  A recent study [1] has shown that a simplified model predicting a heavy
scalar of mass 270 GeV ($H$) that decays to a Standard Model (SM) Higgs boson
in association with a scalar singlet of mass 150 GeV ($S$) can accommodate
several anomalous multi-lepton results in proton-proton collisions at the Large
Hadron Collider (LHC). With this in mind, the goal of this article is to
provide a more formal study of a wider set of LHC results pertaining to the
production of multiple leptons. We find that a combination of such results lead
to strong discrepancies between the data and SM Monte Carlo predictions. These
discrepancies appear in corners of the phase-space where different SM processes
dominate, indicating that the potential mismodeling of a single SM process is
unlikely to explain them. Systematic uncertainties from the prediction of SM
processes evaluated with currently available tools seem unable to explain away
these discrepancies. A combination is able to constrain the simplified model's
single degree of freedom $\beta_g^2$, related to the size of the Yukawa
coupling of $H$ to the top quark, to a value of $2.92\pm 0.35$. This is in
contrast to the absence of signal, where $\beta_g=0$. This result is discussed
in the independent contexts of both potential for new physics in the existing
LHC data as well as the limitations of our current understanding of the SM.
That being said, QCD NNLO and EW NLO corrections in di-lepton final states are
not expected to change the conclusions of this study. New results pertaining to
the production of two opposite sign different flavour charged leptons with a
full jet veto further confirm the presence of anomalies in similar corners of
the leptonic phase-space.
