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Abstract: The present paper deals with the accuracy and applicability of the k0-standardization technique in NAA. Topics included are: user-oriented outline of the method, relevant nuclear data (k0, Q0, ecarontc.), the non-1/E epithermal flux distribution, small detector separations and/or extended source geometries, (n, gamma) reactions with a Westcott-gne1, primary interferences, subsequent (interrupted) irradiations, the non-constancy of the neutron flux during irradiation, and a final account of the accuracy. Although the paper is written in terms of the k0-methodology, a good deal of the considerations can be transferred to most types of single-comparator standardization.

Abstract: The concept of the effective resonance energy $$\bar E_r $$ , formerly introduced as a parameter in the absolute (e.g. k0-) standardization methodology of (n, gamma) activation analysis, is elucidated with respect to dimensioning, accuracy and usefulness.

Abstract: Recommended k0-factors and related nuclear data for use in (n, gamma) activation analysis are given for 72 isotopes. In addition the basic nuclear constants and experimental parameters needed in the k0 standardization method are reviewed. For convenient data reduction, computer programs were developed.

Abstract: The effective resonance energy $$\left( {\bar E_r } \right)$$ , a useful parameter when correcting the resonance integral for a non-ideal epithermal neutron flux distribution, can be experimentally determined by coirradiating the investigated isotope with a comparator isotope whose effective resonance energy is accurately known. The principle of the method is outlined and the error propagation functions are studies in detail. The usefulness of the $$\bar E_r $$ -comparatorrdquo technique is tested for a few isotopes.

Abstract: A ldquobestrdquo choice from literature was made of the isotopic abundance values for64zn,112Sn and174Yb, and of the absolute gamma-intensities for65Zn,113mIn and175Yb. From these data and from ldquoactivation methodrdquo experiments, the following 2200 m·s–1 cross sections were determined:65Zn(n, gamma)65Zn; sgr0=(0.726±0.0007) barn [cf. literature 0.76–0.78 barn];112Sn(n,gamma)113(m)Sn; sgr0(0.91 m+g)=(0.539±0.011) barn [cf. literature sim1 barn];174Yb(n,gamma)175(m)Yb; sgr0(m+g)=(130+4) barn [cf. literature 65 barn].

Abstract: The116Sn (n, γ)117mSn reaction commonly used in reactor-neutron activation analysis (RNAA) turned out to be seriously interfered by the117Sn (n, n′)117mSn reaction, as observed from irradiation in channels with largely different neutron thermalization. To estimate the magnitude of this primary interference an attempt was made to determine the relevant fission neutron averaged cross-section, yielding approximately σn, n, (117Sn)==0.09±0.01 barn. This value—believed to be the first measured and published—is remarkably high especially when compared to the 2200 m·s−1 cross-section σo[116Sn(n, γ)117mSn]=0.006 barn.