An automated procedure for the quality assurance of electron beam output and energy

In this article, we report on the development of a simple and accurate method for quality assurance of electron beam output and energy. Aluminum disks of thicknesses dmax or d50 of the particular electron energy are positioned sequentially over a parallel-plate ion chamber and the ratio of the two signals is compared to the standard. The positioning of the aluminum disks is carried out remotely and automatically to eliminate the necessity of multiple setups. One method utilizes the remote control feature of the treatment couch and another employs a motor-driven carousel. The superior sensitivity over a commercially available energy monitor is illustrated