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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
∆r2 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
θ
and assuming:
• Scerma generated per unit r is constant
Overall, exiting voxel 2:
within the same voxel (scerma does not
vary considerably within voxels)
2 21scD211scD21scD  
2Δr
)}2Δr exp( 1[ 2Δr {
2 1sc,2 S )]2 exp( 1[
2Δr2ρ
1 )
exp( )]1 exp( 1[2
1sc,1 S1ρ  


  

 b b
b
B
r b rb r b
b
B  
        