The Nucleon's Antiquark Sea: A Virtual Meson Cloud or Gluons?

We study the possible contribution of the nucleon's virtual meson cloud to the sea quark distribution as observed in deep inelastic lepton scattering. We adjust the meson-nucleon cut-offs to the large-x tails of the antiquark distributions, find qualitatively different behavior in the flavor singlet and non-singlet channels and study the scale dependence of our results. We demonstrate that, within convolution models, to reproduce the sea quark distribution the relevant pion momenta should be around 0.8 GeV.