title: Characterization of scintillating X-ray optical fiber sensors.
abstract: The paper presents a set of tests carried out in order to evaluate the design characteristics and the operating performance of a set of six X-ray extrinsic optical fiber sensors. The extrinsic sensor we developed is intended to be used as a low energy X-ray detector for monitoring radiation levels in radiotherapy, industrial applications and for personnel dosimetry. The reproducibility of the manufacturing process and the characteristics of the sensors were assessed. The sensors dynamic range, linearity, sensitivity, and reproducibility are evaluated through radioluminescence measurements, X-ray fluorescence and X-ray imaging investigations. Their response to the operating conditions of the excitation source was estimated. The effect of the sensors design and implementation, on the collecting efficiency of the radioluminescence signal was measured. The study indicated that the sensors are efficient only in the first 5 mm of the tip, and that a reflective coating can improve their response. Additional tests were done to investigate the concentricity of the sensors tip against the core of the optical fiber guiding the optical signal. The influence of the active material concentration on the sensor response to X-ray was studied. The tests were carried out by measuring the radioluminescence signal with an optical fiber spectrometer and with a Multi-Pixel Photon Counter.
authors.affiliation: National Institute Laser, Plasma and Radiation Physics, 409 Atomiştilor St., Măgurele RO-077125, Romania. dan.sporea@inflpr.ro.
authors.forename: Dan
authors.initials: D
authors.lastname: Sporea
authors.affiliation: National Institute Laser, Plasma and Radiation Physics, 409 Atomiştilor St., Măgurele RO-077125, Romania. laura.mihai@inflpr.ro.
authors.forename: Laura
authors.initials: L
authors.lastname: Mihai
authors.affiliation: Horia Hulubei" National Institute of Physics and Nuclear Engineering, 30 Reactorului St., Măgurele RO-077125, Romania. vata@nipne.ro.
authors.forename: Ion
authors.initials: I
authors.lastname: Vâţă
authors.affiliation: Optical Fibre Sensors Research Centre, ECE Department, University of Limerick, Limerick, Ireland. denis.mccarthy@emc.com.
authors.forename: Denis
authors.initials: D
authors.lastname: McCarthy
authors.affiliation: Optical Fibre Sensors Research Centre, ECE Department, University of Limerick, Limerick, Ireland. Sinead.OKeeffe@ul.ie.
authors.forename: Sinead
authors.initials: S
authors.lastname: O'Keeffe
authors.affiliation: Optical Fibre Sensors Research Centre, ECE Department, University of Limerick, Limerick, Ireland. Elfed.Lewis@ul.ie.
authors.forename: Elfed
authors.initials: E
authors.lastname: Lewis