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arXiv · hep-lat/9711020

The eta-prime propagator in quenched QCD

W. Bardeen·A. Duncan·E. Eichten·S. Perrucci·H. Thacker
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Abstract

The calculation of the eta-prime hairpin diagram is carried out in the modified quenched approximation (MQA) in which the lattice artifact which causes exceptional configurations is removed by shifting observed poles at kappa<kappa_c in the quark propagators to the critical value of hop ping parameter. By this method, the eta-prime propagator can be accurately calculated even for very light quark mass. A determination of the topological susceptibility for quenched QCD is also obtained, using the fermionic method of Smit and Vink to calculate winding numbers.

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W. Bardeen, A. Duncan, E. Eichten, S. Perrucci, H. Thacker. 1997-11-12. The eta-prime propagator in quenched QCD. https://doi.org/10.1016/s0920-5632(97)00718-4

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