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Cranking the semimicroscopic algebraic cluster model
Yépez-Martínez, H;Hess, P.O.;
Revista mexicana de física , 2008,
Abstract: initial steps are presented on the cranking of the semimicroscopic algebraic cluster model (sacm). this permits to treat hamiltonians which do not present a dynamical symmetry.
Analytical expressions of the dispersive contributions of the nuclear optical model  [PDF]
J. M. Quesada,R. Capote,J. Raynal,A. Molina,M. Lozano
Physics , 2002, DOI: 10.1103/PhysRevC.67.067601
Abstract: Analytical solutions of dispersion relations in the nuclear optical model have been found for both imaginary volume and surface potentials. A standard Brown-Rho shape has been assumed for the volume imaginary term and a Brown-Rho shape multiplied by a decreasing exponential for the surface contribution. The analytical solutions are valid for any even value of the exponent appearing in these functional forms.
Semimicroscopic algebraic description of $α$-clustering in $^{22}$Ne  [PDF]
G. Lévai
Physics , 2013, DOI: 10.1103/PhysRevC.88.014328
Abstract: The alpha-cluster states of $^{22}$Ne are studied within the framework of the semimicroscopic algebraic cluster model (SACM). The band structure, energy spectrum as well as E2 and E1 transitions are calculated and are compared with the experimental data. The results are also compared with those obtained from two microscopic models: the deformed-basis antisymmetrized molecular dynamics (DAMD) approach and the generator-coordinate method (GCM). It is found that the prominent bands obtained in the latter frameworks all have equivalents in the SACM and the agreement between the calculated spectroscopic properties is rather good, especially for positive-parity states.
Influence by small dispersive coal dust particles of different fractional consistence on characteristics of iodine air filter at nuclear power plant  [PDF]
I. M. Neklyudov,O. P. Ledenyov,L. I. Fedorova,P. Ya. Poltinin
Physics , 2013,
Abstract: The main purpose of research is to determine the influence by the small dispersive coal dust particles of the different fractional consistence on the technical characteristics of the vertical iodine air filter at nuclear power plant. The research on the transport properties of the small dispersive coal dust particles in the granular filtering medium of absorber in the vertical iodine air filter is completed in the case, when the modeled aerodynamic conditions are similar to the real aerodynamic conditions. It is shown that the appearance of the different fractional consistence of small dispersive coal dust particles with the decreasing dimensions down to the micro and nano sizes at the action of the air dust aerosol stream normally results in a significant change of distribution of the small dispersive coal dust particles masses in the granular filtering medium of an absorber in the vertical iodine air filter, changing the vertical iodine air filter aerodynamic characteristics. The precise characterization of the aerodynamic resistance of a model of the vertical iodine air filter is completed. The comparative analysis of the technical characteristics of the vertical and horizontal iodine air filters is also made.
Folding model study of the isobaric analog excitation: isovector density dependence, Lane potential and nuclear symmetry energy  [PDF]
Dao T. Khoa,Hoang Sy Than,Do Cong Cuong
Physics , 2007, DOI: 10.1103/PhysRevC.76.014603
Abstract: A consistent folding model analysis of the ($\Delta S=0, \Delta T=1$) charge exchange \pn reaction measured with $^{48}$Ca, $^{90}$Zr, $^{120}$Sn and $^{208}$Pb targets at the proton energies of 35 and 45 MeV is done within a two-channel coupling formalism. The nuclear ground state densities given by the Hartree-Fock-Bogoljubov formalism and the density dependent CDM3Y6 interaction were used as inputs for the folding calculation of the nucleon optical potential and \pn form factor. To have an accurate isospin dependence of the interaction, a complex isovector density dependence of the CDM3Y6 interaction has been carefully calibrated against the microscopic Brueckner-Hatree-Fock calculation by Jeukenne, Lejeune and Mahaux before being used as folding input. Since the isovector coupling was used to explicitly link the isovector part of the nucleon optical potential to the cross section of \pn reaction exciting the 0$^+$ isobaric analog states in $^{48}$Sc, $^{90}$Nb, $^{120}$Sb and $^{208}$Bi, the newly parameterized isovector density dependence could be well tested in the folding model analysis of the \pn reaction. The isospin- and density dependent CDM3Y6 interaction was further used in the Hartree-Fock calculation of asymmetric nuclear matter, and a realistic estimation of the nuclear symmetry energy has been made.
