Contribution of Form Factors to the Pion Cloud of the Proton

We have investigated the contribution of the pion cloud to the excess of $\bar{d}$ over $\bar{u}$ in the proton sea. In the pion cloud model, the number of pions produced depends on the splitting function $f_\pi (y)$, the cutoff form factor $F_{\pi N} (t)$, and the parton distribution functions of the pion. We have studied how these factors affect the pion cloud and, therefore, the excess of $\bar{d}$ over $\bar{u}$. We examine the effects of $Q^2$ evolution. We compare our theoretical results to the HepData parton distributions provided by Durham University and to the experimental E866 data from Fermilab.