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

极化pp碰撞中W的产生预计将在质子反夸克分布的研究中发挥重要作用，因为它的产生主要是由夸克-反夸克散射决定的。事实上，W+应该是由左手上夸克和右手反下夸克产生的。因此，pp碰撞产生W是研究质子自旋风味结构的最佳工具之一。位于布鲁克海文国家实验室的相对论重离子对撞机（RHIC）可以将自旋极化质子束加速到250 GeV，并使其碰撞产生大量W玻色子。W的产生可以通过检测高动量μ子来确定。为了在PHENIX实验中实现这样的测量，我们应该通过选择高动量介子候选者来提供额外的触发数据采集系统的能力。在本研究计划中，我们开发了电子板，将μ子跟踪探测器的命中信息提供给触发决策算法。新开发的电子板从μ子跟踪探测器窃取约10%的脉冲，并放大以给定阈值进行区分。这些命中信息将在现场可编程门阵列中进行处理，以选择高动量轨道，即在线水平的几乎直线轨道。新增的新电子器件肯定会增加现有读出系统的噪声水平，我们需要将这种影响降到最低。在这个研究项目中，我们开发了具有最佳性能的电子板，并证明了噪声水平的增加与真正的μ子跟踪探测器完全可以接受。因此，我们现在已经准备好生产新的电子系统来实现动量选择性μ子触发。用于凤凰实验。

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.