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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 this work, the semiclassical trace formula for axially symmetric harmonic oscillator potential along with spin-orbit interactions is utilized to study the effects of pairing in 160Dy (prolate system) using finite temperature Bardeen, Cooper and Schrieffer theory (FT-BCS)
[en] Recent experiments by Ruutu et al. (Phys. Rev. Lett. 77 (1996) 2514) demonstrate that the presence of walls drastically reduces the energy barrier for the nucleation of solid 4He. We suggest that this reduction is due to the replacement of a true nucleation barrier by a pinning energy of the solid–liquid interface to some wall defect. Following such ideas, we reconsider the possibility that the nucleation of superfluid 3He-B is thermally activated on walls. A good fit can be obtained for the data by Schiffer et al. (Phys. Rev. Lett. 77 (1996) 2514; Progress in Low Temperature Physics, Vol. XIV, Elsevier, Amsterdam, 1995, p. 159; Mod. Problems Condens. Matter Sci. 26 (1990) 523 and references therein) with a simple model which does not involve cosmic rays.
[en] The study presents the investigation results about the reactor poisoning by samarium-149. The researches were performed by the help of a developed model in the Matlab environment for two cases and at varying of the different initial parameters.
[en] In this work, we utilize direct 17O DNP for the characterization of non-protonated oxygens in heterogeneous catalysts. The optimal sample preparation and population transfer approach for 17O direct DNP experiments performed on silica surfaces is determined and applied to the characterization of Zr- and Y-based mesoporous silica-supported single-site catalysts.
[en] The second Virial coefficient in both classical and quantum regimes of 4He gas is investigated in the temperature range 4.2-10 K. Full quantum mechanical and classical treatments are undertaken to calculate this coefficient. The main input in computing the quantum coefficient is the 'effective' phase shifts. These are determined within the framework of the Galitskii-Migdal-Feynman formalism, using two interatomic potentials. The borderline between the classical and quantum regimes is found to depend on the temperature, the number density, and the interparticle potential. (author)
[en] Using many-body wave functions we have calculated the binding energies of a 3He impurity and a fictitious 4He impurity to a superfluid vortex. We use both a shadow wave function with distributed vorticity, ΨD, and the Onsagar–Feynman function with singular vorticity, ΨO−F. For both wave functions there was no difference in the binding energies of the mass 3 and mass 4 impurities. The binding energy was independent of the density for ΨD, but strongly density dependent for ΨO−F. The value of 2.3 K for ΨD, is somewhat smaller than the experimental estimate. Our results strongly suggest that the binding is due to the displacement of high-velocity 4He atoms from the vortex core by the impurity.
[en] Here, we present a study of neutron bubble structure for magic nuclei Z = 8, 20 (O and Ca isotopes) with a theoretical calculation by employing the well established relativistic mean field (RMF) plus BCS approach which is suitable and effective for wide range of masses and recently have been applied for the study of bubble structure