Hydrogen and radiation induced effects on performances of Raman fiber-based temperature sensors

Raman Distributed Temperature Sensors (RDTS) offer exceptional advantages for the monitoring of the envisioned Frenchdeep geological repository for nuclear wastes, called Cigéo. Here, we present experimental studies on how the performances of RDTS evolve in harsh environments like those associated with H2 or g-rays. Both of them are shown to strongly affect the temperature measurements made with RDTS. We showed that by adapting the characteristics of the used fiber for the sensing, we could limit its degradation but that additional hardening by system studies will have to be developed beforeintegration of RDTS in Cigéo.