Nuclear Theory·nucl-th

Wednesday·May 13, 2026

13 papers—5 primary·8 cross-listed

01
The mean-field theory of superfluid-superconducting vortex states in the outer core of neutron stars
Dmitry Kobyakov
Purpose: Characterize superfluid-superconducting vortex states at arbitrary pressures with $T_{c p} \neq = T_{c n}$ , assuming both proton and neutron mean-fields are formed by spin-0 Cooper pairs. Method: The existing mean-field theory is extended to account for $T_{c p} \neq = T_{c n}$ . The pressure dependence of the pairing gap energy $Δ_{α 0}$ is quantitatively established on the basis of the effective chiral field theory. To link $T_{c α}$ with $Δ_{α 0}$ , I use the weak-coupling result $T_{c α} \approx 0.57 Δ_{α 0}$ . A quadratic scaled-temperature ( $T / T_{c p}$ ) dependence of the thermodynamic magnetic field is postulated in analogy with pure superconductors. The $T / T_{c α}$ -dependence of the gap $Δ_{α T}$ is inferred from the many-body approximations for the pure neutron matter. Results: An empirical $T / T_{c α}$ -dependence for the mean-field is constructed to account for the interplay between the condensation and the magnetic energies. The superfluid entrainment is found to increase the size of the vortex core and to decrease the effective magnetic penetration depth. The size of the neutron vortex core is found to be larger than the magnetic penetration depth in the outer core. Conclusions: The usual approximation of infinitely thin vortex line (the London's approximation) for the neutron vortex is found to be irrelevant in the entire outer core and for the proton vortex is found to be limited to vicinity of the crust-core transition. The developed mean-field theory paves the way to study the vortex microscopic structure, the angular momentum, the magnetization and the vortex-fluxtube interaction energy.
nucl-thastro-ph.SRcond-mat.supr-con0 citations
02
Rigorous proof of the Strutinsky energy theorem and foundations of nuclear density functional theory
Chong Qi
We have derived a rigorous theoretical proof of the Strutinsky energy theorem. This proof not only provides a proper interpretation of the shell-correction decomposition, resolving decades of confusion, but also lays a foundation for constructing nuclear density functionals.
nucl-th0 citations
03
Freeze-out model of light nuclei formation in heavy-ion collision transport
Oleh Savchuk🇺🇸 · Pawel Danielewicz🇺🇸 · William Lynch🇺🇸 · Jérôme Margueron🇺🇸
Cluster production plays an important role in heavy-ion collisions at intermediate beam energies, where light nuclei contribute substantially to final-state yields and to other observables that are used to infer the nuclear equation of state. In this letter, we propose a new approach for clustering that combines dynamical transport and thermal cluster production for mid-rapidity particles. The resulting hybrid coarse-graining model matches nucleon and light-cluster descriptions at freeze-out while properly accounting for thermal non-uniformity and collective transport in the hot, strongly interacting systems created in heavy-ion collisions. To illustrate the capabilities of this model, yields at 4~fm impact parameter, spectra and elliptic flows at 7.4~fm ( $20 - 30%$ centrality) are predicted at mid-rapidity for semi-peripheral Au $+$ Au collisions at an incident energy of $E_{lab} = 1.23 A GeV$ .
nucl-th0 citations
04
Ab initio calculation of symmetry-breaking observables
A Belley · B. Romeo · J. Engel · D. Kekejian · T. Miyagi · S. Foster · P. Navratil · B. C. He · S. R. Stroberg · J. D. Holt · R. F. Garcia Ruiz
Symmetry-violating observables such as the nuclear anapole and Schiff moments provide sensitive probes of the fundamental symmetries of nature and physics beyond the Standard Model. Their interpretation has been hindered, however, by the lack of ab initio nuclear structure calculations in the medium-mass and heavy nuclei of interest to experimentalists. To provide them, we introduce a new version of the in-medium similarity renormalization group (IMSRG) designed to target parity-violating operators. By generalizing the IMSRG flow equations to evolve the weak symmetry-breaking Hamiltonian - and the anapole or Schiff operators - alongside the strong nuclear Hamiltonian, we construct a systematically improvable framework for computing these parity-violating moments. We benchmark the method against the no-core shell model in light nuclei and obtain the first ab initio predictions of the anapole moment in $^{29}$ Si and the Schiff moments in $^{129}$ Xe. These heavier systems are of direct experimental interest.
nucl-thnucl-ex4 citations
05
Mass radius and D-term of atomic nuclei in relativistic mean field theory
Yoshitaka Hatta · Tomohiro Oishi · Makoto Oka
Based on relativistic mean field theory for atomic nuclei, we compute the mass radius and other radii associated with the energy momentum tensor for dozens of spin-0 nuclei across the nuclear chart. We also compute the D-term of these nuclei, the forward limit of the gravitational form factor $D (t = 0) = D$ . The dependence on the neutron number $N$ is systematically studied for calcium (Ca), nickel (Ni), zirconium (Zr), tin (Sn) and lead (Pb) isotopes. Remarkably, $∣ D ∣$ does not monotonically increase with $N$ . Instead, it exhibits local maxima and minima when $N$ equals a magic number and even a sub-magic number. This results in characteristic kinks in the mass, scalar, tensor and shear radii of these isotopes. Our work for the first time elucidates the strong sensitivity of the various mechanical properties of nuclei to the nuclear shell structure.
nucl-thhep-phPRC(2026)·1 citation

Affiliations

first authorsco-authorsvia INSPIRE

The mean-field theory of superfluid-superconducting vortex states in the outer core of neutron stars

Rigorous proof of the Strutinsky energy theorem and foundations of nuclear density functional theory

Freeze-out model of light nuclei formation in heavy-ion collision transport

Ab initio calculation of symmetry-breaking observables

Mass radius and D-term of atomic nuclei in relativistic mean field theory

Affiliations