  We describe numerical calculation results for the probability distribution of
the value of the monopole creation operator in the SU(2) lattice gluodynamics.
We work in the maximal abelian projection. It occurs that at low temperatures,
below the deconfinement phase transition, the maximum of the distribution is
shifted from zero, which means that the effective constraint potential is of
the Higgs type. Above the phase transition the minimum of the potential (the
maximum of the monopole field distribution) is at the zero value of the
monopole field. This fact confirms the existence of the abelian monopole
condensate in the confinement phase of lattice gluodynamics, and agrees with
the dual superconductor model of the confining vacuum.
