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arXiv · 0910.4535

Mass anomalous dimension in SU(2) with two adjoint fermions

Abstract

We study SU(2) lattice gauge theory with two flavours of Dirac fermions in the adjoint representation. We measure the running of the coupling in the Schroedinger Functional (SF) scheme and find it is consistent with existing results. We discuss how systematic errors affect the evidence for an infrared fixed point (IRFP). We present the first measurement of the running of the mass in the SF scheme. The anomalous dimension of the chiral condensate, which is relevant for phenomenological applications, can be easily extracted from the running of the mass, under the assumption that the theory has an IRFP. At the current level of accuracy, we can estimate 0.05 < gamma < 0.56 at the IRFP.

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Francis Bursa, Luigi Del Debbio, Liam Keegan, Claudio Pica, Thomas Pickup. 2009-12-16. Mass anomalous dimension in SU(2) with two adjoint fermions. https://doi.org/10.1103/physrevd.81.014505

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