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[en] Highlights: • Comparative analysis of VERA benchmark was performed by code-to-code comparisons. • Sensitivity study was performed for nuclear transmutation equation solution. • Sensitivities were quantified in terms of mesh size, burnup interval, and Q-value. • Additional comparison methods were demonstrated to improve consistency of comparison. - Abstract: This paper presents a comparative analysis of the VERA depletion benchmark through consistent code-to-code comparisons between four neutronics analysis codes. An optimization of depletion calculation methods has been performed through an extensive sensitivity study in terms of nuclear transmutation equation solution methods and numerical calculation options such as mesh size, burnup intervals, and recoverable energy per fission (Q-value). An applied comparison was successfully demonstrated to improve the consistency of code-to-code depletion behavior comparisons and mitigate the adverse effects of the different kappa values of different codes by using the number density of 148Nd and a cumulative flux as a burnup indicator.
[en] In the present investigations the following observation have been made. A phase transition from the superfluid state to normal nuclear matter for temperature T ≈ 0.6MeV, and angular momentum M > 20ħ when pairing correlations are important. A shape transition from prolate collective to oblate non-collective beyond temperature T ≈ 0.6MeV and angular momentum M > 30ħ. The influence of pairing and structural changes on the level density parameter at high angular-momentum states and high excitation energies for the nucleus 148Nd on the basis of statistical theory of hot rotating nuclei (STHR)
[en] Isotope shifts and hyperfine structures of six excited levels between 17 790 cm-1 and 21 346 cm-1 in Nd I were measured by means of atomic-beam-laser spectroscopy. Anomalies caused by the second-order hyperfine perturbation between two close-lying levels were studied for 143Nd and 145Nd. It was found that the anomalous energy shifts were caused predominantly by the second-order dipole-dipole hyperfine perturbation and that the contributions of the dipole-quadrupole and the quadrupole-quadrupole perturbations were negligibly small. (author)
[en] The charge densities of the isotopes of neodymium are calculated on the basis of a modified shell model with fractional occupation numbers of the states 2 s, 2 p, and 1 h. Deformation of the nucleus and contribution of the first 2+ states to charge densities were taken into account on the basis of the collective Bohr-Mottelson model. The occupation probabilities of the states 2 s, 2 p, and 1 h were found to be 0.7, 0.4, and 0.2, respectively, and very good agreement with experiment was obtained. The transition charge densities of low-lying dipole excitations of the 146 Nd(11) and 150 Nd(11 and 12) were obtained on the basis of a microscopic model qualitatively agreeing with model-independent densities. The effect of the 2 s and 2 p shells on the charge densities was investigated