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Abstract

In present study, water phantom performances of using 6 and 18 MV photon beams were investigated. For this purpose, several data obtained form percent depth dose graphics and dose profiles were compared to each other. It was determined that the differences between the values were generally found within the limits. In the end of study, it was seen that semiconductor diodes and cylindrical ion chambers can be used interchangeably. But, there are some dozimetric differences between both detectors because of different detector structures. Choice of the detector can be made by taking into account these differences

Keywords

• Diode, ion chamber, radiotherapy, dosimetry

Radyoterapi Işınlarının Kalite Kontrolünde Yarı İletken Diyot ve Silindirik İyon Odası Performanslarının Karşılaştırılması

Abstract

Bu çalışmada; 6 ve 18 MV foton ışınları kullanılarak yarı iletken diyotlar ve silindirik iyon odalarının su fantomunu performansları incelenmiştir. Bu amaçla, yüzde derin doz ve doz profillerinden elde edilen çeşitli veriler bir birleri ile karşılaştırıldı. De_erler arasındaki farklar genel olarak limitler içinde tespit edilmiştir. Çalışmanın sonucunda diyot ve iyon odası tipindeki detektörlerin her ikisinin de su fantomu ile yapılan rutin ölçümlerde kullanılabileceği görülmüştür. Fakat detektör yapılarının tamamen farklı oluşu sebebiyle aralarında bazı dozimetrik farklar mevcuttur. Bu farklar gözetilerek detektör kullanımları arasında tercih yapılabilir. Anahtar kelimeler: Diyot, iyon odası, radyoterapi, dozimetri A Comparison for the Performances of Semiconductor Diodes and Cylindrical Ion Chambers in the Quality Control of Radiotherapy Beams Abstract: In present study, water phantom performances of using 6 and 18 MV photon beams were investigated. For this purpose, several data obtained form percent depth dose graphics and dose profiles were compared to each other. It was determined that the differences between the values were generally found within the limits. In the end of study, it was seen that semiconductor diodes and cylindrical ion chambers can be used interchangeably. But, there are some dozimetric differences between both detectors because of different detector structures. Choice of the detector can be made by taking into account these differences. Key words: Diode, ion chamber, radiotherapy, dosimetry

Keywords

• Diyot, iyon odası, radyoterapi, dozimetri

References

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12. Serkan Okay e-posta: [e-mail]
13. Bayram Demir e-posta: [e-mail]
14. Asuman Öztaş e-posta: [e-mail]