Analytical Calculation for the Fixed Length Lattice SU/(2)-Higgs Model

Abstract：

The phase diagram of the lattice system of the SU(2) gauge field coupled with the fixed length Higgs field in the fundamental representation has been calculated analytically to the fourth order of the cumulant expansion. The variational parameters have been determined by scanning method. The obtained phase diagram is in fine agreement with the Monte Carlo result. The calculation also has been made for the Polyakov line <L> of the SU(2) Higgs and the pure SU(2) models at finite temperature (N_τ=1). The best (up to now) approximate analytical result β_c for the pure SU(2) model is obtained.