A search is presented for the production of both first- and second-generation scalar leptoquarks with a final state of either two electrons and one jet or two muons and one jet. A data sample of proton-proton collisions at center-of-mass energy sqrt(s) = 8 TeV recorded with the CMS detector corresponds to an integrated luminosity of 19.6 inverse femtobarns. Upper limits are set on both the first- and second-generation leptoquark production cross sections as functions of the leptoquark mass and the leptoquark couplings to a lepton and a quark. Results are compared with theoretical predictions to obtain lower limits on the leptoquark mass. At 95% confidence level, single production of first-generation leptoquarks with a coupling and branching fraction of 1.0 is excluded for masses below 1730 GeV, and second-generation leptoquarks with a coupling and branching fraction of 1.0 is excluded for masses below 530 GeV. These are the best overall limits on the production of first-generation leptoquarks to date.
CMS, Basegmez, S., Beluffi, C., Bondu, O., Bruno, G., Castello, R., Caudron, A., Ceard, L., Da Silveira, G. G., Delaere, C., Favart, D., Forthomme, L., Giammanco, A., Hollar, J., Jafari, A., Jez, P., Komm, M., Lemaitre, V., Mertens, A., et al. (2016). Search for single production of scalar leptoquarks in proton-proton collisions at sqrt(s) = 8 TeV. Physical Review D, D93(3), 32005. https://doi.org/10.1103/PhysRevD.93.032005 (Original work published 2016)