"The clear observation of so many species of well-known particles, ranging from common to quite rare ones, indicates that the RHIC detectors are working spectacularly and that the real exploration can begin," said William Zajc, scientific spokesperson for RHIC's PHENIX detector, in a prepared statement. Zajc is one of the nearly 1,000 physicists working on RHIC.

Physicists who studied the debris streaming from the collisions concluded that densities more than 20 times higher than those within the nuclei of ordinary matter had been produced. Temperatures in the compressed matter topped 1 trillion degrees. The Brookhaven scientists said measurements at the accelerator, if confirmed, indicate they produced matter with a density approaching two times the record announced last year at the CERN particle physics laboratory in Geneva, Switzerland.

The news came at the Quark Matter 2001 Conference at Stony Brook University, where nearly 700 physicists from around the world gathered to hear news about the recently opened U.S. Department of Energy laboratory in New York.

Brookhaven scientists are searching for evidence of a transition to a new phase of nuclear matter called the quark-gluon plasma (QGP), which scientists think last existed at the beginning of the universe and evolved into the matter of today's world. That transition is roughly analogous to boiling water when it starts to create steam. One of the things the scientists hope to find is the "boiling point," the energy density at which the transition takes place.

To do this, the RHIC scientists have built a machine capable of accelerating and colliding gold ions (atoms stripped of their electrons) at nearly the speed of light. So far, RHIC has produced more than 200 million gold ion collisions.

RHIC's four experimental teams -- one for each of the collider's detectors -- have just begun to focus their "microscopes" on these first collisions.

Among the findings so far:

• The pressure created in the first moments of the collisions causes the subatomic debris in the aftermath to flow in an elliptical pattern much more strongly than has been seen before.
• The number of subatomic particles created by each colliding proton and neutron inside the gold ions is much higher than in similar collisions of two protons at the same energy.