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We present a gauge-origin invariant exact two-component (X2C) approach within a modern density functional framework, supporting meta-generalized gradient approximations such as TPSS and range-separated hybrid functionals such as CAM-B3LYP. The complete exchange-correlation kernel is applied, including the direct contribution of the field-dependent basis functions and the reorthonormalization contribution from the perturbed overlap matrix. Additionally, the finite nucleus model is available for the electron-nucleus potential and the vector potential throughout. Efficiency is ensured by the diagonal local approximation to the unitary decoupling transformation in X2C as well as the (multipole-accelerated) resolution of the identity approximation for the Coulomb term (MARI-J, RI-J) and the seminumerical exchange approximation. Errors introduced by these approximations are assessed and found to be clearly negligible. The applicability of our implementation to large-scale calculations is demonstrated for a tin pincer-type system as well as low-valent tin and lead complexes. Here, the calculation of the Sn nuclear magnetic resonance shifts for the pincer-type ligand with about 2400 basis functions requires less than 1 h for hybrid density functionals. Further, the impact of spin–orbit coupling on the nucleus-independent chemical shifts and the corresponding ring currents of all-metal aromatic systems is studied. [ABSTRACT FROM AUTHOR]

The concept of symmetry under various transformations of quantities describing basic natural phenomena is one of the fundamental principles in the mathematical formulation of physical laws. Starting with Noether's theorems, we highlight some well–known examples of global symmetries and symmetry breaking on the particle level, such as the separation of strong and electroweak interactions and the Higgs mechanism, which gives mass to leptons and quarks. The relation between symmetry energy and charge symmetry breaking at both the nuclear level (under the interchange of protons and neutrons) and the particle level (under the interchange of u and d quarks) forms the main subject of this work. We trace the concept of symmetry energy from its introduction in the simple semi-empirical mass formula and liquid drop models to the most sophisticated non-relativistic, relativistic, and ab initio models. Methods used to extract symmetry energy attributes, utilizing the most significant combined terrestrial and astrophysical data and theoretical predictions, are reviewed. This includes properties of finite nuclei, heavy-ion collisions, neutron stars, gravitational waves, and parity–violating electron scattering experiments such as CREX and PREX, for which selected examples are provided. Finally, future approaches to investigation of the symmetry energy and its properties are discussed. [ABSTRACT FROM AUTHOR]

In the present work, we investigate the bulk properties of nuclear matter and neutron stars with the newly proposed relativistic interaction NL-RS which provides an opportunity to readjust the coupling constants keeping in view the properties of finite nuclei, nuclear matter, PREX-II results for neutron skin thickness in 208Pb and astrophysical observations. The NL-RS model interaction has been proposed by fitting the ground state properties (binding energies and charge radii) of finite nuclei, bulk nuclear matter properties, and PREX-II results for neutron skin thickness of 208Pb. The relativistic interaction has been generated by including nonlinear self-interactions of σ and ω μ -mesons and mixed interactions of ω μ , and ρ μ -meson up to the quartic order. The proposed interaction harmonizes with the finite nuclei, bulk nuclear matter, and neutron star properties. A covariance analysis is performed to assess the statistical uncertainties on the model parameters and nuclear observables of interest along with correlations amongst them. The equation of state (EoS) composed of nucleons and leptons in β -equilibrium is computed with the proposed parameter set and used to study the neutron star structure. The maximum mass of the neutron star by employing the EoS computed with the NL-RS parameter set is 2.04 ± 0.03 M ⊙ and the radius of a canonical mass neutron star (R 1.4) comes out to be equal to 13.06 ± 0.16 Km. The value of dimensionless tidal deformability, for canonical mass, is 602.23 ± 33.13 which satisfies the constraints of waveform models analysis of GW170817 within 90% confidence level. [ABSTRACT FROM AUTHOR]

We propose a new method for calculating spectra and luminosities for (anti)neutrinos produced in the pre-supernova environment by weak processes with hot nuclei. It is based on the thermal quasiparticle random phase approximation (TQRPA), which allows microscopic thermodynamically consistent calculations of the weak interaction response of nuclei at finite temperatures. For realistic representative pre-supernova conditions from the stellar evolution code MESA, we compute (anti)neutrino luminosities and spectra arising from neutral- and charged-current weak reactions with hot 56Fe and compare them with the contribution of thermal processes. We find that the TQRPA approach produces not only a higher total luminosity of electron neutrinos (mainly born in the electron capture reaction), compared to the standard technique based on the large-scale shell model (LSSM) weak interaction rates, but also a harder neutrino spectrum. Besides, applying the TQRPA and LSSM, we find that in the context of electron antineutrino generation, the neutral-current nuclear de-excitation (ND) process via neutrino-antineutrino pair emission is at least as important as the electron–positron pair annihilation process. We also show that flavour oscillations enhance the high-energy contribution of the ND process to the electron antineutrino flux. This could potentially be important for pre-supernova antineutrino registration by the Earth's detectors. [ABSTRACT FROM AUTHOR]

