Shedding light into the nature of the B anomalies

• Applicant: Dr. Maria Laura Piscopo
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 500314741

In light of the observed anomalies in the b-sector, with the present project I aim to perform a study of the B_s system. Specifically, I plan to consider the exclusive semileptonic decay B_s \to \phi \ell \ell and the mixing of neutral B_s-mesons, in order to improve the theoretical prediction for the corresponding experimentally relevant observables and constrain the size of possible CP violating new physics effects. In fact, despite the numerous analyses already available in the literature of the exclusive semileptonic B_s \to \phi \ell \ell decay, a complete study of the hadronic effects, responsible for the main theoretical uncertainty, in the framework of light-cone sum rules and using the \phi-meson distribution amplitudes, is still missing. This project has been designed to fill this gap, given that by using only the \phi-meson distribution amplitudes in the computation of the hadronic effects, the uncertainties due to correlation will be reduced, allowing a more precise theoretical prediction. With improved SM calculations, and in light of the tension with the experimental determination of the branching fraction and of the angular observables for the B_s \to \phi \ell \ell decay, I plan to perform a study of the available CP-violating parameter space for specific BSM models, and in particular analyse the impact of the new physics Wilson coefficients on B_s-mixing observables, like the mass-difference, and the semileptonic CP-asymmetries.

• DFG Programme: WBP Position