Production of. pi. sup 0 mesons at high p sub T in. pi. sup minus Be and p Be collisions at 500 GeV/ c

We present new measurements of {pi}{sup 0} production at high transverse momenta ({ital p}{sub {ital T}}) for {pi}{sup {minus}} and {ital p} interactions on Be and Cu targets at 500 GeV/{ital c}. The observed dependence of the yields as a function of {ital p}{sub {ital T}} and rapidity ({ital y}) is compared with expectations from leading-log QCD over a kinematic range in which the inclusive cross sections fall by more than 4 orders of magnitude.