Effective Theories for Quark Flavour Physics

The purpose of these lectures is to provide the reader with an idea of how we can probe New Physics with quark flavour observables using effective theory techniques. After giving a concise review of the quark flavour structure of the Standard Model, we introduce the effective Hamiltonian for quark weak decays. We then consider the effective Hamiltonian for $\mathrm{\Delta }F=2$ transitions in the Standard Model and beyond. We discuss how meson-antimeson mixing and CP violation can be described in terms of the $\mathrm{\Delta }F=1$ and $\mathrm{\Delta }F=2$ effective Hamiltonians. Finally we present the Unitarity Triangle Analysis and discuss how very stringent constraints on New Physics can be obtained from $\mathrm{\Delta }F=2$ processes.