PaperPanorama
FAQ

Nuclear Theory·nucl-th

Wednesday·February 24, 2021

15 papers—8 primary·7 cross-listed

All15Primary8Cross-lists7
  1. 09

    [Submitted on 22 Feb 2021] (cross-list from astro-ph.HE)

    Supernova neutrino signals based on long-term axisymmetric simulations

    Hiroki Nagakura🇺🇸 · Adam Burrows🇺🇸 · David Vartanyan🇺🇸

    We study theoretical neutrino signals from core-collapse supernova (CCSN) computed using axisymmetric CCSN simulations that cover the post-bounce phase up to ~s. We provide basic quantities of the neutrino signals such as event rates, energy spectra, and cumulative number of events at some terrestrial neutrino detectors, and then discuss some new features in the late phase that emerge in our models. Contrary to popular belief, neutrino emissions in the late phase are not always steady, but rather have temporal fluctuations, the vigor of which hinges on the CCSN model and neutrino flavor. We find that such temporal variations are not primarily driven by proto-neutron star (PNS) convection, but by fallback accretion in exploding models. We assess the detectability of these temporal variations, and find that IceCube is the most promising detector with which to resolve them. We also update fitting formulae first proposed in our previous paper for which the total neutrino energy (TONE) emitted at the CCSN source is estimated from the cumulative number of events in each detector. This will be a powerful technique with which to analyze real observations, particularly for low-statistics data.

    Comments:
    Matching the publish version
    Subjects:
    High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics — Experiment (hep-ex); High Energy Physics — Theory (hep-th); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
    arXiv:
    2102.11283 [pdf]
    MNRAS(2021)·53 citations
  2. 10

    [Submitted on 22 Feb 2021] (cross-list from hep-th)

    On systems of maximal quantum chaos

    Mike Blake🇬🇧 · Hong Liu🇺🇸

    A remarkable feature of chaos in many-body quantum systems is the existence of a bound on the quantum Lyapunov exponent. An important question is to understand what is special about maximally chaotic systems which saturate this bound. Here we provide further evidence for the `hydrodynamic' origin of chaos in such systems, and discuss hallmarks of maximally chaotic systems. We first provide evidence that a hydrodynamic effective field theory of chaos we previously proposed should be understood as a theory of maximally chaotic systems. We then emphasize and make explicit a signature of maximal chaos which was only implicit in prior literature, namely the suppression of exponential growth in commutator squares of generic few-body operators. We provide a general argument for this suppression within our chaos effective field theory, and illustrate it using SYK models and holographic systems. We speculate that this suppression indicates that the nature of operator scrambling in maximally chaotic systems is fundamentally different to scrambling in non-maximally chaotic systems. We also discuss a simplest scenario for the existence of a maximally chaotic regime at sufficiently large distances even for non-maximally chaotic systems.

    Comments:
    28 pages, 3 figures, v2: minor clarification added, v3: typos corrected
    Subjects:
    High Energy Physics — Theory (hep-th); Strongly Correlated Electrons (cond-mat.str-el); nlin.CD (nlin.CD); Nuclear Theory (nucl-th); Quantum Physics (quant-ph)
    arXiv:
    2102.11294 [pdf]
    JHEP(2021)·51 citations
  3. 11

    [Submitted on 22 Feb 2021] (cross-list from hep-ph)

    Deconfinement Phase Transition in the Instanton-dyon Ensemble

    Dallas DeMartini🇺🇸 · Edward Shuryak🇺🇸

    Confinement remains one the most interesting and challenging nonperturbative phenomenon in non-Abelian gauge theories. Recent semiclassical (for SU(2)) and lattice (for QCD) studies have suggested that confinement arises from interactions of statistical ensembles of instanton-dyons with the Polyakov loop. In this work, we extend studies of semiclassical ensemble of dyons to the Yang-Mills theory. We find that such interactions do generate the expected first-order deconfinement phase transition. The properties of the ensemble, including correlations and topological susceptibility, are studied over a range of temperatures above and below . Additionally, the dyon ensemble is studied in the Yang-Mills theory containing an extra trace-deformation term. It is shown that such a term can cause the theory to remain confined and even retain the same topological observables at high temperatures.

    Comments:
    18 pages, 18 figures
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
    arXiv:
    2102.11321 [pdf]
    PRD(2021)·9 citations
  4. 12

    [Submitted on 23 Feb 2021] (cross-list from hep-ph)

    High-precision determination of the electric and magnetic radius of the proton

    Yong-Hui Lin🇩🇪 · Hans-Werner Hammer🇩🇪 · Ulf-G. Meißner🇩🇪

    Using dispersion theory with an improved description of the two-pion continuum based on the precise Roy-Steiner analysis of pion-nucleon scattering, we analyze recent data from electron-proton scattering. This allows for a high-precision determination of the electric and magnetic radius of the proton, fm and fm, where the first error refers to the fitting procedure using bootstrap and the data while the second one refers to the systematic uncertainty related to the underlying spectral functions.

