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Nuclear Theory·nucl-th

Thursday·May 11, 2023

7 papers—3 primary·4 cross-listed

All7Primary3Cross-lists4
  1. 01

    CREX- and PREX-II-motivated relativistic interactions and their implications for the bulk properties of nuclear matter and neutron stars

    Mukul Kumar🇮🇳 · Sunil Kumar🇮🇳 · Virender Thakur🇮🇳 · Raj Kumar🇮🇳 · B. K. Agrawal🇮🇳 · Shashi K. Dhiman🇮🇳

    We investigate the implications of parity-violating electron scattering experiment on neutron skin thickness of Ca (CREX) and Pb (PREX-II) data on the bulk properties of finite nuclei, nuclear matter, and neutron stars. The neutron skin thickness from the CREX and PREX-II data is employed to constrain the parameters of relativistic mean field models which includes different non-linear, self and cross-couplings among isoscalar-scalar , isoscalar-vector , isovector-scalar and isovector-vector meson fields up to the quartic order. Three parametrizations of RMF model are proposed by fitting CREX, PREX-II and both CREX as well as PREX-II data to assess their implications. A covariance analysis is performed to assess the theoretical uncertainties of model parameters and nuclear matter observables along with correlations among them. The RMF model parametrization obtained with the CREX data acquires much smaller value of symmetry energy (J= 28.97 0.99 MeV), its slope parameter (L= 30.61 MeV) in comparison to those obtained with PREX-II data. The neutron star properties are studied by employing the equations of state (EoSs) composed of nucleons and leptons in equilibrium.

    nucl-thastro-ph.HEPRC(2023)·35 citations
  2. 02

    Constraining the chirally motivated - models with the photoproduction mass spectra

    A. Cieply🇨🇿 · P. C. Bruns🇨🇿

    The paper presents a first time attempt on a combined fit of the low-energy data and the photoproduction mass spectra, performed without fixing the meson-baryon rescattering amplitudes to a specific coupled channels model obtained from fitting exclusively the data. The formalism adopted to describe the photoproduction process is based on chiral perturbation theory and employs a limited number of free parameters. The achieved description of the photoproduction mass distributions is not quite satisfactory, leaving a room for improving the photo-kernel construction, but still provides additional constraints on the positions of the poles. In particular, the presented models tend to limit the mass of the lower pole and yield a larger width of the related pole at a higher mass.

    nucl-thhep-phNPA(2024)·4 citations
  3. 03

    Constraint of pionless EFT using two-nucleon spectra from lattice QCD

    William Detmold🇺🇸 · Fernando Romero-López🇺🇸 · Phiala E. Shanahan🇺🇸

    Finite-volume pionless effective field theory (FVEFT) at next-to-leading order (NLO) is used to analyze the two-nucleon lattice QCD spectrum of Ref.~\cite{Amarasinghe:2021lqa}, performed at quark masses corresponding to a pion mass of approximately MeV. Specifically, the effective theory is formulated in finite volume, and variational sets of wave functions are optimized using differential programming. Using these wave functions projected to the appropriate finite-volume symmetry group, variational bounds from FVEFT are obtained for the ground state, as well as excited states. By comparison with the lattice QCD GEVP spectrum, different low energy constants (LECs) are constrained. Relativistic corrections are incorporated, allowing for the extractions of NLO LECs, as well as the leading --wave mixing term in the deuteron channel.

    nucl-thhep-lathep-phPRD(2023)·6 citations
  4. 04

    What if theory in 4 dimensions is non-trivial in the continuum?

    Paul Romatschke🇺🇸

    Traditionally, scalar theory in four dimensions is thought to be quantum trivial in the continuum. This tradition is apparently well grounded both in physics arguments and mathematical proofs. Digging into the proofs one finds that they do not actually cover all physically meaningful situations, in particular the case of multi-component fields and non-polynomial action. In this work, I study multi-component scalar field theories in four dimensions in the continuum and show that they do evade the apparently foregone conclusion of triviality. Instead, one finds a non-trivial interacting theory that has two phases, bound states and non-trivial scattering amplitudes in the limit of many components. This has potentially broad implications, both for the foundations of quantum field theory as well as for the experimentally accessible Higgs sector of the Standard Model.

