Update and finalization of a fibered on-line dosimetry system based on optically stimulated phosphorescent materials Application to dose measurement in radiation therapy and beam monitoring

Wherever radiations are used, for medicine, industrial applications or research, the amount of energy deposited per unit mass (absorbed dose) has to be quantified. The usual Methods used to quantify the dose, that is dosimetry are reviewed. The overall context in both radiation therapy and high energy physics led to the elaboration of a book of specifications for the development of a novel type of on-line dosimetry. It is based on the quantification of the luminescence emitted by an optically stimulated phosphorescent material deported by an optical fiber. Principles and applications relatives to these techniques are presented in chapters 2 and 3. Chapter 4 describes a novel, easy of use, robust and flexible dosimetry system. The first experimental results exhibit an excellent linearity of the response with dose (0.01 to 6 Gy), measurement repeatability less than 2%, a high sensitivity to radiation and an error on dose measurement less than 5%. Preliminary system qualification for dose measurement during both radiation therapy treatments and beam monitoring in high energy physics facilities (CERN and DESY) gave encouraging results since the system meets some of the requirements specific to each kind of application. Thus, the characterization of structural and luminescence properties of the phosphorescent material doped with boron, with aim of application for the on-line dosimetry in mixed radiation field neutron / gamma may explain the drop of luminescence previously observed. (author)