PaperPanorama

Nuclear Theory·nucl-th

Wednesday·November 5, 2025

6 papers—3 primary·3 cross-listed

All6Primary3Cross-lists3
  1. 01

    General relativistic study of -mode oscillations in neutron stars with gravitationally bound dark matter

    Pinku Routaray🇮🇳

    A comprehensive investigation of nonradial oscillations in neutron star (NS) admixed with gravitationally bounded dark matter (DM) is carried out within the framework of full general relativity. The relativistic mean field (RMF) formalism is employed to illustrate the hadronic equation of state (EOS), while a physically motivated, gravitationally captured, non-uniform fermionic Higgs-portal DM component is incorporated to model DM-admixed NS. The DM distribution is characterized by two free parameters: , an effective control parameter that combines the DM concentration and the DM candidate mass, and , a steepness parameter controlling the DM density distribution. The quasi normal mode (QNM) characteristics such as fundamental () mode frequency and its corresponding gravitational-wave (GW) damping time () is calculated for DM-admixed NS by solving the general relativistic perturbed equations involving axial as well as polar modes. The study demonstrates how the inclusion of DM distribution modifies the -mode frequency and enhances the damping rate, reflecting a stronger coupling between matter and spacetime perturbations. Considering DM effects, the correlation analysis among DM model parameters, NS observables and QNM characteristics also carried out. Analytic fits for the and relations are constructed and calibrated for DM-admixed NS models. Building upon asteroseismic universal relations (URs), multimessenger constraint from the GW170817 event is employed by mapping the tidal deformability into the space, thereby providing observational bounds on the oscillation properties of canonical DM-admixed NS model.

    nucl-thastro-ph.HEgr-qcPhys.Dark Univ.(2026)·3 citations
  2. 02

    Revisiting the three-kaon interaction and its relation with

    Michael Döring🇺🇸 · Kanchan P. Khemchandani🇧🇷 · Alberto Martínez Torres🇧🇷

    We test the hypothesis of being a hadronic molecule through nonperturbative -wave , , coupled-channel dynamics in a three-body unitary isobar approach. The scalar two-body coupled-channel resonances , , and are generated in the subsytems in amplitudes that match phase shifts from experiment. In a first step, previous results in the limit of mass-degenerate, stable and isobars are reproduced. Once the full seven-coupled channel model is switched on, other -matrix effects obscure and modify the resonance signal, including complex thresholds, a two-body cusp, and a triangle singularity at threshold.

    nucl-thhep-phnucl-exPRD(2026)·5 citations
  3. 03

    A Bayesian Inference of Hybrid Stars with Large Quark Cores

    Milena Albino🇵🇹 · Tuhin Malik🇵🇹 · Márcio Ferreira🇵🇹 · Constança Providência🇵🇹

    Neutron stars (NSs) are interesting objects capable of reaching densities unattainable on Earth. The properties of matter under these conditions remain a mystery. Exotic matter, including quark matter, may be present in the NS core. In this work, we explore the possible compositions of NS cores, in particular, the possible existence of large quark cores. We use the Relativistic Mean Field (RMF) model with nonlinear terms for the hadron phase and the Nambu-Jona-Lasinio (NJL) model and Mean Field Theory of Quantum Chromodynamics (MFTQCD) for the quark phase. Through Bayesian inference, we obtain different sets of equations: four sets with hybrid equations and one set with only the hadron phase. We impose constraints regarding the properties of nuclear matter, X-ray observational data from NICER, gravitational wave data from the binary neutron star merger GW170817, perturbative QCD (pQCD) calculations, and causality. The MFTQCD allows for a phase transition to quark matter at low densities, just above saturation density, while for the NJL sets, the phase transition occurs above twice the saturation density. As a result, the MFTQCD model predicts the presence of quark matter in the inner core of 1.4 M NSs, while NJL models suggest a low probability of quark matter in the interior of a 1.4 M NS. Both models predict the existence of quark matter in 2 M NSs. The slope of the mass-radius curve has been shown to carry information about the presence of quark matter. In particular, a positive slope at 1.8 M indicates the presence of non-nucleonic matter. A hybrid star with a stiff quark equation of state could explain a larger radius in more massive stars, such as two solar mass stars, compared to canonical NSs.

    nucl-thastro-ph.HEgr-qchep-phPRD(2026)·13 citations
  4. 04

    Entanglement asymmetry in gauge theories: chiral anomaly in the finite temperature massless Schwinger model

    Adrien Florio🇩🇪 · Sara Murciano🇫🇷

    The entanglement asymmetry has emerged in recent years as a practical quantity to study phases of matter. We present the first study of entanglement asymmetry in gauge theories by considering the chiral anomaly of the analytically solvable massless Schwinger model at both zero and finite temperatures. At zero temperature, we find the asymmetry exhibits logarithmic growth with system size. At finite temperature, we show that it is parametrically more sensitive to chiral symmetry-breaking than the corresponding local order parameter: while the chiral condensate decays exponentially, the asymmetry decreases only logarithmically. This establishes the entanglement asymmetry as a promising tool to probe (finite-temperature) phase transitions in gauge theories.

    ↳ hep-thcond-mat.stat-mechhep-phnucl-th+1PRD(2026)·11 citations
  5. 05

    Incoherent Particle Production in Ultraperipheral Heavy Ion Collisions

    L. A. Harland-Lang🇬🇧

    In this paper, we present the first complete treatment of incoherent photon-initiated production in ultraperipheral heavy ion collisions, focussing on the dilepton and diphoton final states. In the former case we compare to the ATLAS measurement of dielectron production and find that our predictions match the data very well. In the latter case we show that this contribution is too small to explain the observed broad in diphoton acoplanarity background to the purely coherent light-by-light scattering signal. We in addition consider a new `quark emission' topology, which while naively might be expected to dominate the incoherent diphoton production channel, is in fact found to be kinematically suppressed. Finally, we revisit QCD-initiated diphoton production and issue of theoretical uncertainties in this case. We find that this again cannot explain the observed size of the higher acoplanarity background. The production mechanism leading to this background to light-by-light production, and the reason for its observed enhancement in comparison to the dilepton case, therefore remains unclear.

    ↳ hep-phhep-exnucl-exnucl-thPRD(2026)·0 citations
  6. 06

    Magnetic-type Love number differentiating quark stars from neutron stars

    Kenji Fukushima🇯🇵 · Josuke Minamiguchi🇯🇵 · Tomoya Uji🇯🇵

    The quark star (QS) is a hypothetical and yet undiscovered stellar object, and its existence would mark a paradigm shift in research on nuclear and quark matter. Although compactness is a well-known signature for distinguishing between two branches of QSs and neutron stars (NSs), some QSs can overlap with NSs in the radius-mass plane. To manifest their evident differences, we investigate the tidal properties of QSs and NSs. We then find that the magnetic-type Love number is a robust indicator for differentiating between QSs and NSs, whereas the electric-type one is insufficient when QSs and NSs have similar masses and radii. Finally, we show that gravitational waves from binary star mergers can be sensitive to differences between QSs and NSs to the detectable level.

    ↳ astro-ph.HEnucl-th1 citation

Affiliations

first authorsco-authorsvia INSPIRE