Abstract
This paper reports the assessment of commercial Ge-doped fibres as a potential dosimeter. The thermoluminescence response was measured for 4 fibre types: commercial multi-mode germanium doped core fibres at 4% and 6% weight Ge doping; single mode fibre with a 17% Ge and 1% B (GeB) doped core; and undoped silica fibre. The fibres were subjected to beta irradiation (Sr-90/Y-90), heated from room temperature to 400 degrees C. The 6% Ge doped fibre exhibited sensitivity of 7.7 +/- 0.2 counts.mm(-1).Gy(-1).mu m(-2), greater than the 4% Ge-doped and GeB fibres by factors of 9.2 and 1.3 respectively. All the core-doped fibres (Ge, GeB) showed a high linear response across the dose range 1-10 Gy (R-2 = 0.99). Increasing the Ge concentration from 4 to 17% lowered the temperature of the glow curve peak from 317 degrees C to 248 degrees C. The glow curve for both Ge doped core fibres were analysed using a computerised glow curve deconvolution (CGCD) in TolAnal software. When including Ge dopants, the estimated trap depth for five sub-peaks in the Ge doped fibre was reported between 0.6 and 1.54 eV.