Research in Elementary Particle Physics

芝加哥大学由美国国家科学基金会支持的实验基本粒子物理学（EPP）小组由几个研究小组组成，他们参与了下面讨论的四个实验：“千兆电子伏特加速器中的介子”（KTEV）实验目前正在费米实验室进行。它的目的是研究CP破坏和长寿命k介子的罕见衰变。CP违逆被认为是宇宙中物质和反物质对称性的起源。KTEV是一个对我们理解宇宙起源和演化至关重要的实验。在“费米实验室对撞机探测器”（CDF）实验中，重点是研究1.8 TeV（当今世界上可用的最高能量）的质子-反质子碰撞中的高动量转移事件。芝加哥小组负责构建第一级热量计触发器和硅跟踪处理器的电子系统。CDF实验正在升级，以便能够利用正在建设中的新主注入环提供的更高亮度。CDF实验是顶夸克的共同发现者之一。欧洲核子研究中心（CERN）大型正电子对撞机（LEP）的“多功能LEP设备”（OPAL）合作项目完成了一个项目，该项目使用Z玻色子衰变对粒子物理学的“标准模型”进行了几项重要测试：温伯格角的测量，各种b介子衰变的研究，以及寻找可能表明超出“标准模型”的物理的外来粒子。该项目目前正在“LEP200”上收集数据，在那里，加速器的能量是目前的两倍，可以产生W个介子对，从而获得W质量的直接测量。对新粒子的搜索也在这些更高的能量下进行。ATLAS（环面大角度光谱仪）将是一个通用探测器，旨在开发未来LHC质子-质子对撞机的潜力。LHC将提供比以前的对撞机高10倍的质心能量和100倍的质子-质子碰撞率，从而开辟了物理学的新前沿。发现质量产生机制或自发对称破缺，从而预测标量粒子希格斯玻色子的存在，是ATLAS的主要目标。芝加哥小组是EPP项目教育和推广活动的领导小组。

The NSF-supported experimental Elementary Particle Physics (EPP) group at the University of Chicago consists of several research teams which involve themselves in the four experiments discussed below: The `Kaon at the Tevatron` (KTEV) experiment is now running at Fermilab. Its intent is to study CP violation and the rare decays of long-lived K-mesons. CP violation is thought to be the origin of the a symmetry between matter and antimatter in the universe. KTEV is an experiment of fundamental importance to our understanding of the origins and evolution of the universe. At the `Collider Detector at Fermilab` (CDF) experiment, the focus is to study high momentum transfer events in proton-antiproton collisions at 1.8 TeV (the highest energy available in the world today). The Chicago group has the responsibility of constructing the electronic systems for the first level calorimeter trigger and the silicon tracker processor. The CDF experiment is being upgraded so that it can exploit the higher luminosity to be provided by the new main injector ring now under construction. The CDF experiment was one of the co- discoverers of the top quark. The `Omni-Purpose-Apparatus-at-LEP` (OPAL) collaboration at the Large Electron-Positron collider (LEP) at CERN has completed a program that uses Z boson decays to conduct several important tests of the `Standard Model` of particle physics: a measurement of the Weinberg angle, a study of various B-meson decays, and a search for exotic particles that would indicate physics beyond the `Standard Model`. The collaboration is now taking data at `LEP200`, where with double its present energy, the accelerator can make W meson pairs and hence obtain direct measurements of the W mass. Searches for new particles are also being conducted at these higher energies. ATLAS (A Toroidal Large Angle Spectrometer) will be a general-purpose detector designed to exploit the potential of the future LHC proton-proton collider. LHC will provide 10 times higher center-of-mass energy and 100 times higher proton-proton collision rates than previous colliders, thus opening up a new frontier of physics. Discovery of the mass- generating mechanism or spontaneous symmetry breaking, which predicts the existence of a scalar particle, the Higgs boson is a primary objective of ATLAS. The Chicago group is the leading group in the EPP program in its education and outreach activities.