Vector meson form factors and their quark-mass dependence

Abstract

The electromagnetic form factors of vector mesons are calculated in an explicitly Poincaré covariant formulation, based on the Dyson--Schwinger equations of QCD, that respects electromagnetic current conservation, and unambiguously incorporates effects from vector meson poles in the quark-photon vertex. This method incorporates a 2-parameter effective interaction, where the parameters are constrained by the experimental values of chiral condensate and $f_{\pi }$. This approach has successfully described a large amount of light-quark meson experimental data, e.g. ground state pseudoscalar masses and their electromagnetic form factors; ground state vector meson masses and strong and electroweak decays. Here we apply it to predict the electromagnetic properties of vector mesons. The results for the static properties of the $\rho$-meson are: charge radius $<r_{\rho }^2>=0.54{\mathrm{fm}}^2$, magnetic moment $\mu =2.01$, and quadrupole moment $\mathcal{Q}=-0.41$. We investigate the quark mass dependence of these static properties and find that our results at the charm quark mass are in agreement with recent lattice simulations. The charge radius decreases with increasing quark mass, but the magnetic moment is almost independent of the quark mass.

13 pages, 7 figures

References in corpus (2)

• Mind the gap
• Hadron Physics and the Dyson--Schwinger Equations of QCD

Cited by in corpus (5)

• Hadron Properties and Dyson-Schwinger Equations
• Gravitational Form Factors of Vector Mesons in an AdS/QCD Model
• Beyond the rainbow: effects from pion back-coupling
• Manifestation of three-body forces in three-body Bethe-Salpeter and light-front equations
• Current quark mass dependence of nucleon magnetic moments and radii