In Science Daily:
A group of 50 international physicists, led by UC Riverside’s Ann Heinson, has detected for the first time a subatomic particle, the top quark, produced without the simultaneous production of its antimatter partner — an extremely rare event. The discovery of the single top quark could help scientists better explain how the universe works and how objects acquire their mass, thereby assisting human understanding of the fundamental nature of the universe.
The heaviest known elementary particle, the top quark has the same mass as a gold atom and is one of the fundamental building blocks of nature. Understood to be an ingredient of the nuclear soup just after the Big Bang, today the top quark does not occur naturally but must be created experimentally in a high-energy particle accelerator, an instrument capable of recreating the conditions of the early universe.
“We’ve been looking for single top quarks for 12 years, and until now no one had seen them,” said Heinson, a research physicist in the Department of Physics and Astronomy. “The detection of single top quarks — we detected 62 in total — will allow us to study the properties of top quarks in ways not accessible before. We are now able to study how the top quark is produced and how it decays. Do these happen as theory says they should” Are new particles affecting what we see” We’re now better positioned to answer such questions.”