Quark-antiquark states of the lightest scalar mesons within the Nambu-Jona-Lasinio model with flavor-dependent coupling constants

Abstract The quark-antiquark components of the U(3) lightest scalar meson nonet are investigated by considering Nambu-Jona-Lasinio model with flavor-dependent coupling constants that were derived (non-perturbative) gluon exchange. strange quark effective mass ($M_s^*$) is varied such strangeness content these mesons can be analyzed further. neutral states $S_0$, $S_8$ and $S_3$, adopted as most relevant respectively $\sigma(500)$, $f_0(980)$ $A_0^0(980)$ mesons. As a result, hierarchy between $S_0$ $S_8$, $K^*_0(700) - A_0(980)$ mesons, inverted corrected for quite low values constituent mass. Besides that, some particular $M_s^*$, masses $\sigma(500)$ also obtained mixing constant $G_{08}$. However, all nine not described simultaneously in self-consistent procedure, this goes along need non-quark-antiquark to completely describe their masses. A neutral-meson matrix defined leading angle found fitting correct value $\sigma (500) -f_0 (980)$ difference. Two different estimates strengths mixings $A_0^0 \to f_0$ $f_0 A_0^0$ proposed, somewhat behaviors. Firstly, assuming transitions intermediary flavor eigenstates secondly dynamical evolution. Results may good agreement experimental from BESS-III depending on