Dose 2016

5.2 Establishing a "transport formula"

(2) The number of particles j that are attenuated in ∆ V:

Introducing as the probability per unit path length for particle j of energy E and direction Ω to attenuate, we have: , j att σ VL dd =Φ

d

L

V ⋅Φ= d

∫

d

N

L dd

σ=

Ω⋅

j,att

j,att

dv

∫ σ

d d d

E V

=

⋅ Φ Ω

, j att

j

d

V

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