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arXiv · 1906.03445

Non-perturbative determination of improvement coefficients b_m and b_A-b_P and normalisation factor Z_m*Z_P/Z_A with N_f=3 Wilson fermions

Giulia Maria de Divitiis·Patrick Fritzsch·Jochen Heitger·Carl Christian Koester·Simon Kuberski·Anastassios Vladikas
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Abstract

We determine non-perturbatively the normalisation constant Z_m*Z_P/Z_A as well as the Symanzik coefficients b_m and b_A-b_P, required in O(a) improved quark mass renormalisation with Wilson fermions. The strategy underlying their computation involves simulations in N_f=3 QCD with O(a) improved massless sea and non-degenerate valence quarks in the finite-volume Schroedinger functional scheme. Our results, which cover the typical gauge coupling range of large-volume N_f=2+1 QCD simulations with Wilson fermions at lattice spacings below 0.1 fm, are of particular use for the non-perturbative calculation of O(a) improved renormalised quark masses.

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Giulia Maria de Divitiis, Patrick Fritzsch, Jochen Heitger, Carl Christian Koester, Simon Kuberski, Anastassios Vladikas. 2019-06-08. Non-perturbative determination of improvement coefficients b_m and b_A-b_P and normalisation factor Z_m*Z_P/Z_A with N_f=3 Wilson fermions. https://doi.org/10.1140/epjc%2Fs10052-019-7287-1

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