In the present work, we constrain the equations of the state of asymmetric dense matter in consideration of the heaviest observed neutron star mass M max = 2.35 ± 0.17 M ⊙ for the black widow pulsar PSR J0952-0607, finite and bulk nuclear properties. We propose four interactions for the relativistic mean field model which include different combinations of non-linear, self, and cross-couplings among isoscalar–scalar σ , isoscalar–vector ω , isovector–vector ρ and isovector–scalar meson δ meson fields up to the quartic order. These interactions harmonize with the finite nuclei and bulk nuclear matter properties. It is observed that interactions obtained with the inclusion of δ meson coupling with nucleons have a significant effect on the slope of symmetry energy (L), radius (R 1.4 ) , and dimensionless tidal deformability (Λ 1.4) corresponding to a canonical mass neutron star. The radius of 2.08 M ⊙ neutron star mass is predicted to be in the range R 2.08 = 12.98–13.34 km which also satisfies the NICER observations Miller et al. (Astrophys. J. Lett. 918, L28 (2021). [ABSTRACT FROM AUTHOR]

The foundation and applications of the Barcelona Catania Paris Madrid (BCPM) energy density functional are briefly reviewed. BCPM uses a paradigm more rooted on density functional theory and fits most of its parameters to sophisticated microscopic nuclear matter calculations. Finite nuclei are accounted for by introducing a direct finite range surface term, spin orbit potential, Coulomb interaction and pairing. Applications of this functional to the calculation of finite nuclei properties are presented as well as applications to the description of neutron star physics. The large number of applications discussed are possible because of the local character of the functional that simplifies enormously calculations in finite nuclei. [ABSTRACT FROM AUTHOR]

The incompressibility of both nuclear matter and finite nuclei is estimated by the monopole compression modes in nuclei in the framework of a nonrelativistic Hartree–Fock–Bogoliyubov method and the coherent density fluctuation model. The monopole states originate from vibrations of the nuclear density. The calculations in the model for the incompressibility in finite nuclei are based on the Brueckner energy–density functional for nuclear matter. Results for the energies of the breathing vibrational states and finite nuclei incompressibilities are obtained for various nuclei and their values are compared with recent experimental data. The evolution of the isoscalar giant monopole resonance (ISGMR) along Ni, Sn, and Pb isotopic chains is discussed. This approach can be applied to analyses of neutron stars properties, such as incompressibility, symmetry energy, slope parameter, and other astrophysical quantities, as well as for modelling dynamical behaviors within stellar environments.

A system of baryons is studied where the system consists of the nucleon (N) and its first excited delta (Δ ). The present study investigates the double magic nucleus 56 Ni under compression. To achieve the aim of this study, a technique called constrained spherical Hartree–Fock (CSHF) is employed. The effective potential of N–N, N– Δ and Δ – Δ is used. Examination of the sensitivity for results on the model space is studied. For a large model space, the compressibility of the nuclear system increases. By increasing the model space, the radial density distribution and the formation of Δ s decrease. Then the nucleus becomes more bounded under compression by increasing the model space when delta resonances have occurred. The formation of Δ s is an increment to 8.93% of all components of 56 Ni nucleus. Under compression, a part of the increment in binding energy creates Δ particles. [ABSTRACT FROM AUTHOR]

This article presents a classical potential used to describe nucleon–nucleon interactions at intermediate energies. The potential depends on the relative momentum of the colliding nucleons and can be used to describe interactions at low momentum transfer mimicking the Pauli exclusion principle. We use the potential with molecular dynamics to study finite nuclei, their binding energy, radii, symmetry energy, and a case study of collisions. [ABSTRACT FROM AUTHOR]

The incompressibility of both nuclear matter and finite nuclei is estimated by the monopole compression modes in nuclei in the framework of a nonrelativistic Hartree–Fock–Bogoliyubov method and the coherent density fluctuation model. The monopole states originate from vibrations of the nuclear density. The calculations in the model for the incompressibility in finite nuclei are based on the Brueckner energy–density functional for nuclear matter. Results for the energies of the breathing vibrational states and finite nuclei incompressibilities are obtained for various nuclei and their values are compared with recent experimental data. The evolution of the isoscalar giant monopole resonance (ISGMR) along Ni, Sn, and Pb isotopic chains is discussed. This approach can be applied to analyses of neutron stars properties, such as incompressibility, symmetry energy, slope parameter, and other astrophysical quantities, as well as for modelling dynamical behaviors within stellar environments. [ABSTRACT FROM AUTHOR]

