Thesis

Lepton Flavor Universality

• Call:

  PT-CERN Call 2021/2

• Academic Year:

  2021

• Domain:

  Astroparticle Physics

• Supervisor:

  Nuno Leonardo

• Co-Supervisor:

  Alessio Boletti

• Institution:

  Instituto Superior Técnico (Universidade de Lisboa)

• Host Institution:

  Laboratório de Instrumentação e Física Experimental de Partículas

• Abstract:

  Lepton flavor universality (LFU) is deeply ingrained in the symmetry structure of the standard model (SM). Indeed, the SM gauge group SU(3)xSU(2)xU(1) is one and the same for all three generations of fermions. However, recent data provide strong evidence for departures from the LFU principle. Such departures are reported in b quark decays to charged leptons of different flavors (electron, muon, tau). The definite observation of LFU violation, contrary to the SM, would have far reaching implications. It requires the presence of new particles beyond the SM (BSM), such as new gauge bosons (Z') or leptoquarks (LQ). The thesis project explores LFU observables in the most sensitive b->sll quark transitions using CMS data. The thesis project has the potential to deliver the first observation of New Physics at the LHC.