Course book Advanced Treatment Planning 2018

X-Rays: Energy Deposition in a Nutshell

X rays do ionize indirectly.

On interaction, energy is

scattered or transferred to electrons, then absorbed. Biological effect depends on the amount of energy absorbed ( dose ). Tracking electrons is highly important for accurate dose calculations. One treatment (2 Gy) requires ~10 8-9 incident x rays per mm 2 .