Search for third-generation scalar leptoquarks decaying to a top quark and a $\tau$ lepton at $\sqrt{s}=$ 13 TeV

• Main Author: CMS collaboration (2291 authors)
• Publication Date: 2018
• Other Authors: Nayak, Aruna, Bargassa, Pedrame, Beirão Da Cruz E Silva, Cristóvão, Di Francesco, Agostino, Faccioli, Pietro, Galinhas, Bruno, Gallinaro, Michele, Hollar, Jonathan, Leonardo, Nuno, Lloret Iglesias, Lara, Seixas, Joao, Strong, Giles, Toldaiev, Oleksii, Vadruccio, Daniele, Varela, Joao, Vischia, Pietro, David Tinoco Mendes, Andre, Silva, Pedro, Musella, Pasquale
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: http://dx.doi.org/10.1140/epjc/s10052-018-6143-z; http://hdl.handle.net/10400.26/27590

A search for pair production of heavy scalar leptoquarks (LQs), each decaying into a top quark and a $\tau$ lepton, is presented. The search considers final states with an electron or a muon, one or two $\tau$ leptons that decayed to hadrons, and additional jets. The data were collected in 2016 in proton-proton collisions at $\sqrt{s}=$ 13 TeV with the CMS detector at the LHC, and correspond to an integrated luminosity of 35.9 fb$^{-1}$. No evidence for pair production of LQs is found. Assuming a branching fraction of unity for the decay LQ$ \to $t$\tau$, upper limits on the production cross section are set as a function of LQ mass, excluding masses below 900 GeV at 95% confidence level. These results provide the most stringent limits to date on the production of scalar LQs that decay to a top quark and a $\tau$ lepton.