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arXiv · 1004.1004

Conformal or Walking? Monte Carlo renormalization group studies of SU(3) gauge models with fundamental fermions

Anna Hasenfratz
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Abstract

Strongly coupled gauge systems with many fermions are important in many phenomenological models. I use the 2-lattice matching Monte Carlo renormalization group method to study the fixed point structure and critical indexes of SU(3) gauge models with 8 and 12 flavors of fundamental fermions. With an improved renormalization group block transformation I am able to connect the perturbative and confining regimes of the N_f=8 flavor system, thus verifying its QCD-like nature. With N_f=12 flavors the data favor the existence of an infrared fixed point and conformal phase, though the results are also consistent with very slow walking. I measure the anomalous mass dimension in both systems at several gauge couplings and find that they are barely different from the free field value.

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Anna Hasenfratz. 2010-04-07. Conformal or Walking? Monte Carlo renormalization group studies of SU(3) gauge models with fundamental fermions. https://doi.org/10.1103/physrevd.82.014506

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