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A simple method of producing depth ionization data for electron energy constancy check.

M K Islam·H Rashid·H Gaballa·J Ting·U F Rosenow
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Abstract

A simple method has been developed to reproduce depth ionization data of electron beams for energy determination. The method utilizes a simple set of equipment, a combination of a specially designed wedge-shaped polystyrene phantom and a linear array of detectors, to collect the necessary data. The wedge-shaped phantom provides varying depths to various detectors in the array. The ionization readings received from the detectors were corrected for off-axis ratio and plotted against corresponding ray-line depths to produce depth ionization curves. The instrument setup was fast and simple. The relevant data, for a high-energy linear accelerator with multiple electron energies, were collected in minutes. The depths of 80% and 50% ionization determined by this method were found to differ by 2 and 3 mm, respectively, at the most, with those determined by a conventional method.

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Biophysical PhenomenaBiophysicsElectronsEvaluation Studies as TopicHumansModels, StructuralQuality ControlRadiotherapy DosageRadiotherapy, High-EnergyJournal Article

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M K Islam, H Rashid, H Gaballa, J Ting, U F Rosenow. A simple method of producing depth ionization data for electron energy constancy check.. https://doi.org/10.1118/1.597083

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