本学期学术活动

付伟杰:QCD phase structure at finite temperature and density within the functional renormalization group approach

2019-12-05    点击:

报告题目:QCD phase structure at finite temperature and density within the functional renormalization group approach

报 告 人:付伟杰,大连理工大学教授

报告时间:2019-12-05 14:00

报告地点:物理系理科楼B406

报告摘要:In this talk I will present the recent studies of the phase structure of QCD for Nf=2 and Nf=2+1 dynamical quark flavours at finite temperature and baryon chemical potential. It emerges dynamically from the underlying fundamental interactions between quarks and gluons. To this end, starting from the perturbative high-energy regime, we systematically integrate-out quantum fluctuations towards low energies by using the functional renormalization group. By dynamically hadronizing the dominant interaction channels responsible for the formation of light mesons and quark condensates, we are able to extract the phase diagram for μB/T≤6. We find a critical endpoint at (T_CEP,μB_CEP)=(107,635)MeV. The curvature of the phase boundary at small chemical potential is κ=0.0142(2), computed from the renormalized light chiral condensate Δ_{l,R}. Furthermore, we find indications for an inhomogeneous regime in the vicinity and above the chiral transition for μB≥417 MeV. Where applicable, our results are in very good agreement with the most recent lattice results. We also compare to results from other functional methods and phenomenological freeze-out data. This indicates that a consistent picture of the phase structure at finite baryon chemical potential is beginning to emerge. The systematic uncertainty of our results grows large in the density regime around the critical endpoint and I will discuss necessary improvements of our current approximation towards a quantitatively precise determination of QCD phase diagram.

Ref. Wei-jie Fu, Jan M. Pawlowski, Fabian Rennecke, arXiv:1909.02991 [hep-ph]