Nonperturbative Strong Interaction Effects in High Energy Processes Mark Wise, Caltech

At high energies many physical quantities that are sensitive to the strong interactions can be calculated to high accuracy using perturbation theory in the strong coupling constant. But these quantities are not totally insensitive to strong interaction effects that cannot be described using perturbation theory. Furthermore it is important to quantify the size of these nonperturbative effects in order to accurately extract some of the constants of nature (e.g., the strong coupling constant, weak mixing angles and quark masses) from data. I describe how one estimates the size of these nonperturbative effects in three examples: the Z boson decay width, the electron energy spectrum in the decays of B-mesons and the shape of events where the Z boson decays to strongly interacting particles. These three examples have very different sensitivity to non perturbative strong interaction effects.