1300-1301 / 2239
IAEA/AAPM formalism for reference dosimetry
composite MV photon fields
pcsr
Q
beam quality for the pcsr field
msr
pcsr
msr
pcsr
ref
msr
msr
o
o
pcsr
pcsr
pcsr
pcsr
f
f
Q Q
f
f
QQ QQ QwD
f
Q
f
Qw
k
k k
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ref
pcsr
pcsr
f
f
Q Q
k
,
,
pcsr
f
represents a class of dynamic or step-and-shoot delivery fields,
or a combination of fields,
such that full CPE is achieved in a time
average sense at the position of the detector
For example, AAPM TG148 recommends:
A field that delivers a uniform 2Gy to a cylinder of 8cm diameter
and 10cm length, placed along the axis of a Virtual Water
Cclindrical phantom, using 5cm slice thickness and 0.287
pitch and 1.807 modulation factor