Challenging the Standard Model of Particle Physics and the CMS trigger with flavour 

In the Standard Model of particle physics the three charged leptons - electron, muon and tau - have identical couplings when participating in electroweak interactions. This is the essence of a universal principle, known as lepton flavour universality, which has been confirmed by several measurements on a wide range of particle decays. Recently, several indications of possible deviations from this principle have been reported by different experiments puzzling the scientific community. New physics beyond the Standard Model can manifest itself via lepton-flavour-violating (LFUV) processes in collisions at the Large Hadron Collider (LHC). 

In this talk I will discuss the lepton-flavour-universality-violation physics program of the Compact Muon Solenoid (CMS) experiment at the LHC, focusing on the first LFUV measurement between taus and muons using Bc mesons. 

Following this first result, the CMS Collaboration is investing further resources with dedicated trigger strategies to expand its sensitivity in this research domain. I will present the current status and prospects for future discoveries.