Search for pair production of third-generation scalar leptoquarks and top squarks in proton–proton collisions at √s = 8 TeV

A search for pair production of third-generation scalar leptoquarks and supersymmetric top quark partners, top squarks, in final states involving tau leptons and bottom quarks is presented. The search uses events from a data sample of proton–proton collisions corresponding to an integrated luminosit...

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Bibliographic Details
Main Authors: CMS Collaboration, Apyan, Aram, Barbieri, Richard Alexander, Busza, Wit, Cali, Ivan Amos, Chan, M., Di Matteo, Leonardo, Dutta, Valentina, Gomez-Ceballos, Guillelmo, Goncharov, Maxim, Gulhan, Doga Can, Klute, Markus, Lai, Yue Shi, Lee, Yen-Jie, Levin, Andrew Michael, Ma, Teng, Paus, Christoph M. E., Ralph, Duncan Kelley, Stephans, George S. F., Stoeckli, Fabian, Velicanu, Dragos Alexandru, Veverka, Jan, Wyslouch, Boleslaw, Yang, Mingming, Zanetti, Marco, Roland, Christof E, Roland, Gunther M, Sumorok, Konstanty C, Wyslouch, Victoria, Bauer, Gerry P, Luckey Jr, P David
Other Authors: Massachusetts Institute of Technology. Department of Physics
Format: Article
Language:en_US
Published: Elsevier B.V. 2015
Online Access:http://hdl.handle.net/1721.1/95797
https://orcid.org/0000-0002-3831-9071
https://orcid.org/0000-0003-3106-4894
https://orcid.org/0000-0001-6332-5839
https://orcid.org/0000-0001-8983-2169
https://orcid.org/0000-0002-1260-777X
https://orcid.org/0000-0002-9418-6656
https://orcid.org/0000-0002-6047-4211
https://orcid.org/0000-0002-7945-005X
https://orcid.org/0000-0003-3681-0649
https://orcid.org/0000-0003-1486-606X
https://orcid.org/0000-0003-2593-7767
https://orcid.org/0000-0001-9236-6621
https://orcid.org/0000-0002-0869-5631
https://orcid.org/0000-0002-1136-6900
Description
Summary:A search for pair production of third-generation scalar leptoquarks and supersymmetric top quark partners, top squarks, in final states involving tau leptons and bottom quarks is presented. The search uses events from a data sample of proton–proton collisions corresponding to an integrated luminosity of 19.7 fb−1, collected with the CMS detector at the LHC with View the MathML sources=8 TeV. The number of observed events is found to be in agreement with the expected standard model background. Third-generation scalar leptoquarks with masses below 740 GeV are excluded at 95% confidence level, assuming a 100% branching fraction for the leptoquark decay to a tau lepton and a bottom quark. In addition, this mass limit applies directly to top squarks decaying via an R-parity violating coupling View the MathML sourceλ333′. The search also considers a similar signature from top squarks undergoing a chargino-mediated decay involving the R-parity violating coupling View the MathML sourceλ3jk′. Each top squark decays to a tau lepton, a bottom quark, and two light quarks. Top squarks in this model with masses below 580 GeV are excluded at 95% confidence level. The constraint on the leptoquark mass is the most stringent to date, and this is the first search for top squarks decaying via sourceλ3jk′