Radiative, semileptonic and leptonic decays of B mesons

Radiative, semileptonic and leptonic decays of B-meson offer an invaluable opportunity to probe New Physics (NP) beyond the Standard Model (SM). 

In this proposal, the decay rate of a number of processes mediated by charged and neutral flavor changing currents will be computed. These will be compared with the experimental measurement to check the consistency of the flavor sector of the SM and to constrain NP scenarios. Calculations will entail the evaluation of two- and three-points correlation functions, in the framework of the Lattice regularization of Quantum Chromodynamics, relying on the simulation of physical mass light quarks on large volumes with fine lattice spacings. The large memory requirements necessitate massive parallelization on an HPC infrastructure, to be exploited thanks to a consolidated set of efficient numerical libraries.  

The project will rely on our recent experience gained in the study of charm and b-quark physics. A mixture of well tested and novel approaches will push the understanding of the weak interaction processes involving Bs/Ds and lighter mesons, in several directions: providing predictions on rare processes that will be measured in the near future such as the B+(c)→𝜇𝜈𝛾, B→ Kℓℓ and Bs→ϕγ or substantially improving the theoretical description of well established measurements such as B→D(*)ℓ𝜈.