Reconstruction and Identification of Hadronic Decays of Taus using the CMS Detector

Because the tau is the heaviest of the three leptons, specific final states involving taus are expected to show up in the Standard Model (SM), and would appear abundantly in many processes arising from new physics beyond the SM. Because taus decay to hadronic final states in about 64% of the cases, the reconstruction and identification of these hadronic decays is an essential ingredient of the Compact Muon Solenoid (CMS) physics programme. The CMS tau identification uses objects from the particle-flow reconstruction, which combines information from all CMS subdetectors to produce a global event description at the level of individually reconstructed particles. The individual particle list includes muons, electrons (with individual bremsstrahlung photons), photons (unconverted or converted), charged hadrons (without or with a nuclear interaction in the tracker), and stable and unstable neutral hadrons. The details of the particle-flow algorithm and its full implementation in CMS will be described in a forthcoming paper [3].