Conserved charge fluctuations can be used to probe the phase structure of strongly interacting nuclear matter in relativistic heavy-ion collisions. To obtain the characteristic signatures of the conserved charge fluct...Conserved charge fluctuations can be used to probe the phase structure of strongly interacting nuclear matter in relativistic heavy-ion collisions. To obtain the characteristic signatures of the conserved charge fluctuations for the quantum chromodynamics(QCD) phase transition, we study the susceptibilities of dense quark matter up to eighth order in detail, using an effective QCD-based model. We studied two cases, one with the QCD critical end point(CEP) and one without owing to an additional vector interaction term. The higher order susceptibilities display rich structures near the CEP and show sign changes as well as large fluctuations. These can provide us information about the presence and location of the CEP. Furthermore, we find that the case without the CEP also shows a similar sign change pattern, but with a relatively smaller magnitude compared with the case with the CEP. Finally, we conclude that higher order susceptibilities of conserved charge can be used to probe the QCD phase structures in heavyion collisions.展开更多
We investigate nucleon mass splitting at finite isospin chemical potential in the frame of the two-flavour Nambu-Jona-Lasinio model. It is analytically proven that in the phase with explicit isospin symmetry breaking,...We investigate nucleon mass splitting at finite isospin chemical potential in the frame of the two-flavour Nambu-Jona-Lasinio model. It is analytically proven that in the phase with explicit isospin symmetry breaking, the proton mass decreases and the neutron mass increases linearly in the isospin chemical potential.展开更多
We discuss the sign and energy dependence of second to tenth order susceptibilities of the baryon number,charge number, and strangeness for the analysis of critical conditions in heavy ion collisions in the LHC and RH...We discuss the sign and energy dependence of second to tenth order susceptibilities of the baryon number,charge number, and strangeness for the analysis of critical conditions in heavy ion collisions in the LHC and RHIC by applying a modified Nambu-Jona-Lasinio model. This model is fitted to the quark condensate of the lattice QCD result at finite temperature and zero baryon chemical potential. The presence of a critical point made these susceptibilities deviate considerably from a Hadron-Resonance-Gas model that shows no criticality. The sign, magnitude, and energy dependence of these higher order fluctuations hint towards the existence and location of a critical point that could be discovered in future heavy ion collision experiments.展开更多
The effective Lagrangian of a finite volume system should, in principle, depend on the system size. In the framework of the Nambu-Jona-Lasinio(NJL) model, by considering the influence of quark feedback on the effectiv...The effective Lagrangian of a finite volume system should, in principle, depend on the system size. In the framework of the Nambu-Jona-Lasinio(NJL) model, by considering the influence of quark feedback on the effective coupling, we obtain a modified NJL model so that its Lagrangian depends on the volume. Based on the modified NJL model, we study the influence of finite volume on the chiral phase transition at finite temperature, and find that the pseudo-critical temperature of crossover is much lower than that obtained in the normal NJL model. This clearly shows that the volume dependent effective Lagrangian plays an important role in the chiral phase transitions at finite temperature.展开更多
In a previous work, we proposed an extended Nmnbu-Jona-Lasinio （NJL） model including heavy quark flavors. In this work, we will calculate strong and radiative decays of vector mesons in this extended NJL model, incl...In a previous work, we proposed an extended Nmnbu-Jona-Lasinio （NJL） model including heavy quark flavors. In this work, we will calculate strong and radiative decays of vector mesons in this extended NJL model, including light p, w, K＊, θ and heavy D＊, D＊s, B＊, Bs＊.展开更多
We study the two-color QCD matter with two fundamental quark flavors using the chiral perturbation theory and the Nambu-Jona-Lasinio(NJL)model.The effective Lagrangian is derived in terms of mesons and baryons,i.e.diq...We study the two-color QCD matter with two fundamental quark flavors using the chiral perturbation theory and the Nambu-Jona-Lasinio(NJL)model.The effective Lagrangian is derived in terms of mesons and baryons,i.e.diquarks.The low lying excitations lie in the extended SU(4)flavor symmetry space.We compute the leading order terms of the Lagrangian as a function of the baryon and axial isospin densities.After numerically solving the gap equations in the two-color NJL model,the phase diagram is obtained in the μ−ν5 plane.展开更多
