Light Meson Form Factors at near Physical Masses

Abstract

The ability for most hadrons to decay via strong interactions prevents the direct measurement of their electromagnetic properties. However, a detailed understanding of how these resonant states feature in scattering processes can allow one to disentangle such information from photo production processes. In particular, there has been increasing interest in the determination of magnetic dipole moments using such methods. In a recent study, Gudino et al. provide the first experimental determination of the magnetic dipole moment of the rho meson. To facilitate a comparison with this experimental determination, we present a calculation of the rho meson and pion electromagnetic form factors calculated in the framework of Lattice QCD. Using the PACS-CS 2+1 flavour full QCD gauge field configurations, we are able to access low $Q^2$ values at near-physical quark masses. Through the use of variational techniques, we control excited state systematics in the matrix elements of the lowest-lying states and gain access to the matrix elements of the first excited state. Our determination of the rho meson $g$-factor $g_{\rho }=2.21(8)$ is in excellent agreement with this experimental determination, but with a significantly smaller uncertainty.

arXiv comment16 pages, 13 figures

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Cited by in corpus (29)

• The resonant ${\pi }^{+}\gamma \to {\pi }^{+}{\pi }^0$ amplitude from Quantum Chromodynamics
• Elastic electromagnetic form factors of vector mesons
• Light mesons within the basis light-front quantization framework
• TMDs of Spin-one Targets: Formalism and Covariant Calculations
• Magnetic properties of ground-state mesons
• The radius of the rho meson determined from its decay constant
• The size of the pion from full lattice QCD with physical $u$, $d$, $s$ and $c$ quarks
• $\rho$ meson unpolarized generalized parton distributions with a light-front constituent quark model
• Nucleon matrix elements using the variational method in lattice QCD
• Rho meson form factors in a confining Nambu--Jona-Lasinio model
• Determination of the properties of vector mesons in external magnetic field by Quenched $SU(3)$ Lattice QCD
• Electroweak properties of pions in a nuclear medium
• The Mellin moments $⟨x⟩$ and $⟨x^2⟩$ for the pion and kaon from lattice QCD
• Magnetic moment of the rho meson in instant-form relativistic quantum mechanics
• Transition of $\rho \to \pi \gamma$ in Lattice QCD
• Valence-quark distributions of pions and kaons in a nuclear medium
• Quark anomalous magnetic moment and its effects on the $\rho$ meson properties
• Hadronic structure on the light-front VIII. Light scalar and vector mesons
• Constraining beyond the Standard Model nucleon isovector charges
• Off-forward gluonic structure of vector mesons
• Unpolarized generalized parton distributions of light and heavy vector mesons
• Unambiguous Extraction of the Electromagnetic Form Factors for Spin-1 Particles on the Light-Front
• Tensor polarizability of the vector mesons from $SU(3)$ lattice gauge theory
• Rho-pion transition form factors in the $k_T$ factorization formulism revisited
• $\Delta I=3/2$ and $\Delta I=1/2$ channels of $K\to \pi \pi$ decay at the physical point with periodic boundary conditions
• Valence quark distribution of light $\rho$ and heavy $J/\psi$ vector mesons in light-cone quark model
• Medium effects on the electromagnetic form factors of the $\rho$ meson
• Quadrupole moments of spin-1 systems: the rho meson, the S-wave deuteron and some general constraints
• Radiative Decays of Vector Mesons with Light-Cone Sum Rules