    Comments:
    8 pages, 2 figures, more discussions and references added, version accepted for publication in Physics Letters B
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
    arXiv:
    2102.11642 [pdf]
    PLB(2021)·49 citations
  5. 13

    [Submitted on 23 Feb 2021] (cross-list from hep-th)

    Anomalous Hall instability in the Chern-Simons magnetohydrodynamics

    M. Kiamari🇮🇷 · M. Rahbardar🇮🇷 · M. Shokri🇮🇷 · N. Sadooghi🇮🇷

    The Chern-Simons magnetohydrodynamics (CSMHD) is introduced using a Maxwell-Chern-Simons (MCS) Lagrangian including an axion-like field . The MCS equation of motion derived from this Lagrangian consists of a modified current, including a chiral magnetic (CM) and an anomalous Hall (AH) current, in addition to the ordinary Ohm current of resistive magnetohydrodynamics (MHD). The former consists of an axial chemical potential, which is given in terms of the temporal comoving derivative of , and the latter arises from the spatial gradient of . As it turns out, the existence of the axial chemical potential is a nonequilibrium effect that plays no role in the linear stability analysis, whereas the AH current arises as in the first-order linear perturbation of the thermal equilibrium. We analyze the linear stability and causality of the CSMHD in a resistive and chiral medium. We show that the Alfven modes propagating sufficiently close to the direction of the magnetic field are unstable but causal. They are also accompanied by a genuine nonhydro mode. A stable mode in a particular direction can correspond to an unstable mode propagating in the exact opposite direction. The AH instability is a manifestation of a breakdown of the parity. A numerical analysis of the phase velocity confirms these results.

    Comments:
    31 pages, 10 figures
    Subjects:
    High Energy Physics — Theory (hep-th); Strongly Correlated Electrons (cond-mat.str-el); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
    arXiv:
    2102.11695 [pdf]
    PRD(2021)·6 citations
  6. 14

    [Submitted on 23 Feb 2021] (cross-list from nucl-ex)

    Revealing the structure of light pseudoscalar mesons at the Electron-Ion Collider

    John Arrington🇺🇸 · Carlos Ayerbe Gayoso🇺🇸 · Patrick C Barry🇺🇸 · Vladimir Berdnikov🇺🇸 · Daniele Binosi🇮🇹 · Lei Chang🇨🇳 · Markus Diefenthaler🇺🇸 · Minghui Ding🇮🇹 · Rolf Ent🇺🇸 · Tobias Frederico🇧🇷 · Yulia Furletova🇺🇸 · Tim J Hobbs🇺🇸 and 20 other authors

    How the bulk of the Universe's visible mass emerges and how it is manifest in the existence and properties of hadrons are profound questions that probe into the heart of strongly interacting matter. Paradoxically, the lightest pseudoscalar mesons appear to be the key to the further understanding of the emergent mass and structure mechanisms. These mesons, namely the pion and kaon, are the Nambu-Goldstone boson modes of QCD. Unravelling their partonic structure and the interplay between emergent and Higgs-boson mass mechanisms is a common goal of three interdependent approaches -- continuum QCD phenomenology, lattice-regularised QCD, and the global analysis of parton distributions -- linked to experimental measurements of hadron structure. Experimentally, the foreseen electron-ion collider will enable a revolution in our ability to study pion and kaon structure, accessed by scattering from the "meson cloud" of the proton through the Sullivan process. With the goal of enabling a suite of measurements that can address these questions, we examine key reactions to identify the critical detector system requirements needed to map tagged pion and kaon cross sections over a wide range of kinematics. The excellent prospects for extracting pion structure function and form factor data are shown, and similar prospects for kaon structure are discussed in the context of a worldwide programme. Successful completion of the programme outlined herein will deliver deep, far-reaching insights into the emergence of pions and kaons, their properties, and their role as QCD's Goldstone boson modes.

    Comments:
    73 pages, 27 figures
    Subjects:
    Nuclear Experiment (nucl-ex); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
    arXiv:
    2102.11788 [pdf]
    J.Phys.G(2021)·134 citations
  7. 15

    [Submitted on 23 Feb 2021] (cross-list from hep-ph)

    Phenomenological study of the anisotropic quark matter in the 2-flavor Nambu-Jona-Lasinio model

    He-Xia Zhang🇨🇳 · Yu-Xin Xiao🇨🇳 · Jin-Wen Kang🇨🇳 · Ben-Wei Zhang🇨🇳

    With the two flavor Nambu-Jona-Lasinio (NJL) model we carry out a phenomenological study on the chiral phase structure, mesonic properties and transport properties in a momentum-space anisotropic quark matter. To calculate transport coefficients we have utilized the kinetic theory in the relaxation time approximation, where the momentum anisotropy is embedded in the estimation of both distribution function and the relaxation time. It is shown that an increase of the anisotropy parameter may results in a catalysis of chiral symmetry breaking. The critical endpoint (CEP) is shifted to smaller temperatures and larger quark chemical potentials as increases, the impact of momentum anisotropy on temperature of CEP is almost the same as that on the quark chemical potential of CEP. The meson masses and the associated decay widths also exhibit a significant dependence. It is observed that the temperature behavior of scaled shear viscosity and scaled electrical conductivity exhibit a similar dip structure, with the minima of both and shifting toward higher temperatures with increasing . Furthermore, we demonstrate that the Seebeck coefficient decreases when temperature goes up and its sign is positive, indicating the dominant carriers for converting the temperature gradient to the electric field are up-quarks. The Seebeck coefficient is significantly enhanced with a large for the temperature below the critical temperature.

    Comments:
    20 pages, 10figures
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
    arXiv:
    2102.11792 [pdf]
    Nucl.Sci.Tech.(2022)·19 citations

Affiliations

first authorsco-authorsvia INSPIRE