Advanced Physics for Brachytherapy 2018

Type B uncertainty … input ➢ Phantom geometry (for single source dosimetry) Remember dose from scatter depends on geometry dimensions…! or patient segmentation and source/applicator position (for patient dosimetry)

➢ Geometry in simulation for S K

(for single source dosimetry)

In order to comply with the definition of S K :

• Air (point) detector at large distance from the source in vacuo • Photon emissions of energy lower than δ=5 keV (i.e. characteristic x-rays of Ti encapsulation following photoelectric absorption of 125I photons) must be suppressed.