Heavy Quark Physics

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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."