Single Top Quark (IMAGE) Brown University Caption Brown University joined institutions from around the world to announce on Monday the discovery of the single top quark through the weak nuclear force, shown in this diagram. Credit Fermilab Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.