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Equations for the transport of scerma
1. I need to be efficient
∆r
generated at each point along a
transport line
1
θ
Under the collapsed cone approximation:
•
Scerma does not vary with θ within ΔΩ
1
2
(Bθ, bθ constant along transport line)
and scerma generated, emitted and
absorbed along transport line
r
and assuming:
•
Scerma generated per unit r is constant
Dose
from
points along Δr1 in voxel 1,
to
voxel 2 :
within the same voxel (scerma does not
vary considerably within voxels)
)
exp(
1sc,1 S
ρ2
ρ1
211scD
dr d
r
rb
B
1
dr )'
exp(
1sc,1 S
ρ2
ρ1
r r
r
rb
B
)]1
exp(
1)[
exp(
1sc,1 S
ρ2
ρ1
r b
rb
b
B