  A search for pair production of first and second generation leptoquarks is
performed in final states containing either two charged leptons and two jets,
or one charged lepton, one neutrino and two jets, using proton-proton collision
data at sqrt(s) = 8 TeV. The data, corresponding to an integrated luminosity of
19.7 inverse femtobarns were recorded with the CMS detector at the LHC.
First-generation scalar leptoquarks with masses less than 1010 (850) GeV are
excluded for beta = 1.0 (0.5), where beta is the branching fraction of a
leptoquark decaying to a charged lepton and a quark. Similarly,
second-generation scalar leptoquarks with masses less than 1080 (760) GeV are
excluded for beta = 1.0 (0.5). Mass limits are also set for vector leptoquark
production scenarios with anomalous vector couplings, and for R-parity
violating supersymmetric scenarios of top squark pair production resulting in
similar final-state signatures. These are the most stringent limits placed on
the masses of leptoquarks and RPV top squarks to date.