The transport equation for the Nambu-Jona-Lasinio (NJL) model isderived phenomenologically. The finite-temperature effective mass for the quarkis analysed, By means of the Chapman-Enskog method and hydrodynamic ap-pro...The transport equation for the Nambu-Jona-Lasinio (NJL) model isderived phenomenologically. The finite-temperature effective mass for the quarkis analysed, By means of the Chapman-Enskog method and hydrodynamic ap-proach the different transport coefficients for the NJL plasma are calculated tothe first order in the relaxation time.展开更多
Based on an extended NJL model including heavy quark flavors, we calculate the form factors of pseudoscalar and vector mesons. After taking into account the vector-meson-dominance effect, which introduces a form facto...Based on an extended NJL model including heavy quark flavors, we calculate the form factors of pseudoscalar and vector mesons. After taking into account the vector-meson-dominance effect, which introduces a form factor correction to the quark vector coupling vertices, the form factors and electric radii of π^＋ and K^＋ pseudo-scalar mesons in the light flavor sector fit the experimental data well. The magnetic moments of the light vector mesons ρ^＋and K^＊＋are comparable with other theoretical calculations. The form factors in the light-heavy flavor sector are presented to compare with future experiments or other theoretical calculations.展开更多
We propose an extended Nambu-Jona-Lasinio model to include heavy mesons with heavy quark symmetry.The quark current-current interaction is generalized to include the heavy quark currents. In order to comply with the h...We propose an extended Nambu-Jona-Lasinio model to include heavy mesons with heavy quark symmetry.The quark current-current interaction is generalized to include the heavy quark currents. In order to comply with the heavy quark spin symmetry at the heavy quark limit,the dependence of the quark mass on the interaction strength is introduced. The light and heavy pseudo-scalar and vector mesons,their masses and the weak decay constants are calculated in the unified frame.展开更多
We explore the NJL model with Polyakov loops for a system of three colors and two flavors within the mean-field approximation,where both chiral symmetry and confinement are taken into account.We focus on the phase str...We explore the NJL model with Polyakov loops for a system of three colors and two flavors within the mean-field approximation,where both chiral symmetry and confinement are taken into account.We focus on the phase structure of the model and study the chiral and Polyakov loop susceptibilities.展开更多
基金Supported in part by the National Natural Science Foundation of China(11475085,11535005,11690030,11575069,11221504)the MoST of China 973-Project(2015CB856901)
文摘Conserved charge fluctuations can be used to probe the phase structure of strongly interacting nuclear matter in relativistic heavy-ion collisions. To obtain the characteristic signatures of the conserved charge fluctuations for the quantum chromodynamics(QCD) phase transition, we study the susceptibilities of dense quark matter up to eighth order in detail, using an effective QCD-based model. We studied two cases, one with the QCD critical end point(CEP) and one without owing to an additional vector interaction term. The higher order susceptibilities display rich structures near the CEP and show sign changes as well as large fluctuations. These can provide us information about the presence and location of the CEP. Furthermore, we find that the case without the CEP also shows a similar sign change pattern, but with a relatively smaller magnitude compared with the case with the CEP. Finally, we conclude that higher order susceptibilities of conserved charge can be used to probe the QCD phase structures in heavyion collisions.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10428510 and 10575058. One of the authors （Chang S.） thanks the High Energy Nuclear Physics Group of Tsinghua University for kind hospitality and Lianyi He and Xuewen Hao for helpful discussions.
文摘We investigate nucleon mass splitting at finite isospin chemical potential in the frame of the two-flavour Nambu-Jona-Lasinio model. It is analytically proven that in the phase with explicit isospin symmetry breaking, the proton mass decreases and the neutron mass increases linearly in the isospin chemical potential.
