WASHINGTON: A team of researchers at the Brookhaven National Laboratory has produced a new state of matter - they call it quark-gluon plasma - which is a hot and dense liquid made of basic atomic particles.
The scientists claim in the early universe, possibly for a brief period after the "big-bang" creation of the universe, all matter would have looked like quark-gluon plasma.
"We have a new state of matter," announced Sam Aronson, associate laboratory director for High Energy and Nuclear Physics at the Laboratory. "We think we are looking at a phenomenon ... in the universe 13 billion years ago when free quarks and gluons ... cooled down to the particles that we know today," he added.
"It's a very important milestone in that it's like we've come ashore and we're on a new continent," said Aronson. "This is a major new feature of this landscape: It's liquid-like and not gas-like."
Quarks and gluons have fascinated scientists, and the accumulated experiments at Brookhaven suggest that these particles, when freed, work together as if part of a flowing liquid instead of in the more random go-it-alone style of a gas.
The new matter was developed using a Relativistic Heavy Ion Collider, a powerful atom smasher. The researchers smashed two gold ions together at speeds, very close to the speed of light. The collision weakened the strong force that usually binds quarks into protons and neutrons, allowing the quarks to roam freely, explained the researchers.
Four scientific papers analyzing data from three years research will be published in the journal Nuclear Physics A.
The new quark-gluon plasma is expected help physicists understand the force that holds protons and neutrons together.
Earlier in 2000, scientists at the CERN particle physics laboratory in Switzerland revealed they had created a quark-gluon plasma, but it was dismissed as premature.
The Relativistic Heavy Ion Collider, or RHIC, is a massive ring-shaped structure visible from space. While there have been definite theories on the state of matter in the early universe, it could not be simulated in a lab environment. RHIC offered an ideal high-energy alternative to test the theory.
Scientists may now be able to work on these results by measuring other properties that behave differently in liquids, heat capacity and speed of sound, for example, and by studying the behavior of infrequent gluon and quark head-ons in the larger collisions.
