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arXiv · 2111.01618

SU(2) gauge theory with $N_f=24$ quarks at non-zero mass

Jarno Rantaharju·Tobias Rindlisbacher·Kari Rummukainen·Ahmed Salami·Kimmo Tuominen
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Abstract

We study SU(2) gauge field theory with $N_f=24$ quarks. The theory is asymptotically non-free and, at vanishing quark mass, governed by a Gaussian fixed point at long distances. On the other hand, at non-zero quark mass the quarks are expected to decouple at long distances and the system behaves like confining pure gauge SU(2) theory. We study the mass spectrum of the theory as the quark mass is varied and obtain scaling laws for meson masses and string tension. We also measure the evolution of the coupling constant at non-zero quark mass with gradient flow method. We observe unambiguously the decoupling of the quarks with the associated change of evolution of the coupling constant.

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Jarno Rantaharju, Tobias Rindlisbacher, Kari Rummukainen, Ahmed Salami, Kimmo Tuominen. 2021-11-02. SU(2) gauge theory with $N_f=24$ quarks at non-zero mass. https://doi.org/10.22323/1.396.0025

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