Heavy Quark Physics at Babar

请拨资金支持辛辛那提大学两名教授的研究。研究工作集中在斯坦福直线加速器中心(SLAC)，并利用巴布尔探测器设施。巴布尔探测器是由包括和平研究所在内的大型国际合作建造的，在过去五年中一直在不断使用。巴布尔实验的主要科学目标是研究CP破坏，这是宇宙粒子-反粒子不对称的重要组成部分，以及它与描述基本粒子之间相互作用的标准模型(SM)的关系。特别是，SM预言，B介子各种衰变的测量可以通过3x3 Cabbibo-Kobayaski-Maskawa(CKM)矩阵联系起来。该矩阵中的相位通过一个单位三角形联系在一起，该三角形的三个角度α、β和伽马的角度之和应为180度。巴布尔实验在SLAC使用PEP2加速器，该加速器旨在提供大量的B介子。高的B介子通量使研究许多适合测量每个混合角的稀有衰变模式成为可能。该实验还产生了其他有趣的物理结果，包括令人惊讶地发现了具有不寻常性质的新的奇怪、迷人的介子(DSJ)。PI们直接参与了这一发现。辛辛那提小组建议进行分析，以测量角度，伽马，以及在研究B和D介子和其他重夸克系统中重要的其他研究。这些研究将包括寻找中性D系统中的混合等现象，这些现象可能涉及SM以外的物理问题。巴布尔实验在所谓的工厂模式下运行，这是生产大量B介子所需的条件。这种运行模式要求每个大学小组的所有成员都致力于重要的服务任务。辛辛那提小组主要致力于DIRC-一种新型颗粒识别设备的研究。BABA和PEP2都运行良好。PEP2的运行水平大大超过了它的设计规范。在其更广泛的影响中，这项提议将有助于辛辛那提小组的学生和博士后助理的教育。他们除了在受到密切关注的基本粒子物理环境中接受培训外，还接触到了大量最新的技术。在SLAC的基础上，他们的努力受到了那里发现的一大批重要物理学家的关注。他们在各种环境中的计算、电子和机械系统的诊断以及在大型协作所需的几乎每天的会议上展示结果和想法方面变得非常熟练。

Funds are requested to support the research of two professors at the University of Cincinnati. The research effort is concentrated at the Stanford Linear Accelerator Center (SLAC) and makes use of the BaBar detector facility. The BaBar detector was built by a large international collaboration including the PIs and has been in continuous use for the past five years. The principal scientific goal of the BaBar experiment is the study of CP violation, an important ingredient in the particle-antiparticle asymmetry of the universe, and its relationship with the Standard Model (SM) describing interactions between elementary particles. In particular, the SM predicts that measurement of various decays of B mesons can be related through the 3x3 Cabbibo-Kobayaski-Maskawa (CKM) matrix. The phases in this matrix are related through a unitarity triangle whose three angles, alpha, beta, and gamma, should sum to 180 degrees. The BaBar experiment uses the PEP2 accelerator at SLAC, which was designed to provide a large number of B mesons. The high B meson flux makes it possible to examine many rare decay modes that are suitable for measurement of each of the mixing angles. The experiment has also produced other interesting physics results, including the surprising discovery of new strange, charmed mesons (DsJ ) with unusual properties. The PIs were directly involved in this discovery. The Cincinnati group proposes to carry out analyses aimed at measurement of the angle, gamma, and at other investigations of importance in the study of B and D mesons and other heavy quark systems. These studies will include a search for phenomena such as mixing in the neutral D system that may involve physics beyond the SM. The BaBar experiment runs in a so-called factory mode, which is a requirement for producing the large number of B mesons needed. This mode of running mandates that all members of each university group work on significant service tasks. The Cincinnati group works largely on the DIRC - a novel particle identification device. Both BaBar and PEP2 are working well. PEP2 is running at levels that significantly exceed its design specifications.In its broader impacts, this proposal will contribute to the education of the students and postdoctoral associates in the Cincinnati group. They are exposed to a great deal of up-to-date technology, in addition to being trained in a closely watched environment in elementary particle physics. Based at SLAC, their efforts are on view to a large community of important physicists who are found there. They become highly skilled in computing in various environments, in the diagnosis of electronic and mechanical systems, and in presentation of results and ideas in the almost daily meetings required of a large collaboration.