192Ir is one of the most popular radiation sources used for brachytherapy treatments. However, 192Ir emits a wide photon spectrum (10 keV to 900 keV) which impedes the creation of an 192Ir primary standard. The 192Ir air kerma calibration factor is derived by interpolating between 60Co, 137Cs and hard orthovoltage air kerma calibration factors obtained from a standards laboratory. The EGSnrc Monte Carlo package was used to calculate the response in low energy photon beams of a commercial parallel-plate chamber to assess useability as a 192Ir and kilovoltage photon beam calibration tool. XCOM photoeffect cross-sections were implemented in EGSnrc to improve kerma calculation agreement at low energies. The response calculations were compared to experimental data from PTB (Germany). Overall, agreement between calculations and measurement is good and represents an improvement to results from the literature. However, discrepancies exist at the lowest energies which may be caused by differences in the measurement and calculation geometries.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.78378 |
| Date | January 2003 |
| Creators | Hobeila, Fadi |
| Contributors | Seuntjens, Jan P. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Medical Radiation Physics.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001976403, proquestno: AAIMQ88213, Theses scanned by UMI/ProQuest. |
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