CJ global QCD analysis with RHIC weak boson data

We present the recent update from the CTEQ-Jefferson Lab (CJ) global QCD analysis with W and Z data from the STAR experiment at RHIC. Weak boson productions in proton collisions provide unique opportunies to access light quarks in the proton. The cross sections and their ratio are sensitive to the light quark distributions near the valence region at RHIC energy, and in particular can help to constraint db/ub at large-x region.