Long-lived particle research at CERN
The Compact Muon Solenoid (CMS) is one of the larger particle physics detectors at CERN, with almost 4 000 researchers working there. One of the working groups at the CMS searched for exotic long-lived particles, which have never been detected. Funded by the EU, the project 'Search for new long-lived elementary particles decaying to tau leptons in the CMS experiment' (LONG-LIVED PARTICLES) searched for tau leptons, which would indicate the presence of such long-lived particles. The project studied proton–proton collisions at 7–8 teraelectronvolt and looked for displaced charged particle tracks and displaced jets. Unfortunately, no long-lived particles were detected during the project. Other activities included convening the long-lived search group as well as the exotic particle group at the CMS. Several academic papers were published through these groups. Finally, LONG-LIVED PARTICLES collaborated with research groups in the United Kingdom to develop a research and development strategy going forward. This has ensured a role for United Kingdom physics groups in hardware development for the CMS in the future.