Amplitude universality and confluent corrections to scaling for Ising models

Abstract

Using existing series for spin-$s$ Ising models and for continuous-spin Ising models, we have verified the universality of the ratio of the amplitudes associated with the leading confluent corrections to the susceptibility and to the correlation length. We have, thereby, tested the universality of the subcritical part of the correlation function, of which the universality of the amplitude ratio in question is a direct consequence.