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arXiv · 1701.04666

The gradient flow running coupling in SU(2) gauge theory with $N_f=8$ fundamental flavors

Viljami Leino·Jarno Rantaharju·Teemu Rantalaiho·Kari Rummukainen·Joni M. Suorsa·Kimmo Tuominen
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Abstract

We study the evolution of the coupling in SU(2) gauge field theory with $N_f=8$ fundamental fermion flavors on the lattice. This model is expected to have an infrared fixed point at high coupling. We use HEX-smeared Wilson-clover action, and measure the gradient flow running coupling with Dirichlet boundary conditions. Extrapolating our results to continuum, we find an infrared fixed point at $g^2=8.24(59)^{+0.97}_{-1.64}$, with statistical and systematic error estimates. We also measure the anomalous dimension of the quark mass operator, and find its value at the fixed point $\gamma \approx 0.15 \pm 0.02$.

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Viljami Leino, Jarno Rantaharju, Teemu Rantalaiho, Kari Rummukainen, Joni M. Suorsa, Kimmo Tuominen. 2017-01-17. The gradient flow running coupling in SU(2) gauge theory with $N_f=8$ fundamental flavors. https://doi.org/10.1103/physrevd.95.114516

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