Sea quark polarization results from STAR

Polarized proton-proton collision experiments at RHIC provide unique opportunities to study the spin structure of nucleon. One of the primary motivations of RHIC spin program is to probe sea quark spin-flavor structure via the $W$ boson production at $\sqrt{s}=$ 500 GeV proton-proton collisions. The $W$ longitudinal single-spin asymmetry, $A_L$, measurements with STAR have provided significant constraints on the polarized Parton Distribution Functions and especially the first experimental indication of a flavor asymmetry of polarized sea. In this talk, the final $W$ $A_L$ results from STAR and their impacts on the sea quark polarization will be presented.