Strong Effective Coupling, Meson Ground States, and Glueball within Analytic Confinement

The phenomena of strong running coupling and hadron mass generating have been studied in the framework of a QCD-inspired relativistic model of quark-gluon interaction with infrared-confined propagators. We derived a meson mass equation and revealed a specific new behavior of the mass-dependent strong coupling α ^ s ( M ) defined in the time-like region. A new infrared freezing point α ^ s ( 0 ) = 1.03198 at origin has been found and it did not depend on the confinement scale Λ > 0 . Independent and new estimates on the scalar glueball mass, ‘radius’ and gluon condensate value have been performed. The spectrum of conventional mesons have been calculated by introducing a minimal set of parameters: the masses of constituent quarks and Λ . The obtained values are in good agreement with the latest experimental data with relative errors less than 1.8 percent. Accurate estimates of the leptonic decay constants of pseudoscalar and vector mesons have been performed

Charmonium radiative transitions, meson and glueball particle properties with the effective strong coupling

The particle properties of conventional mesons and scalar glueball, radiative transitions of charmonium excited states χcJ (J = 0, 1, 2) are studied in the framework of relativistic quark models with infrared confinement by taking into account the mass dependence of the effective strong coupling. A specific behaviour of the mass-dependent strong coupling with a freezing point αs (0) = 1.032 has been revealed. The spectrum and leptonic (weak) decay constants of conventional mesons have been calculated in good agreement with the latest experimental data. New estimates on the scalar glueball mass, ’radius’ and gluon condensate value have been obtained. Dominant radiative transitions of the charmonium orbital excitations χcJ → J/ψ + γ have been studied and the partial decay widths have been estimated with reasonable accuracy

The fermi coupling, mass spectrum and decay properties of mesons within the covariant confined quark model

Main properties of stable quark-antiquark bound states have been investigated by using a relativistic quark model with analytic confinement. A new insight into the problem of hadron mass generation is provided. It has been shown that the compositeness condition expressing the Yukawa coupling of the meson-quark interaction and the master equation relating the meson mass function to the Fermi coupling can together guarantee the equivalency of the both theories, thereby providing an interpretation of the meson field as a bound state of constituent quarks. A smooth behavior for the Fermi coupling G(M) obeying reasonable accuracy for the meson estimated masses M has been obtained. We have also updated our previous numerical results for the weak-decay constants as well as the electromagnetic decay widths of mesons. The obtained estimates are found in reasonable agreement with the recent experimental data

On the meson mass spectrum in the covariant confined quark model

We provide a new insight into the problem of generating the hadron mass spectrum in the framework of the covariant confined quark model. One of the underlying principles of this model is the compositeness condition which means that the wave function renormalization constant of the elementary hadron is equal to zero. In particular, this equation allows to express the Yukawa coupling of the meson fields to the constituent quarks as a function of other model parameters. In addition to the compositeness condition we also employ a further equation which relates the meson mass function to the Fermi coupling. Both equations guarantee that the Yukawa-type theory is equivalent to the Fermi-type theory thereby providing an interpretation of the meson field as the bound state of its constituent fermions (quarks). We evaluate the Fermi-coupling as a function of meson (pseudoscalar and vector) masses and vary the values of the masses in such a way to obtain a smooth behavior for the resulting curve. The mass spectrum obtained in this manner is found to be in good agreement with the experimental data. We also compare the behavior of our Fermi-coupling with the strong QCD coupling alpha_s calculated in an QCD-inspired approach