Abstract
The major components in the x-ray photon beam path of the treatment head of the VARIAN Clinac 2300EX medical linear accelerator were modeled and simulated using the Monte CarloN-Particle radiation transport computer code (MCNP). Simulated components include x-ray target, primary conical collimator, x-ray beam flattening filter and secondary collimators. X-ray photon energy spectra and angular distributions were calculated using the model. The x-ray beam emerging from the secondary collimators were scored by considering the total x-ray spectra from the target as the source of x-rays at the target position. The depth dose distribution and dose profiles at different depths and field sizes have been calculated at a nominal operating potential of 6 MV and found to be within acceptable limits. It is concluded that accurate specification of the component dimensions, composition and nominal accelerating potential gives a good assessment of the x-ray energy spectra.
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Ajaj, F.A.A., Ghassal, N.M.H. An MCNP-based model of a medical linear accelerator x-ray photon beam. Australas. Phys. Eng. Sci. Med. 26, 140–144 (2003). https://doi.org/10.1007/BF03178784
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DOI: https://doi.org/10.1007/BF03178784