Multi-selfoverlap-ensemble Monte Carlo method for lattice proteins and heteropolymers

A new Monte Carlo method for lattice heteropolymers is proposed. It is a tw o variable extention of the multicanonical ensemble method, which contains some portion of unphysical self-overlapping conformations. Correct canonica l ensemble of the self-avoiding chain is obtained by reweighting of the his togram after the simulation is done. The performance of the method is super ior to the standard multicanonical ensemble. Applications to long lattice p roteins are presented.