Energy response of an imaging plate exposed to standard beta sources

Department of Radiation Oncology, Vanderbilt University, The Vanderbilt Clinic, B-902, 1301 22nd Avenue South, Nashville, TN 37232-5671, USA.
Applied Radiation and Isotopes (Impact Factor: 1.23). 01/2003; 57(6):875-82. DOI: 10.1016/S0969-8043(02)00199-9
Source: PubMed


Imaging plates (IPs) are a reusable media, which when exposed to ionizing radiation, store a latent image that can be read out with a red laser as photostimulated luminescence (PSL). They are widely used as a substitute for X-ray films for diagnostic studies. In diagnostic radiology this technology is known as computed radiography. In this work, the energy response of a commercial IP to beta-particle reference radiation fields used for calibrations at the National Institute of Standards and Technology was investigated. The absorbed dose in the active storage phosphor layer was calculated following the scaling procedure for depth dose for high Z materials with reference to water. It was found that the beta particles from Pm-147 and Kr-85 gave 68% and 24% higher PSL responses than that induced by Sr-90, respectively, which was caused by the different PSL detection efficiencies. In addition, normalized response curves of the IPs as a function of depth in polystyrene were measured and compared with the data measured using extrapolation chamber techniques. The difference between both sets of data resulted from the continuous energy change as the beta particle travels across the material, which leads to a different PSL response.

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Available from: Dennis Duggan, Oct 21, 2014
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    • "PSPs were also found to be a useful tool for measuring doses from beta sources. The response to 147Pm beta rays was found to be higher than to 90Sr and 85Kr beta rays by 68% and 35% respectively.[53] The utility of these dosimeters has now been extended[54] to cover neutron fields by sandwiching a PSP between polythene plates for using recoil protons and between nylon plates for using the 14N(n,p)14C reaction for detection of neutrons. "
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