Subtle Tests of the Standard Model and Probes for New Physics

University Of Notre Dame, Notre Dame IN

Investigators

Abstract

It had been recognized from the beginning that the existence and the pattern of heavy flavors represent one of the central mysteries in Nature's Grand Design in general and in the Standard Model (SM) in particular. Very considerable experimental as well as theoretical attention has therefore been focused on their study. These efforts have been intensified by the experiments at two B factories, a tau-charm factory, at hadronic colliders and a comprehensive program to study neutrino oscillations. They led to the first observation of CP violation outside neutral kaons decays and clear evidence for neutrino oscillations. The next step which is the core of this proposal is to have a precise analysis methodology that will allow one to extract of the numerical values of the fundamental parameters that drive CP violation in various systems, rare decays and neutrino oscillations, namely quark masses, quark and lepton mixing parameters. The theoretical framework for this analysis is the Heavy Quark Expansion, where transition rates are described by an expansion in inverse powers of the heavy quark mass. This is now at the stage of development where it is possible to attempt to determine SM quark parameters from data with a theoretical uncertainty not exceeding the very few percent level. To achieve such a goal one has to subject a judiciously chosen host of data to a careful quantitative theoretical analysis with a high degree of internal redundancy. One actually hopes to find inconsistencies with the predictions from the SM, which would constitute manifestations of New Physics beyond the SM.