    ↳ hep-thhep-phnucl-thPLB(2023)·35 citations
  5. 05

    Non-linear chiral magnetic waves

    Kazuki Ikeda🇺🇸 · Dmitri E. Kharzeev🇺🇸 · Shuzhe Shi🇺🇸

    The chiral magnetic wave (CMW) is a macroscopic quantum phenomenon that arises due to the mixing of the electric and chiral charge oscillations induced by the chiral anomaly. In this study we report the first quantum simulation (on classical hardware) of the real-time dynamics of CMWs in Schwinger model. Our quench protocol is the following: at we suddenly place an electric dipole at the middle of our lattice. Due to chiral anomaly, this dipole excites the CMW that propagates towards the edges of the lattice. In Schwinger model tuned to the conformal critical point (at , ), we find a gapless linear CMW that propagates with the speed of light. For massless Schwinger model (), we find a gapped linear CMW, in accord with previous analytical analyses. For massive Schwinger model (that is dual to strongly interacting bosonic theory), we enter the new regime of nonlinear CMWs, where we find a surprise. Specifically, for , the frequency of electric charge oscillations becomes much smaller than the frequency of the oscillations of the chiral charge. For , we find a solution corresponding to a nearly static electric dipole with fast oscillations of the chiral charge confined within. We call this solution a "thumper" and study its properties in detail.

    ↳ hep-phhep-lathep-thnucl-th+1PRD(2023)·20 citations
  6. 06

    Planar degeneracy of the three-gluon vertex

    A. C. Aguilar🇧🇷 · M. N. Ferreira🇪🇸 · J. Papavassiliou🇪🇸 · L. R. Santos🇧🇷

    We present a detailed exploration of certain outstanding features of the transversely-projected three-gluon vertex, using the corresponding Schwinger-Dyson equation in conjunction with key results obtained from quenched lattice simulations. The main goal of this study is the scrutiny of the approximate property denominated ``planar degeneracy'', unveiled when the Bose symmetry of the vertex is properly exploited. The planar degeneracy leads to a particularly simple parametrization of the vertex, reducing its kinematic dependence to essentially a single variable. Our analysis, carried out in the absence of dynamical quarks, reveals that the planar degeneracy is particularly accurate for the description of the form factor associated with the classical tensor, for a wide array of arbitrary kinematic configurations. Instead, the remaining three form factors display considerable violations of this property. In addition, and in close connection with the previous point, we demonstrate the numerical dominance of the classical form factor over all others, except in the vicinity of the soft-gluon kinematics. The final upshot of these considerations is the emergence of a very compact description for the three-gluon vertex in general kinematics, which may simplify significantly nonperturbative applications involving this vertex.

    ↳ hep-phhep-latnucl-thEPJC(2023)·21 citations
  7. 07

    Detectability of a phase transition in neutron star matter with third-generation gravitational wave interferometers

    C. Mondal🇫🇷 · M. Antonelli🇫🇷 · F. Gulminelli🇫🇷 · M. Mancini🇫🇷 · J. Novak🇫🇷 · M. Oertel🇫🇷

    Possible strong first-order hadron-quark phase transitions in neutron star interiors leave an imprint on gravitational waves, which could be detected with planned third-generation interferometers. Given a signal from the late inspiral of a binary neutron star (BNS) coalescence, %the possibility of assessing the presence of such a phase transition depends on the precision that can be attained in the determination of the tidal deformability parameter, as well as on the model used to describe the hybrid star equation of state. For the latter, we employ here a phenomenological meta-modelling of the equation of state that largely spans the parameter space associated with both the low density phase and the quark high density compatible with current constraints. We show that with a network of third-generation detectors, a single loud BNS event might be sufficient to infer the presence of a phase transition at low baryon densities with an average Bayes factor , up to a luminosity distance ( 300 Mpc).

    ↳ astro-ph.HEnucl-thMNRAS(2023)·20 citations

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first authorsco-authorsvia INSPIRE