MONTE-CARLO STUDY OF PURE-PHASE CUMULANTS OF 2D Q-STATE POTTS MODELS

We performed Monte-Carlo simulations of the two-dimensional q-state Po tts model with q=10, 15, and 20 to study the energy and magnetization cumulants in the ordered and disordered phase at the first-order trans ition point beta(t). By using very large systems of size 300 x 300, 12 0 x 120, and 80 x 80 for q = 10, 15, and 20, respectively, our numeric al estimates provide practically (up to unavoidable, but very small st atistical errors) exact results which can serve as a useful test of re cent resummed large-q expansions for the energy cumulants by Bhattacha rya et al. (J. Phys. France 7 (1997) 81). Up to the third-order cumula nt and down to q = 10 we obtain very good agreement, and also the high er-order estimates are found to be compatible.