Composite reweighting SU(2) QCD at finite temperature

The Glasgow reweighting method is evaluated for SU(2) lattice gauge theory at nonzero mu and finite T. We establish that the 'overlap problem' of SU(3) measurements, in which the transition points determined from thermodynamic observables have an unphysical dependence on the value of g used to generate ensembles for reweighting, persists for SU(2). By combining the information from different lattice ensembles we alleviate sampling bias in the fugacity expansion, and identify the Lee-Yang zeros associated with the transition to a high density phase that can plausibly be associated with diquark condensation. We also confirm the existence of a line of first order transitions above a critical point in the T-p phase plane previously predicted by effective chiral lagrangian calculations. (C) 2002 Elsevier Science B.V. All rights reserved.