agreement with experimental results across varying source-to-surface distances (SSD) for each beam energy with most dose rate simulations falling within 5% of the experimentally measured values.

This work provides a validated MC model as a foundation for future studies with the MultiRad225. The MC model utilizes a comprehensive geometry which accurately captures relevant physical phenomena.