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A Study of the 't Hooft Model with the Overlap Dirac Operator

F. Berruto·L. Giusti·C. Hoelbling·C. Rebbi
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Abstract

We present the results of an exploratory numerical study of two dimensional QCD with overlap fermions. We have performed extensive simulations for U(N_c) and SU(N_c) color groups with N_c=2, 3, 4 and coupling constants chosen to satisfy the 't Hooft condition g^2 N_c =const=4/3. We have computed the meson spectrum and decay constants, the topological susceptibility and the chiral condensate. For U(N_c) gauge groups, our results indicate that the Witten-Veneziano relation is satisfied within our statistical errors and that the chiral condensate for N_f=1 is compatible with a non-zero value. Our results exhibit universality in N_c and confirm once more the excellent chiral properties of the overlap-Dirac operator.

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F. Berruto, L. Giusti, C. Hoelbling, C. Rebbi. 2002-01-07. A Study of the 't Hooft Model with the Overlap Dirac Operator. https://doi.org/10.1103/physrevd.65.094516

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