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arXiv · hep-lat/0401015

Discretisation effects in the topological susceptibility in lattice QCD

UKQCD·QCDSF Collaborations·:·A. Hart
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Abstract

We study the topological susceptibility, chi, in QCD with two quark flavours using lattice field configurations that have been produced with an O(a)-improved clover quark action. We find clear evidence for the expected suppression at small quark mass, m_q, and examine the variation of $χ$ with this mass and the lattice spacing, a. A joint continuum and chiral extrapolation yields good agreement with theoretical expectations as (a, m_q) -> 0. A moderate increase in autocorrelation is observed on the more chiral ensembles, but within large statistical errors. Finite volume effects are negligible for Leutwyler-Smilga parameter x_LS > 10, and no evidence for a nearby phase transition is observed.

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BibTeXRIS

UKQCD, QCDSF Collaborations, :, A. Hart. 2004-01-09. Discretisation effects in the topological susceptibility in lattice QCD. https://doi.org/10.1103/physrevd.69.074510

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