Physics Athens 2016

Dose Deposition Kernel High Energy

 High energy : electron track lengths are of the same order as the photon mean free paths

 Large primary dose region (long BU distance & broad penumbra)

 Narrow scatter dose region (low dose outside field)

 Forward directed isolevels (small amount of backscatter)

From: A. Ahnesjö and M.M. Aspradakis, Dose calculations for external photon beams in radiotherapy. Phys Med Biol 44 (1999), pp. R99–R155.