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A lattice study of the masses of singlet 0++ mesons

UKQCD Collaboration·A. Hart·C. McNeile·C. Michael·J. Pickavance
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Abstract

We compute the masses of the flavour singlet 0++ mesons using (n_f=2) unquenched lattice QCD with the Iwasaki and Wilson gauge actions. Both fermionic and glueball interpolating operators are used to create the states. The mass of the lightest 0++ meson is suppressed relative to the mass of the 0++ glueball in quenched QCD at an equivalent lattice spacing. We discuss two possible physical reasons for this.

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UKQCD Collaboration, A. Hart, C. McNeile, C. Michael, J. Pickavance. 2006-08-31. A lattice study of the masses of singlet 0++ mesons. https://doi.org/10.1103/physrevd.74.114504

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