MRI: Development of a Silicon Vertex Detector for the Higgs Search at the Tevatron Collider

该提案要求支持开发硅顶点探测器，以便使用费米实验室Tevatron质子-反质子对撞机II运行中的D0探测器发现长期寻找的希格斯玻色子。Tevatron对撞机是目前世界上唯一能够发现希格斯玻色子的设备。模拟研究表明，两个Tevatron对撞机实验，CDF和D0，对希格斯粒子几乎在目前允许的所有质量范围内都很敏感。此外，从欧洲核子研究中心最近退役的LEP正电子对撞机中，有一些证据表明，在费米实验室实验灵敏度最高的区域存在轻希格斯粒子（~115 GeV）。寻找希格斯玻色子的一个关键因素是能够从希格斯玻色子衰变中探测到b夸克。b夸克的寿命足够长（~1.5皮秒），可以通过硅顶点探测器精确测量带电粒子轨迹来识别。目前的D0硅探测器是在人们意识到发现希格斯粒子的潜力之前设计的，对希格斯粒子的研究来说，它的辐射难度还不够大。因此，D0合作已经着手设计一种新的硅顶点探测器，专门为希格斯粒子的搜索进行优化，将于2004年安装，届时目前的顶点探测器的性能将因辐射损伤而降低。有了这个MRI提案，一个由8个大学小组组成的联盟，其中5个目前由美国国家科学基金会（NSF）支持他们的D0工作，提议为将要建造的6层中的5层开发、采购、组装和测试硅传感器组件。这些组件是进行带电轨道测量的有源元件，是探测器的主要组成部分。这种新型硅顶点探测器的开发将是大学小组和费米实验室的联合开发项目。这项工作的大部分智力和技术领导来自大学团体。美国国家科学基金会的支持将为该项目带来强大的智力和技术投入，通过大学教师和学生在各自机构密切合作，设计、制造和测试探测器组件。

This proposal requests support for the development of a Silicon Vertex Detector to allow discovery of the long-sought Higgs boson using the D0 detector in Run II at the Fermilab Tevatron proton-antiproton collider. The Tevatron collider is currently the only facility in the world capable of making a Higgs discovery. Simulation studies have shown that the two Tevatron collider experiments, CDF and D0, are sensitive to the Higgs over almost all its presently allowed mass range. Furthermore, there is some evidence from the recently decommissioned LEP electron-positron collider at CERN for a light Higgs (~115 GeV) in the region where the Fermilab experiments have their greatest sensitivity.A key element in the Higgs search is the ability to detect the b-quarks from Higgs decay. The b-quark lifetime is sufficiently long (~1.5 picoseconds) that it can be identified by a Silicon Vertex Detector that precisely measures charged particle tracks. The current D0 silicon detector was designed well before the potential for making a Higgs discovery was appreciated and is not sufficiently radiation-hard for the Higgs search. Thus, the D0 collaboration has embarked on designing a new Silicon Vertex Detector that is specifically optimized for the Higgs search, to be installed by 2004 when the performance of the current vertex detector will have been diminished by radiation damage.With this MRI proposal, a consortium of eight university groups, five of which are currently supported by the NSF for their D0 work, propose to develop, procure, assemble, and test the silicon sensor assemblies for five of the six layers that will be built. These assemblies are the active elements that make the charged track measurements and constitute a major contribution to the detector. The development of this new silicon vertex detector would be a joint development project between university groups and Fermilab. Much of the intellectual and technical leadership for this effort originates in the university groups. NSF support will bring strong intellectual and technical input to the project through the design, fabrication, and testing of detector components by university faculty and students working closely together at their home institutions.