Since 1016 IFIC leads the design and construction of the temperature monitoring system for the DUNE far detectors, which rely on the largest cryostats ever built, with approximate inner dimensions 60x14x14 m3. Extraordinary know-how in temperature sensing in cryogenic environments has been developed with Resistance Temperature Detectors (RTDs), achieving a precision of few milikelvin.
Fiber Bragg Grating (FBG) constitutes an emerging technology, which have been well studied and used to monitor strain and temperature in engineering structures at ambient temperatures. However, insufficient R&D exists in cryogenic environments and the precision required for our application (< 0.005º) has not yet been achieved. IFIC is leading the R&D on this technology for its usage to monitor liquid argon temperatures in DUNE.