Study of Rare Muon Decay: with Polarized Muons

We studied the rare muon decay process . This Standard Model process is the background with respect to the signal process which is predicted by many extensions of the SM. We show that the process could be suppressed by cuts on the total energy of charged leptons in the kinematic region where the signal of new physics such as is expected to appear. Also, we demonstrated that angular distributions of decay products in the process are sensitive to the muon polarization and could be used to distinguish the signal of new physics from the background process .