Dose Course Book

114-115 / 2239

Establishing a "transport formula"
Due to particle conservation, the number of particles within a
small volume element ∆V can be obtained from 4 processes:
j
dN = j,in-out
d N
−
j,att
dN
− j,secondaries
dN
+
j,source
d N
+
Note: The index j refers to a particular type of particle
j,in-out
d N
j,att
d N
−
j,secondaries
d N
+
j,source
d N
+
the net number of particles j flowing in and out of the
volume ∆V
the number of particles j that are attenuated in ∆V
the number of particles j that are born by
interactions with medium atoms in ∆V
the number of particles j produced by the sources
inside the volume ∆V
30