Properties of phase transitions of the lattice SU(2) Higgs model

Abstract

We discuss the phase structure of the lattice-gauge--Higgs model for the gauge group SU(2) and Higgs fields in the fundamental representation with a dynamical radial mode. We find that the confinement-Higgs phase transition is of first order for small ${\ensuremath{\varphi}}^{4}$ coupling \ensuremath{\lambda} but weakens with increasing \ensuremath{\lambda}. Correlations of bound-state operators on the phase-transition point at \ensuremath{\lambda}=0.5, \ensuremath{\beta}=2.25 on a ${8}^{3}$\ifmmode\times\else\texttimes\fi{}16 lattice show a scalar state with the mass of 0.2 inverse lattice spacings and a four-times-heavier vector isotriplet.