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arXiv · 0707.0071

2+1 Flavor QCD simulated in the epsilon-regime in different topological sectors

P. Hasenfratz·D. Hierl·V. Maillart·F. Niedermayer·A. Schäfer·C. Weiermann·M. Weingart
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Abstract

We generated configurations with the parametrized fixed-point Dirac operator D_{FP} on a (1.6 fm)^4 box at a lattice spacing a=0.13 fm. We compare the distributions of the three lowest k=1,2,3 eigenvalues in the nu= 0,1,2 topological sectors with that of the Random Matrix Theory predictions. The ratios of expectation values of the lowest eigenvalues and the cumulative eigenvalue distributions are studied for all combinations of k and nu. After including the finite size correction from one-loop chiral perturbation theory we obtained for the chiral condensate in the MSbar scheme Sigma(2GeV)^{1/3}=0.239(11) GeV, where the error is statistical only.

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P. Hasenfratz, D. Hierl, V. Maillart, F. Niedermayer, A. Schäfer, C. Weiermann, M. Weingart. 2007-07-02. 2+1 Flavor QCD simulated in the epsilon-regime in different topological sectors. https://doi.org/10.1088/1126-6708/2009/11/100

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