In this paper, the SHARK integral generation and digestion engine is described. In essence, SHARK is based on a reformulation of the popular McMurchie/Davidson approach to molecular integrals. This reformulation leads to an efficient algorithm that is driven by BLAS level 3 operations. The algorithm is particularly efficient for high angular momentum basis functions (up to L = 7 is available by default, but the algorithm is programmed for arbitrary angular momenta). SHARK features a significant number of specific programming constructs that are designed to greatly simplify the workflow in quantum chemical program development and avoid undesirable code duplication to the largest possible extent. SHARK can handle segmented, generally and partially generally contracted basis sets. It can be used to generate a host of one‐ and two‐electron integrals over various kernels including, two‐, three‐, and four‐index repulsion integrals, integrals over Gauge Including Atomic Orbitals (GIAOs), relativistic integrals and integrals featuring a finite nucleus model. SHARK provides routines to evaluate Fock like matrices, generate integral transformations and related tasks. SHARK is the essential engine inside the ORCA package that drives essentially all tasks that are related to integrals over basis functions in version ORCA 5.0 and higher. Since the core of SHARK is based on low‐level basic linear algebra (BLAS) operations, it is expected to not only perform well on present day but also on future hardware provided that the hardware manufacturer provides a properly optimized BLAS library for matrix and vector operations. Representative timings and comparisons to the Libint library used by ORCA are reported for Intel i9 and Apple M1 max processors. [ABSTRACT FROM AUTHOR]

The elasticity of neutron star crust is important for adequate interpretation of observations. To describe elastic properties one should rely on theoretical models. The most widely used is Coulomb crystal model (system of point-like charges on neutralizing uniform background), in some works it is corrected for electron screening. These models neglect finite size of nuclei. This approximation is well justified except for the innermost crustal layers, where nuclei size becomes comparable with the inter-nuclear spacing. Still, even in those dense layers it seems reasonable to apply the Coulomb crystal result, if one assumes that nuclei are spherically symmetric: Coulomb interaction between them should be the same as interaction between point-like charges. This argument is indeed correct; however, as we point here, shear of crustal lattice generates (microscopic) quadrupole electrostatic potential in a vicinity of lattice cites, which induces deformation on the nuclei. We analyse this problem analytically within compressible liquid drop model. In particular, for ground state crust composition the effective shear modulus is reduced for a factor of |$1-u^{5/3}/(2+3\, u-4\, u^{1/3})$|⁠ , where u is the ratio of the nuclei volume to the volume of the cell. This result is universal, i.e. it does not depend on the applied nucleon interaction model within applied approach. For the innermost layers of inner crust u ∼ 0.2 leading to reduction of the shear modulus by |$\sim 25{{\ \rm per\ cent}}$|⁠ , which can be important for correct interpretation of quasi-periodic oscillations in the tails of magnetar flares. [ABSTRACT FROM AUTHOR]

Lumbar disc herniation (LDH) is a common condition which can lead to back pain. Although surgical treatments for LDH are well established, complications such as spinal instability and narrowing of adjacent facet joints are still frequently reported. The purpose of this study was to use finite element models to evaluate the stability of the L3–L4 segment after conservative or aggressive percutaneous transforaminal endoscopic discectomy (PTED) with and without an artificial material filler to correct LDH. Compared to the intact model, aggressive PTED reduced the stability of the segment (increased ROM) and narrowed the space between facet joints in the medial/lateral (ML) direction during flexion (maximum 6.7 degrees change in ROM and 90.5% spacing between facet joints), extension (maximum 2.1 degrees and 38.6%), and axial rotation (maximum 4.2 degrees and 90.1%). Aggressive PTED had a similar effect in the anterior/posterior (AP) direction during lateral bending (maximum 2.0 degrees and 44.2%). Augmenting the nucleus pulposus with a polyurethane filler after aggressive PTED improved spinal stability in both the ML and AP directions in all simulated motions, with results similar to the intact model. However, using a hydrogel filler did little to stabilize the spine, likely because the material is too soft to support the heavy, sustained loading. In conclusion, this study found that if an aggressive discectomy is required, augmenting the nucleus pulposus with a PU filler provides sufficient support to stabilize the spine, while hydrogel fillers offer little support. [ABSTRACT FROM AUTHOR]

