New physics in interplay with top quarks: bump hunting in topquark-pair production with two additional quarks at the CMS experiment

With the discovery of the Higgs boson in 2012 at the Large Hadron
Collider, the last missing particle as predicted by the standard model
(SM) of particle physics was discovered. Nevertheless, there are
several open questions for which the SM lacks a suitable
explanation. An example is the question as to why the top quark is
significantly heavier than all other known elementary particles of the
SM. Many theories involving new physics try to explain this heavy
mass by a new particle that mostly or even exclusively decays to the
top and bottom quark and that has not been discovered yet.
Depending on the chosen new physics model, this new particle can
reach masses between a few hundreds of GeV and several TeV.
Many of these models can be covered simultaneously by a so-called
"bump hunt" search, a search for a heavy resonance in the invariant
mass spectrum of events that contain four top or bottom quarks
produced in proton-proton collisions. As these events are highly
energetic and their invariant mass spectrum has not been calculated
so far, such an analysis is challenging, but yet promising for finding
new heavy particles. For this analysis, the Run 3 data that will be
recorded by the CMS experiment in the upcoming years is suitable,
as around a million top-quark-pair events with two additional quarks
are expected to be produced, thus providing sufficient statistics for
the search.