Quark flavour mixing with right-handed currents: An effective theory approach Original Research Article

The impact of right-handed currents in both charged- and neutral-current flavour-violating processes is analysed by means of an effective theory approach. More explicitly, we analyse the structure of dimension-six operators assuming a left–right symmetric flavour group, commuting with an underlying image global symmetry, broken only by two Yukawa couplings. The model contains a new unitary matrix controlling flavour-mixing in the right-handed sector. We determine the structure of this matrix by charged-current data, where the tension between inclusive and exclusive determinations of image can be solved. Having determined the size and the flavour structure of right-handed currents, we investigate how they would manifest themselves in neutral current processes, including particle–antiparticle mixing, image, image, image, and image decays. The possibility to explain a non-standard CP-violating phase in image mixing in this context, and the comparison with other predictive new-physics frameworks addressing the same problem, is also discussed. While a large image asymmetry can easily be accommodated, we point out a tension in this framework between image and image.