We obtain posterior distribution of equations of state (EOSs) across a broad range of density by imposing explicitly the constraints from precisely measured fundamental properties of finite nuclei, in combination with the experimental data from heavy-ion collisions and the astrophysical observations of radius, tidal deformability and minimum-maximum mass of neutron stars. The acquired EOSs exhibit a distinct global behavior compared to those usually obtained by imposing the finite nuclei constraints implicitly through empirical values of selected key parameters describing symmetric nuclear matter and symmetry energy in the vicinity of the saturation density. The explicit treatment of finite nuclei constraints yields softer EOSs at low densities which eventually become stiffer to meet the maximum mass criteria. The Kullback-Leibler divergence has been used to perform a quantitative comparison of the distributions of neutron star properties resulting from the EOSs obtained from implicit and explicit finite nuclei constraints. [ABSTRACT FROM AUTHOR]

Nuclear saturation is a crucial feature in nuclear physics that plays a fundamental role in understanding various nuclear phenomena, ranging from properties of finite nuclei to those of neutron stars. However, a proper description of nuclear saturation is highly nontrivial in modern nonrelativistic ab initio studies because of the elusive three-body forces. In this letter, we calculate the equation of state for nuclear matter in the relativistic Brueckner-Hartree-Fock (RBHF) framework with the leading order covariant chiral nuclear force. We show that a simultaneous description of the nucleon-nucleon scattering data and the saturation of the symmetric nuclear matter can be achieved. In this regard, the relativistic effects nicely explain the saturation of nuclear matter. As a result, the present study based on the covariant chiral nuclear force shows that in the RBHF framework, one can achieve saturation with a leading order covariant chiral nuclear force with only two-body forces, in contrast to the vast majorities of studies in the non-relativistic framework, where the next-to-next-to-leading order two-body and three-body chiral forces are needed. This study sets the foundation for studying nuclear saturation with the covariant chiral force in the RBHF framework, which allows for a systematic understanding of one of the key features of nuclear physics more microscopically. [ABSTRACT FROM AUTHOR]

This work presents a refinement of the finite strip method (FSM) based on the Carrera unified formulation (CUF) and is applied to free vibration analysis of variable stiffness composite laminated (VSCL) plates. VSCL plates considered here are composed of layers with curvilinear fibers in which their orientation angle changes linearly with respect to one of the in‐plane coordinates. The FSM permits the plate to be divided into some finite strips connected along the so‐called nodal lines. The conventional finite strip method involves an approximation of the solution of a plate problem by using continuously harmonic series in the longitudinal direction along the nodal lines and simple polynomial shape functions (the usual beam shape functions) in the transverse direction of the plate. However, refined finite strip model that presented in this paper allows one to express the unknown variables as a set of thickness functions that only depend on the thickness coordinate and the corresponding variable that depends on the in‐plane coordinates which involve continuously harmonic series and polynomial shape functions. Thanks to this new finite strip model, the shape functions used in the transverse direction can be chosen as 1D bar shape functions, and also, all three components of the displacement field are considered in each nodal line. Moreover, based on this approach, three‐dimensional displacement field is approximated in a compact form as a generic N‐order expansion. Therefore, explicit expressions of fundamental nuclei of finite strip matrices are obtained in a compact form and presented here. The results obtained by the present formulation for VSCL plates are compared with those obtained from published data. The results show that this kind of strip is efficient and useful. Further, several numerical examples are presented, and the effect of the order of expansion, the number of strips, curvilinear fiber angle, and various boundary conditions are examined. [ABSTRACT FROM AUTHOR]

An experiment is being carried out at J-PARC -- Japan Proton Accelerator Research Complex -- to study the origin of hadron mass and the partial restoration of chiral symmetry of quantum chromodynamics in a finite density matter. The experiment, which is called the J-PARC E16 experiment, aims to measure the mass spectra of vector mesons in nuclei due to finite density effects. Previous measurements were performed at KEK-PS proton synchrotron and showed mass modifications of vector mesons in nuclei. A new experiment aims to confirm the results of KEK-PS with larger statistics to have a detailed study. Mass spectra of vector mesons are measured using electron--positron decays in proton-nucleus reactions. A new beam line is built to provide a high-intensity proton beam for the experiment, and decayed electrons and positrons are detected and identified by a newly constructed spectrometer. The experiment started the acquisition of pilot data to evaluate the performances of the beam line and the spectrometer in 2020 and 2021. The spectrometer worked well, and physics data taking will start in 2023. [ABSTRACT FROM AUTHOR]

