Figure 6
From: Functional intercomparison of intraoperative radiotherapy equipment – Photon Radiosurgery System
Depth Dose Comparison. Depth-dose curves were obtained by measuring the chamber output at distances of between 12 and 35 mm away from the probe tip in water. The ionisation chamber was placed as close as possible to the outer surface of the water phantom to minimise the effect of air gaps. It was found that beam attenuation varies by approximately 1/r3as previously reported [14, 20].