Direct Photon and Neutral Meson Production at Fermilab Fixed-Target Energies

Measurements of the production of high-pT direct photons and neutral mesons by a 515 GeV/c π− beam and 530 and 800 GeV/c proton beams in interactions with Be, Cu, and H2 targets are presented. Ratios of direct photon and π0 cross sections measured on the nuclear targets are compared with results from theoretical models. The direct-photon, π0, and π0π0 cross sections are compared with NLO pQCD calculations and expectations based on a phenomenological parton-kT model.