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arXiv · 1502.07773

Non-perturbative improvement and renormalization of the axial current in N_f=3 lattice QCD

John Bulava·Michele Della Morte·Jochen Heitger·Christian Wittemeier
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Abstract

We report on a non-perturbative computation of the renormalization factor Z_A of the axial vector current in three-flavour O(a) improved lattice QCD with Wilson quarks and tree-level Symanzik improved gauge action and also recall our recent determination of the improvement coefficient c_A. Our normalization and improvement conditions are formulated at constant physics in a Schr\"odinger functional setup. The normalization condition exploits the full, massive axial Ward identity to reduce finite quark mass effects in the evaluation of Z_A and correlators with boundary wave functions to suppress excited state contributions in the pseudoscalar channel.

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John Bulava, Michele Della Morte, Jochen Heitger, Christian Wittemeier. 2015-02-26. Non-perturbative improvement and renormalization of the axial current in N_f=3 lattice QCD. https://arxiv.org/abs/1502.07773

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