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arXiv · hep-lat/0201009

Flavour Singlet Mesons in Full QCD on the Lattice

K. Schilling·H. Neff·N. Eicker·Th. Lippert·J. W. Negele
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Abstract

We apply spectral methods to compute the OZI-rule suppressed loop-loop correlators in the pseudoscalar meson flavour singlet channel. Using SESAM configurations (obtained with two degenerate sea quark flavours on 16x16x16x32 lattices at beta = 5.6 with standard Wilson action), we find for the first time clear evidence for mass plateau formation in the eta' channel of this theory. As a consequence, we observe a clear signal of a mass gap persistent under chiral extrapolation. This sets the stage for a more realistic two-channel approach, where partially quenched strange quarks would be included, in addition to u, d sea quarks.

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K. Schilling, H. Neff, N. Eicker, Th. Lippert, J. W. Negele. 2002-01-07. Flavour Singlet Mesons in Full QCD on the Lattice. https://doi.org/10.1016/s0920-5632(02)01384-1

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