Absolute calibration for film dosimetry

Abstract

Recent results in the field of film dosimetry demonstrated that the Green–Saunders equation, a solution of the logistic equation describing phenomena of kinetics of chemical reactions, is the absolute calibration function for all radiochromic film types. Taking advantage of the new opto-electronics-based radiochromic film reading method, which allows real-time measurements of the spectral response of radiochromic films, we confirm that the film darkening is ruled by the Green–Saunders equation independently both from the reading instrument or the choice of the observable used for the calibration. In order to demonstrate it, we exposed an XR-QA2 Gafchromic film to 90Sr/90Y beta rays up to 1400 mGy. Film spectra are recorded in real-time. The calibration is performed by means of two analytic methods: evaluation of the integral under the curves from 500 nm to 645 nm and evaluation of the intensity at 570, 600 and 643 nm. Experimental data fit to the Green–Saunders equation for both methods.

Innovative Photonic Sensors for Safety and Security, Part III: Environment, Agriculture and Soil Monitoring

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An Innovative Real-Time Dosimeter for Radiation Hardness Assurance Tests

“…In this paper, an innovative dosimeter for real-time dose monitoring in RHA tests is proposed. It is based on a new radiochromic film (RCF) spectroscopic reading method that was recently developed [7][8][9][10][11][12][13][14][15]. This new dosimeter allows for correlating in real-time the radiation dose at which the device is exposed to with the device performance.…”