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arXiv · hep-lat/0308010

Extending the Utility of Partially Quenched QCD

Stephen R. Sharpe·Ruth S. Van de Water
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Abstract

It has been proposed that partially quenched chiral perturbation theory can be used together with partially quenched lattice QCD to determine the low-energy constants of real QCD. We point out a complication of this approach and show how it can be resolved. Partial quenching changes the chiral symmetry group and introduces a new independent four-derivative operator. We explore the effects of this new operator. We describe tree-level scattering processes to which it contributes, and show how they can be used, in principle, to deterimine its unknown coefficient. We also calculate its lowest-order (one-loop) contribution to charged meson masses and decay constants. In addition, we present the form of the analytic next-to-next-to-leading order meson mass and decay constant corrections, which are needed for lattice fits.

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Stephen R. Sharpe, Ruth S. Van de Water. 2003-09-04. Extending the Utility of Partially Quenched QCD. https://doi.org/10.1016/s0920-5632(03)02544-1

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