The electromagnetic Sigma-to-Lambda transition form factors with coupled-channel effects in the space-like region

Abstract

Using dispersion theory, the electromagnetic Sigma-to-Lambda transition form factors are expressed as the product of the pion electromagnetic form factor and the $\Sigma \bar{\Lambda }\to \pi \pi$ scattering amplitudes with the latter estimated from SU(3) chiral perturbation theory including the baryon decuplet as explicit degrees of freedom. The contribution of the $K\bar{K}$ channel is also taken into account and the $\pi \pi$-$K\bar{K}$ coupled-channel effect is included by means of a two-channel Muskhelishvili-Omnès representation. It is found that the electric transition form factor shows a significant shift after the inclusion of the $K\bar{K}$ channel, while the magnetic transition form factor is only weakly affected. However, the $K\bar{K}$ effect on the electric form factor is obscured by the undetermined coupling $h_A$ in the three-flavor chiral Lagrangian. The error bands of the Sigma-to-Lambda transition form factors from the uncertainties of the couplings and low-energy constant in three-flavor chiral perturbation theory are estimated by a bootstrap sampling method.

16 pages, 10 figures

References in corpus (24)

• The pion-pion scattering amplitude. IV: Improved analysis with once subtracted Roy-like equations up to 1100 MeV
• Electromagnetic excitation of the Delta(1232)-resonance
• Dispersion analysis of the nucleon form factors including meson continua
• The size of the proton - closing in on the radius puzzle
• The proton charge radius
• Theoretical Constraints and Systematic Effects in the Determination of the Proton Form Factors
• MO analysis of the high statistics Belle results on $\gamma \gamma \to {\pi }^{+}{\pi }^{-},{\pi }^0{\pi }^0$ with chiral constraints
• On the pi pi continuum in the nucleon form factors and the proton radius puzzle
• Roy-Steiner equations for pion-nucleon scattering
• New insights into the nucleon's electromagnetic structure
• Nucleon Electromagnetic Form Factors in the Timelike Region
• Dispersive analysis of the scalar form factor of the nucleon
• Octet-baryon axial-vector charges and SU(3)-breaking effects in the semileptonic hyperon decays
• Aspects of meson-baryon scattering in three- and two-flavor chiral perturbation theory
• The electromagnetic form factors of the $\Lambda$ in the timelike region
• On the chiral effective meson-baryon Lagrangian at third order
• High-precision determination of the electric and magnetic radius of the proton
• Dispersion-theoretical analysis of the electromagnetic form factors of the nucleon: Past, present and future
• Hyperon electromagnetic form factors in the timelike region
• The proton radius (puzzle?) and its relatives
• Dispersion representations and anomalous singularities of the triangle diagram
• Six-pion amplitude
• The electromagnetic form factors of the transition from the spin-3/2 Sigma to the Lambda hyperon
• Axial-vector form factors of the baryon octet and chiral symmetry

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• Novel method to extract the femtometer structure of strange baryons using the vacuum polarization effect
• Deciphering the mechanism of $J/\psi$-nucleon scattering
• Dispersive Analysis of $D$- and $B$-Meson Form Factors with Chiral and Heavy-Quark Constraints
• Baryon Form Factors