Compositeness is an important concept to promote a quantitative understanding of the inner structure for a molecular state. We introduce the compositeness formalism for the case of the resonance, as a generalization of bound-state case. We have also proposed a more general form of two-body scattering amplitude with explicit inclusion of CDD pole, which is more widely applicable than the...
We study the $\Lambda \overline{\Lambda}$ and $\Lambda_c \overline{\Lambda}_c$ systems in a constituent quark model with color–color, color–spin, and three-quark interactions. The effective baryon–antibaryon interaction is obtained using a variational approach in a constituent quark model. Our results indicate that compact bound states are possible in both strange and charmed sectors, although...
Effective field theories (EFTs) are a popular theoretical method in hadron physics and few-body physics. By employing dibaryon fields (or dimer fields) for a two-nucleon system, one can expand the terms around the unitarity limit; the expanded terms are naturally matched to effective range parameters, and the dibaryon (dimer) fields are useful tools to describe bound and resonant states for a...
We investigate the electromagnetic form factors of the nucleon using
an effective chiral theory based on the QCD instanton vacuum.
Here we take into account the momentum-dependent dynamical quark mass
originating from the instanton-induced 2$N_f$ quark interactions.
The momentum-dependent quark mass naturally plays the role of a regulator,
so that no additional regularization is needed....