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 Brückner 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 Bardeen–Cooper–Schrieffer (BCS) pairing approach in an axially deformed framework 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, the isotopes 29F, 28Ne, 29,30Na, and 31,35,36Mg are considered to be within the island of inversion (Han et al. Phys. Lett. B, 772, 529 (2017). doi:10.1016/j.physletb.2017.07.007). Although we get large symmetry 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. [ABSTRACT FROM AUTHOR]

Assuming that the core of a large finite nucleus in which the neutron number (N) is quite large compared to the proton number (Z), is composed of neutron-proton pairs (which are deutrons and bosons) and the unpaired neutrons stay in the surface region (neutron skin region), A model is proposed in which the deutrons in the core interact with the neutrons in the surface region. The nucleus is considered as an assembly of a mixture of interacting bosons (deutrons) and fermions (neutrons) and the model Hamiltonian is diagonalized to calculate the quasi-particle energy of the interacting system. The low value of the quasi-particle energy per neutron when compared to the large binding fraction can lead to a march towards the dripline for the neutrons. [ABSTRACT FROM AUTHOR]

Designer nuclei are those nuclei that rarely exist in nature as stable nuclei. They are a consequence of the fabrication process at the scale of atomic nuclei. Designer atomic nuclei are new, rare isotopes, with unusual numbers of protons or neutrons with unusual decay modes. For instance, super heavy isotopes of light elements such as 113Li, have a very high ratio of neutrons to protons (N/Z = 8/3) such that the neutrons in 113Li have very low binding energy. The size of 113Liis roughly 10/fm= 10-14m(it stretches to a longer size) which corresponds to roughly ten times the volume of the stable 113Li6 nucleus, and it has the size of 86Ra 220 nucleus. The 113Li nucleus has a diffuse surface of neutron matter, and this is due the fact that quantum mechanically the wave function of the neutrons can extend far beyond the normal range of the nucleus. The existence of such nuclei allows the study of interaction of neutrons in pure neutron matter, such as neutrons stars, and also in the case of finite nuclei X Z N where N > Z. In such a system it can be assumed that the core of the nucleus is made up of Z neutron-proton pairs (deuterons) which are surrounded by the unpaired neutrons (N-Z). As the neutron number becomes very large compared to the proton number, variation of the charge radius of the nucleus can also be studied. Such calculations can assist in the development of new nuclear theory. [ABSTRACT FROM AUTHOR]

The secondary component of the GW190814 event left us with a question, "whether it is a supermassive neutron star or lightest black-hole?" Recently, Fattoyev et al. obtained an energy density functional (EDF) named as BigApple, which reproduces the mass of the neutron star is 2.60 M ⊙ which is well consistent with GW190814 data. This study explores the properties of finite nuclei, nuclear matter and neutron stars by using the BigApple EDF along with four well-known relativistic mean-field forces, namely NL3, G3, IOPB-I and FSUGarnet. The finite nuclei properties like binding energy per particle, skin thickness, charge radius, single-particle energy, and two-neutron separation energy are well predicted by the BigApple for a series of nuclei. The calculated nuclear matter quantities, such as incompressibility, symmetry energy and slope parameters at saturation density, are consistent with the empirical or experimental values where ever available. The predicted canonical tidal deformability by the BigApple parameter set is well-matched with the GW190814 data. Also, the dimensionless moment of inertia lies in the range given by the analysis of PSR J0737-3039A. [ABSTRACT FROM AUTHOR]

The |$\Xi$| single-particle potential obtained in nuclear matter with next-to-leading-order baryon–baryon interactions in chiral effective field theory is applied to finite nuclei by an improved local-density approximation method. As a premise, phase shifts of |$\Xi N$| elastic scattering and the results of Faddeev calculations for the |$\Xi NN$| bound state problem are presented to show the properties of the |$\Xi N$| interactions in the present parametrization. First, the |$\Xi$| states in |$^{14}$| N are revisited because of recent experimental progress, including discussion on the |$\Xi N$| spin–orbit interaction that is relevant to the location of the |$p$| -state. Then the |$\Xi$| levels in |$^{56}$| Fe are calculated. In particular, the level shift which is expected to be measured experimentally in the near future is predicted. The smallness of the imaginary part of the |$\Xi$| single-particle potential is explicitly demonstrated. [ABSTRACT FROM AUTHOR]

