Nuclear Theory·nucl-th

Tuesday·September 19, 2023

21 papers—13 primary·8 cross-listed

14
[Submitted on 15 Sept 2023] (cross-list from hep-ph)
Constraining the low-energy S=-2 meson-baryon interaction with two-particle correlations
V. Mantovani Sarti🇩🇪 · A. Feijoo🇪🇸 · I. Vidaña🇮🇹 · A. Ramos🇪🇸 · F. Giacosa🇵🇱 · T. Hyodo🇯🇵 · Y. Kamiya🇯🇵
The two-particle correlation technique applied to $K^{-} Λ$ pairs in pp collisions at LHC recently provided the most precise data on the strangeness $S = - 2$ meson-baryon interaction. In this letter, we use for the first time femtoscopic data to constrain the parameters of a low-energy effective QCD Lagrangian. The tuned model delivers new insights on the molecular nature of the $Ξ (1620)$ and $Ξ (1690)$ states. This procedure opens the possibility to determine higher order corrections, directly constraining QCD effective models particularly in the multi-strange and charm sectors.
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2309.08756 [pdf]
PRD(2024)·41 citations
15
[Submitted on 17 Sept 2023] (cross-list from astro-ph.HE)
Effects of nuclear matter properties in neutron star mergers
Maximilian Jacobi🇩🇪 · Federico Maria Guercilena🇮🇹 · Sabrina Huth🇩🇪 · Giacomo Ricigliano🇩🇪 · Almudena Arcones🇩🇪 · Achim Schwenk🇩🇪
The dynamics in mergers of binary neutron star (BNS) systems depend sensitively on the equation of state (EOS) of dense matter. This has profound implications on the emission of gravitational waves (GWs) and the ejection of matter in the merger and post-merger phases and is thus of high interest for multi-messenger astronomy. Today, a variety of nuclear EOSs are available with various underlying microphysical models. This calls for a study to focus on EOS effects from different physical nuclear matter properties and their influence on BNS mergers. We perform simulations of equal-mass BNS mergers with a set of 9 different EOSs based on Skyrme density functionals. In the models, we systematically vary the effective nucleon mass, incompressibility, and symmetry energy at saturation density. This allows us to investigate the influence of specific nuclear matter properties on the dynamics of BNS mergers. We analyze the impact of these properties on the merger dynamics, the fate of the remnant, disk formation, ejection of matter, and gravitational wave emission. Our results indicate that some aspects of the merger are sensitive to the EOS around saturation density while others are sensitive to the behavior towards higher densities, e.g., characterized by the slope of the pressure as a function of density. The detailed density dependence of the EOS thus needs to be taken into account to describe its influence on BNS mergers.
Comments:
17 pages, 19 figures, published version
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2309.09233 [pdf]
MNRAS(2023)·22 citations
16
[Submitted on 17 Sept 2023] (cross-list from hep-lat)
Study of the effects of external imaginary electric field and chiral chemical potential on quark matter
Ji-Chong Yang🇨🇳 · Xin Zhang🇨🇳 · Jian-Xing Chen🇨🇳
The behavior of quark matter with both external electric field and chiral chemical potential is theoretically and experimentally interesting to consider. In this paper, the case of simultaneous presence of imaginary electric field and chiral chemical potential is investigated using the lattice QCD approach with $N_{f} = 1 + 1$ dynamical staggered fermions. We find that overall both the imaginary electric field and the chiral chemical potential can exacerbate chiral symmetry breaking, which is consistent with theoretical predictions. However we also find a non-monotonic behavior of chiral condensation at specific electric field strengths and chiral chemical potentials. In addition to this, we find that the behavior of Polyakov loop in the complex plane is not significantly affected by chiral chemical potential in the region of the parameters consider in this paper.
Comments:
21 pages, 20 figures
Subjects:
High Energy Physics — Lattice (hep-lat); cs.NA (cs.NA); High Energy Physics — Phenomenology (hep-ph); math.NA (math.NA); Nuclear Theory (nucl-th)
arXiv:
2309.09281 [pdf]
