PaperPanorama

Nuclear Theory·nucl-th

Wednesday·December 18, 2024

8 papers2 primary·6 cross-listed

  1. 01

    [Submitted on 15 Dec 2024]

    Radiative Capture Reaction in Cluster Effective Field Theory

    F. Nazari · M. Radin · M. Moeini Arani

    In this study, we focus on the radiative capture process of the deuteron on alpha particle leading to the formation of in the two-body formalism through the cluster effective field theory~(CEFT). It was the primitive nuclear reaction to produce in a few minutes after the Big Bang. In detail, we outline the calculation of the dominant and electromagnetic transition amplitudes of . Then, we obtain the astrophysical S-factor by fitting it to the experimental data. Finally, we compare the obtained CEFT results for the astrophysical S-factor with the other theoretical results.

    Subjects:
    Nuclear Theory (nucl-th); Solar and Stellar Astrophysics (astro-ph.SR)
    arXiv:
    2412.12205 [pdf]
    PTEP(2025)·1 citation
  2. 02

    [Submitted on 17 Dec 2024]

    Neutron Star Properties and Femtoscopic Constraints

    I. Vidana🇮🇹 · V. Mantovani Sarti🇩🇪 · J. Haidenbauer🇩🇪 · D. L. Mihaylov🇩🇪 · L. Fabbietti🇩🇪

    We construct the equation of state of hypernuclear matter and study the structure of neutron stars employing a chiral hyperon-nucleon interaction of the Jülich--Bonn group tuned to femtoscopic data of the ALICE Collaboration, and and N interactions determined from lattice QCD calculations by the HAL QCD Collaboration that reproduce the femtoscopic and data. We employ the ab-initio microscopic Brueckner--Hartree--Fock theory extended to the strange baryon sector. A special focus is put on the uncertainties of the hyperon interactions and how they are effectively propagated to the composition, equation of state, mass-radius relation and tidal deformability of neutron stars. To such end, we consider the uncertainty due to the experimental error of the femtoscopic data used to fix the chiral hyperon-nucleon interaction and the theoretical uncertainty, estimated from the residual cut-off dependence of this interaction. We find that the final maximum mass of a neutron star with hyperons is in the range , in agreement with previous works. The hyperon puzzle, therefore, remains still an open issue if only two-body hyperon-nucleon and hyperon-hyperon interactions are considered. Predictions for the tidal deformability of neutron stars with hyperons are found to be in agreement with the observational constraints from the gravitational wave event GW170817 in the mass range .

    Comments:
    10 pages, 3 figures, 3 tables. Accepted for publication in the European Journal of Physics A
    Subjects:
    Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE); Solar and Stellar Astrophysics (astro-ph.SR); High Energy Physics — Phenomenology (hep-ph)
    arXiv:
    2412.12729 [pdf]
    EPJA(2025)·25 citations
  3. 03

    [Submitted on 16 Dec 2024] (cross-list from hep-ph)

    Anisotropic jet broadening and jet shape

    Weiyao Ke🇨🇳 · John Terry🇺🇸 · Ivan Vitev🇺🇸

    In this paper, we explore the use of jet substructure as a way of probing phenomena which break the isotropic behavior of jets, such as jet propagation through an anisotropically flowing quark-gluon plasma or spin correlations. We introduce two novel observables for this purpose: the azimuthal-dependent jet broadening and the azimuthal-dependent jet shape, which generalize the traditional isotropic substructure studies. Using Soft-Collinear Effective Theory, we explicitly calculate the jet functions associated with these observables with a standard jet axis and with a Winner-Take-All jet axis in both the resummed and fixed order limits. While our analysis first and foremost establishes the formalism for the azimuthal-dependent jet substructure, it also brings to light new results for jet substructure in the azimuthally integrated case, such as the semi-inclusive jet function and the exclusive jet shape for the Winner-Take-All axis, and the jet broadening in the fixed order region. As an illustrative example for the new formalism we demonstrate that the azimuthal-dependent jet broadening can be used as a direct probe of the transversity parton distribution function in deep inelastic scattering.

    Comments:
    59 pages, 9 figures
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
    arXiv:
    2412.12250 [pdf]
    JHEP(2025)·9 citations
  4. 04

    [Submitted on 16 Dec 2024] (cross-list from hep-ph)

    QCD factorization with multihadron fragmentation functions

    T. C. Rogers🇺🇸 · M. Radici🇮🇹 · A. Courtoy🇲🇽 · T. Rainaldi🇺🇸

    Important aspects of QCD factorization theorems are the properties of the objects involved that can be identified as universal. One example is that the definitions of parton densities and fragmentation functions for different types of hadrons differ only in the identity of the nonperturbative states that form the matrix elements, but are otherwise the same. This leads to independence of perturbative calculations on nonperturbative details of external states. It also lends support to interpretations of correlation functions as encapsulations of intrinsic nonperturbative properties. These characteristics have usually been presumed to still hold true in fragmentation functions even when the observed nonperturbative state is a small-mass cluster of hadrons rather than simply a single isolated hadron. However, the multidifferential aspect of cross sections that rely on these latter types of fragmentation functions complicates the treatment of kinematical approximations in factorization derivations. That has led to recent claims that the operator definitions for fragmentation functions need to be modified from the single hadron case with nonuniversal prefactors. With such concerns as our motivation, we retrace the steps for factorizing the unpolarized semi-inclusive annihilation cross section and confirm that they do apply without modification to the case of a small-mass multihadron observed in the final state. In particular, we verify that the standard operator definition from single hadron fragmentation, with its usual prefactor, remains equally valid for the small-mass -hadron case with the same hard parts and evolution kernels, whereas the more recently proposed definitions with nonuniversal prefactors do not. Our results reaffirm the reliability of most past phenomenological applications of dihadron fragmentation functions.

