Static Qˉ\bar{Q}-QQ Potential from Nf=2N_f=2 Dynamical Domain-Wall QCD

We calculate the static quark and anti-quark potential both in quenched and two-flavor dynamical quark lattice QCD using DBW2 gauge and domain-wall quark actions. Lattice spacings from Sommer scale are determined. We find (i) mixing of excited states is different in between quenched and dynamical, (ii) lattice spacing $a_{r_0}\sim a_{m_{\rho}}$ in dynamical and (iii) coefficient of Coulomb term being $\alpha_{N_f=0}<\alpha_{N_f=2}$ at $a^{-1}\sim$ 2 GeV.Comment: Talk presented at Lattice2004(spectrum), Fermilab, June 21-26, 200

B_K from Two-flavor Dynamical Domain Wall Fermions

We report preliminary results from an ongoing calculation of $B_K$ for $N_f=2$ dynamical QCD with domain wall fermions. Simulations have been done with three dynamical quark masses on $16^3 \times 32$ volumes with $L_s = 12$, where the lattice spacing is $a^{-1} = 1.81(6)$ GeV. Using measurements on $\sim 70$ lattices for each dynamical mass and extrapolating \mdyn=\mval to the kaon point, we find $B_K^{\rm \bar{MS}}(\mu=2{\rm GeV}) = 0.503(20)$.Comment: Lattice2003(matrix), 3 pages, 2 figure

Lattice Gross-Neveu model with domain-wall fermions

We investigate the two-dimensional lattice Gross-Neveu model, using the domain-wall fermion formulation, as a toy model of lattice QCD. We study features of the phase diagram related to the mechanism of chiral symmetry restoration, and find that the parity-broken phase (Aoki phase) exists for finite extent in the extra dimension ($N_s$). We also find that O(a) scaling violation terms vanishes in the limit of $N_s\to\infty$.Comment: LATTICE99 (Chiral Fermions), 3 pages, 4 figure

Improving chiral property of domain-wall fermions by reweighting method

The reweighting method is applied to improve the chiral property of domain-wall fermions. One way to achieve this is to enlarge $L_s$, the size of fifth dimension, which controls the size of the induced chiral symmetry breaking. While this is a type of reweighting method for shifting the action parameter, it seems non-trivial since this reweighting means change of the five dimensional lattice volume. In this report, we address issues in this direction of reweighting and evaluate its effectiveness.Comment: 7 pages, talk presented at The XXVII International Symposium on Lattice Field Theory, July 26-31 2009, Peking University, Beijing, Chin