A Banks-Zaks fixed point is an IR-stable CFT describing long-distance behavior of QCD for certain parameters. The Lagrangian of QCD is L=∑aˉψa(iγ∂−ma)ψa−14F2 where color and spacetime indices have been suppressed. The flavor index a runs over Nf flavors of fermions.
This theory is asymptotically free (i.e., has a UV-stable fixed point) for Nf<332. For Nf just below that threshold, an IR-stable fixed point is visible in perturbation theory if the fermions are taken to be massless. This fixed point has been found to extend down at least to Nf∼12 in lattice studies.
Other theories can have Banks-Zaks fixed points, like SQCD.
Here are some lattice studies: https://arxiv.org/abs/0712.0609, https://arxiv.org/abs/0904.4662.