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An equivalent square method for irregular photon fields.

A F Monti·A Ostinelli·M Frigerio·S Gelosa
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Abstract

A quick formula is proposed for calculating equivalent squares of irregularly shaped photon fields. No complex calculations are required. Three different energies (60Co; 6 MV and 18 MV x-rays) were investigated. Comparison with results utilizing the Clarkson technique (60Co) and with experimental measurements (6 MV and 18 MV x-rays) indicates that the method is accettable in a wide variety of clinical situations. The applied procedure introduces an indetermination lower than 4%, with maximum absolute percentage errors of 3%, 2.7%, and 3.6% for 6 MV, 18 MV, and 60Co photon fields respectively.

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BibTeXRIS

A F Monti, A Ostinelli, M Frigerio, S Gelosa. 1995. An equivalent square method for irregular photon fields.. https://doi.org/10.1016/0958-3947(95)02005-5

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