PaperPanorama
FAQ

Nuclear Theory·nucl-th

Tuesday·April 12, 2022

7 papers—3 primary·4 cross-listed

All7Primary3Cross-lists4
  1. 01

    [Submitted on 9 Apr 2022]

    Isospin dependent properties of the isotopic chain of Scandium and Titanium nuclei within the relativistic mean-field formalism

    Praveen K. Yadav · Raj Kumar · M. Bhuyan

    The density-dependent nuclear symmetry energy is directly related to the isospin asymmetry for finite and infinite nuclear systems. It is critical to determine the coefficients of symmetry energy and its related observables as it holds great importance in different areas of nuclear physics, such as analyzing the structure of ground state exotic nuclei and neutron star study. The ground state bulk properties such as nuclear binding energy, quadrupole deformation, two-neutron separation energy, the differential variation of two-neutron separation energy, and root-mean-square charge radius for Scandium (Z = 21), and Titanium (Z = 22) nuclei are calculated. The coherent density fluctuation model is used to estimate the isospin-dependent properties of finite nuclei such as symmetry energy and its surface and volume components from its corresponding value in infinite nuclear matter system. Finally, we correlate the neutron-skin thickness with the coefficient of symmetry energy and its related observables corresponding to these isotopic chains of nuclei. The relativistic mean-field formalism with non-linear NL3 and Relativistic-Hartree-Bogoliubov with density-dependent DD-ME2 interaction parameters are employed in the present analysis. A shape transition is observed from spherical to prolate near N 44 and N 40 for Sc- and Ti- isotopic chain, respectively. Notable signatures of shell and/or sub-shell closures have been found for the magic neutron numbers at N = 20 and 28 for both the isotopic chain using the nuclear bulk and isospin quantities. In addition to these, a few signatures of shell/sub-shell closure are observed near the drip-line region, at N = 34 and 50 by following the surface/isospin dependent observables, namely symmetry energy and its component for both the isotopic chain of odd-A Sc- and even-even Ti- nuclei.

    Comments:
    Submitted to Chinese Physics C: 15 pages, 10 figures
    Subjects:
    Nuclear Theory (nucl-th)
    arXiv:
    2204.04485 [pdf]
    CPC(2022)·15 citations
  2. 02

    [Submitted on 11 Apr 2022]

    The optimized point-coupling interaction for the relativistic energy density functional of Hartree-Bogoliubov approach quantifying the nuclear bulk properties

    Zi Xin Liu · Yi Hua Lam · Ning Lu · Peter Ring

    We propose a newly optimized nonlinear point-coupling parameterized interaction, PC-L3R, for the relativistic Hartree-Bogoliubov framework with a further optimized separable pairing force by fitting to observables, i.e., the binding energies of 91 spherical nuclei, charge radii of 63 nuclei, and 12 sets of mean pairing gaps consisting of 54 nuclei in total. The separable pairing force strengths of proton and neutron are optimized together with the point-coupling constants, and are justified in satisfactory reproducing the empirical pairing gaps. The comparison of experimental binding energies compiled in AME2020 for 91 nuclei with the ones generated from the present and other commonly used point-coupling interactions indicates that the implementation of PC-L3R in relativistic Hartree-Bogoliubov yields the lowest root-mean-square deviation. The charge radii satisfactory agree with experiment. Meanwhile, PC-L3R is capable of estimating the saturation properties of the symmetric nuclear matter and of appropriately predicting the isospin and mass dependence of binding energy. The experimental odd-even staggering of single nucleon separation energies is well reproduced. The comparison of the estimated binding energies for 7,373 nuclei based on the PC-L3R and other point-coupling interactions is also presented.

    Comments:
    Accepted by Physics Letters B on 30 April 2023. To appear at Physics Letters B (Open Access). 16 pages, 11 figures (colorblind-friendly colors), 7 tables. This version presents the PC-L3R interaction. The first version (arXiv:2204.05159v1) presents the PC-L3 interaction
    Subjects:
    Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
    arXiv:
    2204.05159 [pdf]
    PLB(2023)·15 citations
  3. 03

    [Submitted on 11 Apr 2022]

    Hyperons, deconfinement and the speed of sound in neutron stars

    R. M. Aguirre🇦🇷

    The effects of the presence of hyperons and a phase transition to deconfined quark matter on the speed of sound in neutron stars is investigated. For this purpose a composite description consisting of a model of the covariant field theory of hadrons and one for unbound quarks are used. A phase transition with continuous and monotonous variation of the equation of state is assumed. The predictions are contrasted with recent observational data on isolated neutron stars as well as on binary systems. Only one candidate is finally obtained from six different descriptions. According to the present calculations the onset of the hyperons causes the equilibrium speed of sound to exceed the conformal limit. Qualitative agreement with recent work about the influence of the speed of sound on the g-modes of oscillation in neutron stars is obtained.

    Comments:
    Matches the published version
    Subjects:
    Nuclear Theory (nucl-th); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics — Phenomenology (hep-ph)
    arXiv:
    2204.05221 [pdf]
    PRD(2022)·10 citations

Affiliations

first authorsco-authorsvia INSPIRE