An organic dye in a polymer matrix – A search for a scintillator with long luminescent lifetime

Fiber-coupled organic plastic scintillators enable dose rate monitoring in conjunction with pulsed radiation sources like linear medical accelerators. The accelerator, however, generates a significant amount of stray ionizing radiation. This radiation excites the long optical fiber cable (15–20 m), connecting the scintillator with the optical detector circuit, causing parasitic luminescence in the optical fiber.

In this paper we propose a method for circumventing this problem. The method is based on the use of an organic scintillator with a long luminescent lifetime (room temperature phosphorescence). The long lifetime of the scintillator signal facilitates a temporal gating of the dose rate signal with respect to the parasitic luminescence from the optical fiber.