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arXiv · 1711.05299

Spectroscopy of the BSM sextet model

Zoltan Fodor·Kieran Holland·Julius Kuti·Daniel Nogradi·Chik Him Wong
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Abstract

As part of our ongoing lattice study of SU(3) gauge theory with two flavors of fermions in the two-index symmetric representation (the sextet model), we present the current status of the pseudoscalar particle spectrum. We use a mixed action approach based on the gradient flow to control lattice artifacts, allowing a simultaneous extrapolation to the chiral and continuum limits. We find strong evidence that the pseudoscalar is a Goldstone boson state, with spontaneously broken chiral symmetry and a non-zero Goldstone decay constant in the chiral limit. In agreement with our study of the gauge coupling $\beta$ function, we find the sextet model appears to be a near-conformal gauge theory and serves as a prototype of the composite Higgs BSM template.

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Zoltan Fodor, Kieran Holland, Julius Kuti, Daniel Nogradi, Chik Him Wong. 2017-11-14. Spectroscopy of the BSM sextet model. https://doi.org/10.1051/epjconf%2F201817508014

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