In this article, we study the structure of the ρ meson in the framework of the coupled rainbow Schwinger-Dyson equation and ladder Bethe-Salpeter equation with the confining effective potential. The renormalization of the u and d quarks is heavy, the mass poles in the time-like region are absent which implements confinement naturally. The Bethe-Salpeter amplitudes of the ρ meson have the same t...

In this article, we investigate the structures of the pseudoscalar charmonium and bottomonium in the framework of the coupled rainbow SchwingerDyson equation and ladder Bethe-Salpeter equation with the confining effective potential (infrared modified flat bottom potential). As the current masses are very large, the dressing or renormalization for the c and b quarks are tender, however, mass pol...

Heavy Baryon Chiral Perturbation Theory (HBChPT) to leading order provides a kernel to solve the Bethe-Salpeter equation for the P33 (∆(1232)-channel) π − N system, in the infinite nucleon mass limit. Crossed Born terms include, when iterated within the Bethe-Salpeter equation, both all oneand some two-pion intermediate states, hence preserving elastic unitarity below the two-pion production th...

In this article, we investigate the structures of the pseudoscalar charmonium and bottomonium in the framework of the coupled rainbow SchwingerDyson equation and ladder Bethe-Salpeter equation with the confining effective potential (infrared modified flat bottom potential). As the current masses are very large, the dressing or renormalization for the c and b quarks are tender, however, mass pol...

After a short survey of the Klein Paradox in 3-dimensional relativistic equations , there is a detailed consideration of Dirac modified equation, which follows by one particle overweight. It is shown, that the spin-orbital coupling is excluded in this equation as a result of pseudospin symmetry. That is why the separation of variables and reduction to radial equation is possible with standard m...