A study of optically stimulated luminescence in aluminum oxide fibers for the development of a real-time, fiber optic dosimetry system

Scope and method of study. OSL fiber dosimeters show enormous potential for the remote monitoring of radiation doses in a variety of different environments. In particular, the ability for a fiber dosimeter to read the dose received by a patient during radiotherapy in real time during the irradiation procedure is an attractive application for the medical community. Currently the dose received by a patient is measured by dosimeters placed outside the body and the dosimeters are read out after the treatment. Therefore any information about the radiation dose received by the patient is only known after the treatment. Also, many times the dose is calculated from models developed through the irradiation of phantoms used to mimic the human body. Therefore, no actual dose to the patient is ever measured. The radiation exposure that the patient receives is based on what exposure time was needed to deliver the desired dose to a human phantom. In light of this, a method of measuring the actual dose received by a patient while the patient is being exposed is a very desirable tool.;Findings and conclusions. For this project, Al 2O3:C in fiber form was used for the purpose of attachment to a fiber optical cable in order to produce an OSL fiber dosimeter. The excitation/emission properties and radiation-induced luminescence of the Al2O 3:C fibers were studied to determine the most desirable properties for development of an OSL fiber dosimeter. Also, the real-time luminescence signal produced from the fibers during irradiation was measured. This included the characterization of both the radioluminescence and the real-time OSL. Methods of coupling the Al2O3:C fiber to fused silica fiber optic cables in order to maximize transmission of both the stimulation light and the luminescence signal were studied. Next, a real-time readout system for the dosimeters was developed. The readout system was developed to be portable and capable of measuring the absorbed dose and dose rate from the Al 2O3:C fiber probes in real-time over the dose range of interest.