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External Audit: Beam calibration
• Q1= beam quality of the reference Linac
• Q2= beam quality Linac-like condition cyberknife
D= M* x Nd,w x Kq,q
0
• Approximation of kq,q
0
=1 When kq,q
0
=
0,996
(A quantity kQ, the beam quality correction factor, is defined which corrects the absorbed
dose-to-water calibration factor ND,w in a reference beam of quality Q0 to that in a user's
beam of quality Q1)
Systematic error of 0,4%
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