Characterization of a real time dosimetry system using 2D nano and micro-coatings in proton and carbon therapeutic ion beams

Real-time radioluminescence two-dimensional coatings have potential as dosemeters in proton and carbon therapeutic beams. We investigated coatings made of nano and micro-(C₄₄H₃₈P₂)MnCl₄ and (C₃₈H₃₆P₂)MnBr₄ crystals mixed with a water-equivalent substrate. The response of the radioluminescence signal of the coatings along the Bragg curves presented an ionization quenching effect, but less prominent than what has been observed in our previous works using Al₂O₃:X (X = C and C,Mg) coatings. We hypothesize that this results from their lower crystal sizes and effective atomic number (Z_eff). Combined experimental results and Monte Carlo simulations resulted in correction factors to address the linear energy transfer dependence and restore the constant response for particle therapy beams. The quenching correction method was applied to the studied proton and carbon ion beams and yielded the best results for the nano-(C₄₄H₃₈P₂)MnCl_4, coating, followed by the micro-(C₄₄H₃₈P₂)MnCl₄, nano-(C₃₈H₃₆P₂)MnBr₄, and micro-(C₃₈H₃₆P₂)MnBr₄.