Nuclear Theory·nucl-th

Monday·May 1, 2023

8 papers—2 primary·6 cross-listed

03
[Submitted on 27 Apr 2023] (cross-list from hep-ph)
Superfast Quarks in Deuterium
Dmitriy N. Kim🇺🇸 · Gerald A. Miller🇺🇸
An extension to our previous study on Nuclear Parton Distribution Functions (nPDFs) using Light-Front Holographic Quantum Chromodynamics (LFHQCD) is presented. We focus on applying the effects of nucleon motion inside the nucleus (Fermi motion/smearing) to deuterium, extending our nPDFs (and hence the DIS $F_{2}$ structure function for deuterium, $F_{2}^{D}$ ) to the superfast, $x > 1$ , region. We utilize four different deuteron wavefunctions (AV18, NijmI, NijmII, Nijm93) in this study. We find that our model, with no additional new parameters, is in excellent agreement with deuterium EMC ratio data obtained from the BONuS experiment. Looking beyond conventional nuclear physics, and in anticipation of ongoing 12 GeV experiments at Jefferson Lab, we use a LFHQCD ansatz to predict the contributions of an exotic six-quark state to $F_{2}^{D}$ in the superfast region. Our results are that the effects of using other potentials are about the same magnitude as six-quark effects - both have small effects in $x < 1$ , but have significant contributions at $x > 1$ .
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2304.14552 [pdf]
PRC(2024)·0 citations
04
[Submitted on 27 Apr 2023] (cross-list from hep-th)
Causality and stability in first-order conformal anisotropic hydrodynamics
Fabio S. Bemfica🇧🇷 · Mauricio Martinez🇺🇸 · Masoud Shokri🇩🇪
We formulate the first-order dissipative anisotropic hydrodynamical theory for a relativistic conformal uncharged fluid, which generalizes the Bemfica-Disconzi-Noronha-Kovtun first-order viscous fluid framework. Our approach maintains causal behavior in the nonlinear regime with or without general relativity coupling, and we derive and analyze the constraints on transport coefficients imposed by causality. We demonstrate the causal and stable behavior of our theory in specific cases, including the discussion of nonlinear causality as well as stability for linearized perturbations. We apply our newly developed first-order anisotropic theory to the Bjorken flow and show how causality and stability impose constraints on the behavior of the early-time attractor.
Comments:
Matches the published version
Subjects:
High Energy Physics — Theory (hep-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th); Fluid Dynamics (physics.flu-dyn)
arXiv:
2304.14563 [pdf]
PRD(2023)·6 citations
05
[Submitted on 28 Apr 2023] (cross-list from hep-ph)
Conserved number fluctuations under global rotation in a hadron resonance gas model
Gaurav Mukherjee🇮🇳 · Dipanwita Dutta🇮🇳 · Dipak Kumar Mishra🇮🇳
Net-baryon number, net-charge and net-strangeness fluctuations measured in ultra-relativistic heavy-ion collisions may reveal details and insights into the quark-hadron transition, hadrochemical freeze-out and possibly aid in the search of the QCD critical point. By scanning in collision energy, current and upcoming heavy-ion facilities aim to explore the finite density regime where the critical point may lie. Effects due to rotation are also expected in case of peripheral collisions and we report on conserved number susceptibilities as calculated in the hadron resonance gas model augmented by a global angular velocity. Since these quantities are directly related to the experimentally measurable moments of the corresponding distributions our results show the possible impact of vorticity on the theoretical baseline and should be useful for referencing with experimental data and QCD-based calculations.
Comments:
9 pages, 6 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2304.14658 [pdf]
EPJC(2024)·13 citations
06
[Submitted on 28 Apr 2023] (cross-list from hep-ph)
Building models of quarks and gluons with an arbitrary number of colors using Cartan-Polyakov loops
Renan Câmara Pereira🇵🇹 · Pedro Costa🇵🇹
In this work we introduce the concept of Cartan-Polyakov loops, a special subset of Polyakov loops in the fundamental representation of the $SU (N_{c})$ group, with charges $k = 1, \dots, (N_{c} - 1) /2$ . It constitutes a sufficient set of independent degrees of freedom and it is used to parametrize the thermal Wilson line. Polyakov loops not contained in this set are classified as non-Cartan-Polyakov loops. Using properties of the characteristic polynomial of the thermal Wilson line, we write a non-Cartan-Polyakov loop charge decomposition formula. This formalism allows one to readily build effective models of quarks and gluons with an arbitrary number of colors. We apply it to the Polyakov $-$ Nambu $-$ Jona-Lasinio model and to an effective glue model, in the mean field approximation, showing how to directly extend these models to higher values of $N_{c}$ .
Comments:
28 pages
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2304.14751 [pdf]
NPB(2024)·2 citations
07
[Submitted on 28 Apr 2023] (cross-list from hep-ph)
Molecular charmed baryons and pentaquarks from light-meson exchange saturation
Mao-Jun Yan🇨🇳 · Fang-Zheng Peng🇨🇳 · Manuel Pavon Valderrama🇨🇳
The spectrum of the $c q q$ baryons contains a few states whose nature is not clearly a three-quark composite and which might have a sizable baryon-meson component. Examples include the $Σ_{c} (2800)$ or the $Λ_{c} (2940)$ . Here we explore the spectrum of two-body systems composed of a light, octet baryon and a charmed meson (or antimeson) within a simple contact-range theory in which the couplings are saturated by light-meson exchanges. This results in the prediction of a series of composite anticharmed pentaquarks ( $c ˉ q q q q$ ) and singly-charmed baryons ( $c q ˉ q q q$ ). Among the later we find $J = \frac{1}{2}$ $Ξ D$ and $J = \frac{3}{2}$ $Ξ D^{*}$ bound states with masses matching those of the recently observed $Ω_{c} (3185)$ and $Ω_{c} (3327)$ baryons.
Comments:
14 pages, 6 tables, corresponds to published version
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2304.14855 [pdf]
PRD(2024)·29 citations
08
[Submitted on 28 Apr 2023] (cross-list from hep-ph)
A contact interaction model for the $η$ and $η^{'}$ mesons in a SDE-BSE approach to QCD: masses, decay widths and transition form factors
Bilgai Almeida Zamora🇲🇽 · Enrique Carreon Martínez🇲🇽 · Jorge Segovia🇪🇸 · J.J. Cobos-Martínez🇲🇽
We construct a contact interaction model for the $η$ and $η^{'}$ mesons in the SDE-BSE approach to QCD and compute several static properties of these mesons and their transition form factors. We find that this model gives an excellent description of the $η$ and $η^{'}$ static properties, namely their masses, decay width and decay constants. However, a contact interaction disagrees with experimental data for $Q^{2}$ greater than 2 GeV $^{2}$ , and produces transition form factors in conflict with perturbative QCD prediction. This is not surpring and the reasons for this are explained
Comments:
10 pages, 4 figures, submitted to PRD
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2304.14887 [pdf]
PRD(2023)·10 citations

Affiliations

first authorsco-authorsvia INSPIRE

Superfast Quarks in Deuterium

Causality and stability in first-order conformal anisotropic hydrodynamics

Conserved number fluctuations under global rotation in a hadron resonance gas model

Building models of quarks and gluons with an arbitrary number of colors using Cartan-Polyakov loops

Molecular charmed baryons and pentaquarks from light-meson exchange saturation

A contact interaction model for the η and η′ mesons in a SDE-BSE approach to QCD: masses, decay widths and transition form factors

Affiliations

A contact interaction model for the $η$ and $η^{'}$ mesons in a SDE-BSE approach to QCD: masses, decay widths and transition form factors