  Large classes of new physics theories predict the existence of new scalar
states, commonly dubbed sgluons, lying in the adjoint representation of the QCD
gauge group. Since these new fields are expected to decay into colored Standard
Model particles, and in particular into one or two top quarks, these theories
predict a possible enhancement of the hadroproduction rate associated with
multitop final states. We therefore investigate multitop events produced at the
Large Hadron Collider, running at a center-of-mass energy of 8 TeV, and employ
those events to probe the possible existence of color adjoint scalar particles.
We first construct a simplified effective field theory motivated by R-symmetric
supersymmetric models where sgluon fields decay dominantly into top quarks. We
then use this model to analyze the sensitivity of the Large Hadron Collider in
both a multilepton plus jets and a single lepton plus jets channel. After
having based our event selection strategy on the possible presence of two,
three and four top quarks in the final state, we find that sgluon-induced new
physics contributions to multitop cross sections as low as 10-100 fb can be
excluded at the 95% confidence level, assuming an integrated luminosity of 20
inverse fb. Equivalently, sgluon masses of about 500-700 GeV can be reached for
several classes of benchmark scenarios.
