PaperPanorama
FAQ

Nuclear Theory·nucl-th

Monday·December 19, 2022

10 papers—4 primary·6 cross-listed

All10Primary4Cross-lists6
  1. 01

    [Submitted on 15 Dec 2022]

    Muon capture on the deuteron in chiral effective field theory

    Jose Bonilla🇺🇸 · Bijaya Acharya🇺🇸 · Lucas Platter🇺🇸

    We consider the capture of a muon on a deuteron. An uncertainty analysis of the dominant channels is important for a careful analysis of forthcoming experimental data. We quantify the theoretical uncertainties of chiral effective-field-theory predictions of the muon-deuteron capture rate from the relevant neutron-neutron partial wave channels in the final state. We study the dependence on the cutoff used to regularize the interactions, low-energy constants calibrated using different fitting data and strategies, and truncation of the effective-field-theory expansion of the currents. Combining these approaches gives as an estimate of s for capture from the atomic doublet state, and s for capture from the quartet state.

    Comments:
    17 pages, 3 figures
    Subjects:
    Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
    arXiv:
    2212.08138 [pdf]
    PRC(2023)·4 citations
  2. 02

    [Submitted on 16 Dec 2022]

    Speed of sound and liquid-gas phase transition in nuclear matter

    Wei-bo He🇨🇳 · Guo-yun Shao🇨🇳 · Chong-long Xie🇨🇳

    We investigate the speed of sound in nuclear matter at finite temperature and density~(chemical potential) in the nonlinear Walecka model. The numerical results suggest that the behaviors of sound speed are closely related to the the nuclear liquid-gas (LG) phase transition and the associated spinodal structure. The adiabatic sound speed is nonzero at the critical endpoint (CEP) in the mean field approximation. We further derive the boundary of vanishing sound velocity in the temperature-density phase diagram, and point out the region where the sound wave equation is broken. The distinction between the speed of sound in nuclear matter and that in quark matter contains important information about the equation of state of strongly interacting matter at intermediate and high density. We also formulate the relations between differently defined speed of sound using the fundamental thermodynamic relations.

    Comments:
    11pages, 16 figures
    Subjects:
    Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
    arXiv:
    2212.08263 [pdf]
    PRC(2023)·20 citations
  3. 03

    [Submitted on 16 Dec 2022]

    The proxy-SU(3) symmetry in atomic nuclei

    Dennis Bonatsos · Andriana Martinou · S.K. Peroulis · T.J. Mertzimekis · N. Minkov

    The microscopic origins and the up-to-now predictions of the proxy-SU(3) symmetry model of atomic nuclei are reviewed. Starting from the experimental evidence for the special role played by nucleon pairs with maximal spatial overlap, the proxy-SU(3) approximation scheme is introduced and its validity is demonstrated through Nilsson model calculations, as well as through its connection to the spherical shell model. The major role played by highest weight irreducible representations of SU(3) in shaping up the nuclear properties is pointed out, resulting in parameter-free predictions of the collective variables beta and gamma for even-even nuclei, in the explanation of the dominance of prolate over oblate shapes in the ground states of even-even nuclei, in the prediction of a shape/phase transition from prolate to oblate shapes below closed shells, as well as in the prediction of specific islands on the nuclear chart in which shape coexistence is confined. Further developments within the proxy-SU(3) scheme are outlined.

    Comments:
    27 pages, 9 figures, 8 tables
    Subjects:
    Nuclear Theory (nucl-th)
    arXiv:
    2212.08494 [pdf]
    Symmetry(2023)·34 citations
  4. 04

    [Submitted on 16 Dec 2022]

    Fock space representations of Bogolyubov transformations as spin representations

    K. Neergård

    The representation on a Fock space of the group of Bogolyubov transformations is recognized as the spin representation of an orthogonal group. Derivations based on this observation of some known formulas for the overlap amplitude of two Bogolyubov quasi-fermion vacuum states that are in some cases more complete than those in the literature are shown. It is pointed out that the name of an "Onishi formula" is assigned in the literature to two different expressions which are related but have different scopes. One of them has what has been described as a sign problem, the other one, due to Onishi and Yoshida, has a more limited scope and no sign problem. I give a short proof of the latter, whose derivation is missing in the paper by Onishi and Yoshida, and a new, combinatoric, proof of an equivalent formula recently derived by Robledo.

    Subjects:
    Nuclear Theory (nucl-th)
    arXiv:
    2212.08598 [pdf]
    PRC(2023)·3 citations

Affiliations

first authorsco-authorsvia INSPIRE