Dosimetry Mapping of Mixed-Field Radiation Environment Through Combined Distributed Optical Fiber Sensing and FLUKA Simulation

Distributed optical fiber (OF) radiation sensing is a technique recently adopted at CERN for the monitoring of radiation dose levels in the proton synchrotron (PS) booster and in the PS. In this paper, we present the progress made on our previous work by benchmarking the rich information contained in the spatially distributed OF dose measurement with the radiation levels simulated with the FLUKA Monte Carlo code. We begin by discussing the experimental results for the qualification/calibration of a new radiation sensitive single-mode OF, currently being deployed in the accelerator tunnels. We performed this calibration tests online under$^{60}$Co $\gamma$-rays source. We then move on to report the results of the online irradiation tests that we carried out in the CERN high energy accelerator mixed-field facility. Finally, we compare the OF radiation maps with the dose levels calculated along the OF cable with FLUKA for two very different configurations of the facility. This paper is a first promising example of combining 3-D Monte Carlo simulations of complex mixed-field environment with the 1-D spatially distributed dose measurements provided by the OF-based dosimetry.