Charming new physics in rare B-decays and mixing?

Understand

We conduct a systematic study of the impact of new physics in quark-level $b \to c \bar{c} s$ transitions on $B$-physics, in particular rare $B$-decays and $B$-meson lifetime observables.

• We find viable scenarios where a sizable effect in rare semileptonic $B$-decays can be generated, compatible with experimental indications and with a possible dependence on the dilepton invariant mass, while being consistent with constraints from radiative $B$-decay and the measured $B_s$ width difference.
• We show how, if the effect is generated at the weak scale or beyond, strong renormalisation-group effects can enhance the impact on semileptonic decays while leaving radiative $B$-decay largely unaffected.
• A good complementarity of the different $B$-physics observables implies that precise measurements of lifetime observables at LHCb may be able to confirm, refine, or rule out this scenario.