Nuclear enhancement of π0 and η mesons produced at large transverse momenta

The authors have measured the large-p/sub T/ inclusive cross sections for ..pi../sup 0/ and eta production near 90/sup 0/ in the center-of-mass system in 200-GeV/c ..pi../sup +/ and proton collisions with beryllium, carbon, and aluminum targets. The cross section for both ..pi../sup 0/ and eta mesons rises with increasing nucleon number (A) of the target nucleus as A/sup ..cap alpha../, with ..cap alpha..>1. The ratio of the ..pi../sup 0/ yield in pA collisions to that in ..pi../sup +/A collisions decreases with increasing p/sub T/. .AE