Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 0707.1269

Quarkonium Spectroscopy: Beyond One-Gluon Exchange

Johannes Eiglsperger
View original source ↗Read source document ↗Export metadata ↓

Abstract

In this work an improved potential model for quarkonium spectra (charmonium, bottomonium) is constructed. Beside the one-gluon exchange and a linear confinement potential, the model includes systematically effects from two-gluon exchange and the induced interaction (i.e. t-channel exchanges of quark-antiquark bound states). These turn out to be important in order to reproduce correctly the fine- and hyperfine structure of the charmonium and bottomonium states. It is demonstrated that such a satisfactory description of the quarkonium spectra can be obtained with parameters (quark masses, strong coupling constant and string tension) consistent with values of lattice simulations and QCD determinations.

Explore related subjects

hep-ph

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Johannes Eiglsperger. 2007-07-09. Quarkonium Spectroscopy: Beyond One-Gluon Exchange. https://arxiv.org/abs/0707.1269

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Quark and lepton mixing in the asymptotically safe Standard Model

The quark mixing (CKM) matrix is near-diagonal, whereas the lepton mixing (PMNS) matrix is not. We learn that both observations can generically be explained within an ultraviolet completion of the Standard Model with gravity. This ultraviolet completion results in approximate relations between CKM matrix elements. The accuracy with which these hold translates into the length of asymptotically safe scaling regimes. Experimental data are consistent with the theoretical expectations arising from a fixed-point cascade at transplanckian scales. Similar results would hold for the PMNS matrix if neutrino Yukawa couplings were large. The ultraviolet complete theory, therefore, must -- and in fact can -- avoid such an outcome. It achieves this through a dynamical mechanism that limits the size of neutrino Yukawa couplings. Thus, large neutrino mixing is intimately tied to small Dirac neutrino masses, $\sum m_ν \lesssim O(1)\, \rm eV$, and a mass gap in the Standard Model fermion masses.

hep-ph↗
arXiv2026

PINNs for Solving Two-Flavor Neutrino Oscillations in Vacuum and Matter Environments for Atmospheric and Reactor Neutrinos: A detailed analysis

Neutrino oscillations provide crucial insights into fundamental particle physics, with two-flavor approximations offering a robust framework for analyzing reactor and atmospheric phenomena. Currently, standard numerical integrators represent the gold standard for solving the associated evolution equations, achieving machine precision at negligible computational cost. However, Physics-Informed Neural Networks (PINNs) have recently emerged as a powerful surrogate model for handling high-dimensional systems, complex geometries, and inverse parameter estimation. In this paper, we establish a foundational proof-of-concept by applying PINNs to solve the coupled ordinary differential equations governing neutrino evolution in vacuum and constant-density matter profiles. We also discuss the theoretical framework encompassing vacuum mixing and the matter enhanced neutrino oscillations and rigorously benchmark the PINNs against standard NuFast and RK4 (Runge-Kutta 4) solutions. By carefully optimizing our network architecture, we demonstrate that PINNs can achieve high-precision agreement with experimental standards for reactor (low-energy) and atmospheric (high-energy) neutrinos, which we use as our case study. This paper evaluates the robustness of the PINNs approach through a comprehensive error analysis, establishing a baseline validation for its application to more challenging problems in neutrino physics, such as variable density profiles.

hep-ph↗
arXiv2026

On the magnetic counterpart of the Uehling correction

In this work, we investigate the magnetic properties of the quantum vacuum in the context of QED. We calculate the quantum relativistic correction of virtual particle-anti-particle pair creation to the field of a classical point-like idealized magnet. Using such correction, we find the induced currents stemming from the effect of the polarization of the vacuum, which behaves like a paramagnetic medium. We also calculate the correction to the electric dipole potential and show that the well-known symmetry between the classical fields of point electric and magnetic dipoles is broken at the quantum level. Lastly, to illustrate possible applications of our findings, we briefly discuss the effect of the corrections obtained here in the context of neutron-neutron scattering and the hyperfine splitting for hydrogen-like atoms.

hep-ph↗