عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Electron beams are widely used in radiation therapy. Since the nominal electron energy value is not quite meaningful for physics or dosimetry purposes in treatment planning, depth dose data for electron beams must be determined and used. The purpose of this study was to obtain the depth dose data for the 6 and 8 MeV electron beams of a NEPTUN 10PC linac and evaluating its beam characteristics using Monte Carlo method. The linac electron beams were modeled using the BEAMnrc code. The DOSXYZnrc code was also used for the simulation of RFA 300 water phantom. The central axis depth dose and the beam profiles were calculated for the beam energies at the 10×10 cm2 field size. The R100, Rq, R85, R50 and Rp parameters were extracted from the normalized depth-dose curves. The calculated results were compared with the experimental data, where the agreement between them was very good. Since different linacs from the same manufacturer and model usually have the same structures, it seems that it can be possible to model different linacs based on a particular one from the same manufacturer by defining their energy spectra and the beam quality indexes. In addition, using this method enables us to assess the characteristics of the electron beam at the exit of the linac and the effects of every part of the linacs head structure on the electron beams. It may also be possible to study and evaluate the final dose distribution.
18. American Association of Physicists in Medicine (AAPM) Task Group 25 ,“Clinical electron-beam dosimetry,” Med. Phys. 18, 73-109 (1991).