Footprints of New Physics in the angular distribution of Bc→Ds⁎(→Dsγ,(Dsπ))ℓ+ℓ− decays

We investigate the angular decay distribution of the four-fold Bc→Ds⁎(→Dsγ)μ+μ−, and Bc→Ds⁎(→Dsπ)μ+μ− decays that proceed through b→sμ+μ− quark level transition. We use the model independent effective Hamiltonian with vector and axial vector new physics operators to formulate the angular observables and study the implications of different latest new physics scenarios, taken from the global fits to all the b→s data, on these observables. We also give Standard Model and new physics predictions of several observables such as differential branching ratios, forward backward asymmetry, longitudinal polarization fraction of Ds⁎, and the unpolarized and polarized lepton flavor universality violating ratios. Future measurements of the predicted angular observables, both at current and future high energy colliders, will add to the useful complementary data required to clarify the structure of new physics in b→sℓℓ neutral current decays

New physics in b → sℓℓ anomalies and its implications for the complementary neutral current decays

International audienceWe study the Standard Model and the new physics predictions for the lepton-flavour-universality violating (LFUV) ratios in various b→sℓ+ℓ− channels with scalar, pseudoscalar, vector, axial-vector, and Λ baryon final states, considering both unpolarized and polarized final state hadrons. In order to formulate physical observables, we use the model independent effective Hamiltonian approach and employ the helicity formalism. We provide the explicit expressions of the helicity amplitudes in terms of the Wilson coefficients and the hadronic form factors by using the same kinematical configuration and polarization conventions for all the decay channels. We perform the numerical analysis with new physics scenarios selected from the recent global fits to b→sℓ+ℓ− data, having specific new physics model interpretations. We find that some of the LFUV ratios for these complementary channels in different kinematical regions have high sensitivity to new physics and the future measurements of them in Belle II and LHCb experiments, along with testing new physics/LFUV, can help to distinguish among some of the different new physics possibilities