title: Thermoluminescence Response of Ge-Doped Cylindrical-, Flat- and Photonic Crystal Silica-Fibres to Electron and Photon Radiation.
abstract: Study has been made of the thermoluminescence (TL) response of silica-based Ge-doped cylindrical, flat and photonic crystal fibres (referred to herein as PCF-collapsed) to electron (6, 12 and 20 MeV) and photon (6, 10 MV) irradiation and 1.25 MeV γ-rays, for doses from 0.1 Gy to 100 Gy. The electron and photon irradiations were delivered through use of a Varian Model 2100C linear accelerator located at the University of Malaya Medical Centre and γ-rays delivered from a 60Co irradiator located at the Secondary Standard Dosimetry Laboratory (SSDL), Malaysian Nuclear Agency. Tailor-made to be of various dimensions and dopant concentrations (6-10% Ge), the fibres were observed to provide TL yield linear with radiation dose, reproducibility being within 1-5%, with insensitivity to energy and angular variation. The sensitivity dependency of both detectors with respect to field size follows the dependency of the output factors. For flat fibres exposed to 6 MV X-rays, the 6% Ge-doped fibre provided the greatest TL yield while PCF-collapsed showed a response 2.4 times greater than that of the 6% Ge-doped flat fibres. The response of cylindrical fibres increased with core size. The fibres offer uniform response, high spatial resolution and sensitivity, providing the basis of promising TL systems for radiotherapy applications.
authors.affiliation: Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: A
authors.initials: A
authors.lastname: Entezam
authors.affiliation: Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: M U
authors.initials: MU
authors.lastname: Khandaker
authors.affiliation: Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Y M
authors.initials: YM
authors.lastname: Amin
authors.affiliation: Clinical Oncology Unit, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: N M
authors.initials: NM
authors.lastname: Ung
authors.affiliation: Department of Physics, University of Surrey, Guildford, GU2 7XH, United Kingdom.
authors.forename: D A
authors.initials: DA
authors.lastname: Bradley
authors.affiliation: Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: J
authors.initials: J
authors.lastname: Maah
authors.affiliation: Department of Biomedical Imaging, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: M J
authors.initials: MJ
authors.lastname: Safari
authors.affiliation: Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: F
authors.initials: F
authors.lastname: Moradi
mesh_terms: D004307:Dose-Response Relationship, Radiation; D004583:Electrons; D005720:Gamma Rays; D055100:Optical Fibers; D017785:Photons; D011878:Radiotherapy / Q000379:methods; D012822:Silicon Dioxide / Q000737:chemistry / Q000528:radiation effects*; D013819:Thermoluminescent Dosimetry
chemical_list: D012822:Silicon Dioxide