Heavy Quark Physics

这项研究的中心焦点是b夸克和c夸克的弱衰变。弱电相互作用的标准模型已经非常成功地解释了当前的数据，但有许多理由认为该模型是不完整的，例如，该模型不能解释不同的夸克或轻子质量或夸克之间的不同耦合。由于希望将重力与其他力联系起来，存在着等级问题，这只能在非常高的基本尺度上发生，比弱相互作用尺度大许多倍。将两个大小如此不同的标度连接起来，就定义了等级问题。对b和c衰变现象的研究可能有助于理解这一层次，并可能揭示标准模型之外的新物理。最重要的测量之一是CP破坏，即物质和反物质之间的不对称。必须测量四个独立的CP破坏角。这需要大量的数据样本和精确的检测技术，以便从模型中寻找数据中的偏差。康奈尔电子存储环(CESR)的CLEO实验是电子与正电子的碰撞实验，一直处于b夸克和c夸克研究的前沿。CLEO发现了BO、B+和DS介子。最近，CESR降低了能量，用于进行魅力物理和psi光谱的精确研究。在较低的质心能量下，可以研究魅力介子的弱衰变，这种方法可以大大减少系统误差，并对解释衰变数据所需的理论计算提供关键的检验。锡拉丘兹小组提议为CLEO升级建造粒子识别设备，名为环成像切伦科夫探测器。小组成员还参与了CLEO电磁量热仪和CLEO II的Muon探测器。费米实验室的Tevatron使质子与反质子碰撞。这些碰撞产生了非常高的b夸克和c夸克，其速率大约是CESR或其他e+e对撞机产生的1,000-10,000倍。BTeV实验将使用Tevatron来扩展物理覆盖范围，远远超出e+e对撞机所能完成的范围。BTeV希望在稀有衰变和CP破坏领域发现重要的新现象。这项提议通过继续在K-12、本科和研究生教育方面的努力，通过教育推广，提供更广泛的影响。小组成员一直活跃在小学科学俱乐部，并一直与高中老师互动。该组织有一个网站，专门回答有关粒子物理和一般科学的问题，名为“向粒子物理学家提问”。

The central focus of this research is the weak decay of the b quarks and the c quarks. The Standard Model of electroweak interactions has been very successful explaining current data, but there are many reasons to believe that the model is incomplete, e.g., the model cannot explain the different quark or lepton masses or the different couplings between the quarks. There is a hierarchy problem that arises from the desire to connect gravity with the other forces, which can occur only at a very high fundamental scale, many times larger than weak interaction scale. Connecting the two scales so different in magnitude defines the hierarchy problem. Study of phenomena in b and c decays may help to understand this hierarchy and could reveal new physics beyond the Standard Model. One of the most important measurements concerns CP violation or the asymmetry between matter and anti-matter. There are four independent CP violating angles that must be measured. These require large data samples and precise detection techniques in order to look for deviations in the data from the model. The CLEO experiment at the Cornell Electron Storage Ring (CESR), which collides electrons with positrons, has been at the forefront of studies of both the b and c quarks. The Bo, B+ and Ds mesons, were discovered by CLEO. Recently, CESR has lowered its energy to perform precision studies of charm physics and psi spectroscopy. At the lower center-of-mass energy, weak decays of charm mesons can be studied in way that drastically reduces systematic errors and provides a crucial check on theoretical calculations necessary to interpret b decay data. The Syracuse group proposes to build the particle identification device, called a Ring Imaging Cherenkov detector for the CLEO upgrade. Group members were also involved with the CLEO Electromagnetic Calorimeter and the Muon detector for CLEO II. The Fermilab Tevatron collides protons with anti-protons. These collisions produce very high rates of b and c quarks at rates about 1,000 - 10,000 times those produced at CESR or other e+e colliders. The BTeV experiment will use the Tevatron to extend the physics reach well beyond what can be done at e+e colliders. BTeV expects to find important new phenomena in the areas of rare decays and CP violation. This proposal provides broader impact through education outreach by continuing efforts in K-12, undergraduate and graduate education. Group members have been active in elementary school science clubs and have been interacting with High School teachers. The group has a website devoted to answering questions about particle physics and science in general, called "Ask a Particle Physicist."