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arXiv · 2304.11729

Infrared fixed point and anomalous dimensions in a composite Higgs model

Anna Hasenfratz·Ethan T. Neil·Yigal Shamir·Benjamin Svetitsky·Oliver Witzel
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Abstract

We use lattice simulations and the continuous renormalization-group method, based on the gradient flow, to study a candidate theory of composite Higgs and a partially composite top. The model is an SU(4) gauge theory with four Dirac fermions in each of the fundamental and two-index antisymmetric representations. We find that the theory has an infrared fixed point at $g^2 \simeq 15.5$ in the gradient flow scheme. The mass anomalous dimension of each representation is large at the fixed point. On the other hand, the anomalous dimensions of top-partner operators do not exceed 0.5 at the fixed point. This may not be large enough for a phenomenologically successful model of partial compositeness.

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Anna Hasenfratz, Ethan T. Neil, Yigal Shamir, Benjamin Svetitsky, Oliver Witzel. 2023-04-23. Infrared fixed point and anomalous dimensions in a composite Higgs model. https://doi.org/10.1103/physrevd.107.114504

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