EPJC(2024)·6 citations
17
[Submitted on 17 Sept 2023] (cross-list from physics.flu-dyn)
Analytical structure of the binary collision integral and the ultrarelativistic limit of transport coefficients of an ideal gas
David Wagner · Victor E. Ambrus · Etele Molnar
In this paper we discuss the analytical properties of the binary collision integral for a gas of ultrarelativistic particles interacting via a constant cross-section. Starting from a near-equilibrium expansion over a complete basis of irreducible tensors in momentum space we compute the linearized collision matrices analytically. Using these results we then numerically compute all transport-coefficients of relativistic fluid dynamics with various power-counting schemes that are second-order in Knudsen and/or inverse Reynolds numbers. Furthermore, we also exactly compute the leading-order contribution with respect to the particle mass to the coefficient of bulk viscosity, the relaxation time, and other second-order transport coefficients of the bulk viscous pressure.
Comments:
Published version
Subjects:
Fluid Dynamics (physics.flu-dyn); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2309.09335 [pdf]
PRD(2024)·16 citations
18
[Submitted on 18 Sept 2023] (cross-list from hep-ph)
The LHC as a Neutrino-Ion Collider
Juan M. Cruz-Martinez🇨🇭 · Max Fieg🇺🇸 · Tommaso Giani🇳🇱 · Peter Krack🇳🇱 · Toni Mäkelä🇵🇱 · Tanjona Rabemananjara🇳🇱 · Juan Rojo🇳🇱
Proton-proton collisions at the LHC generate a high-intensity collimated beam of neutrinos in the forward (beam) direction, characterised by energies of up to several TeV. The recent observation of LHC neutrinos by FASER $ν$ and SND@LHC signals that this hitherto ignored particle beam is now available for scientific inquiry. Here we quantify the impact that neutrino deep-inelastic scattering (DIS) measurements at the LHC would have on the parton distributions (PDFs) of protons and heavy nuclei. We generate projections for DIS structure functions for FASER $ν$ and SND@LHC at Run III, as well as for the FASER $ν$ 2, AdvSND, and FLArE experiments to be hosted at the proposed Forward Physics Facility (FPF) operating concurrently with the High-Luminosity LHC (HL-LHC). We determine that up to one million electron- and muon-neutrino DIS interactions within detector acceptance can be expected by the end of the HL-LHC, covering a kinematic region in $x$ and $Q^{2}$ overlapping with that of the Electron-Ion Collider. Including these DIS projections into global (n)PDF analyses, specifically PDF4LHC21, NNPDF4.0, and EPPS21, reveals a significant reduction of PDF uncertainties, in particular for strangeness and the up and down valence PDFs. We show that LHC neutrino data enables improved theoretical predictions for core processes at the HL-LHC, such as Higgs and weak gauge boson production. Our analysis demonstrates that exploiting the LHC neutrino beam effectively provides CERN with a "Neutrino-Ion Collider" without requiring modifications in its accelerator infrastructure.
Comments:
42 pages, 22 figures. Added detailed studies on fluxes uncertainties
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2309.09581 [pdf]
EPJC(2024)·71 citations
19
[Submitted on 18 Sept 2023] (cross-list from hep-ph)
Triangle and box diagrams in coupled-channel systems from the chiral Lagrangian
Tobias Isken🇩🇪 · Xiao-Yu Guo🇨🇳 · Yonggoo Heo🇩🇪 · Csaba L. Korpa🇭🇺 · Matthias F.M. Lutz🇩🇪
We perform an analysis of triangle- and box-loop contributions to the generalized potential in the scattering of Goldstone bosons off the J^P= 0^- and 1^- charmed mesons. Particular emphasis is put on the use of on-shell mass parameters in such contributions in terms of a renormalization scheme that ensures the absence of power-counting violating terms. This is achieved with a systematically extended set of Passarino--Veltman basis functions, that leads to manifest power-counting conserving one-loop expressions and avoids the occurrence of superficial kinematical singularities. Compact expressions to chiral order three and four are presented that are particularly useful in coding such coupled-channel systems. Our formal results are generic and prepare analogous computations for other systems, like meson-baryon scattering from the chiral Lagrangian.
