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arXiv · 1710.07020

Non-perturbative determination of improvement $b$-coefficients in $N_f=3$

Giulia Maria de Divitiis·Maurizio Firrotta·Jochen Heitger·Carl Christian Köster·Anastassios Vladikas
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Abstract

We present our preliminary results of the non-perturbative determination of the valence mass dependent coefficients $b_\mathrm{A}-b_\mathrm{P}$ and $b_\mathrm{m}$ as well as the ratio $Z_\mathrm{P} Z_\mathrm{m}/ Z_\mathrm{A}$ entering the flavour non-singlet PCAC relation in lattice QCD with $N_f=3$ dynamical flavours. We apply the method proposed in the past for quenched approximation and $N_f=2$ cases, employing a set of finite-volume ALPHA configurations with Schr\"odinger functional boundary conditions, generated with $O(a)$ improved Wilson fermions and the tree-level Symanzik-improved gauge action for a range of couplings relevant for simulations at lattice spacings of about $0.09 \,$fm and below.

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Giulia Maria de Divitiis, Maurizio Firrotta, Jochen Heitger, Carl Christian Köster, Anastassios Vladikas. 2017-10-19. Non-perturbative determination of improvement $b$-coefficients in $N_f=3$. https://arxiv.org/abs/1710.07020

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