The Relativistic Heavy Ion Collider (RHIC) at BNL provides a unique opportunity to collide polarized protons. One of the hightlight of the spin program at s~(1/2) = 500 GeV is the direct measurement of sea quark contribution to the proton spin via W-boson production by measuring parity violating single spin asymmetry. A new trigger on forward muons in PHENIX identifies and triggers on high momentum Ws suppressing a large number of low momentum muons coming from hadronic decays. Since the current muon trigger will fire on any muon above 2 GeV/c, it will not provide the required rejection factor for 500 GeV running, which is about 7500. Two major upgrade projects are parts of this Muon Trigger; 1) Resistive Plate Chambers, 2) the muon tracker front end electronics upgrades. The status of these upgrade projects is discussed in this document as well as physics goal of W program at RHIC.
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