N N =1 Deformations and RG flows of N N =2 SCFTs, part II: non-principal deformations

We continue to investigate the N = 1 deformations of four-dimensional N = 2 superconformal field theories (SCFTs) labeled by a nilpotent element of the flavor symmetry [1]. This triggers a renormalization group (RG) flow to an N = 1 SCFT. We systematically analyze all possible deformations of this type for certain classes of N = 2 SCFTs: conformal SQCDs, generalized Argyres-Douglas theories and the E 6 SCFT. We find a number of examples where the amount of supersymmetry gets enhanced to N = 2 at the end point of the RG flow. Most notably, we find that the SU(N ) and Sp(N ) conformal SQCDs can be deformed to flow to the Argyres-Douglas (AD) theories of type (A 1 , D 2N −1) and (A 1 , D 2N ) respectively. This RG flow therefore allows us to compute the full superconformal index of the (A 1 , D N ) class of AD theories. Moreover, we find an infrared duality between N = 1 theories where the fixed point is described by an N = 2 AD theory. We observe that the classes of examples that exhibit supersymmetry enhancement saturate certain bounds for the central charges implied by the associated two-dimensional chiral algebra.