TY - CONF A1 - Wosniok, Aleksander A1 - Sporea, D. A1 - NeguĊ£, D. A1 - Krebber, Katerina T1 - Gamma radiation influence on silica optical fibers measured by optical backscatter reflectometry and Brillouin sensing technique N2 - We have studied the influence of gamma rays on physical properties of different commercially available silica optical fibers stepwise irradiated up to a total dose of 100 kGy. The detection of radiation-induced changes in silica glass offers the possibility of using selected optical fibers as distributed radiation sensors. The measurements performed by us were based on optical backscatter reflectometry and Brillouin distributed sensing. The measurement methods enable an analysis of radiation-induced modification of the group refractive index and density of the optical fibers. The most distinct physical effect observed by us concerns the increase of the optical attenuation with rising total radiation doses. Quantitative measurement results indicate a crucial impact of fiber dopants on radiation-induced physical and sensory characteristics of silica optical fibers affected by differences in fiber fabrication techniques. Based on the obtained results, the suitability of distributed Brillouin sensing for dosimetry applications seems to be improved by modifying the refractive index profile of the fiber core. T2 - Sixth European Workshop on Optical Fibre Sensors CY - Limerick, IRL DA - 31.05.2016 KW - Brillouin frequency shift KW - Lonizing radiation KW - Gamma radiation KW - Radiation dosimetry KW - Optical fiber sensor KW - Brillouin scattering KW - Distributed measurement KW - Backscatter reflectometry PY - 2016 SN - 978-1-5106-0219-9 DO - https://doi.org/10.1117/12.2236678 SN - 0277-786X VL - 9916 SP - Article Number: 99162J PB - Spie-Int Soc Optical Engineering CY - Bellingham, WA, USA AN - OPUS4-37083 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stajanca, Pavol A1 - Sporea, D. A1 - Mihai, L. A1 - Negut, D. A1 - Schukar, Marcus A1 - Krebber, Katerina ED - Bunge, C.-A. ED - Kruglov, R. T1 - Gamma radiation induced effects in perfluorinated polymer optical fibers for sensing applications N2 - Radiation induced attenuation in perfluorinated polymer optical fiber was investigated as a potential mean for online. in situ gamma radiation monitoring. Spectral dependence of radiation induced attenuation was measured in the visible and near infrared range. Attenuation spectrum exhibits sharp increase both towards the ultraviolet and infrared side of the spectrum with 3 distinct peaks around 1400 nm. The fiber sensitivity to gamma radiation was further evaluated at two commonly used IR wavelengths (1310nm and l550nm} by pre- and post-irradiation optical time-domain reflectometry measurements. The examined fiber is sensitive up to lOO kGy of total absorbed dose with only minor saturation towards the large dose values. The influence of gamma radiation on the fiber mechanical properties was studied as well. Up to the maximal dose of 100 kGy, no significant deterioration of fiber strength and elasticity was observed. T2 - 3rd International POF Modelling Workshop CY - Nuremberg, Germany DA - 21.09.2015 KW - Perfluorinated POF KW - Gamma radiation KW - Radiation induced losses KW - Radiation dosimetry PY - 2015 SN - 978-3739214993 SP - 95 EP - 103 PB - Books on Demand GmbH CY - Norderstedt AN - OPUS4-35287 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -