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Use of solid plastic materials for dosimetry
Determination of absorbed dose to water using an ionisation chamber in a solid plastic
phantom:
The dosimetry formalism that converts ionisation measured in a solid plastic to dose in
water necessitates that the density and composition of the material are known, as well as
• Appropriate detector perturbation factors (not widely available)
• Phantom conversion factor can be determined experimentally
•
Epoxy resin based solid phantoms
shown to be equivalent to within 1% to water
Relevant references:
Jan Seuntjens etal, 2005, Med.Phys. 32 pp2945-
Araki etal, 2009, Med.Phys. 36 (7) pp2992-
McEwen, Med Phys 33(4), 2006, p876-
Fujita, Y. et al (2010). J Radiat Res
51
(6): 707-713.
Formalism in Dosimetry Code of Practice
for dose to water from a measurement in plastic
D
w
,
Q
z
ref
(
)
=
M
s
,
Q
z
eq
(
)
N
D,w,Q
o
k
Q,Q
o
k
w
,
s
Q
from dose to water formalism