https://doi.org/10.1140/epjc/s10052-018-6393-9
Regular Article - Theoretical Physics
Decoding (pseudo)-scalar operators in leptonic and semileptonic B decays
1
Nikhef, Science Park 105, 1098 XG, Amsterdam, The Netherlands
2
Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV, Amsterdam, The Netherlands
* e-mail: rjaarsma@nikhef.nl
Received:
2
October
2018
Accepted:
27
October
2018
Published online:
10
November
2018
We consider leptonic and semileptonic
,
decays and present a strategy to determine short-distance coefficients of New-Physics operators and the CKM element
. As the leptonic channels play a central role, we illustrate this method for (pseudo)-scalar operators which may lift the helicity suppression of the corresponding transition amplitudes arising in the Standard Model. Utilising a new result by the Belle collaboration for the branching ratio of
, we explore theoretically clean constraints and correlations between New Physics coefficients for leptonic final states with
and
leptons. In order to obtain stronger bounds and to extract
, we employ semileptonic
and
decays as an additional ingredient, involving hadronic form factors which are determined through QCD sum rule and lattice calculations. In addition to a detailed analysis of the constraints on the New Physics contributions following from current data, we make predictions for yet unmeasured decay observables, compare them with experimental constraints and discuss the impact of CP-violating phases of the New-Physics coefficients.
© The Author(s), 2018