No abstract available

[en] Short communication. 3 refs

[en] The purpose of this note is to point out that a drastic under-estimation of nuclear level densities for both spherical and deformed nuclei could be rather a common feature of effective interactions, which generate too weak densities of single-particle states near the chemical potential corresponding to the Fermi energy in a Fermi gas model

[en] An expression for angular momentum projected energy at small deformations is given which can, of course, be used for large deformations as well. Numerical calculations are carried out for the nucleus ¹²⁰Sn. It is shown that the Hartree-Fock-Bogolyubov theory with angular momentum projection always produces non-spherical equilibrium shapes. (Auth.)

[en] In high precision Coulomb excitation experiments α particles of 10.0, 10.5, and 10.6 MeV and ¹⁶O ions of 42.0 and 46.0 MeV were used to excite the first 2⁺ states in ^{112116118120122124}Sn. Static quadrupole moments Q(2⁺) and reduced quadrupole transition probabilities B (E2; 0⁺ → 2⁺) were extracted from intensities of particles elastically and inelastically scattered at angles near 173⁰ into an annular detector. The values of Q(2⁺) are very small and consistent with 0.0 b. These results are in agreement with theoretical predictions based on pairing plus quadrupole forces

[en] Pairing correlations have a special importance for many fermion systems. Pairing correlations have been successfully described by the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity. In this work, the pairing gap parameters as a function of nuclear temperature for ¹¹⁶Sn have been evaluated. Then the nuclear level density and entropy have been determined using BCS Hamiltonian with inclusion of pairing effects. Also temperature dependence of level density parameters has been investigated.

[en] Short note. 2 refs

No abstract available

[en] The interaction induced by the exchange of low-lying surface vibrations between pairs of orbitals close to the Fermi surface provides an important contribution to pairing correlations in superfluid nuclei. We study the spatial dependence of the pairing field obtained adding the bare and induced interaction in ¹²⁰Sn.

[en] The pairing interaction is solved exactly in the ¹¹⁴Sn nucleus using a realistic strength parameter as well as standard energy levels for the shell seniority zero states. The same single-particle and two-body Hamiltonian is treated with finite-temperature BCS and the thermal random-phase approximation. The results obtained through these calculations are compared to obtain insight about the suitability of the thermal approach to the description of nuclear phenomena