International Reactor Dosimetry File 2002 - IAEA Publications

(a)
(b)
(c)
(d)
The overall energy balance between the decay Q value and the sum of the
energies of all emitted particles (including recoils);
The sum of the transition intensities depopulating an excited level must
be equal to the feeding of this level;
The transition intensity between two excited levels has to be equal to the
sum of the gamma intensity and the converted electron intensities;
The total conversion coefficient must be close to the sum of the partial
coefficients for the different electron shells.
9.1.6. Results
The most intense radiations are presented and some explanations are
given in the header of the table on the CD-ROM (this information has the
same title as this section, and the data in the ENDF-B6 format are included on
the CD-ROM of IRDF-2002.
Nine radionuclides ( 95 Zr, 97 Zr, 103 Ru, 106 Ru, 116 In m , 131 I, 132 Te, 137 Cs and
144 Ce) have a decay branch leading to a daughter isomeric state. The total decay
intensity in this particular mode is given together with the fractions of the
decay that feed the ground and isomeric states.
For approximately 25% of the radionuclides considered, the main gamma
rays received special attention during the course of an IAEA coordinated
research project (CRP) [9.6]. Those readers who require a more extensive
evaluation of the nuclear decay data for radionuclides used as detector
efficiency calibration standards should consult the final document of this CRP:
Update of X-ray and Gamma-ray Decay Data Standards for Detector
Calibration and Other Applications.
9.2. ISOTOPIC ABUNDANCES
The proportion of nuclides affected by the neutron flux is directly related to
the isotopic composition of the elements. Thus these isotopic abundances are
very important quantities. Three major evaluations of isotopic composition have
been published over the previous ten years [9.7–9.9]. These three data references
give very similar values for the isotopic abundances of the 287 stable isotopes,
except for the following four isotopes, for which the deviations exceed 1%:
(a) Hydrogen-2 (3.04%);
(b) Xenon-124 (1.11%);
(c) Osmium-187 (–1.84%);
(d) Platinum-190 (–2.86%).
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