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Overlap Fermions on a $20^4$ Lattice

K. F. Liu·S. J. Dong·F. X. Lee·J. B. Zhang
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Abstract

We report results on hadron masses, fitting of the quenched chiral log, and quark masses from Neuberger's overlap fermion on a quenched $20^4$ lattice with lattice spacing $a = 0.15$ fm. We used the improved gauge action which is shown to lower the density of small eigenvalues for $H^2$ as compared to the Wilson gauge action. This makes the calculation feasible on 64 nodes of CRAY-T3E. Also presented is the pion mass on a small volume ($6^3 \times 12$ with a Wilson gauge action at $β= 5.7$). We find that for configurations that the topological charge $Q \ne 0$, the pion mass tends to a constant and for configurations with trivial topology, it approaches zero possibly linearly with the quark mass.

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K. F. Liu, S. J. Dong, F. X. Lee, J. B. Zhang. 2000-11-17. Overlap Fermions on a $20^4$ Lattice. https://doi.org/10.1016/s0920-5632(01)00908-2

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