ESTRO course Dose Modelling and Verification 2017

30

Dose monitor chamber

Transmission ionization chamber that monitors and controls delivered dose (MU), dose rate, beam symmetry and flatness.

Varian

The dosimetry system must contain two independent channels. Sealed or open compensated chambers  no dosimetric influence from ambient air pressure or temperature. The E-field (bias voltage) should be high (  500 V/mm) in order to minimize recombination/dose rate dependence. Commonly layered through thin and strong foils with condensed Au or Cu. Total thickness  0.2 mm.

Elekta

T Knöös

Warsaw 2017