The color number Nc-dependence of the interplay between quark-antiquark condensates (q^-q) and diquark condensates (qq) in vacuum in two-flavor four-fermion interaction models is researched. The results show that ...The color number Nc-dependence of the interplay between quark-antiquark condensates (q^-q) and diquark condensates (qq) in vacuum in two-flavor four-fermion interaction models is researched. The results show that the Gs-Hs (the coupling constant of scalar (q^-q)2-scalar (qq)2 channel) phase diagrams will be qualitatively consistent with the case of Nc = 3 as Nc varies in 4D Nambu-Jona-Lasinio model and 219 Gross Neveu (GN) model, However, in 3D GN model, the behavior of the Gs-Hp (the coupling constant of pseudoscalar (qq)^2 channel) phase diagram will obviously depend on No. The known characteristic that a 3D GN model does not have the coexistence phase of the condensates (q^-q) and (qq) is proven to appear only in the case of Nc ≤ 4. In all the models, the regions occupied by the phases containing the diquark condensates (qq) in corresponding phase diagrams will gradually decrease as Nc grows up and finally go to zero if Nc → ∞, i.e. in this limit only the pure (q^-q) phase could exist.展开更多
基金supported by the National Natural Science Foundation of China under Grant No. 10475113
文摘The color number Nc-dependence of the interplay between quark-antiquark condensates (q^-q) and diquark condensates (qq) in vacuum in two-flavor four-fermion interaction models is researched. The results show that the Gs-Hs (the coupling constant of scalar (q^-q)2-scalar (qq)2 channel) phase diagrams will be qualitatively consistent with the case of Nc = 3 as Nc varies in 4D Nambu-Jona-Lasinio model and 219 Gross Neveu (GN) model, However, in 3D GN model, the behavior of the Gs-Hp (the coupling constant of pseudoscalar (qq)^2 channel) phase diagram will obviously depend on No. The known characteristic that a 3D GN model does not have the coexistence phase of the condensates (q^-q) and (qq) is proven to appear only in the case of Nc ≤ 4. In all the models, the regions occupied by the phases containing the diquark condensates (qq) in corresponding phase diagrams will gradually decrease as Nc grows up and finally go to zero if Nc → ∞, i.e. in this limit only the pure (q^-q) phase could exist.