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Inclusive π 0 and direct-photon cross sections in the kinematic range 3.5< p T <12 GeV/c with central rapidities (y cm ) are presented for 530 and 800 GeV/c proton beams and a 515 GeV/c π − beam incident on Be targets. Current Next-to-Leading-Order perturbative QCD calculations fail to adequately describe the data for conventional choices of scales. Kinematic distributions from these hard scattering events provide evidence that the interacting partons carry significant initial-state parton transverse momentum (k T ). Incorporating these k T effects phenomenologically greatly improves the agreement between calculations and the measured cross sections.

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K 0 S , Λ, Ξ, Ω and negative particle yields and transverse mass spectra have been measured at central rapidity in Pb-Pb and p-Pb collisions at 158 A GeV/c. Yields are studied as a function of the number of nucleons participating in the collision N part , which is estimated with the Glauber model. From p-Pb to Pb-Pb collisions the particle yields per participant increase substantially. The enhancement is more pronounced for multistrange particles, and exceeds an order of magnitude for the Ω. For a number of participants, N part , greater than 100, however, all yields per participant appear to be constant. To be published in Physics Letters B