We present a high-statistics, species-identified measurement of the W-to-Be per-nucleon cross-section ratio, RW/Be, for high-xt hadrons and high- h+h- pairs produced in p-A collisions at s =38.8 GeV. The data extend to 0.62 in xt and 0.39 in . For single hadrons, RW/Be peaks at pt5 GeV/c and decreases to 1 for mesons with pt>8 GeV/c. At fixed pt, RW/Be falls with s. For symmetric pairs with >0.28, RW/Be=0.84±0.02±0.07, suggesting a nuclear suppression of high-z fragmentation. RW/Be increases with pout, indicative of constituent multiple scattering.
ASJC Scopus subject areas
- Physics and Astronomy(all)