Dose 2016
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
Utrecht 2016
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