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

极化pp碰撞中的W产生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夸克-反夸克散射。事实上，W+应该由左手上夸克和右手反下夸克产生。因此，在pp碰撞中产生W是研究质子自旋味道结构的最好工具之一。在布鲁克海文国家实验室的相对论重离子收集器(RHIC)上，可以将自旋极化的质子束加速到250GeV，并将它们碰撞产生丰富的W玻色子。W的产生可以通过探测到高动量的Muon来确定。为了在PHENIX实验上实现这样的测量，我们应该提供一个额外的能力来触发数据采集系统，通过选择高动量Muon候选者来实现。在本研究项目中，我们开发了电子板，将提供的命中信息从Muon跟踪探测器转化为触发判决算法。新开发的电子板从Muon跟踪探测器窃取大约10%的脉冲，并放大到给定的阈值进行识别。这种命中信息将在现场可编程门阵列中处理，以选择高动量磁道，即在线水平的几乎直线磁道。新电子设备的加入肯定会增加现有读出系统的噪音水平，我们需要将这种影响降至最低。在这个研究项目中，我们已经开发出了性能最优的电子板，并用实际的Muon跟踪探测器证明了噪声水平的提高是完全可以接受的。因此，我们现在已经准备好生产新的电子系统，实现动量选择性Muon触发。用于菲尼克斯实验。

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.