In-situ detector theoretical design for low-activity concentration tritiated water based on plastic scintillator thin film flow cell

In order to ensure radiation safety and control the potential risk of tritium, the in-situ measurement technology of low radioactive concentration tritiated water has wide practical demands.A novel detector was theoretically designed utilizing plastic scintillator thin films (PSTFs) and silicon photomultiplier arrays (SiPMs) to achieve this objective. Key parameters such as sample chamber thickness, plastic scintillator thickness, and the number of sample chambers were analyzed using Monte Carlo simulations, thoroughly evaluating factors influencing energy deposition, optical transmission, detection efficiency, and minimum detectable activity concentration (MDAC). The results demonstrated that the system achieved a detection efficiency of 22.5% with the MDAC of 6.909 Bq/mL for tritiated water over a counting time of one minute. This compact and highly sensitive detector configuration is well-suited for a range of applications in environmental monitoring and radiation safety.