Five-dimensional CFTs from the $ε$-expansion

Abstract

We look for UV fixed points of non-abelian $SU(n_c)$ gauge theories in $4+2ε$ dimensions with $n_f$ Dirac fermions in the fundamental representation, using the available five-loop $\overline{\rm MS}$ $β$-function and employing Padé-Borel resummation techniques and Padé approximants to the series expansion in $ε$. We find evidence for a $5d$ UV-fixed point for $SU(2)$ theories with $n_f\leq 4$. We also compute the anomalous dimensions $γ$ and $γ_g$ of respectively the fermion mass bilinear and the gauge kinetic term operator at the UV fixed point.