Heavy Quark Physics

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This proposal requests support for the research program of the Syracuse University group which is focused on the weak decays of the b-quark and the c-quark. Although the Standard Model of electroweak interactions has been very successful in explaining most phenomena, the model cannot explain the different quark and lepton masses or the different couplings between the quarks. This group is looking for deviations in the data from the model, and in measuring several model parameters. The CLEO experiment at the Cornell Electron Storage Ring (CESR) electron-positron collider has been at the forefront of studies of both the b- and c-quarks. For example, the B0, B+, and DS mesons were all discovered at CLEO. The recent CLEO III upgrade has transformed the detector into a more powerful instrument by incorporating a new particle identification detector (RICH), new silicon-based vertex and tracking devices, and new fast electronics to accommodate increased luminosity from the CESR accelerator. The RICH detector was designed, built, and commissioned by this group. The proton-antiproton Tevatron collider at Fermilab produces copious numbers of b- and c-quarks at rates 1000-10000 larger than at CESR. However, the b-quark events must be extracted from hadronic backgrounds that are a factor of 1000 larger than the signal, whereas at CESR the backgrounds are only a factor of four larger than the signals. The BTeV experiment, designed to extend the physics reach of the electron-positron experiments, and whose co-spokesman is the PI of this group, has recently received stage one scientific approval from Fermilab management.