Potential on liquid light guide as distributed radiation sensor

Position sensitive detectors with optical fibers are useful for one-dimensional distributed radiation sensing. There has been, however, a problem of radiation induced transmission losses and life time of the optical fibers restricting their applicability for high-level radiation environments. In order to improve the limitation of the optical fiber based radiation sensing, we propose to use a liquid light guide (LLG) with more radiation hardness than the solid one. The preliminary experiments have given us some promising results that the incident radiation emits the Cherenkov photons in the core and the position can be determined by the time-of-flight method. At present, we have confirmed that the position resolution is around 9.6 cm in a 2 m long LLG for the ⁶⁰Co gamma-ray beam with a diameter of 10 mm and no transmission loss is observed up to the dose of 2.5×10³ Gy.