Würzburg 2018 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
T: Fachverband Teilchenphysik
T 88: Flavor Physik III
T 88.1: Vortrag
Donnerstag, 22. März 2018, 16:30–16:45, Z6 - SR 2.006
Test of lepton flavour universality using the branching fraction ratio Rφ — •Simon Nieswand, Sarah Beranek, Christoph Langenbruch, Stefan Schael, and Eluned Smith — I. Physikalisches Intitut, RWTH Aachen University
The LHCb detector at the LHC is designed for the search for New Physics (NP) beyond the Standard Model (SM) in decays of heavy flavour. Of particular interest are rare decays of b-hadrons that occur via b → s transitions. These flavour changing neutral currents are forbidden at tree-level in the SM. At loop-level they can be influenced by heavy non-SM particles. Therefore, the branching fractions of decays like Bs0 → φ ℓ+ℓ− constitute sensitive probes for NP.
Particularly clean theory predictions can be made for the ratios of rare semileptonic b → s decays with muons and electrons in the final state. Due to lepton universality, those ratios should be close to unity in the SM. For the ratios RK* and RK interesting tensions with the SM predictions were observed by the LHCb collaboration, corresponding to 2.4−2.5 and 2.6 σ, respectively. Therefore, it is interesting to study further rare B decays for a similar behavior.
In this talk the analysis strategy to measure the branching fraction ratio Rφ=B(Bs0 → φµ+µ−)/B(Bs0 → φ e+ e−) and the current status of the on-going analysis of the Run 2 LHCb data sample will be presented.