Z0Production at thep¯pCollider and the Spin of the Gluon

It is suggested that an experimental verification of the relation $A_2=A_0$ ($A_i$ are the coefficients of the angular distribution of lepton pairs arising from decays of $Z^0$ produced at hadronic collisions) would be strong evidence for the vector nature of the spin of the gluon. The above relation $A_2=A_0$ is badly broken if the gluon coupling to quarks violates quark-helicity conservation.