Korean J Med Phys.
2009 Dec;20(4):317-323.
The Study on the Use of a Cylindrical Ionization Chamber for the Calibration of a 6 MeV Electron Beam
- Affiliations
-
- 1Department of Radiation Oncology, College of Medicine, Hanyang University, Seoul, Korea.
- 2Department of Radiation Oncology, College of Medicine, Inha University, Korea.
- 3Department of Radiation Oncology, Gachon University Gil Hospital, Incheon, Korea.
- 4National Institute of Food and Drug Safety Evaluation, Korea.
- 5Department of Radiation Oncology, College of Medicine, Kyung Hee University, Seoul, Korea. ohsd32@naver.com
Abstract
- The standard dosimetry systems based on an absorbed dose to water recommend to use a planeparallel chamber for the calibration of such a low-megavoltage electron beam as a nominal energy of 6 MeV. For this energy ranges of an electron beam a cylindrical chamber should not be used for the routinely regular beam calibration, but the feasibility of the temporary use of a cylindrical chamber was studied to give temporary solutions for special situations users meet. The PTW30013 chambers and the electron beam quality of R(50)=2.25 g/cm2 were selected for this study. 10 PTW30013 chambers, a cylindrical type of chamber, were calibrated in KFDA, the secondary standards dosimetry laboratories, and given the absorbed dose-to-water calibration factors, respectively. A "temporary" kappa(Q,Q0) for each chamber were calculated using the absorbed dose determined by a cross-calibrated planeparallel chamber, with the result of an average 0.9352 for 10 chambers. This value for PTW30013 chamber was used to determine an absorbed dose to water at the reference depth. The absorbed doses determined by PTW30013 chambers were in an agreement within 2% with that by ROOS chamber. In a certain situation where a cylindrical chamber be used instead of a planeparellel chamber, the value of 0.9352 might be useful to determine an absorbed dose to water in the same beam quality of electron beam as this study.
Keyword
MeSH Terms
- Full Text Links
-
- Actions
-
Cited
- CITED
-
- Close
- Share
-
- Similar articles
-
- Study on Absorbed Dose Determination of Electron Beam Quality for Cross-calibration with Plane-parallel Ionization Chamber
- Chamber-to-chamber Variations in the Same Type of a Cylindrical Chamber for the Measurements of Absorbed Doses
- A Study on Electron Beam Dosimetry for Chest Wall Irradiation
- Determination of Beam Quality Correction Factors for the PTW-Markus Chamber for Electron Beam Qualities R50=1.0 and 1.4 g/cm2
- Chamber to Chamber Variations of a Cylindrical Ionization Chamber for the Calibration of an (192)Ir Brachytherapy Source Based on an Absorbed Dose to Water Standards
