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This work is devoted to an evaluation of the integral coefficients of neutron resonances directly from resonance parameters, which enables the evaluation of individually distinct single-resonance integrals. Individually distinct single-resonance integrals are useful when investigating the statistical nature of resonance distribution, the role of the neutron flux shape parameter, applications in nuclear reaction physics, isotope synthesis in reactors and astrophysical entities, activation analysis, and the science of nuclear materials. The present R-matrix treatment comprises exact expressions for the Breit-Wigner resonance representation and approximate expressions for the Reich-Moore representation; the latter is used to avoid the complicated techniques used for matrix inversion. The analytical formulae are used to evaluate the necessary integral neutron coefficients directly from spectroscopic nuclear data. Using the analytical formulae, the resonance integrals and the effective resonance energy can be taken into consideration for any specific values of epi-thermal shape parameter. In addition, the atomic displacement densities can be computed with variable threshold energies for atomic displacements. A Fortran code, NEURESINT, designed to perform these calculations is given in the manuscript's supplementary material available online at stacks.iop.org/PS/94/065301/mmedia. The code is used to compare integral coefficients among different versions of evaluated nuclear data files. The present approximation gives thoroughly consistent results with the reported values of integral parameters. Our results showed that care must be taken when applying the methods and code mentioned in the present work to some isotopes, especially actinides having a resonance level close to the epi-cadmium cutoff energy at 0.55 eV, in which much smaller cutoff energy value, as low as 0.1 eV, needs to be used.

The isomeric thermal neutron cross section and isomeric resonance integral of 109 Ag(n, γ) 110m Ag, 133 Cs(n, γ) 134m Cs and 134g Cs, and 136 Ba(n, γ) 137m Ba reactions were investigated together with 115 In(n, γ) 116m In monitor reaction. These residual nuclei have broad half-life time scale suitable for our investigation. Moderated neutrons from steady AmBe source were used for activation of samples with natural abundances. Field was monitored and mapped using gold and indium activation. The formulae used for neutron activation analysis were derived with emphasizing the different interpenetrations of cadmium transmission factor and self-shielding factors. The k 0 -factor for γ-rays in the residual nuclei were measured. The isomeric thermal neutron cross section and resonance integral for 115 In(n, γ) 116m In were evaluated to be 162.6 b and 2585 b. These data were used to measure the k 0 -factors; and compared to reported values to confirm the procedure. The thermal neutron cross section and resonance integral for 133 Cs(n, γ) 134m Cs were found to be 2.64±0.11 b and 42±1.7 b, respectively; while those of the 109 Ag(n, γ) 110m Ag reaction were 4.09±0.35 b and 68±6 b. Thermal neutron cross section for 136 Ba(n, γ) 137m Ba was identified as 0.032±0.003 b, while the resonance integral could not be evaluated as a result of interfering reactions. Model calculations were done using EMPIRE code to simulate isomeric ratio and compared with the experimental results. The feeding of isomeric state from neutron reaction is more sensitive to the variation of neutron flux distribution than the nucleus formation. Steady neutron field could be retained with isotopic neutron source with moderation setup and geometry of suitable homogeneity and isotropy.