PaperPanorama

Nuclear Theory·nucl-th

Wednesday·May 4, 2022

6 papers3 primary·3 cross-listed

  1. 01

    [Submitted on 2 May 2022]

    Role of slow, out-of-equilibrium modes on the dynamic structure factor near the QCD critical point

    Golam Sarwar🇮🇳 · Md Hasanujjaman🇮🇳 · Jan-e Alam🇮🇳

    The role of slow out of equilibrium modes (OEM), introduced to extend the validity of hydrodynamics near the QCD critical point on the power spectrum of dynamical density fluctuations has been studied. We have used the equation of motion of slow modes for the situation when the extensive nature of thermodynamics is not altered due to the introduction of OEM. We find that the extensivity condition puts an extra constraint on the coupling of OEM with the four divergence of velocity. The dynamic structure factor (Snn) in presence of the OEM shows four Lorentzian peaks asymmetrically positioned about , whereas the dynamic structure factor without the presence of any OEM shows three well-known Lorentzian peaks. The width of the peaks are reduced in presence of OEM. We find that the asymmetric peaks originate due to the coupling of the out-of-equilibrium modes with the hydrodynamic modes. It is also shown that the OEM has negligible effects on Snn if first order hydrodynamics (relativistic Navier-Stokes) is used. The introduction of OEM reduces the width of the Rayleigh peak indicating the reduction in the decay rate of the fluctuation which leads to slowing down, a well-known characteristics of the critical end point (CEP).

    Comments:
    21 pages, 7 figures
    Subjects:
    Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
    arXiv:
    2205.01136 [pdf]
    PRD(2022)·3 citations
  2. 02

    [Submitted on 2 May 2022]

    Bayesian Inference of Phenomenological EoS of Neutron Stars with Recent Observations

    Emanuel V. Chimanski · Ronaldo V. Lobato · Andre R. Goncalves · Carlos A. Bertulani

    The description of stellar interior remains as a big challenge for the nuclear astrophysics community. The consolidated knowledge is restricted to density regions around the saturation of hadronic matter , regimes where our nuclear models are successfully applied. As one moves towards higher densities and extreme conditions up to five to twenty times , little can be said about the microphysics of such objects. Here, we employ a Markov Chain Monte Carlo (MCMC) strategy to access the variability of polytropic three-pircewised models for neutron star equation of state. With a fixed description of the hadronic matter, we explore a variety of models for the high density regimes leading to stellar masses up to . In addition, we also discuss the use of a Bayesian power regression model with heteroscedastic error. The set of EoS from the Laser Interferometer Gravitational-Wave Observatory (LIGO) was used as inputs and treated as data set for testing case.

    Comments:
    Minor typo fixes in the title and few typos corrected in the text. Added funding from Brookhaven
    Subjects:
    Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE)
    arXiv:
    2205.01174 [pdf]
    Particles(2023)·13 citations
  3. 03

    [Submitted on 3 May 2022]

    Deformed relativistic Hartree-Bogoliubov theory in continuum with a point-coupling functional. II. Examples of odd Nd isotopes

    DRHBc Mass Table Collaboration: Cong Pan · Myung-Ki Cheoun · Yong-Beom Choi · Jianmin Dong · Xiaokai Du · Xiao-Hua Fan · Wei Gao · Lisheng Geng · Eunja Ha · Xiao-Tao He · Jinke Huang · Kun Huang and 28 other authors

    The aim of this work is to extend the deformed relativistic Hartree-Bogoliubov theory in continuum (DRHBc) based on the point-coupling density functionals to odd- and odd-odd nuclei and examine its applicability by taking odd- Nd isotopes as examples. In the DRHBc theory, the densities and potentials with axial deformation are expanded in terms of Legendre polynomials, and the relativistic Hartree-Bogoliubov equations are solved in a Dirac Woods-Saxon basis to include the continuum effects. For an odd- or odd-odd nucleus, the blocking effect of unpaired nucleon(s) is taken into account with the equal filling approximation. To determine its ground state, an automatic blocking procedure is adopted, in which the orbital with the lowest quasiparticle energy is blocked during the iteration. This procedure is justified by comparing with the results from the orbital-fixed blocking calculations, in which the blocked orbital near the Fermi surface is fixed during the iteration. The ground states for both light and heavy nuclei can be provided by the automatic blocking procedure as the orbital-fixed blocking procedure, but with considerably reduced computational cost. The numerical details for even-even nuclei are found to be valid for odd- and odd-odd nuclei as well. Taking Nd isotopes including both even-even and odd- ones as examples, the calculated ground-state properties with PC-PK1 are in good agreement with the available experimental data. This work paves the way to construct the DRHBc mass table including all even-even, odd- and odd-odd nuclei in the nuclear chart.

    Comments:
    39 pages, 13 figures, and 1 table
    Subjects:
    Nuclear Theory (nucl-th)
    arXiv:
    2205.01329 [pdf]
    PRC(2022)·71 citations

Affiliations

first authorsco-authorsvia INSPIRE