ABSTRACT
In the last few years there has been great experimental progress in quark flavour physics. The validity of the Standard Model (SM) has been strongly reinforced by a series of challenging experimental tests in B, D and K decays. All the relevant SM parameters controlling quark-flavour dynamics (the quark masses and the angles of the Cabibbo-Kobayashi-Maskawa matrix [1,2]) have been determined with good accuracy. More importantly, several suppressed observables (such as ΔmBd , ΔmBs , ACPKΨ, B → Xsγ, K , . . . ) that are potentially sensitive to physics beyond the SM have been measured with good accuracy and show no deviations from the SM. The situation is somewhat similar to the flavour-conserving electroweak precision observables after LEP: the SM works very well and genuine one-loop electroweak effects have been tested with relative accuracy in the 10%–30% range. As in the case of electroweak observables, non-standard effects in the quark flavour sector can only appear as small corrections to the leading SM contribution.
