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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 ∆r2 Under the collapsed cone approximation:
• Scerma does not vary with θ within ΔΩ
1
2
θ
(Bθ, bθ constant along transport line)
and scerma generated, emitted and
absorbed along transport line
and assuming:
• Scerma generated per unit r is constant
Averaging scerma from voxel 2, over points
ithi Δ 2 i l 2
within the same voxel (scerma does not
vary considerably within voxels)
2Δr
)] exp( 1[
1sc,2 S
2Δr
2 21scD 

 dr rb
b
B
dr      
w n r n voxe :
)}2Δr exp( 1[ 2Δr {
1 2 S
2Δr
0
2Δr
0
2 21scD
   b b B  

  
2Δr 2 sc,
 b