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arXiv · 2111.14710

Gradient flow scale-setting with $N_f=2+1+1$ Wilson-clover twisted-mass fermions

Constantia Alexandrou·Simone Bacchio·Georg Bergner·Petros Dimopoulos·Jacob Finkenrath·Roberto Frezzotti·Marco Garofalo·Bartosz Kostrzewa·Giannis Koutsou·Peter Labus·Francesco Sanfilippo·Silvano Simula·Martin Ueding·Carsten Urbach·Urs Wenger
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Abstract

We present a determination of the gradient flow scales $w_0$, $\sqrt{t_0}$ and $t_0/w_0$ in isosymmetric QCD, making use of the gauge ensembles produced by the Extended Twisted Mass Collaboration (ETMC) with $N_f=2+1+1$ flavours of Wilson-clover twisted-mass quarks including configurations close to the physical point for all dynamical flavours. The simulations are carried out at three values of the lattice spacing and the scale is set through the PDG value of the pion decay constant, yielding $w_0=0.17383(63)$ fm, $\sqrt{t_0}=0.14436(61)$ fm and $t_0/w_0=0.11969(62)$ fm. Finally, fixing the kaon mass to its isosymmetric value, we determine the ratio of the kaon and pion leptonic decay constants to be $f_K/f_{\pi}=1.1995(44)$.

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Constantia Alexandrou, Simone Bacchio, Georg Bergner, Petros Dimopoulos, Jacob Finkenrath, Roberto Frezzotti, Marco Garofalo, Bartosz Kostrzewa, Giannis Koutsou, Peter Labus, Francesco Sanfilippo, Silvano Simula, Martin Ueding, Carsten Urbach, Urs Wenger. 2021-11-29. Gradient flow scale-setting with $N_f=2+1+1$ Wilson-clover twisted-mass fermions. https://arxiv.org/abs/2111.14710

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