PaperPanorama
FAQ

Nuclear Theory·nucl-th

Monday·March 2, 2026

7 papers—5 primary·2 cross-listed

All7Primary5Cross-lists2
  1. 01

    Hyperon-Induced Inhomogeneous Pion Condensation and Moat Regimes in Neutron Star Cores

    Theo F. Motta🇧🇷 · Randall H. V. Pradinett🇧🇷 · Gastão Krein🇧🇷

    We perform a stability analysis of the homogeneous ground state of nuclear matter against inhomogeneous perturbations of the pion condensate. In -equilibrium, restricting the baryon species to nucleons only, we observe no instability; however, at high densities, the pseudoscalar density-density correlations assume a moat regime, i.e. a damped oscillatory patterned spatial correlation, which in momentum space appears as a non-zero global minimum for some finite three-momentum. When hyperons are permitted to appear, this minimum can cross down to negative values, which configures an instability towards an inhomogeneous pion condensate which ultimately will affect the equation of state.

    nucl-thhep-phPRD(2026)·1 citation
  2. 02

    Particle number projected energies at finite temperature

    Jiawei Chen · Yu Qiang · Junchen Pei

    In this work, the particle number projection at finite temperature is incorporated into self-consistent Skyrme density functional calculations. In particular, the energies of compound nuclei as a function of deformations are calculated rigorously based on projected densities. Results show that the even-odd staggering effect in partition function gradually diminishes as the system approaches the critical temperature. The obtained fission barriers are similar to that without projection at finite temperature, although projected energies are different. The nuclear level density at the ground state and the barrier are also studied using the projection method and the discrete Gaussian method.

    nucl-thPRC(2026)·0 citations
  3. 03

    Is nucleon spin thermalized in intermediate-energy heavy-ion collisions?

    Jun Xu🇨🇳

    Despite the success of the spin-thermalized assumption in explaining hyperon spin polarizations in relativistic heavy-ion collisions, challenges begin to arise especially at lower collision energies. The present study compares the nucleon spin polarization during the collision process and at the freeze-out stage from a non-relativistic spin-dependent transport model with spin-thermalized approaches in intermediate-energy heavy-ion collisions, where the relativistic effect and the temperature gradient have shown to be unimportant. It is found that both the global and local spin polarizations are largely overestimated from spin-thermalized approaches, compared to those generated by the spin-orbit mean-field potential in transport simulations.

    nucl-thnucl-exAPS Open Science(2026)·1 citation
  4. 04

    factor of C(,)O at low energies in cluster effective field theory

    Shung-Ichi Ando

    The C(,)O reaction at low energies is studied by constructing an effective field theory. We choose a separation scale at ~MeV, where is the initial -C energy in center-of-mass frame, just below the sharp resonant state of O, and include two open channels, -C and -O, and resonant , , states of O in the study. Parameters of the theory are fitted to experimental data, factor of C(,)O at the energies below ~MeV, including the data sets recently reported by the LUNA and JUNA collaborations, and the factor of C(,)O is extrapolated to the Gamow peak energy ~MeV in the low mass AGB stars. We discuss an uncertainty in the estimate of the factor and confirm that the main part of the uncertainty emerges from the parameter fit of the near-breakup threshold state of O.

    nucl-thhep-phnucl-ex1 citation
  5. 05

    Theoretical Studies of alpha Clustering in Nuclei and Beyond

    Takaharu Otsuka · Alexander Volya · Naoyuki Itagaki

    This article comprises three sections. Section 2 starts with a review of ab initio no-core shell model calculations by Monte Carlo Shell Model. Alpha clustering arises for 8,10,12Be and 12C with Daejeon16 and JISP16 interactions, even in the ground state of 12C. Hoyle state is shown to be dominated by alpha clustering in triangular configurations. As the ground and Hoyle states show strong deformations, they are good cases to investigate rotational excitations. As an original work, the recently proposed fully quantum (mechanical) formulation for deformation and rotation is extended to cluster states. Dual rotational modes are proposed: compact-object and distant-object rotations. The former is found in many heavy nuclei, whereas the latter can be found for clustering states. While 8Be is an example for the latter, 12C is a rare example that both modes appear. Atomic molecules and hadrons can be viewed similarly. Possible relevance to fission is mentioned. Section 3 presents a general framework for an extended no-core shell model with cluster-nucleon configuration interaction, combining traditional shell-model-like configurations with explicit microscopic configurations representing cluster degrees of freedom. The section reviews the microscopic origins of cluster substructures in light nuclei, emphasizing how nucleonic degrees of freedom, nucleon-nucleon interactions, and continuum coupling naturally extend the traditional shell model into configuration-interaction frameworks that incorporate clustering and reaction dynamics. Section 4 presents that although the cluster structure is robust in Be-C nuclei, some jj-coupling shell model components are mixed in the ground state of 12C. Using the antisymmetrized quasi cluster model, we can clearly model this competition between the cluster and shell components. The spin-orbit interaction is key.

    nucl-thnucl-exEPJA(2026)·1 citation

Affiliations

first authorsco-authorsvia INSPIRE