Comments:
58 pages, 7 figures and 2 tables, minor corrections and extensions
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2309.09695 [pdf]
PRD(2024)·8 citations
20
[Submitted on 18 Sept 2023] (cross-list from astro-ph.HE)
Quasi-periodic oscillations during magnetar giant flares in the strangeon star model
Hong-Bo Li · Yacheng Kang · Zexin Hu · Lijing Shao · Cheng-Jun Xia · Ren-Xin Xu
Soft gamma-ray repeaters (SGRs) are widely understood as slowly rotating isolated neutron stars. Their generally large spin-down rates, high magnetic fields, and strong outburst energies render them different from ordinary pulsars. In a few giant flares (GFs) and short bursts of SGRs, high-confidence quasi-periodic oscillations (QPOs) were observed. Although remaining an open question, many theoretical studies suggest that the torsional oscillations caused by starquakes could explain QPOs. Motivated by this scenario, we systematically investigate torsional oscillation frequencies based on the strangeon-star (SS) model with various values of harmonic indices and overtones. To characterize the strong-repulsive interaction at short distances and the non-relativistic nature of strangeons, a phenomenological Lennard-Jones model is adopted. We show that, attributing to the large shear modulus of SSs, our results explain well the high-frequency QPOs ( $≳ 150 Hz$ ) during the GFs. The low-frequency QPOs ( $≲ 150 Hz$ ) can also be interpreted when the ocean-crust interface modes are included. We also discuss possible effects of the magnetic field on the torsional mode frequencies. Considering realistic models with general-relativistic corrections and magnetic fields, we further calculate torsional oscillation frequencies for quark stars. We show that it would be difficult for quark stars to explain all QPOs in GFs. Our work advances the understanding of the nature of QPOs and magnetar asteroseismology.
Comments:
9 pages, 7 figures; accepted by MNRAS
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); General Relativity and Quantum Cosmology (gr-qc); Nuclear Theory (nucl-th)
arXiv:
2309.09847 [pdf]
MNRAS(2024)·8 citations
21
[Submitted on 18 Sept 2023] (cross-list from hep-ph)
Cut structures and an observable singularity in the three-body threshold dynamics: the $T_{cc}^{+}$ case
Jun-Zhang Wang🇨🇳 · Zi-Yang Lin🇨🇳 · Shi-Lin Zhu🇨🇳
The three-body threshold effect, the distinctive and intriguing non-perturbative dynamics in the low-energy hadron-hadron scattering, has acquired compelling significance in the wake of the recent observation of the double-charm tetraquark $T_{cc}^{+}$ . This dynamics is characterized by the emergence of singular points and branch cuts within the interaction potential, occurring when the on-shell condition of the mediated particle is satisfied. The presence of these potential singularities indicates that the system is no longer Hermitian and also poses intractable challenges in obtaining exact solutions for dynamical scattering amplitudes. In this work, we develop a complex scaled Lippmann-Schwinger equation as an operation of analytical continuation of the $T$ matrix to resolve this problem. Through a practical application to the $D D^{*} \to D D^{*}$ process, we reveal complicated cut structures of the three-body threshold dynamics in the complex plane, primarily stemming from the one-pion exchange. Notably, our methodology succeeds in reproducing the $T_{cc}^{+}$ structure, in alignment with the quasi-bound pole derived from the complex scaling method within the Schrödinger equation framework. More remarkably, after solving the on-shell $T$ matrix on the positive real axis of momentum plane, we find an extra new structure in the $D D^{*}$ mass spectrum, which arises from a right-hand cut at a physical pion mass and should be observable in Lattice QCD simulations and future high-energy experiments.
Comments:
9 pages and 9 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2309.09861 [pdf]
PRD(2024)·15 citations

Affiliations

first authorsco-authorsvia INSPIRE