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arXiv · 1812.02727

Partial compositeness and baryon matrix elements on the lattice

Venkitesh Ayyar·Thomas DeGrand·Daniel C. Hackett·William I. Jay·Ethan T. Neil·Yigal Shamir·Benjamin Svetitsky
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Abstract

Partial compositeness is a mechanism for the generation of fermion masses which replaces a direct Higgs coupling to the fermions by a linear mixing with heavy composite partners. We present the first calculation of the relevant matrix element in a lattice model which is very close to a candidate theory containing a composite Higgs boson and a partially composite top quark. Specifically, our model is an SU(4) gauge theory coupled to dynamical fermions in the fundamental and two-index antisymmetric (sextet) representations. The matrix element we obtain is small and hence our result disfavors the scenario of obtaining a realistic top mass in this model.

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Venkitesh Ayyar, Thomas DeGrand, Daniel C. Hackett, William I. Jay, Ethan T. Neil, Yigal Shamir, Benjamin Svetitsky. 2018-12-06. Partial compositeness and baryon matrix elements on the lattice. https://doi.org/10.1103/physrevd.99.094502

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