The protons and neutrons that form atomic nuclei are composed of three up or down quarks. Up and down quarks are a million ...

High-energy collisions between protons at the LHC routinely produce top quark–antiquark pairs (tt-bar). Measuring the probability, or cross section, of tt-bar production is both an important ...

In the case of smashing electrons into positrons, the pair annihilate and release a quark and an antiquark. The two quarks are unable to escape each other — the farther they try to move apart ...

Top observation CERN’s ATLAS experiment has confirmed that heavy quark–antiquark pairs are created in the collision of lead ions. (Courtesy: CERN/ATLAS Collaboration) Physicists working on the ATLAS ...

They are typically observed in mesons, which can contain different combinations of flavors as quark-antiquark pairs. The last of these, the top quark, was theorized in 1973 by Makoto Kobayashi and ...

However, these quark–antiquark pairs are far less sensitive to the electroweak interaction and do not tell us about origins of symmetry breaking nearly as effectively as single top quarks. To work ...

The hypothetical particle, known as toponium, would be the result of merging a top quark and antiquark as well as the last missing example of quark-antiquark states known as quarkonium.

But there are also particles called mesons that are made of one quark and one antiquark. They too have no color, so it stands that there must exist an antiblue, antigreen, and antired. Gluons ...

Such “extrinsic” quarks are created when gluons, particles that help “glue” the quarks together inside protons, split into quark-antiquark pairs. Extrinsic quarks aren’t fundamental to ...