Pairing correlation of Cooper pair is a fundamental property of multi-fermion interacting systems. For nucleons, two modes of the Cooper-pair coupling may exist, namely of S 12 = 0 with L 12 = 0 (spin-singlet s-wave) and S 12 = 1 with L 12 = 1 (spin-triplet p-wave). In nuclear physics, it has been an open question whether the spin-singlet or spin-triplet coupling is dominant, as well as how to measure their role. We investigate a relation between the magnetic-dipole (M1) excitation of nuclei and the pairing modes within the framework of relativistic nuclear energy-density functional (RNEDF). The pairing correlations are taken into account by the relativistic Hartree-Bogoliubov (RHB) model in the ground state, and the relativistic quasi-particle random-phase approximation (RQRPA) is employed to describe M1 transitions. We have shown that M1 excitation properties display a sensitivity on the pairing model involved in the calculations. The systematic evaluation of M1 transitions together with the accurate experimental data enables us to discern the pairing properties in finite nuclei. [ABSTRACT FROM AUTHOR]

A unified description of finite nuclei and equation of state of neutron stars presents both a major challenge and also opportunities for understanding nuclear interactions. Inspired by the Lee–Huang–Yang formula of hard-sphere gases, we develop effective nuclear interactions with an additional high-order density dependent term. While the original Skyrme force SLy4 is widely used in studies of neutron stars, there are not satisfactory global descriptions of finite nuclei. The refitted SLy4' force can improve descriptions of finite nuclei but slightly reduces the radius of neutron star of 1.4M⊙ with M⊙ being the solar mass. We find that the extended SLy4 force with a higher-order density dependence can properly describe properties of both finite nuclei and GW170817 binary neutron stars, including the mass-radius relation and the tidal deformability. This demonstrates the essential role of high-order density dependence at ultrahigh densities. Our work provides a unified and predictive model for neutron stars, as well as new insights for the future development of effective interactions. [ABSTRACT FROM AUTHOR]

When hadron-quark continuity is formulated in terms of a topology change at a density higher than twice the nuclear matter density (n 0) , the core of massive compact stars can be described in terms of quasiparticles of fractional baryon charges, behaving neither like pure baryons nor like deconfined quarks. Hidden symmetries, both local gauge and pseudo-conformal (or broken scale), emerge and give rise both to the long-standing "effective g A ∗ ≈ 1 " in nuclear Gamow–Teller (GT) transitions at ≲ n 0 and to the pseudo-conformal sound velocity v pcs 2 / c 2 ≈ 1 / 3 at ≳ 3 n 0 . It is suggested that what has been referred to, since a long time, as "quenched g A " in light nuclei reflects what leads to the dilaton-limit g A DL = 1 at near the (putative) infrared fixed point of scale invariance. These properties are confronted with the recent observations in GT transitions and in astrophysical observations. [ABSTRACT FROM AUTHOR]

The bridge between finite and infinite nuclear systems is analyzed for the fundamental quantities, such as binding energy, incompressibility, and giant monopole excitation energy, using relativistic mean-field formalism. The well-known Thomas–Fermi, extended Thomas–Fermi, and Hartree approximations are used to evaluate the observables. A parametric form of the density is used to convert the infinite nuclear matter density to the mean density of a finite nucleus. The present analysis shows an approximate estimation of finite nucleus properties from information on the corresponding infinite nuclear matter quantities. In other words, it is not quite exact to get the observables of finite nuclei by converting the corresponding entities of the nuclear matter system or vice versa. If this can be achieved at all, it can be done only approximately. [ABSTRACT FROM AUTHOR]

The remaining uncertainties in relation to isovector nuclear interactions call for reliable experimental measurements of isovector probes in finite nuclei. Based on the Bayesian analysis, although neutron-skin thickness data or isovector giant dipole resonance data in 208Pb can constrain only one isovector interaction parameter, correlations among other parameters can also be built. Using combined data for both the neutron-skin thickness and the isovector giant dipole resonance helps to significantly constrain all isovector interaction parameters; as such, it serves as a useful methodology for future research. [ABSTRACT FROM AUTHOR]

The nuclear matter parameters define the nuclear equation of state (EoS), they appear as coefficients of expansion around the saturation density of symmetric and asymmetric nuclear matter. We review their correlations with several properties of finite nuclei and of neutron stars within mean-field frameworks. The lower order nuclear matter parameters such as the binding energy per nucleon, incompressibility and the symmetry energy coefficients are found to be constrained in narrow limits through their strong ties with selective properties of finite nuclei. From the correlations of nuclear matter parameters with neutron star observables, we further review how precision knowledge of the radii and tidal deformability of neutron stars in the mass range 1 - 2 M ⊙ may help cast them in narrower bounds. The higher order parameters such as the density slope and the curvature of the symmetry energy or the skewness of the symmetric nuclear matter EoS are, however, plagued with larger uncertainty. From inter-correlation of these higher order nuclear matter parameters with lower order ones, we explore how they can be brought to more harmonious bounds. [ABSTRACT FROM AUTHOR]

The article presents a study of direct visualization of the columnar anionic electron density within the prototype electride Y5Si3 with sub-angstrom spatial resolution using a scanning transmission electron microscope (STEM)-differential phase-contrast (DPC) imaging. Topics discussed include the procedures for preparing Y5Si3 crystals, the use of density functional theory (DFT) calculations to understand DPC measurements, and the ability of the model to probe spatially distributed electrons.

