Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · nucl-th/9403009

Nonperturbative aspects of the quark-photon vertex

Michael R. Frank
View original source ↗Read source document ↗Export metadata ↓

Abstract

The electromagnetic interaction with quarks is investigated through a relativistic, electromagnetic gauge-invariant treatment. Gluon dressing of the quark-photon vertex and the quark self-energy functions is described by the inhomogeneous Bethe-Salpeter equation in the ladder approximation and the Schwinger-Dyson equation in the rainbow approximation respectively. Results for the calculation of the quark-photon vertex are presented in both the time-like and space-like regions of photon momentum squared, however emphasis is placed on the space-like region relevant to electron scattering. The treatment presented here simultaneously addresses the role of dynamically generated $q\bar{q}$ vector bound states and the approach to asymptotic behavior. The resulting description is therefore applicable over the entire range of momentum transfers available in electron scattering experiments. Input parameters are limited to the model gluon two-point function, which is chosen to reflect confinement and asymptotic freedom, and are largely constrained by the obtained bound-state spectrum.

Explore related subjects

nucl-th

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Michael R. Frank. 1994-03-08. Nonperturbative aspects of the quark-photon vertex. https://doi.org/10.1103/physrevc.51.987

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

KEEP EXPLORING

Related papers

arXiv2026

Bayesian Inference of the Landau Parameter $G'_0$ from Joint Gamow-Teller Measurements

$G'_0$ is the leading-order Landau-Migdal parameter that characterizes the spin-isospin dependent nucleon-nucleon interaction. Consequently, the $G'_0$ is closely related to the Gamow-Teller resonance (GTR), the beta and double-beta decay rates of finite nuclei, the response of hot and dense nucleonic matter that modifies the neutrino-nucleon absorption rates in core-collapse supernovae (CCSNe) and binary neutron star (BNS) mergers, and finally the critical density for pion condensation in neutron stars. In this letter, for the first time, we report the $G'_0$ with quantified uncertainty in the framework of Bayesian inference, using a self-consistent standard Skyrme Random Phase Approximation (RPA) model and joint constraints from experimental GTR measurements on $^{208}\mathrm{Pb}$, $^{132}\mathrm{Sn}$, $^{90}\mathrm{Zr}$. Our extracted $G_0'$ at saturation density is $0.48\pm0.034$, which is close to the prediction of a few existing Skyrme models that consider spin-isospin observables but smaller than the traditional ones extracted from pion-exchange models. The reasons for this deviation, like the value of the nucleon effective mass $\frac{m^*}{m}$ and the density dependence of $G'_0$, are investigated. The density-dependent $G_0'$ values extracted in this work may guide the construction of new energy density functionals that aims to self-consistently describe the dense matter properties in the spin-isospin channel.

nucl-th↗
arXiv2026

QCD phase structure at high baryon density

Heavy-ion collisions provide unique access to the properties of QCD matter over a broad range of temperatures and baryon densities. We review recent progress in constraining the high-density phase structure of QCD, with particular emphasis on the microscopic inputs required for reliable transport modeling. We discuss cluster production, strange-particle interactions, collision dynamics at few-GeV energies, and the isospin dependence of the nuclear interaction, together with their impact on the interpretation of flow, yields, fluctuations, and possible critical signatures.

nucl-th↗
arXiv2026

Accessing zero-point fluctuations in high-energy nuclear collisions

Ultracentral high-energy collisions between identical nuclei are very sensitive to the size and shape of the frozen configuration of nucleons at the instant of the collision, an information that is encoded in the ground state wave functions of the colliding nuclei. The relative standard deviation of the size of the colliding system soon after the collision has recently been inferred from event-by-event fluctuations of the momentum per particle in collisions of $^{208}$Pb nuclei at the LHC, and since a single collision event produces thousands of particles, this information is very precise. We connect this extracted value to the magnitude of the zero-point fluctuations of the radius of the lead nucleus. The value that is extracted from the data is compatible with estimates based on nuclear sum rules, but is overestimated by classical Glauber-type modeling of high-energy collisions. The role of the Pauli principle in suppressing the fluctuations in closed-shell nuclei is underlined. It leads to a distinctive $A$ dependence that could be checked in collisions of smaller systems.

nucl-th↗