Testing asymptotic scaling and nonabelian symmetry enhancement

We determine some points on the finite size scaling curve for the correlation length in the two-dimensional O(3) and icosahedron spin models. The Monte Carlo data are consistent with the two models possessing the same continuum limit. The data also suggest that the continuum scaling curve lies above the estimate of Kim [Phys. Rev. Lett. 70 (1993) 1735] and Caracciolo et al. [Phys. Rev. Lett. 75 (1995) 1891] and thus leads to larger thermodynamic values of the correlation length than previously reported.