Searches for scalar leptoquarks in $pp$ collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector

Abstract

Searches for pair-produced scalar leptoquarks are performed using 20 fb${}^{-1}$ of proton-proton collision data provided by the LHC and recorded by the ATLAS detector at $\sqrt{s}=8$ TeV. Events with two electrons (muons) and two or more jets in the final state are used to search for first (second)-generation leptoquarks. The results from two previously published ATLAS analyses are interpreted in terms of third-generation leptoquarks decaying to $b{\nu }_{\tau }\bar{b}\overline{{\nu }_{\tau }}$ and $t{\nu }_{\tau }\bar{t}\overline{{\nu }_{\tau }}$ final states. No statistically significant excess above the Standard Model expectation is observed in any channel and scalar leptoquarks are excluded at 95% CL with masses up to $m_{LQ1}$ < 1050 GeV for first-generation leptoquarks, $m_{LQ2}$ < 1000 GeV for second-generation leptoquarks, $m_{LQ3}<$ 625 GeV for third-generation leptoquarks in the $b{\nu }_{\tau }\bar{b}\overline{{\nu }_{\tau }}$ channel, and 200 $<m_{LQ3}<$ 640 GeV in the $t{\nu }_{\tau }\bar{t}\overline{{\nu }_{\tau }}$ channel.

25 pages plus author list + cover pages (42 pages total), 6 figures, 8 tables, submitted to EPJC, All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/EXOT-2014-03/

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