Abstract
The Standard Model is an incomplete theory of nature. Numerous
extensions of the Standard Model predict the existence of leptoquarks (LQ), color-triplet
bosons which carry both baryon and lepton number. This dissertation presents the results of
a search for pair production of first generation scalar leptoquarks in the eMETjj final
state. The search is performed in pp collisions corresponding to an integrated luminosity of
1.03 fb^-1, at a center-of-mass energy s^1/2 = 7 TeV, recorded with the ATLAS detector at the
LHC. A multivariate discriminant is used to distinguish signal-like events from
background-like events. Observations are consistent with expectations from Standard Model
backgrounds, thus limits on allowed LQ mass are determined. First generation scalar
leptoquarks with mass m < 558 GeV are excluded at a 95% confidence level for Β =
BR(LQ % → eq) = 0.5. When combined with a complimentary search in the eejj final
state,
leptoquarks with mass m < 607 (660) GeV are excluded for Β = 0.5 (1.0). These are
the strongest limits in existence.
Description
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