Pulsed X‐Ray Radiation Responses of Solarization‐Resistant Optical Fibers

The transient radiation-induced attenuation (RIA) of two different versionsof pure-silica-core (PSC) multimode optical fibers (so-called“solarization-resistant”fibers) exposed to nanosecond 1 MeV X-ray pulses are investigated.On-line RIA spectra measurements at both room temperature (RT) and liquidnitrogen temperatures (LNT) in the range 1–3.5 eV are performed. Followingthe RIA kinetics, the properties of the metastable defects that are bleachedjust after the pulse are discussed. The spectral decomposition of the RIA isperformed using known Gaussian bands associated to point defects absorb-ing in this spectral range. For both fiber types, the generation and the post-irradiation kinetics of the self-trapped holes (STHs) that are the maincontributor to the transient RIA are investigated particularly. Moreover, thanksto the measurements performed at low temperatures the complex tempera-ture dependence of the kinetics of self-trapped holes and some chlorine-related species is characterized.