International Reactor Dosimetry File 2002 - IAEA Publications

Appendix III
COMPARISON OF THERMAL CROSS-SECTIONS AND RESONANCE
INTEGRALS FOR DOSIMETRY REACTIONS
A. Trkov
IRDF-2002 contains cross-sections for 66 reactions, of which 17 represent
radiative capture. Verification and validation of the cross-section data from
various sources are important steps in the selection of the source data and for
validation of the final dosimetry library. Therefore, a comparison of the
evaluated data from different sources was made using the following:
(a)
(b)
Mughabghab evaluation of the thermal cross-sections and resonance
integrals [III.1];
Q 0 values, which are the ratios of the resonance integral to thermal crosssection
from the k 0 database for neutron activation analysis (NAA) [III.2].
The Mughabghab compilation, commonly known as BNL-325, is the most
comprehensive compilation of thermal cross-sections and resonance integrals
and has been recently revised by the author.
Activation analysis is in some sense ‘reverse dosimetry’. Well tested and
applied in practice, the nuclear data for activation analysis are highly relevant
to a dosimetry database. The k 0 standardization method is a variant of
activation analysis, and requires the Q 0 value for each nuclide. The Q 0 values
for several nuclides have been measured, usually by the cadmium ratio method,
which is insensitive to the detector efficiency and the abundance of the nuclide
in a natural mixture of an element.
The following evaluated nuclear data libraries were considered in the
present study:
(i)
(ii)
(iii)
(iv)
(v)
(vi)
The old IRDF-90.2 dosimetry library [III.3];
The JENDL-D/99 dosimetry library [III.4];
The latest Japanese JENDL-3.3 evaluated nuclear data library [III.5];
US library ENDF/B-VI Release 8 [III.6];
European Activation File EAF-99 [III.7];
The new evaluations for 139 La and 186 W by Zolotarev [III.8].
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