Three-dimensional lattice U(1) gauge-Higgs model at low mH

We study the non-compact version of the U(1) gauge-Higgs model in three dimensions for mH = 30 GeV. We found that, using this formulation, rather modest lattices approach quite well the infinite volume behaviour.The phase transition is first order, as expected for this Higgs mass. The latent heat (in units of T4cr) is compatible with the predictions of the two-loop effective potential; it is an order of magnitude less than the corresponding SU(2) value. The transition temperature and 〈φ*φ〉 in units of the critical temperature are also compatible with the perturbative results.