Dear Prof. Matthias Troyer,

I would like to investigate the local magnetic order and its contribution to the internal energy for the classical ferromagnetic 3D Heisenberg model above the critical temperature. Is it possible to define therefore some correlation function in alps or are they eventually already defined? Is it possible to link the mean 'cluster size' output to the local magnetic order (when using cluster updates within the classical MC)?

Since I'm a newbie in the MC, let me ask: there is a finite contribution to the internal energy above the critical temperature, is this only due to the finite tail of the (total) magnetization or is this due to local order, still existing in the system above Tc?

Many, many thanks for your help :), best, Fritz

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