    Comments:
    32 pages, 7 figures
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
    arXiv:
    2412.12282 [pdf]
    PRD(2025)·18 citations
  5. 05

    [Submitted on 16 Dec 2024] (cross-list from hep-th)

    Exact charged and rotating toroidal black hole in the Einstein -Skyrme model

    Carla Henríquez-Baez🇨🇱 · Marcela Lagos🇨🇱 · Evelyn Rodríguez🇨🇱 · Aldo Vera🇨🇱

    In this paper, we construct an exact solution of the Einstein -Skyrme model in space-time dimensions describing a charged and rotating black hole with toroidal horizon. Rotation is added by applying an improper coordinate transformation to the known static toroidal black hole with Skyrme hair, while the electric charge is supplemented by considering a gauge field interacting with Einstein gravity. We perform the thermal analysis in the grand canonical ensemble, explicitly showing the role that the flavor number plays. Some discussions about stability are also considered.

    Comments:
    12 pages, 1 figure
    Subjects:
    High Energy Physics — Theory (hep-th); General Relativity and Quantum Cosmology (gr-qc); Nuclear Theory (nucl-th)
    arXiv:
    2412.12343 [pdf]
    PRD(2025)·4 citations
  6. 06

    [Submitted on 17 Dec 2024] (cross-list from hep-ph)

    Light-by-light scattering in ultraperipheral heavy ion collisions -- new possibilities

    Antoni Szczurek🇵🇱 · Pawel Jucha🇵🇱

    Light-by-light scattering is a relatively new area of experimental physics. Our recent, theoretical research shows that studying two photon measurements in regions with lower transverse momentum () and invariant mass () allows us to observe not only the main contribution of photon scattering, known as fermionic loops but also mechanisms like the VDM-Regge (double-photon hadronic fluctuation). In addition, diphoton measurements at low diphoton masses are crucial for studies of light meson resonance contributions in scattering. We also focus on the interference between different contributions. For future experiments with the ALICE FoCal and ALICE-3 detectors, we have calculated background contamination and have explored possibilities to minimize their impact.

    Comments:
    9 pages, 8 figures, a talk given by A. Szczurek at the Zakopane 2024 Conference on Nuclear Physics, Zakopane, Poland, August 2024
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
    arXiv:
    2412.12695 [pdf]
    Acta Phys.Polon.Supp.(2025)·0 citations
  7. 07

    [Submitted on 17 Dec 2024] (cross-list from hep-ph)

    Constraining the three-body bound state via the pole

    Hai-Xiang Zhu🇨🇳 · Lu Meng🇩🇪 · Yao Ma🇨🇳 · Ning Li🇨🇳 · Wei Chen🇨🇳 · Shi-Lin Zhu🇨🇳

    In this study, we propose using the pole position to constrain the existence of the three-body bound state within the one-boson-exchange (OBE) model. The existence of the bound state remains uncertain due to significant variations in the OBE interaction, particularly in the strength of scalar-meson-exchange interactions, which can differ by a factor about 20 between two commonly used OBE models. This discrepancy renders the system highly model-dependent. To address this issue, we constrain the scalar-meson-exchange interaction using the pole position, where the pseudoscalar-meson coupling is well-determined, and the - and -exchange interactions nearly cancel each other out, leaving the coupling constant of the -exchange as the only unknown parameter. Our results indicate that the isospin- bound states exist when is a virtual state of located within approximately MeV of the threshold. However, the three-body bound state is gone when the virtual state pole is more than MeV away from the threshold. Each experimental progress, either on the state or the , can shed light on the nature of the other state. Another significant outcome is a refined set of OBE model parameters calibrated using the pole positions of , , and , rigorously addressing the cutoff dependence. These parameters provide a valuable resource for more accurate calculations of systems involving few-body , and their antiparticles. Additionally, we find no evidence of the three-body resonances after extensive search using a combination of the Gaussian expansion method and the complex scaling method.

    Comments:
    16 pages,8 figures;Accepted for publication in PRD
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
    arXiv:
    2412.12816 [pdf]
    PRD(2025)·14 citations
  8. 08

    [Submitted on 17 Dec 2024] (cross-list from hep-ph)

    Chirally motivated - model in a finite volume

    Peter C. Bruns🇨🇿 · Ales Cieply🇨🇿

    We generalize the chirally motivated coupled channels model to the cubic finite volume and use it to calculate the stationary energy spectrum that appears in a nice agreement with the spectrum obtained in the lattice QCD simulations by the BaSc collaboration. Several other comparisons with the BaSc results are made, in particular relating their pole positions of the meson-baryon scattering matrix to the two-pole picture of generated by our chiral model in the infinite volume.

    Comments:
    10 pages, 4 figures; updated to match the published version
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
    arXiv:
    2412.12977 [pdf]
    EPJA(2025)·2 citations

Affiliations

first authorsco-authorsvia INSPIRE