Related papers: Dispersion-theoretical analysis of the electromagn…
We review recent experimental and theoretical results for the electromagnetic form factors of hyperons (Y) in the timelike region, accessible in the reactions $e^+e^-\to \bar YY$. Specifically, we focus on the final states $\bar…
We use chiral perturbation theory to study the extrapolations necessary to make physical predictions from lattice QCD data for the electromagnetic form factors of pseudoscalar mesons. We focus on the quark mass, momentum, lattice spacing,…
We present a comprehensive analysis of form factors for two light pseudoscalar mesons induced by scalar, vector, and tensor quark operators. The theoretical framework is based on a combination of unitarized chiral perturbation theory and…
Some recent advances in the theoretical description of the Nucleon electromagnetic form factors, both in the space- and time-like regions, will be briefly illustrated. In particular, both the present stage of the lattice calculations and…
The electromagnetic form factors of light and heavy pseudoscalar mesons are calculated within two covariant constituent-quark models, a light-front and a dispersion relation approach. We investigate the details and physical origins of the…
We perform an analysis of $\Lambda_b\to\Lambda(1520)$ local form factors. We use dispersive techniques to provide a model-independent parametrisation of the form factors that can be used in the whole kinematic region. We use lattice QCD…
We derive a theoretically allowed domain for the charge radius $\rho$ and curvature $c$ of the Isgur-Wise function describing the decay $\Lambda_b \to \Lambda_c l {\bar \nu_l}$. Our method uses crossing symmetry, dispersion relations and…
In this study, we employ a modified soft-wall holographic model with four flavors to investigate the meson spectra, decay constants, electromagnetic form factors, and charge radius of various mesons. We obtain the spectra for vector, axial…
In the light of the new data on the various neutron and proton electromagnetic form factors taken in recent years, we update the dispersion-theoretical analysis of the nucleon electromagnetic form factors from the mid-nineties. The…
The experimental data on the electromagnetic form factor of charged pions available at spacelike momenta are analyzed using the Dispersive Matrix (DM) approach, which describes the momentum dependence of hadronic form factors without…
The form factors of the light pseudoscalar mesons are investigated in a dispersive formalism based on hadronic unitarity, analyticity and the OPE expansion of the QCD Green functions. We propose generalizations of the original mathematical…
The Taylor coefficients c and d of the Pion EM form factor are constrained using analyticity, knowledge of the phase of the form factor in the time-like region, 4 m_pi^2 \le t \le \tin and its value at one space-like point, using as input…
We extend a recent analysis of the pion electromagnetic form factor constrained by the conformal symmetry to explore the time-like region. We show explicitly that the time-like form factor obtained by the analytic continuation of the…
A practical strategy is presented and successfully implemented to determine form factors in the time-like but unphysical (below threshold) region using dispersion relations, in a model independent way without any bias towards expected…
New possibilities of high precision measurements of hadron form factors in annihilation and scattering reactions over an unexplored kinematical region suggest a compared analysis, in view of a global description of the nucleon structure.
Electromagnetic form factors serve to explore the intrinsic structure of nucleons and their strangeness partners. With electron scattering at low energies the electromagnetic moments and radii of nucleons can be deduced. The corresponding…
The electromagnetic form factors of charged and neutral kaons are strongly constrained by their low-energy singularities, in the isovector part from two-pion intermediate states and in the isoscalar contribution in terms of $\omega$ and…
An approach for describing the electromagnetic form factors of hadrons, in the space- and time-like regions, within a constituent quark model on the light front is shortly illustrated and calculations for the pion case are reported. Three…
We develop a methodology that enables us to extract accurately the electromagnetic Delta form factors and their momentum dependence. We test our approach in the quenched approximation as a preparation for a study using dynamical fermions.…
We present and demonstrate a version of Levinson's theorem especially dedicated to the asymptotic behavior of form factor phases. Indeed, as required by analyticity, form factors are multi-valued complex functions of a square four-momentum…