High-mass final states in particle physics refer to the study of events in which particles with large masses are produced in high-energy collisions. These final states are of particular interest in the search for new physics beyond the Standard Model, as they may contain evidence of exotic particles or interactions that are not predicted by current theories. Experimental techniques such as the Large Hadron Collider (LHC) are used to study high-mass final states by colliding particles at very high energies and analyzing the particles produced in the resulting collisions. The study of high-mass final states allows physicists to test and refine the current understanding of fundamental particles and forces in nature.