scholarly journals Application of an ab-initio -inspired energy density functional to nuclei: Impact of the effective mass and the slope of the symmetry energy on bulk and surface properties

2021 ◽  
Vol 103 (6) ◽  
Author(s):  
Stefano Burrello ◽  
Jérémy Bonnard ◽  
Marcella Grasso
2015 ◽  
Vol 51 (12) ◽  
Author(s):  
T. Duguet ◽  
M. Bender ◽  
J. -P. Ebran ◽  
T. Lesinski ◽  
V. Somà

Universe ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 71
Author(s):  
Esra Yüksel ◽  
Tomohiro Oishi ◽  
Nils Paar

Nuclear equation of state is often described in the framework of energy density functional. However, the isovector channel in most functionals has been poorly constrained, mainly due to rather limited available experimental data to probe it. Only recently, the relativistic nuclear energy density functional with an effective point-coupling interaction was constrained by supplementing the ground-state properties of nuclei with the experimental data on dipole polarizability and isoscalar monopole resonance energy in 208Pb, resulting in DD-PCX parameterization. In this work, we pursue a complementary approach by introducing a family of 8 relativistic point-coupling functionals that reproduce the same nuclear ground-state properties, including binding energies and charge radii, but in addition have a constrained value of symmetry energy at saturation density in the range J = 29, 30, …, 36 MeV. In the next step, this family of functionals is employed in studies of excitation properties such as dipole polarizability and magnetic dipole transitions, and the respective experimental data are used to validate the optimal choice of functional as well as to assess reliable values of the symmetry energy and slope of the symmetry energy at saturation.


2019 ◽  
Vol 26 ◽  
pp. 112
Author(s):  
G. Ahn ◽  
P. Papakonstantinou

Many efforts are made to determine the nuclear equation of state which governs the properties and evolution of neutron stars. Especially important is to constrain the parameters of the nuclear symmetry energy. In those efforts, nuclear energy density functional (EDF) theory has been a very useful tool, as it provides a unified framework for the description both of nuclei, which can be studied on Earth, and of infinite matter and its nuclear equation of state, which is a necessary input in the modelling of neutron stars. In the present study, a new nuclear EDF, the KIDS functional, is explored with a focus on the nuclear symmetry energy. The form of the functional allows us to vary at will the poorly constrained high-order derivatives of the symmetry energy and examine how the maximum possible mass of a neutron star is affected. Some tentative constraints on the skewness are presented, which will help guide further refinements. It is noteworthy that the pressure of neutron-rich matter is found strongly affected by skewness variations, both at low and high densities.


Author(s):  
Jeet Amrit Pattnaik ◽  
R.N. Panda ◽  
M. Bhuyan ◽  
S.K. Patra

We have systematically studied the surface properties, such as symmetry energy, neutron pressure, and symmetry energy curvature coefficient for Ne, Na, Mg, Al, and Si nuclei from the proton to neutron drip-lines. The Coherent Density Fluctuation Model (CDFM) is used to estimate these quantities taking the relativistic mean-field densities as inputs. The Br ¨uckner energy density functional is taken for the nuclear matter binding energy and local density approximation is applied for its conversion to coordinate space. The symmetry energy again decomposed to the volume and surface components within the liquid drop model formalism to the volume and surface parts separately. Before calculating the surface properties of finite nuclei, the calculated bulk properties are compared with the experimental data, whenever available. The NL3* parameter set with the BCS pairing approach in an axially deformed frame-work is used to take care of the pairing correlation when needed. The deformed density is converted to its spherical equivalent with a two Gaussian fitting, which is used as an input for the calculation of weight function in the CDFM approximation. With the help of the symmetry energy for the recently isotopes <sup>29</sup>F, <sup>28</sup>Ne, <sup>29,30</sup>Na and <sup>31,35,36</sup>Mg are considered to be within the island of inversion emphasized [Phys. Lett. B 772, 529 (2017)]. Although we get large symmetric energies corresponding to a few neutron numbers for this isotopic chain as expected, an irregular trend appears for all these considered nuclei. The possible reason behind this abnormal behavior of symmetry energy for these lighter mass nuclei is also included in the discussion, which gives a direction for future analysis.


2010 ◽  
Vol 19 (04) ◽  
pp. 794-799 ◽  
Author(s):  
M. ZALEWSKI ◽  
P. OLBRATOWSKI ◽  
W. SATUŁA

Calculations for infinite nuclear matter with realistic nucleon-nucleon interactions suggest that the isoscalar effective mass (IEM) of a nucleon at the saturation density equals m*/m ~ 0.8 ± 0.1, at variance with empirical data on the nuclear level density in finite nuclei which are consistent with m*/m ≈ 1. This contradicting results might be reconciled by enriching the radial dependence of IEM. In this work four new terms are introduced into the Skyrme-force inspired local energy-density functional: τ(∇ρ)2, [Formula: see text], τ2 and τ∆ρ. The aim is to investigate how they influence the radial dependence of IEM and, in turn, the single-particle spectra.


Sign in / Sign up

Export Citation Format

Share Document