A muonic hydrogen-like atom is formed when replacing the electron in it by a negative muon μ - . The Schrödinger equation corresponds to the one of the atoms with a binding particle (μ -) with mass M μ ≈ 207 m e , where m e is the electron mass. The muon, in comparison with the electron, moves along an orbit which remains much closer to the nucleus and the associated binding energy is considerably increased. In this report, we have studied how the ground state energy changes for H, H e + and L i + 2 muonic atoms when subjected to very high compression. In order to simulate such a compression regime for the atoms, we have considered two confinement models: In the first, we assume for each system a nuclear point mass, whereas in the second the nucleus consists of a finite volume with a uniformly distributed charge. The energy correction due to the nucleus finite size is carried out at first-order perturbation theory. We found that the maximum of the energy correction becomes more important as the confinement and mass number of the atom nucleus grow. [ABSTRACT FROM AUTHOR]

The origin of the neutron skin thickness, measured by the CREX and PREX collaborations as thin for 40Ca and thick for 28Pb, remains a mystery. We investigate the effects of tensor and nonlinear isovector–isoscalar terms in a relativistic mean-field model (RMF) on the properties of finite nuclei and nuclear matter. Tensor couplings are crucial for better quality binding energies of finite nuclei and charge radii for relatively heavy nuclei. However, for light nuclei, the tensor terms cannot improve the compatibility of charge radius predictions by the RMF model with experimental data. We find that parameter sets with a larger nonlinear isovector–isoscalar parameter, particularly η 2 ρ = 0.028, agree better with experimental data for Δ r n p across light, medium, and heavy isotope chains. Using PT28, we calculate Δ r n p for 208Pb as 0.214 fm, J as 33.078, and L as 58.426. Δ r n p for 208Pb obtained using PT28 is consistent with the PREX-II data. Moreover, the corresponding values of J and L agree with the low L constraints. Meanwhile, the canonical mass radius predicted by PT28 aligns with the mass and radius data from the NICER collaboration. The combination of tensor and nonlinear isovector–isoscalar couplings in the RMF model provides accurate predictions for finite nuclei binding energies and relatively heavy nuclei charge radii, resulting in relatively thick Δ r n p values for 208Pb without substantial L values. [ABSTRACT FROM AUTHOR]

Claude Mahaux, a professor emeritus in theoretical physics at the University of Liège, passed away on August 29, 2023. He was born on September 25, 1937, and had a distinguished career in nuclear physics. Mahaux made significant contributions to the field, particularly in the areas of the microscopic structure of the nuclear optical potential and many-body nuclear physics. He collaborated with Hans Weidenmüller on a book called "Shell Model Approach to Nuclear Reactions," which remains an important resource for researchers. Mahaux also published landmark review papers and served as the editor of Physics Letters B from 1981 to 1996. He is survived by his wife, daughter, granddaughters, and great-grandchildren. [Extracted from the article]

The ability of the Gogny forces of the D1 family to describe the nucleon-nucleus scattering is studied. To this end, we use an optical model (OM) potential built up using a semi-microscopic nuclear matter (NM) approach. The real and imaginary parts of the OM are provided by the first and second-order terms, respectively, of the Taylor expansion of the mass operator calculated within the Brueckner–Hartree–Fock (BHF) method using the reaction G-matrix built up with the effective Gogny force instead of a microscopic interaction. The optical potential in finite nuclei is obtained through the local density approximation (LDA) using the neutron and proton densities provided by a quasi-local Hartree–Fock (HF) calculation with the same Gogny force for the sake of consistency. A reasonable good agreement is found between the theoretical differential cross-sections and the analyzing powers (AP) of the elastic neutron and proton scattering along the periodic table from Ca to Pb calculated with the Gogny forces and the corresponding values predicted by the global phenomenological potential of Koning and Delaroche. To investigate the limits of the approximations used in this work, comparisons with the results of nucleon-nucleus elastic scattering in 40Ca and 48Ca obtained using the nuclear structure model (NSM) are also performed. [ABSTRACT FROM AUTHOR]

