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1. I need to be efficient
Δr
1
1
2
ρ1
D
S
exp(
)
1sc1 2
1sc,1
ρ2
1
ρ1
S
exp(
') dr
1sc,1
ρ2
ρ1
S
exp(
)[1 exp(
)]
1sc,1
1
ρ2
B
b r d dr
r
r r
B
b r
r
B
b r
b r
b
=
−
=
→
+
−
=
−
− −
θ
Dose
from
points along Δr1 in voxel 1,
to
a point
in voxel 2 :
Equations for the transport of scerma
generated at each point along a
transport line
Under the collapsed cone approximation:
•
Scerma does not vary with θ within ΔΩ
(Bθ, bθ constant along transport line)
and scerma generated, emitted and
absorbed along transport line
and assuming:
•
Scerma generated per unit r is constant
within the same voxel (scerma does not
vary considerably within voxels)
r'
r
S ρ
1sc,1 1 exp(
)[1 exp(
)]
1
ρ 2
B
b r
b r
b
=
−
−
−
Mass energy absorption term [cm
2
/g]
Ψ
1sc
term [J/cm
2
]
Attenuation term