Color-flavor dependence of the Nambu-Jona-Lasinio model and QCD phase diagram  

作　　者：Aftab Ahmad Ali Murad 

机构地区：[1]Institute of Physics,Gomal University,29220,D.I.Khan,Khyber Pakhtunkhaw,Pakistan

出　　处：《Chinese Physics C》2022年第8期128-140,共13页中国物理C（英文版）

摘　　要：We study the dynamical chiral symmetry breaking/restoration for various numbers of light quarks flavors N_(f) and colors N_(c) using the Nambu-Jona-Lasinio(NJL) model of quarks in the Schwinger-Dyson equation framework,dressed with a color-flavor dependence of effective coupling.For fixed N_(f)=2 and varying N_(c),we observe that the dynamical chiral symmetry is broken when N_(c) exceeds its critical value N_(c)^(c)≈2.2.For a fixed N_(c)=3 and varying N_(f),we observe that the dynamical chiral symmetry is restored when Nf reaches its critical value N_r^(c)≈8.Strong interplay is observed between N_(c) and N_(f),i.e.,larger values of N_(c) tend to strengthen the dynamical generated quark mass and quark-antiquark condensate,while higher values of N_(f) suppress both parameters.We further sketch the quantum chromodynamics(QCD) phase diagram at a finite temperature T and quark chemical potential μ for various N_(c) and N_(f).At finite T and μ,we observe that the critical number of colors N_(c)^(c) is enhanced,whereas the critical number of flavors N_(f)^(c) is suppressed as T and μ increase.Consequently,the critical temperature T_(c),μ_(c),and co-ordinates of the critical endpoint(T_(c)^(E),μ_(c)^(E)) in the QCD phase diagram are enhanced as N_(c) increases and suppressed when N_(f) increases.Our findings agree with the lattice QCD and Schwinger-Dyson equations predictions.

关 键 词：chiral symmetry breaking Schwinger-Dyson equation finite temperature and density QCD phase diagram 

分 类 号：O572.33[理学—粒子物理与原子核物理]