Evaluation of high-linearity bone radiation detectors exposed to gamma-rays via FTIR measurements.

In radiation physics, the study of new alternative dosimeters is of interest to the growing branch of dosimetric characterization for radiotherapy applications. The goal of this work was to expose bone samples to high doses and evaluate their linearity response to gamma rays. The Fourier Transform Infrared (FTIR) spectrophotometry technique was employed as the evaluation technique, and based on the spectrophotometry absorbance profiles the linearity was assessed based on the following methods: Area Under the Curve (AUC), Wavenumber Method (WM), Partial Component Regression (PCR) and Partial Least-Square Regression (PLSR) methods.

Variance reduction technique in a beta radiation beam using an extrapolation chamber.

This paper aims to show how the variance reduction technique "Geometry splitting/Russian roulette" improves the statistical error and reduces uncertainties in the determination of the absorbed dose rate in tissue using an extrapolation chamber for beta radiation. The results show that the use of this technique can increase the number of events in the chamber cavity leading to a closer approximation of simulation result with the physical problem. There was a good agreement among the experimental measurements, the certificate of manufacture and the simulation results of the absorbed dose rate values and uncertainties.

Study of effective dose of various protocols in equipment cone beam CT.

This study has the purpose of assessing the radiation absorbed dose in organs/tissues and estimating the effective dose using five different models of Cone Beam Computed Tomography equipment using protocols with similar purpose. For this purpose, 26 thermoluminescent dosimeters were inserted in the position of the organs/tissues of a female anthropomorphic phantom. From the measurements the contribution of wT×HT in the organs and tissues the effective dose were calculated.