(
)
(
)
M
zy
xAD
M
zyxAD
o
o
, , ;
, , ;
=
relates the MU to the incident direct
energy fluence under
reference
calibration conditions
(
)
(
)
calc
ref
ref
ref
ref
meas
ref
ref
ref
ref
o
,
,
;
,
,
;
o
z
y x
AD
M
z y x A
D
M
=
Energy fluence of
direct photons
at isocentre in air
M
D
meas
ref,
o
calc ref,
D
Calibration factor
Dose per MU formalisms:
model-based dose calculations