Prospects of CMS in B physics in Phase 2

The Standard Model of Particle Physics precisely predicts the cross-sections for the processes $B_s \rightarrow \mu\mu$ and $B_d \rightarrow \mu\mu$ which are suppressed in the SM. Beyond SM (BSM) contribution can enhance the decay rates. Precise measurement of branching fractions and of the $B_s \rightarrow \mu\mu$ decay effective lifetime is of prime concern for experiments like CMS in the quest for new physics. The SM also precisely predicts the CP violating phase $\phi_s$ in the $B_s \rightarrow \phi\phi \rightarrow$ 4 Kaons decay, a significant deviation from the SM prediction would provide a clear signature for BSM. During the High Luminosity (HL) period of the LHC, also known as LHC Phase-2, which will start from 2026, CMS will try to look for these processes. The $B_{d/s} \rightarrow \mu\mu$ is an extremely rare FCNC process with a fully leptonic final state whereas $B_s \rightarrow \phi\phi \rightarrow$ 4 Kaons too is a rare process with a fully hadronic final state. The inclusion of the tracking information in the Level1 Trigger during Phase-2 will help a general purpose detector like CMS to look for such fully hadronic final states for the first time. In this talk, we shall discuss about the CMS Phase-2 Tracker, Level1 tracking and present results obtained from Phase-2 simulation for $B_{d/s} \rightarrow \mu\mu$ and $B_s \rightarrow \phi\phi \rightarrow$ 4 Kaons.