Search for the lepton flavor violating decay $\tau$ $\to$ 3$\mu$ in proton-proton collisions at $\sqrt{s} =$ 13 TeV

• Published in: The journal of high energy physics Vol. 1
• Main Authors: Sirunyan, Albert M, Tumasyan, Armen, Adam, Wolfgang, Ambrogi, Federico, Bergauer, Thomas, Dragicevic, Marko, Erö, Janos, Escalante del Valle, Alberto, Fruehwirth, Rudolf, Jeitler, Manfred, Krammer, Natascha, Lechner, Lukas, Liko, Dietrich, Madlener, Thomas, Mikulec, Ivan, Pitters, Florian Michael, Rad, Navid, Schieck, Jochen, Schöfbeck, Robert, Spanring, Markus, Templ, Sebastian, Waltenberger, Wolfgang, Wulz, Claudia-Elisabeth, Zarucki, Mateusz, Chekhovsky, Vladimir, Litomin, Aliaksandr, Makarenko, Vladimir, Suarez Gonzalez, Juan, Darwish, Mohamed Rashad, de Wolf, Eddi A, Di Croce, Davide, Janssen, Xavier, Kello, Tomas, Lelek, Aleksandra, Pieters, Maxim, Rejeb Sfar, Haifa, van Haevermaet, Hans, van Mechelen, Pierre, van Putte, Senne, van Remortel, Nick, Blekman, Freya, Bols, Emil Sørensen, Chhibra, Simranjit Singh, d'Hondt, Jorgen, de Clercq, Jarne, Lontkovskyi, Denys, Lowette, Steven, Marchesini, Ivan, Moortgat, Seth, Morton, Alexander, Python, Quentin, Tavernier, Stefaan, van Doninck, Walter, van Mulders, Petra, Beghin, Diego, Bilin, Bugra, Clerbaux, Barbara, de Lentdecker, Gilles, Delannoy, Hugo, Dorney, Brian, Favart, Laurent, Grebenyuk, Anastasia, Kalsi, Amandeep Kaur, Makarenko, Inna, Moureaux, Louis, Pétré, Laurent, Popov, Andrey, Postiau, Nicolas, Starling, Elizabeth, Thomas, Laurent, Vander Velde, Catherine, Vanlaer, Pascal, Vannerom, David, Wezenbeek, Liam, Cornelis, Tom, Dobur, Didar, Gruchala, Marek, Khvastunov, Illia, Niedziela, Marek, Roskas, Christos, Skovpen, Kirill, Tytgat, Michael, Verbeke, Willem, Vermassen, Basile, Vit, Martina, Bruno, Giacomo, Bury, Florian Joel J, Caputo, Claudio, David, Pieter, Delaere, Christophe, Delcourt, Martin, Donertas, Izzeddin Suat, Giammanco, Andrea, Lemaitre, Vincent, Mondal, Kuntal, Prisciandaro, Jessica, Taliercio, Angela, Teklishyn, Maksym, Vischia, Pietro, Wuyckens, Sophie
• Format: Journal Article
• Language: English
• Published: Springer 2021
• Subjects: High Energy Physics - Experiment; Physics; experimental results; S035.35; Hadron-Hadron scattering (experiments); CMS; CERN LHC Coll; heavy quark; Lepton production; lepton: flavor: violation; tau: branching ratio: upper limit; background; hadron: decay; p p: colliding beams; p p: scattering; Tau Physics; 13000 GeV-cms; tau > > 3muon
• ISSN: 1126-6708; 1029-8479
• DOI: 10.1007/JHEP01(2021)163

Results are reported from a search for the lepton flavor violating decay τ → 3μ in proton-proton collisions at $ \sqrt{\mathrm{s}} $ = 13 TeV. The data sample corresponds to an integrated luminosity of 33.2 fb$^{−1}$ recorded by the CMS experiment at the LHC in 2016. The search exploits τ leptons produced in both W boson and heavy-flavor hadron decays. No significant excess above the expected background is observed. An upper limit on the branching fraction ℬ(τ → 3μ) of 8.0 × 10$^{−8}$ at 90% confidence level is obtained, with an expected upper limit of 6.9 × 10$^{−8}$.[graphic not available: see fulltext]