Radial basis function approach in nuclear mass predictions  [PDF]
Z. M. Niu,Z. L. Zhu,Y. F. Niu,B. H. Sun,T. H. Heng,J. Y. Guo
Physics , 2013, DOI: 10.1103/PhysRevC.88.024325
Abstract: The radial basis function (RBF) approach is applied in predicting nuclear masses for 8 widely used nuclear mass models, ranging from macroscopic-microscopic to microscopic types. A significantly improved accuracy in computing nuclear masses is obtained, and the corresponding rms deviations with respect to the known masses is reduced by up to 78%. Moreover, strong correlations are found between a target nucleus and the reference nuclei within about three unit in distance, which play critical roles in improving nuclear mass predictions. Based on the latest Weizs\"{a}cker-Skyrme mass model, the RBF approach can achieve an accuracy comparable with the extrapolation method used in atomic mass evaluation. In addition, the necessity of new high-precision experimental data to improve the mass predictions with the RBF approach is emphasized as well.
Folding model study of the charge-exchange scattering to the isobaric analog state and implication for the nuclear symmetry energy  [PDF]
Dao T. Khoa,Bui Minh Loc,Dang Ngoc Thang
Physics , 2013, DOI: 10.1140/epja/i2014-14034-9
Abstract: The Fermi transition (\Delta L=\Delta S=0 and \Delta T=1) between the nuclear isobaric analog states (IAS), induced by the charge-exchange (p,n) or (3He,t) reaction, can be considered as "elastic" scattering of proton or 3He by the isovector term of the optical potential (OP) that flips the projectile isospin. The accurately measured (p,n) or (3He,t) scattering cross-section to the IAS can be used, therefore, to probe the isospin dependence of the proton or 3He optical potential. Within the folding model, the isovector part of the OP is determined exclusively by the neutron-proton difference in the nuclear densities and the isospin dependence of the effective nucleon-nucleon (NN) interaction. Because the isovector coupling explicitly links the isovector part of the proton or 3He optical potential to the cross section of the charge-exchange (p,n) or (3He,t) scattering to the IAS, the isospin dependence of the effective (in-medium) NN interaction can be well tested in the folding model analysis of these charge-exchange reactions. On the other hand, the same isospin- and density dependent NN interaction can also be used in a Hartree-Fock calculation of asymmetric nuclear matter, to estimate the nuclear matter energy and its asymmetry part (the nuclear symmetry energy). As a result, the fine-tuning of the isospin dependence of the effective NN interaction against the measured (p,n) or (3He,t) cross sections should allow us to make some realistic prediction of the nuclear symmetry energy and its density dependence.
Use of the Discrete Variable Representation Basis in Nuclear Physics  [PDF]
Aurel Bulgac,Michael McNeil Forbes
Physics , 2013, DOI: 10.1103/PhysRevC.87.051301
Abstract: The discrete variable representation (DVR) basis is nearly optimal for numerically representing wave functions in nuclear physics: Suitable problems enjoy exponential convergence, yet the Hamiltonian remains sparse. We show that one can often use smaller basis sets than with the traditional harmonic oscillator basis, and still benefit from the simple analytic properties of the DVR bases which requires no overlap integrals, simply permit using various Jacobi coordinates, and admit straightforward analyses of the ultraviolet and infrared convergence properties.
Nuclear mass predictions with radial basis function approach  [PDF]
Ning Wang,Min Liu
Physics , 2011, DOI: 10.1103/PhysRevC.84.051303
Abstract: With the help of radial basis function (RBF) and the Garvey-Kelson relation, the accuracy and predictive power of some global nuclear mass models are significantly improved. The rms deviation between predictions from four models and 2149 known masses falls to about 200 keV. The AME95-03 and AME03-Border tests show that the RBF approach is a very useful tool for further improving the reliability of mass models. Simultaneously, the differences from different model predictions for unknown masses are remarkably reduced and the isospin symmetry is better represented when the RBF extrapolation is combined.
Low Energy alpha-alpha Semimicroscopic Potentials  [PDF]
M. Lassaut,F. Carstoiu,V. Balanica
Physics , 2013,
Abstract: The $\alp-\alp$ interaction potential is obtained within the double folding model with density-dependent Gogny effective interactions as input. The one nucleon knock-on exchange kernel including recoil effects is localized using the Perey-Saxon prescription at zero energy. The Pauli forbidden states are removed thanks to successive supersymmetric transformations. Low energy experimental phase shifts, calculated from the variable phase approach, as well as the energy and width of the first $0^+$ resonance in $^8$Be are reproduced with high accuracy.
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