Effect of sea quarks on the single-spin asymmetries $A_L^{W^{\pm }}$ in polarized pp collisions at RHIC

We calculate the single-spin asymmetries $A_L^{W^{\pm }}$ of $W^{\pm }$ bosons produced in polarized pp collisions with the valence part of the up and down quark helicity distributions modeled by the light-cone quark-spectator-diquark model while the sea part helicity distributions of the up and down quarks treated as parametrization. Comparing our results with those from experimental data at RHIC, we find that the helicity distributions of sea quarks play an important role in the determination of the shapes of $A_L^{W^{\pm }}$. It is shown that $A_L^{W^{-}}$ is sensitive to $\Delta \bar u$,while$A^{W^{+}}_{L}$to$\Delta \bar d$ intuitively. The experimental data of the polarized structure functions and the sum of helicities are also important to constrain the sizes of quark helicity distributions both for the sea part and the valence part of the nucleon.