Finite density phase transition of QCD with N{sub f}=4 and N{sub f}=2 using canonical ensemble method

Journal Article · Wed Sep 01 00:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.82.054502· OSTI ID:21421050

Anyi, Li ^[1]; Alexandru, Andrei ^[2]; Liu, Keh-Fei ^[3]; Xiangfei, Meng ^[4]

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1. Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506 (United States) and Department of Physics, Duke University, Durham, North Carolina 27708 (United States)
2. Physics Department, George Washington University, Washington, D.C. 20052 (United States)
3. Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506 (United States)
4. Department of Physics, Nankai University, Tianjin 300071 (China)

In a progress toward searching for the QCD critical point, we study the finite density phase transition of N{sub f}=4 and 2 lattice QCD at finite temperature with the canonical ensemble approach. We develop a winding number expansion method to accurately project out the particle number from the fermion determinant which greatly extends the applicable range of baryon number sectors to make the study feasible. Our lattice simulation was carried out with the clover fermions and improved gauge action. For a given temperature, we calculate the baryon-chemical potential from the canonical approach to look for the mixed phase as a signal for the first-order phase transition. In the case of N{sub f}=4, we observe an 'S-shape' structure in the chemical potential-density plane due to the surface tension of the mixed phase in a finite volume which is a signal for the first-order phase transition. We use the Maxwell construction to determine the phase boundaries for three temperatures below T{sub c}. The intersecting point of the two extrapolated boundaries turns out to be at the expected first-order transition point at T{sub c} with {mu}=0. This serves as a check for our method of identifying the critical point. We also studied the N{sub f}=2 case, but do not see a signal of the mixed phase for temperature as low as 0.83T{sub c}.

• OSTI ID: 21421050
• Journal Information: Physical Review. D, Particles Fields, Vol. 82, Issue 5; Other Information: DOI: 10.1103/PhysRevD.82.054502; (c) 2010 American Institute of Physics; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYON NUMBER
BARYONS
COMPUTERIZED SIMULATION
CRITICAL TEMPERATURE
DENSITY
EXPANSION
LATTICE FIELD THEORY
PARTICLES
PHASE TRANSFORMATIONS
QUANTUM CHROMODYNAMICS
SURFACE TENSION
CONSTRUCTIVE FIELD THEORY
ELEMENTARY PARTICLES
FERMIONS
FIELD THEORIES
HADRONS
PHYSICAL PROPERTIES
QUANTUM FIELD THEORY
SIMULATION
SURFACE PROPERTIES
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE