Murray Gell-Mann quarks for Muster Mark!" book 2, episode 4). Zweig had referred to the particles as "aces", but Gell-Mann's name caught on. Quarks, antiquarks, and gluons were soon established as the underlying elementary objects in the study of the structure of hadrons. He was awarded a Nobel Prize in physics in 1969 for his contributions and discoveries concerning the classification of elementary particles and their interactions. In 1972 he and Harald Fritzsch introduced the conserved quantum number "color charge", and later, together with Heinrich Leutwyler, they coined the term quantum chromodynamics (QCD) as the gauge theory of the strong interaction. The
Particle zoo as the Standard Model, and includes quarks, bosons and leptons. Particle zoo In particle physics, the term particle zoo is used colloquially to describe a relatively extensive list of the then known "elementary particles" by comparison to the variety of species in a zoo. In the history of particle physics, the situation was particularly confusing in the late 1960s. Before the discovery of quarks, hundreds of strongly interacting particles (hadrons) were known, and believed to be distinct elementary particles in their own right. It was later discovered that they were not elementary particles, but rather composites of the quarks. The