SU(2) x SU(2) nonlocal quark model with confinement

Abstract

The nonlocal version of the SU (2) × SU (2) symmetric four-quark interaction of the NJL type is considered. Each of the quark lines contains the form factors. These form factors remove the ultraviolet divergences in quark loops. The additional condition on quark mass function m(p) ensures the absence of the poles in the quark propagator(quark confinement). The constituent quark mass m(0) is expressed thought the cut-off parameter Λ, m(0) = Λ = 340 MeV in the chiral limit. These parameters are fixed by the experimental value of the weak pion decay and allow us to describe the mass of the light scalar meson, strong decay ρ → ππ and D/S ratio in the decay a1 → ρπ in satisfactory agreement with experimental data.

Mean-field expansion and meson effects in chiral condensate of analytically regularized Nambu-Jona-Lasinio model

“…In some sense this possible treatment has something in common with non-local variants of the NJL model (see [10], [12]). …”

Thermal nonlocal Nambu–Jona-Lasinio model in the real time formalism

“…Perturbative QCD cannot describe confinement and, although lattice QCD is able to reproduce successfully hadron properties, like masses and coupling constants [4], it has problems when dealing with finite baryon chemical potential (the sign problem). However, there are effective models which include explicitly confinement, as, for example, different versions of the bag model [5][6][7][8], Dyson-Schwinger models [9-13], or the Polyakov loop effective action coupled to DysonSchwinger or NJL models [14][15][16][17].The nonlocal NJL model (nNJL) is another attempt in this direction [18][19][20][21]. When the gluon degrees of freedom are integrated out in the QCD action, a nonlocal quark action emerges and confinement should be hidden there.…”

“…The nonlocal NJL model (nNJL) is another attempt in this direction [18][19][20][21]. When the gluon degrees of freedom are integrated out in the QCD action, a nonlocal quark action emerges and confinement should be hidden there.…”

Scalar σ meson at a finite temperature in a nonlocal quark model

“…We use the Euclidean metric 3. A similar confining propagator without poles is used in a nonlocal model of NJL type[10, 11].…”