title: Interquark potential with finite quark mass from lattice QCD.
abstract: We present an investigation of the interquark potential determined from the q ̄q Bethe-Salpeter (BS) amplitude for heavy quarkonia in lattice QCD. The q ̄q potential at finite quark mass m(q) can be calculated from the equal-time and Coulomb gauge BS amplitude through the effective Schrödinger equation. The definition of the potential itself requires information about a kinetic mass of the quark. We then propose a self-consistent determination of the quark kinetic mass on the same footing. To verify the proposed method, we perform quenched lattice QCD simulations with a relativistic heavy-quark action at a lattice cutoff of 1/a≈2.1  GeV in a range 1.0≤m(q)≤3.6 GeV. Our numerical results show that the q ̄q potential in the m(q)→∞ limit is fairly consistent with the conventional one obtained from Wilson loops. The quark-mass dependence of the q ̄q potential and the spin-spin potential are also examined.
authors.affiliation: Department of Physics, The University of Tokyo, Hongo 7-3-1, Tokyo 113-0033, Japan. kawanai@nt.phys.s.u-tokyo.ac.jp
authors.forename: Taichi
authors.initials: T
authors.lastname: Kawanai
authors.forename: Shoichi
authors.initials: S
authors.lastname: Sasaki