Dose reconstruction with multiple wavelength analysis in irradiated optical fibres

In order to use radiation induced attenuation in optical fibres for dosimetry in varying conditions, a multiple wavelength analysis method is presented to cope with annealing effects. The approach is demonstrated for low Cl, high OH pure silica fibres at elevated doses up to several kGy and for P-doped fibres at lower total doses of a few tens of Gy. A necessary condition for this approach to work is the existence of different types of defects with associated absorption bands. These bands should also behave differently with respect to the annealing kinetics and underlying dependences.