We construct a family of examples of pairs of 4d N=2 SCFTs whose graded Coulomb branch dimensions, Weyl-anomaly coefficients and flavour symmetry algebras and levels coincide, but which are nonetheless distinct SCFTs. The difference (detectable by the superconformal index) can occur at arbitrarily high order. We argue that it is, however, reflected in a difference in the global form of the flavour symmetry groups.
@article{arxiv.2012.15249,
title = {Distinquishing 4d N=2 SCFTs},
author = {Jacques Distler and Behzat Ergun and Ali Shehper},
journal= {arXiv preprint arXiv:2012.15249},
year = {2021}
}