Download presentation
Presentation is loading. Please wait.
Published byPhoebe Park Modified over 9 years ago
1
1 Heavy quark potential in full QCD lattice simulations at finite temperature Yuu Maezawa (The Univ. of Tokyo) Tsukuba-Tokyo collaboration Univ. of Tsukuba S. Aoki K. Kanaya Y. Taniguchi E. Ejiri T. Hatsuda N. Ishii N. Ukita The Univ. of Tokyo
2
2 Contents Introduction Formalism of lattice QCD Simulation results Summary Full-QCD action on lattice Free energy and potential on lattice Potential using two-flavor Wilson quarks Comparison with perturbation theory at T > Tc Comparison with KS fermion
3
3 Introduction Behavior of string breaking at Behavior of screening effect at Behavior of heavy quark potential at finite T String breaking at Screening effect at Lattice simulation using full-QCD action (2-flavor)
4
4 Formalism of lattice QCD : link variable Gluon field Quark field Kogut-Susskind(KS) fermion action Wilson fermion action Simulation time KS fermion < Wilson fermion × 10 We use the Wilson fermion action. Compare with KS fermion action KS fermion trick
5
5 Free energy and Potential on a lattice McLerran, Svetitsky, PRD 24 (1981) 450 Polyakov loop: Free energy of the quark-antiquark pair Static charged quark Quark- antiquark potential
6
6 Projection operator and Nadkarni, PRD 34 (1986) 3904 Quark-quark potential Separation to each channel after the Coulomb gauge fixing
7
7 Simulation results Lattice size: Gauge action: RG improved action Fermion action: improved Wilson action (2-flavor) Quark mass: Temperature: Configuration: ≒ 500 confs. Gauge fixing: Coulomb gauge Parameters
8
8 Quark-antiquark potential at T < Tc String breaking Shot range: agree with V (r,T =0) Long range: string breaking
9
9 1 c channel: attractive force 8 c channel: repulsive force Screening effect Quark-antiquark potential at T > Tc
10
10 3 c channel: attractive force 6 c channel: repulsive force Quark-quark potential at T > Tc
11
11 Screening effect at. Screening effect Yukawa type potential : Casimir factor Fitting the potentials of each channel regarding and as free parameters.
12
12 At high T, potentials of each channel can be written by the same parameters: and. Results of and.
13
13 Relation between and. Effective running coupling determined from reproduces. Effective running coupling Screening mass
14
14 Next-to-leading order perturbation Rebhan, PRD 48 (1993) 48 2-loop running coupling parameterization Lattice screening mass is well reproduced by the NLO-type screening mass > 0 on the lattice vs. perturbative screening mass
15
15 Comparison with KS fermion Kaczmarek and Zantow, PRD 71 (2005) 114510 KS fermion with Systematic error due to the difference of action may be as large as 20% in the screening mass. ~ KS fermion Quench
16
16 Heavy quark potential Lattice QCD simulation using 2-flavor Wilson fermion action Summary String breaking at, screening effect at At, potentials are fitted by At high T, potentials of each channel can be written by the same parameters: and. Effective running coupling determined from reproduces. Lattice screening mass is well reproduced by the NLO-type screening mass. Comparison with KS fermion action Systematic error is as large as 20%
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.