PaperPanorama
FAQ

Nuclear Theory·nucl-th

Thursday·November 4, 2021

9 papers—5 primary·4 cross-listed

All9Primary5Cross-lists4
  1. 01

    A -rigid solution of the Bohr Hamiltonian with deformation-dependent mass term for Kratzer potential and

    S. Ait El Korchi · S. Baid · P. Buganu · M. Chabab · A. El Batoul · A. Lahbas · M. Oulne

    In this work, the Davydov-Chaban Hamiltonian, describing the collective motion of -rigid atomic nuclei, is amended by allowing the mass parameter to depend on the nuclear deformation. Further, Z(4)-DDM (Deformation-Dependent Mass) model is proposed by considering the Kratzer potential for the variable, and solving the problem by techniques of asymptotic iteration method (AIM). The results of the calculated spectra and transition rates for series of Pt isotopes are compared with the corresponding experimental data as well as with other theoretical models. Exact analytical expressions are derived for spectra and normalized wave functions of the Kratzer potential. The obtained results show an overall good agreement with the experimental data and an important improvement in respect to other models

    nucl-thBulg.J.Phys.(2021)·2 citations
  2. 02

    Efficacy of the symmetry-adapted basis for ab initio nucleon-nucleus interactions for light- and intermediate-mass nuclei

    Alexis Mercenne · Kristina D. Launey · Tomas Dytrych · Jutta E. Escher · Sofia Quaglioni · Grigor H. Sargsyan · Jerry P. Draayer

    We study the efficacy of a new ab initio framework that combines the symmetry-adapted (SA) no-core shell-model approach with the resonating group method (RGM) for unified descriptions of nuclear structure and reactions. We obtain ab initio neutron-nucleus interactions for He, O, and Ne targets, starting with realistic nucleon-nucleon potentials. We discuss the effect of increasing model space sizes and symmetry-based selections on the SA-RGM norm and direct potential kernels, as well as on phase shifts, which are the input to calculations of cross sections. We demonstrate the efficacy of the SA basis and its scalability with particle numbers and model space dimensions, with a view toward ab initio descriptions of nucleon scattering and capture reactions up through the medium-mass region.

    nucl-thComput.Phys.Commun.(2022)·20 citations
  3. 03

    Three-boson stability for boosted interactions towards the zero-range limit

    K. Mohseni🇧🇷 · A. J. Chaves🇧🇷 · D. R. da Costa🇧🇷 · T. Frederico🇧🇷 · M. R. Hadizadeh🇨🇳

    We study the three-boson bound-state mass and wave functions for ground and excited states within the three-body relativistic framework with Kamada and Glöcke boosted potentials in the limit of a zero-range interaction. We adopt a nonrelativistic short-range separable potential, with Yamaguchi and Gaussian form factors, and drive them towards the zero-range limit by letting the form factors' momentum scales go to large values while keeping the two-body binding fixed. We show that the three-boson relativistic masses and wave functions are model-independent towards the zero-range limit, and the Thomas collapse is avoided, while the nonrelativistic limit kept the Efimov effect. Furthermore, the stability in the zero-range limit is a result of the reduction of boosted potential with the increase of the virtual pair center of mass momentum within the three-boson system. Finally, we compare the present results with Light-Front and Euclidean calculations.

    nucl-thphysics.comp-phPLB(2021)·6 citations
  4. 04

    Parity and Time Reversal Invariance Violation in Neutron-Nucleus Scattering

    V. V. Flambaum🇦🇺 · A. J. Mansour🇦🇺

    Parity violating (PV) as well as parity and time-reversal invariance violating (PTRIV) effects are enhanced a million times in neutron reactions near p-wave compound resonances. We present the calculation of such effects using a statistical theory based on the properties of chaotic eigenstates and discuss a possibility to extract the strength constants of PTRIV interactions from the experimental data, including nucleon-nucleon and pion-nucleon CP-violating interactions, the QCD theta-term and the quark chromo-EDM. PV effects have random sign for all target nuclei except for 232Th, where PV effects of a positive sign have been observed for ten statistically significant p-wave resonances, with energy smaller than 250 eV. This may be an indication of a possible regular (non-chaotic) contribution to PV effects. We link this regular effect to the doublets of opposite parity states in the rotation spectra of nuclei with an octupole deformation and suggest other target nuclei where this hypothesis may be tested. We also discuss a permanent sign contribution produced by doorway states. An estimate of the ratio of PTRIV effects to PV effects is presented. Although a polarised target is not needed for the measurement of PV effects, for the interpretation of the results, it may be convenient to do both PV and PTRIV experiments with a polarised target.

    nucl-thhep-phPRC(2022)·8 citations
  5. 05

    Shell-model study of titanium isotopic chain with chiral two- and three-body forces

    L. Coraggio · G. De Gregorio · A. Gargano · N. Itaco · T. Fukui · Y. Z. Ma · F. R. Xu

    The even-even Ti isotopic chain, from A = 42 to 70, has been studied within the nuclear shell-model framework by employing an effective Hamiltonian which is derived by way of many-body perturbation theory from a chiral potential with two- and three-body forces, and includes three-body contributions which account for Pauli principle violations in nuclei with more than two valence particles. We consider 40Ca as a closed core and a model space spanned by the neutron and proton 0f1p orbitals with the addition of the 0g9/2 orbital for neutrons. Calculated two-neutron separation energies and excitation energies of the yrast 2+ states are reported and compared with the experimental data, which are available up to 62Ti. The present study intends to investigate the effects of the adopted effective interactions on the evolution of the shell structure.

    nucl-thPRC(2021)·15 citations

Affiliations

first authorsco-authorsvia INSPIRE