Neutron Cross Section - Continuous Versus Average Cross Section

Continuous Versus Average Cross Section

Cross sections depend strongly on the incoming particle speed. In the case of a beam with multiple particle speeds, the reaction rate R is integrated over the whole range of energy:

Where σ(E) is the continuous cross section, Φ(E) the differential flux and N the target atom density.

In order to obtain a formulation equivalent to the mono energetic case, an average cross section is defined:

Where Φ= Φ(E) dE is the integral flux.

Using the definition of the integral flux Φ and the average cross section σ, the same formulation as before is found:

Read more about this topic:  Neutron Cross Section

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