Existence of IR SCFT for Sp(N) with one antisymmetric tensor and 2Nf fundamentals

Prove that the four-dimensional N=1 Sp(N) gauge theory with one rank-2 antisymmetric tensor A and 2Nf fundamental chiral multiplets Q (with superpotential W=0 and even number of fundamentals) flows to an interacting superconformal field theory in the infrared for all integers N and Nf satisfying 4 \le Nf < 2N+4.

Background

This Sp(N) Type I model features an antisymmetric tensor with even fundamentals. The authors note that for Nf<3 the flow is not to a unitary SCFT (runaway), and at Nf=3 the theory confines; for Nf≥4 a-maximization is well-behaved, leading to a conjecture of an interacting IR SCFT over the specified range.

This is consistent with known dynamical behaviors in low-flavor Sp gauge theories.