The influence of air cavities on the dose distribution of high-energy electron beams.
A Lucite phantom containing cylindrical air cavities was irradiated with high-energy electrons from a betatron. By measuring depth-dose curves, the relative enhancement in electron fluence adjacent to the cavity on the side opposite to the beam entrance was determined as a function of the initial electron energy, the dimensions of the cavity and its depth in the phantom. The enhancement factor was found to be critically dependent on energy, the height of the cavity and its depth in the phantom, but to a lesser extent on its diameter. The experimental results have been compared with calculations based on multiple scattering theory.
D000388:Air; D004583:Electrons; D011879:Radiotherapy Dosage; D011882:Radiotherapy, High-Energy; D012542:Scattering, Radiation