The present study investigates the isospin and Z‐dependency of the effective symmetry energy and its co‐efficient, namely, neutron pressure for the isotonic chain of neutron magic N = 40, and 82. The relativistic mean‐field model with the non‐linear NL3* parameter and Relativistic‐Hartree‐Bogoliubov approach with density‐dependent DD‐ME2 parameter sets are used for the analysis. The coherent density fluctuation model and Liquid‐Drop‐Approximation are adopted to formulate the nuclear matter observables such as symmetry energy, neutron pressure of finite nuclei at local density. We found a notable sign of the shell/sub‐shell closure following the proton magic over the isotonic chain. Further, a comparative analysis shows that the coherent density fluctuation model is a better approximation to include the surface effect of finite nuclei as compared to the Liquid‐Drop‐Approximation, which plays a significant role to determine the shell/sub‐shell closure over an isotopic and/or isotonic chain. [ABSTRACT FROM AUTHOR]

The influence of the diffuse surface layer of a finite nucleus on the mean square radii and their isotopic shift is investigated. We present the calculations within the Gibbs - Tolman approach using the experimental values of the nucleon separation energies. Results are compared with that obtained by means of a direct variational method based on Fermi-like trial functions. [ABSTRACT FROM AUTHOR]

In this study, the effect of the surface symmetry energy on the neutron skin thickness and division of it into the bulk and surface parts are investigated by determination of the symmetry energy coefficient a sym (A) of finite nuclei. We demonstrate the importance of the isospin asymmetry distribution in the symmetry energy coefficient of finite nuclei at the surface region. We attempt to find out how different surface symmetry energies may affect alpha decay half-life. The Skyrme interactions are used to describe the neutron and proton density distributions and to calculate the symmetry energy coefficient a sym (A) of four nuclei and the surface symmetry energy. The chosen Skyrme interactions can produce the binding energy and root-mean-square charge radii of both mother and daughter nuclei. We single out the spherical isotones of N = 1 2 6 named 2 0 8 Pb, 2 1 0 Po, 2 1 2 Rn and 2 1 4 Ra for daughter nuclei and explore the dependence of the bulk and surface contributions on the surface symmetry energy. The half-life of mother nuclei, i.e., 2 1 2 Po, 2 1 4 Rn, 2 1 6 Ra and 2 1 8 Th, is employed to investigate the extent to which it is affected by different surface symmetry energies. The calculated half-lives show a downward tendency for different surface symmetry energies which can be caused by various neutron skin thicknesses. [ABSTRACT FROM AUTHOR]

We review our progress on 3+1D Glasma simulations to describe the earliest stages of heavy-ion collisions. In our simulations we include nuclei with finite longitudinal extent and describe the collision process as well as the evolution of the strongly interacting gluonic fields in the laboratory frame in 3+1 dimensions using the colored particle-in-cell method. This allows us to compute the 3+1 dimensional Glasma energy-momentum tensor, whose rapidity dependence can be compared to experimental pion multiplicity data from RHIC. An improved scheme cures the numerical Cherenkov instability and paves the way for simulations at higher energies used at LHC. [ABSTRACT FROM AUTHOR]

The article clarifies the limits of ergodic assumptions in nuclear bath dynamics and provides unidentified strategies for maximizing coherence and gate fidelity of spin qubits in semiconductors. It mentions the quantum coherence and gate fidelity of electron spin qubits in semiconductors limited by nuclear spin fluctuations.

In this paper, the β−-, 2β−-, and 4β−-decay energies Q(β−), Q(2β−), and Q(4β−) given in the newly updated atomic mass evaluation (AME2016) are used to systematically constrain not only the quadratic symmetry energy coefficient and the surface-volume symmetry energy coefficient ratio , but also the quartic symmetry energy coefficient. Based on the modified Bethe–Weizsäcker mass formula, the decay energies Q(β−), Q(2β−), and Q(4β−) are all derived to be closely related to the quantities , κ, and , and then their values can be obtained by fitting the decay energies given in the AME2016. Besides, with the extracted values of and κ, by applying the relationship between the quadratic density-dependent symmetry energy S(ρ) and the mass-dependent symmetry energy coefficient of finite nuclei asym(A), the density slopes L(ρ0) for two different forms of S(ρ) at the saturation density ρ0 are constrained and the values are calculated to be L(ρ0) = 42.2 ± 8.0 MeV and L(ρ0) = 42.8 ± 7.6 MeV, respectively. [ABSTRACT FROM AUTHOR]