ESTRO course Dose Modelling and Verification 2017

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Radial differentiation of measured dose for (equivalent) circular fields
2 r
z
6 MV
   
meas 1
, ,
2
D p r z
r z
r dr   

CP Ceberg, et al (1996) Med Phys 23, 505-11.
Dashed line :MC
Solid line: from measurements
pencil kernel determination:
       
2
constant cylindrical Field 0 0
within geometry
field radius integrator
, , , , , d d , d d
r
p p
D x y z x y x x y y z x y r z r r

  
 
                 
 ,
p r z

Absolute normalization is a problem, can be circumvented by phantom scatter normalized measured
dose, and do renormalization via a reference field size of the calculated dose
since