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arXiv · 1711.06017

A tmQCD mixed-action approach to flavour physics

Gregorio Herdoíza·Carlos Pena·David Preti·José Ángel Romero·Javier Ugarrio
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Abstract

We discuss a mixed-action approach in which sea quarks are regularised using non-perturbatively ${\rm O}(a)$ improved Wilson fermions, while a fully-twisted tmQCD action is used for valence quarks. In this setup, automatic ${\rm O}(a)$ improvement is preserved for valence observables, apart from small residual ${\rm O}(a)$ effects from the sea. A strategy for matching sea and valence is set up, and carried out for $N_\mathrm{f}=2+1$ CLS ensembles with open boundary conditions at several simulation points. The scaling of basic light-quark observables such as the pseudoscalar meson decay constant is studied, as well as the isospin splitting of pseudoscalar meson masses.

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Gregorio Herdoíza, Carlos Pena, David Preti, José Ángel Romero, Javier Ugarrio. 2017-11-16. A tmQCD mixed-action approach to flavour physics. https://doi.org/10.1051/epjconf/201817513018

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