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PubMed · 16797095

Notes on the construction of solid-state detectors.

Carolyn McKerracher·David I Thwaites
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Abstract

BACKGROUND AND PURPOSE: Solid-state detectors such as diodes and diamonds are useful radiation detectors, particularly for small field measurements, such as in stereotactic dosimetry or in the small sub-field measurements required for intensity modulated radiotherapy (IMRT) . In all small field measurements, positioning of the detector is critical. Generally it is assumed that the center of the sensitive volume of each solid-state detector is coincident with the geometric center of the outer casing. PATIENTS AND METHODS: X-rays were taken of four detectors (diamond, three types of diode) to determine the physical characteristics of each, particularly the position of the centre of the sensitive volume. RESULTS: The results showed that the position of the centre of the sensitive volume is not always coincident with the geometric centre of a solid-state detector. CONCLUSIONS: The construction of a detector used for precise measurements should be investigated prior to use, by taking high resolution x-ray images.

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Carolyn McKerracher, David I Thwaites. 2006-06-22. Notes on the construction of solid-state detectors.. https://doi.org/10.1016/j.radonc.2006.05.008

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