Determination of the sea-quark distributions in the proton by single-particle inclusive reactions

We have determined the sea-quark distributions of the proton by using recent data on meson production in the proton fragmentation region in high-energy proton-proton collisions. We find that the magnitude of the sea distributions in hadron reactions is larger than the sea measured in lepton experiments. We interpret this enhancement as due to the additional contribution of quark-antiquark pairs created in the initial hadron collision. From our determination of the sea-quark distributions we are able to predict a number of particle ratios in single-particle inclusive production in $p-p$ collisions. In addition, we have calculated the production cross section for low-mass muon pairs by the Drell-Yan mechanism and have obtained good agreement with experiment.