International Reactor Dosimetry File 2002 - IAEA Publications

Diff. number spectrum, F(E)
Neutron energy (MeV)
FIG. 7.6. F(E)E representation of calculated spectrum.
due to neutron backscattering from the walls of the kiva into the reactor
experiment cavity (centre of the core). A more extensive description of this
reference field appeared in Ref. [7.5], while details of the radiation transport
models and 640 group representation of the neutron spectrum in the central
cavity can be found in Ref. [7.10].
Figure 7.6 shows the SAND-II unfolded neutron spectrum in a typical
logarithmic fluence plot (written as Φ(E) or dn/dE). The calculated spectrum in a
linear lethargy plot (written as EΦ(E), but often written as Φ(μ) or dE/dE) is
shown in Fig. 7.7; equal areas under the curve correspond to equal neutron content
in the lethargy plot (with linear y axis and logarithmic energy x axis or lethargy).
Diff. energy fluence, EF(E)
Neutron energy (MeV)
FIG. 7.7. EF(E) representation of calculated spectrum.
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