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Particles – Mean Energy
Example:
β
-
decay of
137
Cs Photons
The emission weighted mean energy E
mean
is defined as:
Characteristic
keV 4. 615
f
Ef
E
i
i
i
i
mean
=
⋅
=
∑
∑
γ
-rays
E
i
f
i
i
f
i
is the intensity (or emission frequency)
of the specific energy line E
i
and the sum
is taken over all photon ray energies E
i
of
the radionuclide spectrum.