Dose 2016

Establishing a "transport formula"

Due to particle conservation, the number of particles within a small volume element ∆ V can be obtained from 4 processes:

d N d N + Note: The index j refers to a particular type of particle − d N − d N +

d N

=

j,in-out

j,secondaries

j,source

j

j,att

the net number of particles j flowing in and out of the volume ∆ V

d N

j,in-out

d N −

the number of particles j that are attenuated in ∆ V

j,att

the number of particles j that are born by interactions with medium atoms in ∆ V

d N +

j,secondaries

d N +

the number of particles j produced by the sources inside the volume ∆ V

j,source

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