TY - BOOK AU - Soad Mostafa Mohammed Hozayen AU - Hassan Fathy Ibrahim , AU - Hoda Aboushady , TI - Design and modeling of medical linear accelerators using the geant 4/GATE platform / PY - 2018/// CY - Cairo : PB - Soad Mostafa Mohammed Hozayen , KW - Linear accelerator KW - Photon and electron mode KW - Radiotherapy N1 - Thesis (M.Sc.) - Cairo University - Faculty of Science - Department of Physics; Issued also as CD N2 - The aim of this research is to investigate the use of GATE, the monte Carlo simulation application based on Geant 4 toolkit to estimate the percent depth doses and dose Off-Axis Ratios of a novel medical linear accelerator for photon mode field sizes 5{u00D7}5, 10{u00D7}10, 20{u00D7}20, 30{u00D7}30 and 40{u00D7}40 cm² and also for electron mode field sizes 5{u00D7}5, 10{u00D7}10, 15{u00D7}15 and 20{u00D7}20 cm² at the isocenter. A model for the 60{u00D7}50{u00D7}40.75 cm³ PTW MP3 water phantom was used in the simulations. Firstly, verification of the dose calculations of two medical linacs: Siemens ONCOR for field sizes 10{u00D7}10, 20{u00D7}20 and 30{u00D7}30 cm² and varian 600C for field sizes 3{u00D7}3, 6{u00D7}6 and 9.8{u00D7}9.8 cm² using 6 MeV electron beam, were confirmed ER -