基金Supported in part by the MoST of China 973-Project(2015CB856901)the National Natural Science Foundation of China(11475085,11535005,11690030,11575069,11221504,11890711,11861131009)the Fundamental Research Funds for the Central Universities(020414380074,CCNU19QN054)
文摘We discuss the sign and energy dependence of second to tenth order susceptibilities of the baryon number,charge number, and strangeness for the analysis of critical conditions in heavy ion collisions in the LHC and RHIC by applying a modified Nambu-Jona-Lasinio model. This model is fitted to the quark condensate of the lattice QCD result at finite temperature and zero baryon chemical potential. The presence of a critical point made these susceptibilities deviate considerably from a Hadron-Resonance-Gas model that shows no criticality. The sign, magnitude, and energy dependence of these higher order fluctuations hint towards the existence and location of a critical point that could be discovered in future heavy ion collision experiments.
基金Supported by the National Natural Science Foundation of China(11475085,11535005,11690030)the National Major state Basic Research and Development(2016YFE0129300)
文摘The effective Lagrangian of a finite volume system should, in principle, depend on the system size. In the framework of the Nambu-Jona-Lasinio(NJL) model, by considering the influence of quark feedback on the effective coupling, we obtain a modified NJL model so that its Lagrangian depends on the volume. Based on the modified NJL model, we study the influence of finite volume on the chiral phase transition at finite temperature, and find that the pseudo-critical temperature of crossover is much lower than that obtained in the normal NJL model. This clearly shows that the volume dependent effective Lagrangian plays an important role in the chiral phase transitions at finite temperature.
文摘In a previous work, we proposed an extended Nmnbu-Jona-Lasinio （NJL） model including heavy quark flavors. In this work, we will calculate strong and radiative decays of vector mesons in this extended NJL model, including light p, w, K＊, θ and heavy D＊, D＊s, B＊, Bs＊.
基金Supported by the NSFC(11605254)Major State Basic Research Development Program in China(2015CB856903)
文摘We study the two-color QCD matter with two fundamental quark flavors using the chiral perturbation theory and the Nambu-Jona-Lasinio(NJL)model.The effective Lagrangian is derived in terms of mesons and baryons,i.e.diquarks.The low lying excitations lie in the extended SU(4)flavor symmetry space.We compute the leading order terms of the Lagrangian as a function of the baryon and axial isospin densities.After numerically solving the gap equations in the two-color NJL model,the phase diagram is obtained in the μ−ν5 plane.
基金The project supported by the Postdoctor Science Foundation the Nuclear Industry Foundation of China
文摘The transport equation for the Nambu-Jona-Lasinio (NJL) model isderived phenomenologically. The finite-temperature effective mass for the quarkis analysed, By means of the Chapman-Enskog method and hydrodynamic ap-proach the different transport coefficients for the NJL plasma are calculated tothe first order in the relaxation time.
文摘Based on an extended NJL model including heavy quark flavors, we calculate the form factors of pseudoscalar and vector mesons. After taking into account the vector-meson-dominance effect, which introduces a form factor correction to the quark vector coupling vertices, the form factors and electric radii of π^＋ and K^＋ pseudo-scalar mesons in the light flavor sector fit the experimental data well. The magnetic moments of the light vector mesons ρ^＋and K^＊＋are comparable with other theoretical calculations. The form factors in the light-heavy flavor sector are presented to compare with future experiments or other theoretical calculations.
文摘We propose an extended Nambu-Jona-Lasinio model to include heavy mesons with heavy quark symmetry.The quark current-current interaction is generalized to include the heavy quark currents. In order to comply with the heavy quark spin symmetry at the heavy quark limit,the dependence of the quark mass on the interaction strength is introduced. The light and heavy pseudo-scalar and vector mesons,their masses and the weak decay constants are calculated in the unified frame.
基金Supported by the Virtual Institute of the Helmholtz Association under the grant No.VH-Ⅵ-041.K.R.acknowledges partial support of the Gesellschaft für Schwerionenforschung (GSI)Committee for Scientific Research (KBN)
文摘We explore the NJL model with Polyakov loops for a system of three colors and two flavors within the mean-field approximation,where both chiral symmetry and confinement are taken into account.We focus on the phase structure of the model and study the chiral and Polyakov loop susceptibilities.
