PaperPanorama

Nuclear Theory·nucl-th

Thursday·August 27, 2015

7 papers5 primary·2 cross-listed

  1. 01

    Nuclear ground-state masses and deformations: FRDM(2012)

    P. Moller · A. J. Sierk · T. Ichikawa · H. Sagawa

    We tabulate the atomic mass excesses and binding energies, ground-state shell-plus-pairing corrections, ground-state microscopic corrections, and nuclear ground-state deformations of 9318 nuclei ranging from O to . The calculations are based on the finite-range droplet macroscopic model and the folded-Yukawa single-particle microscopic model. Relative to our FRDM(1992) mass table in {\sc Atomic Data and Nuclear Data Tables} [{\bf 59} 185 (1995)], the results are obtained in the same model, but with considerably improved treatment of deformation and fewer of the approximations that were necessary earlier, due to limitations in computer power. The more accurate execution of the model and the more extensive and more accurate experimental mass data base now available allows us to determine one additional macroscopic-model parameter, the density-symmetry coefficient , which was not varied in the previous calculation, but set to zero. Because we now realize that the FRDM is inaccurate for some highly deformed shapes occurring in fission, because some effects are derived in terms of perturbations around a sphere, we only adjust its macroscopic parameters to ground-state masses. The values of ten constants are determined directly from an optimization to fit ground-state masses of 2149 nuclei ranging from O to Sg and Hs. The error of the mass model is 0.5595~MeV. We also provide masses in the FRLDM, which in the more accurate treatments now has an error of 0.6618 MeV. But in contrast to the FRDM, it is suitable for studies of fission and has been extensively so applied elsewhere, with FRLDM(2002) constants. The FRLDM(2012) fits 31 fission barrier heights from Se to Cf with a root-mean-square deviation of 1.052 MeV.

    nucl-thAtom.Data Nucl.Data Tabl.(2016)·1075 citations
  2. 02

    Calculation of Spin Observables for Proton-Proton Elastic Scattering in the Bethe-Salpeter Equation

    Susumu Kinpara

    Bethe-Salpeter equation is applied to - elastic scattering. The observables of spin are calculated in the framework of the M matrix using the two-body interaction potential. The parameter of the pseudovector coupling constant is adjusted so as to reproduce the spin singlet part. It is shown that the spin rotation and are improved by the resonance effect for .

    nucl-th1 citation
  3. 03

    Nuclear incompressibility parameters evaluated from isoscalar giant monopole resonance of , nuclide and Sn isotopes

    Shuichiro Ebata

    The isoscaler giant monopole resonances (ISGMR) are computed using the canonical-basis time-dependent Hartree-Fock-Bogoliubov theory (Cb-TDHFB) with five kinds of Skyrme parameter sets (SGII, SkM, SLy4, SkT3 and SkI3). To extract the nuclear matter property from finite system, ISGMRs of = (=20 - 50), isobar even-even nuclide for =100, 132 and Sn isotopes are analysed systematically. The magnitude relation of nuclear incompressibility-parameter () among Skyrme parameter sets, can be corresponded to the peak positions of GMR in spherical isotopes over =80. The parameters ( and ) which appear in expansion of the finite nucleus incompressibility , are determined for each Skyrme parameter. From the comparison experimental data whole mass region and the present results, they indicate that the isospin dependent term is filtered as -30510 MeV. The incompressibility parameters of {\it infinite} system corresponding to our results is =-34035, =22511, and =-13818 MeV.

    nucl-th0 citations
  4. 04

    Nuclear Reactions For Nucleosynthesis Beyond Fe

    T. Rauscher

    Many more nuclear transitions have to be known in the determination of stellar reactivities for trans-iron nucleosynthesis than for reactions of light nuclei. This requires different theoretical and experimental approaches. Some of the issues specific for trans-iron nucleosynthesis are discussed.

    nucl-thastro-ph.HEnucl-exAIP Conf.Proc.(2015)·2 citations
  5. 05

    Twist-averaged boundary conditions for nuclear pasta Hartree-Fock calculations

    B. Schuetrumpf · W. Nazarewicz

    Background: Nuclear pasta phases, present in the inner crust of neutron stars, are associated with nucleonic matter at sub-saturation densities arranged in regular shapes. Those complex phases, residing in a layer which is approximately 100 m thick, impact many features of neutron stars. Theoretical quantum-mechanical simulations of nuclear pasta are usually carried out in finite 3D boxes assuming periodic boundary conditions (PBC). The resulting solutions are affected by spurious finite-size effects. Purpose: In order to remove spurious finite-size effects, it is convenient to employ twist-averaged boundary conditions (TABC) used in condensed matter, nuclear matter, and lattice QCD applications. In this work, we study the effectiveness of TABC in the context of pasta phases simulations within nuclear density functional theory. Methods: We perform Skyrme-Hartree-Fock calculations in three dimensions by implementing Bloch boundary conditions. The TABC averages are obtained by means of Gauss-Legendre integration over twist angles. Results: We benchmark the TABC for a free nucleonic gas and apply it to simple cases such as the rod and slab phases, as well as to more elaborate P-surface and gyroidal phases. Conclusions: We demonstrate that by applying TABC reliable results can be obtained from calculations performed in relatively small volumes. By studying various contributions to the total energy, we gain insights into pasta phases in mid-density range.

    nucl-thastro-ph.HEPRC(2015)·52 citations

Affiliations

first authorsco-authorsvia INSPIRE