Search for Bs -> mu mu and B0 -> mu mu decays in CMS

Understand

A search for the rare decays (Bs -> \mu \mu) and (B0 -> \mu\mu) performed in pp collisions at sqrt{s} = 7 TeV is presented.

• The data sample, collected by the CMS experiment at the LHC, corresponds to an integrated luminosity of 1.14 /fb.
• In both cases the number of events observed after all selection requirements is consistent with expectations from background and standard model signal predictions.
• The resulting upper limits on the branching fractions are BF(Bs -> \mu\mu) < 1.9 * 10^{-8} and BF(B0 -> \mu \mu) < 4.6 * 10^{-9} at 95% confidence level (CL).