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Nuclear Theory·nucl-th

Friday·October 21, 2022

6 papers—2 primary·4 cross-listed

All6Primary2Cross-lists4
  1. 01

    Nuclear Equation of State and Single-nucleon Potential from Gogny-like Energy Density Functionals Encapsulating Effects of Nucleon-nucleon Short-range Correlations

    Bao-Jun Cai🇨🇳 · Bao-An Li🇺🇸

    Nucleon-nucleon short-range correlations (SRCs) induce a high momentum tail (HMT) in the single-nucleon momentum distribution function in cold neutron-rich matter. While there are clear experimental evidences that the SRC/HMT effects are different for neutrons and protons and their strengths depend strongly on the isospin asymmetry of finite nuclei mostly based on electron-nucleus scattering experiments, much less is known experimentally about the SRC/HMT effects in the dense neutron-rich matter. To facilitate further explorations of SRC/HMT effects in dense neutron-rich matter especially with heavy-ion reactions involving high-energy radioactive beams as well as multimessenger observations of neutron stars and their mergers, by incorporating the SRC-induced HMT in into a Gogny-like energy density functional we study SRC/HMT effects on the equation of state (EOS) especially its symmetry energy term and single-nucleon potential in the dense asymmetric nucleonic matter (ANM). Using a parametrization as a surrogate for the momentum-dependent kernel in the Gogny-like energy density functional (EDF) we derive analytical expressions for all components of the ANM EOS and their characteristics (e.g., magnitude, slope and curvature as well as nucleon effective mass) at saturation density as well as the momentum-dependent single-nucleon optical potential in neutron-rich matter using parameters characterizing nuclear interactions as well as the size, shape and isospin dependence of the HMT at . Some consequences of the SRC/HMT effects on properties of neutron stars are also studied.

    nucl-thastro-ph.HEnucl-ex8 citations
  2. 02

    Covariant energy density functionals with and without tensor couplings at the Hartree-Bogoliubov level

    F. Mercier🇫🇷 · J.-P. Ebran🇫🇷 · E. Khan🇫🇷

    Background: The study of additional terms in functionals is relevant to better describe nuclear structure phenomenology. Among these terms, the tensor one is known to impact nuclear structure properties, especially in neutron-rich nuclei. However, its effect has not been studied on the whole nuclear chart yet. Purpose: The impact of terms corresponding to the tensor at the Hartree level, is studied for infinite nuclear matter as well as deformed nuclei, by developing new density-dependent functionals including these terms. In particular, we study in details the improvement such a term can bring to the description of specific nuclear observables. Methods: The framework of covariant energy density functional is used at the Hartree-Bogoliubov level. The free parameters of covariant functionals are optimized by combining Markov-Chain-Monte-Carlo and simplex algorithms. Results: An improvement of the RMS binding energies, spin-orbit splittings and gaps is obtained over the nuclear chart, including axially deformed ones, when including tensors terms. Small modifications of the potential energy surface and densities are also found. In infinite matter, the Dirac mass is shifted to a larger value, in better agreement with experiments. Conclusions: Taking into account additional terms corresponding to the tensor terms in the vector-isoscalar channel at the Hartree level, improves the description of nuclear properties, both in nuclei and in nuclear matter.

    nucl-thPRC(2023)·9 citations
  3. 03

    J/ yields in low energy nuclear collisions at SPS and FAIR: A baseline estimation

    S. Chatterjee🇮🇳 · P. P. Bhaduri🇮🇳 · S. Chattopadhyay🇮🇳

    The yield of mesons, produced in proton-nucleus () and nucleus-nucleus () collisions are estimated within a Glauber model ansatz for the upcoming low energy heavy-ion collision experiments at SPS and FAIR. A data driven parametrization is employed to incorporate the effects of Cold Nuclear Matter (CNM) on the production cross-section.

    ↳ hep-phnucl-thNPA(2023)·5 citations
  4. 04

    Restoring broken symmetries using oracles

    Edgar Andres Ruiz Guzman🇫🇷 · Denis Lacroix🇫🇷

    We present a new method to perform variation after projection in many-body systems on quantum computers that does not require performing explicit projection. The technique employs the notion of ``oracle'', generally used in quantum search algorithms. We show how to construct the oracle and the projector associated with a symmetry operator. The procedure is illustrated for the parity, particle number, and total spin symmetries. The oracle is used to restore symmetry by indirect measurements using a single ancillary qubit. An Illustration of the technique is made to obtain the approximate ground state energy for the pairing model Hamiltonian.

    ↳ quant-phcond-mat.str-elnucl-thPRC(2023)·17 citations
  5. 05

    Pomeron and Reggeon contributions to elastic proton-proton and proton-antiproton scattering in holographic QCD

    Zhibo Liu🇨🇳 · Wei Xie🇨🇳 · Akira Watanabe🇨🇳

    The total and differential cross sections of elastic proton-proton and proton-antiproton scattering are studied in a holographic QCD model, considering the Pomeron and Reggeon exchanges in the Regge regime. In our model setup, the Pomeron and Reggeon exchanges are described by the Reggeized spin-2 glueball and vector meson propagators, respectively. How those contributions change with the energy is explicitly shown, focusing on the contribution ratios. The adjustable parameters included in the model are determined with the experimental data, and it is presented that the resulting total and differential cross sections are consistent with the data in a wide kinematic region.

    ↳ hep-phhep-exnucl-exnucl-thPRD(2023)·13 citations
  6. 06

    Measured proton electromagnetic structure deviates from theoretical predictions

    R. Li🇺🇸 · N. Sparveris🇺🇸 · H. Atac🇺🇸 · M. K. Jones🇺🇸 · M. Paolone🇺🇸 · Z. Akbar🇺🇸 · C. Ayerbe Gayoso🇺🇸 · V. Berdnikov🇺🇸 · D. Biswas🇺🇸 · M. Boer🇺🇸 · A. Camsonne🇺🇸 · J.-P. Chen🇺🇸 and 35 other authors

    The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state.A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades. Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.

    ↳ nucl-exnucl-thNature(2022)·12 citations

Affiliations

first authorsco-authorsvia INSPIRE