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X-ray detectors are commonly used for medical, crystallography and space physics applications. Most of the current x-ray detectors use cadmium zinc telluride (CZT) as the active medium. This report investigates high density semiconducting and scintillating glasses as potential alternatives to CZT. For the semiconducting glasses, samples composed of xCuO–((1−x)/2)PbO–((1−x)/2)V2O5 and xFeO–((1−x)/2)PbO–((1−x)/2)V2O5, for the scintillating glasses, samples composed of xGd2O3+yWO3+(1−x−y)2H3BO3, doped with 1–6% Eu3+ or Tb3+, were investigated in this study. The glass-making conditions, density, Raman spectroscopy analysis, photoluminescence excitation and emission spectra, as well as conductivity measurements performed on various samples, are reported. The interaction of x-rays with all the glass samples was simulated using GATE software, and their mass attenuation coefficients were calculated and compared with CZT.

 

Abstract A 3-D dosimeter fills the need for treatment plan and delivery verification required by every modern radiation-therapy method used today. This report summarizes a proof-of-concept study to develop a water-equivalent solid 3-D dosimeter that is based on novel radiation-hard scintillating material. The active material of the prototype dosimeter is a blend of radiation-hard peroxide-cured polysiloxane plastic doped with scintillating agent P-Terphenyl and wavelength-shifter BisMSB. The prototype detector was tested with 6 MV and 10 MV x-ray beams at Ohio State University’s Comprehensive Cancer Center. A 3-D dose distribution was successfully reconstructed by a neural network specifically trained for this prototype. This report summarizes the material production procedure, the material’s water equivalency investigation, the design of the prototype dosimeter and its beam tests, as well as the details of the utilized machine learning approach and the reconstructed 3-D dose distributions. 

Protons deposit the majority of their energy at the end of their lifetimes, characterized by a Bragg peak. This makes proton therapy a viable way to target cancerous tissue while minimizing damage to surrounding healthy tissue. However, in order to utilize this high precision treatment, greater accuracy in tumor imaging is needed. An approximate uncertainty of ±3% exists in the current practice of proton therapy due to conversions between x-ray and proton stopping power. An imaging system utilizing protons has the potential to eliminate that inaccuracy. This study focuses on developing a proof of concept proton-imaging detector built with a high-density glass scintillator.