Study of the Spin Structure of the Nucleon with W production in polarized pp collisions

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W production in polarized pp collisions is expected to play an important role in investigation of anti-quark distribution in the proton, since its production is dominated by quark-anti-quark scattering. Indeed, W+ should be produced from left handed up quark and right handed anti-down quark. Therefore W production in pp collision is one the best tools to study the spin flavor structure of the proton.At the Relativistic Heavy Ion Colliser (RHIC) at Brookhaven National Laboratory can accelerate spin polarized proton beams up to 250 GeV and collide them to produce W boson copiously. Production of W can be identified with the detection of high momentum muon. To realize such measurement at PHENIX experiment, we should provide an additional capability to trigger data acquisition system by selecting the high momentum muon candidates. In this research program, we have developed the electronics board to provide a hit information from Muon Tracking Detector into the trigger decision algorithm. The newly developed electronics board steals about 10% of the pulse from the Muon Tracking Detector and amplifies to be discriminated with a given threshold. Such hit information will be processed in the Field Programmable Gate Arrays to select high momentum tracks, i.e. almost straight tracks at online level. This addition of the new electronics certainly increase the noise level in the existing read out system, and we need to minimize such effects. Within this research program, we have developed the electronics board with an optimal performance, and demonstrated that the increase in the noise level is fully acceptable with the real Muon Tracking Detectors.Consequently we are now ready for the production of the new electronics system to realize the momentum selective muon trigger. For PHENIX experiment.