A test of the Kugo-Ojima confinement criterion by lattice Landau gauge QCD simulations

The first test of the Kugo-Ojima colour confinement criterion by the lattice Landau gauge QCD simulation is performed. The parameter u which is expected to be -1\delta^a_b in the continuum theory was found to be -0.7\delta^a_b in the strong coupling region. The data is analyzed in connection with the theory of Zwanziger. In the weak coupling region, the expectation value of the horizon function is negative or consistent to 0.