PaperPanorama

Nuclear Theory·nucl-th

Monday·September 29, 2025

6 papers3 primary·3 cross-listed

  1. 01

    [Submitted on 25 Sept 2025]

    Neutron Skin from Conserved Charge Measurements at Collider Experiments

    Grégoire Pihan🇺🇸 · Akihiko Monnai🇯🇵 · Björn Schenke🇺🇸 · Chun Shen🇺🇸

    We propose a novel method for measuring the neutron skin of heavy nuclei using collider experiments. Specifically, we demonstrate that the neutron skin thickness of the lead nucleus can be extracted in +Pb collisions by analyzing a double ratio: The ratio of net electric charge to net baryon number measured near the lead-going rapidity, taken for high-multiplicity events and divided by the same ratio for low-multiplicity events. We compute the expected sensitivity of the double ratio to the neutron skin within a comprehensive (3+1)D relativistic hydrodynamic framework that incorporates multiple conserved charge currents and a charge-dependent lattice-QCD-based equation of state. We provide predictions for both +Pb collisions at ~GeV and ~TeV, corresponding to the center of mass energies realized in the SMOG2 fixed-target setup at LHCb and the LHC collider mode, respectively.

    Comments:
    6 pages, 3 figures
    Subjects:
    Nuclear Theory (nucl-th)
    arXiv:
    2509.21644 [pdf]
    7 citations
  2. 02

    [Submitted on 26 Sept 2025]

    Isoenergetic description of induced fission pathways within energy-density functional theory

    Alan A. Dzhioev · N. V. Antonenko

    A thermodynamically consistent description of induced fission pathways in the superheavy nucleus Lv is presented within the framework of nuclear energy-density functional theory. Using self-consistent finite-temperature Hartree-Fock-Bogoliubov calculations with the Skyrme-type energy-density functional SkM, we derive and compare effective potentials corresponding to different thermodynamic processes -- isothermal (), isentropic (), and isoenergetic () -- as functions of quadrupole deformation and excitation energy. At the same amount of excitation energy the isoenergetic description predicts the highest fission barrier and the largest damping factor. The suppression of the isoenergetic fission barrier is analyzed by examining how the driving force changes with increasing excitation energy and by studying the contribution of the nonpotential term to the effective potential. Within the framework of the three thermodynamic schemes considered, the different behavior of temperature and entropy along the fission pathway is also emphasized. A transition of the effective level-density parameter from a deformation-sensitive quantity at low excitation energies to a nearly constant value at high energies is observed, in line with the Fermi-gas model expectations.

    Subjects:
    Nuclear Theory (nucl-th)
    arXiv:
    2509.22006 [pdf]
    PRC(2025)·0 citations
  3. 03

    [Submitted on 26 Sept 2025]

    Cumulative proton production in collisions

    A.B. Larionov🇷🇺

    The model of backward proton production in the exclusive reaction at proton beam momenta up to several GeV/c is constructed on the basis of Feynman diagrams for one- and two-step amplitudes. The latter include nucleon and resonance intermediate scattering states with propagators reduced to eikonal form using the generalized eikonal approximation. The model calculations are compared with available experimental data on the energy spectra of protons at backward polar angles in the deuteron rest frame. It is shown that inclusion of two-step amplitudes significantly increases the production of backward protons with energies above 50 MeV, thereby significantly improving the agreement with experiment. The remaining theoretical problem related to the description of the off-shell behavior of the elementary amplitudes of the and transitions is discussed. Partial discrepancies between different sets of experimental data do not allow for conclusion that exotic effects, such as proton interactions with density fluctuations and/or clusters in the deuteron, are present.

    Comments:
    35 pages, 16 figures, discussion extended, conclusions unchanged, version accepted in Phys. Rev. C
    Subjects:
    Nuclear Theory (nucl-th); High Energy Physics — Experiment (hep-ex); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
    arXiv:
    2509.22433 [pdf]
    PRC(2026)·1 citation

Affiliations

first authorsco-authorsvia INSPIRE