Related papers: Pseudoscalar Transition Form Factors from Rational…
Given the unique role played by the gravitational form factors (GFFs) in unraveling the internal mechanics of hadrons, we examine the GFFs of ground state pseudoscalar mesons $\pi$, $\eta_c$, $\eta_b$ and the hypothetical {\em strangeonium}…
The applications of the consistently coupled Schwinger-Dyson and Bethe-Salpeter approach to the eta-eta' complex are extended to the two-photon transition form factors of eta and eta' for spacelike transferred momenta. We compare our…
Hadron electromagnetic form factors of hadrons in the time-like region at the boundary of the physical region is considered. The energy behaviour of the form factor is shown to be dominantely determined by the strong hadron-antihadron…
We analyze the pion transition form factor using dispersion theory. We calculate the singly-virtual form factor in the time-like region based on data for the $e^+e^-\to 3\pi$ cross section, generalizing previous studies on…
The behavior of neutral pseudoscalar mesons $\pi^0, \eta$ and $\eta'$ in hot and dense matter is investigated, in the framework of the three flavor Nambu-Jona-Lasinio model. Three different scenarios are considered: zero density and finite…
An approach for calculation of transition form factors of hydrogen-like elementary atoms (EA) is proposed. A general formula for bound-continuous transition form factors of EA is derived. It is shown that these form factors can be…
In semi-leptonic and other weak decays of mesons, the hadronic matrix elements of the operators in the weak Hamiltonian are parametrized by standard sets of independent, Lorentz invariant, form factors. For the case of pseudoscalar to…
This paper reports on Monte Carlo simulation results for future measurements of time-like proton electromagnetic form factors, $|G_{E}|$ and $|G_{M}|$, using the $\bar{p} p \rightarrow \mu^{+} \mu^{-}$ reaction at…
Eta-eta' mixing is discussed in the quark-flavor basis with the hypothesis that the decay constants follow the pattern of particle state mixing. On exploiting the divergences of the axial vector currents - which embody the axial vector…
We study the $P\to\gamma\,\gamma^*$ ($P=\pi^0,\eta,\eta'$) transition form factors by means of the local-duality (LD) version of QCD sum rules. For the case of $\eta$ and $\eta'$, the conventional LD model provides a good description of the…
We present an improved calculation of $B\to$ light pseudoscalar formfactors from light-cone sum rules, including one-loop radiative corrections to twist-2 and twist-3 contributions, and leading order twist-4 corrections. The total…
The evaluation of the numerically dominant pseudoscalar-pole contribution to hadronic light-by-light scattering in the muon g-2 involves the pseudoscalar-photon transition form factor F_{P gamma^* gamma^*}(-Q_1^2, -Q_2^2) with P = pi^0,…
In the covariant light-front quark model, we investigate the form factors of $B_c$ decays into $D, D^*, D_s, D_s^*, \eta_c, J/\psi, B, B^*, B_s, B_s^*$ mesons. The form factors in the spacelike region $q^2<0$ are directly evaluated. To…
Within the Dyson-Schwinger equation approach to modeling QCD for meson physics, we present new results for $g_{\rho\pi\pi}$ and the coupling constants and form factors for the transitions $\gamma^\ast \pi \rho$ and $\gamma^\ast \pi^0…
The elastic and $\gamma \to \pi$ transition form factors of the pion along with its usual static observables are calculated within a light-front field approach to the constituent quark model. The focus of this exercise in a simple model is…
A method to determine masses, widths and coupling constants of vector mesons, like phi(1020), omega(782) and rho0(770) recurrences is defined. Starting from data on decay rates and cross sections for the processes: phi -> M_I gamma, phi ->…
The composition of the eta and eta' mesons has long been a source of discussion and is of current interest with new experimental results appearing. We investigate what can be learnt from a number of different processes: V to P gamma and P…
The exact form of the form-factor associated with a meson-photon-photon vertex is not known. Different suggestions exist, based on constraints from QCD and on recent experiments. Four different form-factors are studied in this article. We…
An important goal of ongoing and future experiments is to explore spectra and transition form factors of baryons with non-zero strangeness. Of particular interest is the transition form factor$\gamma^{(*)} \Sigma^0 \rightarrow \Lambda$ in…
Light front formalism for composite systems is presented. Derivation of equations for bound state and scattering problems are given. Methods of constructing of elastic form factors and scattering amplitudes of composite particles are…