Abstract
In this study, the characterization of parallel plate and the cylindrical ionization chamber which is used for calibration absorbed dose in water was investigated. The readings of 0.6 cc cylindrical ion chamber which is reference have been corrected by taking into account all influencing factors. The calibration factors of ionization chambers used in the measurement of electron was collected through reference ionization chamber with cross calibration. Factors derived were taken into account for the values of absorbed dose in water (Dw) for each electron energy and it’s sensitivity in measurements were investigated. Parallel plate and cylindrical ionization chamber dose measurements were the same precision above 12 MeV, while parallel plate ionization chamber is much more sensitive for the 6 and 9 MeV. Absorbed dose values obtained with cylindrical ionization chamber for 6 and 9 MeV showed deviation 2.9% and 2.5%, respectively. These results support that the necessity of the use parallel plate ionization chamber for the measurements of electron under 10 MeV mentioned in the Technical Reports Series (TRS)
Keywords
References
- International Atomic Energy Agency, “Absorbe dose determination in photonan delectron beams: An international code of practice”, Tecnical Reports Series No.277, Vienna, Austria, 1987.
- International Atomic EnergyAgency, “Theuse of plane paralel ionization chambers in high energy electron and photon beams: “Aninternational code of practice for dosimetry”, Tecnical Reports Series No.381 Vienna, Austria, 1997.
- International Atomic Energy Agency, “Absorbe dose determination in external beam radiotherapy: An international code of practice for dosimetry based on standards of absorbe dose towater” Tecnical Reports Series No.398 Vienna, Austria, 2000.
- I.H. Ferreira, D. Marre, M. SaifulHuq, A. Bridier, A. Beaudre, “Application of TRS 398 using ionization chambers calibrated by PSDLs in France and The United Kingdom in a series of high energy photon and electron beams” Proceedings of an International Symposium, Vienna, 2002.
Abstract
Bu çalışmada yüksek enerjili elektron demetleri için suda soğrulan doz kalibrasyonlarında kullanılan paralel plaka ve silindirik iyon odalarının karakteristikleri incelenmiştir. Referans olarak alınan 0,6cc silindirik iyon odasından elde edilen okumalar tüm etki faktörleri hesaba katılarak düzeltilmiştir. Elektron ölçümlerinde kullanılacak iyon odalarının kalibrasyon faktörleri referans iyon odası ile çapraz kalibrasyon işlemi yapılarak elde edilmiştir. Elde edilen faktörler her bir elektron enerjisi için suda soğrulan doz (Dw) değerlerinde hesaba katılmış ve verilmek istenen radyasyon dozu ölçümündeki duyarlılıkları incelenmiştir. Paralel plaka ve silindirik iyon odaları 12 MeV ve üzeri doz ölçümlerinde aynı hassasiyete sahipken, 6 ve 9 MeV enerjilerde paralel plaka iyon odası çok daha hassas davranmaktadır. 6 ve 9 MeV enerjilerde silindirik iyon odası ile elde edilen soğrulan doz değerleri sırasıyla %2,9 ve %2,5 oranında sapma göstermektedir. Bu sonuç Technical Reports Series (TRS) raporlarında belirtilen 10 MeV ve altındaki elektron ölçümlerinde paralel plaka iyon odasının kullanılması gerekliliğini desteklemektedir.
References
- International Atomic Energy Agency, “Absorbe dose determination in photonan delectron beams: An international code of practice”, Tecnical Reports Series No.277, Vienna, Austria, 1987.
- International Atomic EnergyAgency, “Theuse of plane paralel ionization chambers in high energy electron and photon beams: “Aninternational code of practice for dosimetry”, Tecnical Reports Series No.381 Vienna, Austria, 1997.
- International Atomic Energy Agency, “Absorbe dose determination in external beam radiotherapy: An international code of practice for dosimetry based on standards of absorbe dose towater” Tecnical Reports Series No.398 Vienna, Austria, 2000.
- I.H. Ferreira, D. Marre, M. SaifulHuq, A. Bridier, A. Beaudre, “Application of TRS 398 using ionization chambers calibrated by PSDLs in France and The United Kingdom in a series of high energy photon and electron beams” Proceedings of an International Symposium, Vienna, 2002.
Details
| Primary Language | Turkish |
|---|---|
| Journal Section | Research Article |
| Authors | |
| Publication Date | June 1, 2014 |
| Published in Issue | Year 2014 Volume: 2 Issue: 1 |