الفهرس 
Introductionand aim of the workOnly 14 pages are availabe for public view
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Abstract
The purpose of this study is achieving the Total Skin Electron Therapy TSET (Stanford Technique) by measuring and verifying the Beam flatness dual fields and six dual fields, the regional dose distribution over treatment plane with 6 beam pairs, effective depth dose for multiple fields, energy variation, Xray contamination, and absolute dose for dual and six dual fields for highenergy linear accelerator (Philips SL15) by using energies 4, 6, 8 and 10 MeV. The percentage depth dose (PDD) of energies under study are measured at SSD = 400 cm with and without beam scatterer, 6 mm thickness perspex beam scatterer is used for energies 4 and 6 MeV, and 10 mm perspex beam scatterer is used for energies 8 and 10 MeV. There is shift of the depth of maximum dose and the rapid dose falloff region towards greater depth. There were a noticeable decrease in most probable energy Ep, 0 from 4 to 3.39 MeV, 6 to 4.89 MeV, 8 to 6.78 MeV and 10 to 8.58 MeV at SSD = 400 cm. There are decreasing in values of all PDD parameters for all energies. Energy loses totaling about from 2.25 MeV for 4 MeV to 4.6 MeV for 10 MeV occur between the exit window of the accelerator and the treatment plane. The optimum gantry tilt was (R+(B14o for energies 4 MeV and 6 MeV, and (R+(B15o for energies 8 MeV and 10 MeV that having good uniformity at beam angle. The Xray contamination was measured in a single dual beam which is 1.95%, while, the resulting total body photon dose is ~ 3.9% of the prescribed electron dose or 1.56 Gy for a typical prescribed electron dose 40 Gy. The absorbed dose was measured at SSD = 400 cm for single, dual and six dual fields by applying AAPM and IAEA dosimetry protocols.