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arXiv · hep-lat/0401004

A partially quenched analysis of the eta-eta' system in N_f=2 QCD

H. Neff·Th. Lippert·J. Negele·K. Schilling
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Abstract

We report on a first, comprehensive partially quenched study of the eta-eta' problem, based on SESAM configurations on a 16^3x32 lattice at beta=5.6 QCD with two (mass degenerate) active sea quark flavours. By means of the spectral approximation of the two-loop (hairpin) diagrams, we find clear plateau formation in the effective masses which enables us both to determine the eta-eta' mass matrix and the alpha-parameter in the effective chiral Lagrangian for the flavour singlet sector, alpha=0.028 +- 0.013.

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H. Neff, Th. Lippert, J. Negele, K. Schilling. 2004-01-02. A partially quenched analysis of the eta-eta' system in N_f=2 QCD. https://doi.org/10.1016/s0920-5632(03)02535-0

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