  We present the results of the numerical calculation of the probability
distribution of the value of the monopole creation operator in $SU(2)$ lattice
gluodynamics. We work in the maximal abelian projection. It occurs that at the
low temperature, 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 is the direct proof of the existence of the abelian
monopole condensate in the confinement phase of the gluodynamics, which
confirms the dual superconductor model of the confining vacuum.
