Chiral perturbation theory for and

Abstract

Abstract The decay constants for D and Ds mesons, denoted fD and fDS respectively, are equal in the SU(3)V limit, as are the hadronic amplitudes for B S − B S and B 0 − B 0 mixing. The leading SU(3)V violating contribution to (FDS/FD) and to the ration of hadronic matrix elements relevant for B S − B S and B 0 − B 0 mixing amplitudes are calculated in chiral perturbatiion theory. We discuss the formalism needed to include both meson and anti-meson fields in the heavy quark effective theory.