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Search for third-generation scalar leptoquarks in the t-tau channel in proton-proton collisions at sqrt(s) = 8 TeV

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CMS [UCL] Basegmez, Suzan [UCL] Beluffi, Camille [UCL] Bondu, Olivier [UCL] Bruno, Giacomo [UCL] Castello, Roberto [UCL] Caudron, Adrien [UCL] Ceard, Ludivine [UCL] Da Silveira, Gustavo Gil [UCL] Delaere, Christophe [UCL] Du Pree, Tristan [UCL] Favart, Denis [UCL] Forthomme, Laurent [UCL] Giammanco, Andrea [UCL] Hollar, Jonathan [UCL] Jafari, Abideh [UCL] Jez, Pavel [UCL] Komm, Matthias [UCL] Lemaitre, Vincent [UCL] Mertens, Alexandre [UCL] Nuttens, Claude [UCL] Perrini, Lucia [UCL] Pin, Arnaud [UCL] Piotrzkowski, Krzysztof [UCL] Popov, Andrey [UCL] Quertenmont, Loic [UCL] Selvaggi, Michele [UCL] Vidal Maroño, Miguel [UCL]

A search for pair production of third-generation scalar leptoquarks decaying to top quark and tau lepton pairs is presented using proton-proton collision data at a center-of-mass energy of sqrt(s) = 8 TeV collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 19.7 inverse femtobarns. The search is performed using events that contain an electron or a muon, a hadronically decaying tau lepton, and two or more jets. The observations are found to be consistent with the standard model predictions. Assuming that all leptoquarks decay to a top quark and a tau lepton, the existence of pair produced, charge -1/3, third-generation leptoquarks up to a mass of 685 GeV is excluded at 95% confidence level. This result constitutes the first direct limit for leptoquarks decaying into a top quark and a tau lepton, and may also be applied directly to the pair production of bottom squarks decaying predominantly via the R-parity violating coupling lambda'[333].

Document type Article de périodique (Journal article) – Article de recherche
Access type Accès libre
Publication date 2015
Language Anglais
Journal information "Journal of High Energy Physics" - Vol. 1507, p. 042 (2015)
Peer reviewed yes
e-issn 1029-8479
Publication status Publié
Affiliation UCL - SST/IRMP - Institut de recherche en mathématique et physique
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Bibliographic reference CMS ; Basegmez, Suzan ; Beluffi, Camille ; Bondu, Olivier ; Bruno, Giacomo ; et. al. Search for third-generation scalar leptoquarks in the t-tau channel in proton-proton collisions at sqrt(s) = 8 TeV. In: Journal of High Energy Physics, Vol. 1507, p. 042 (2015)
Permanent URL http://hdl.handle.net/2078.1/184713