In collisions between protons at the Large Hadron Collider (LHC), pairs of top quarks—the heaviest known elementary particles—are frequently produced along with other heavy quarks, including bottom and charm quarks. These collision events can provide physicists with valuable insights into quantum chromodynamics (QCD), the theory that describes the strong force. Precisely determining the production rates (or "cross-sections") of these processes also enables researchers to more effectively distinguish them from rarer phenomena.