Relativistic Heavy Ion Collider
The Relativistic Heavy Ion Collider (RHIC) is the world’s newest facility for basic research in frontier nuclear physics. It is designed to study matter as it existed fractions of a second after the birth of the universe — probably as a plasma of quarks and gluons, the fundamental components of all matter.
RHIC is really two accelerators in one — made of crisscrossing rings of superconducting magnets, enclosed in a tunnel 2.4 miles in circumference. In the two rings, beams of heavy ions are accelerated to nearly the speed of light in opposite directions, held in their orbits by the powerful magnetic fields. The particles collide at six points around the circles where RHIC’s two rings intersect.
Thousands of collisions take place every second, each producing a spray of thousands of subatomic particles. Detectors collect and analyze the collision products, providing physicists worldwide with data to help them investigate the inner workings of matter and the birth of the universe.
In 2005, researchers announced that, using RHIC, they had created a new state of hot, dense matter out of the quarks and gluons that are the basic particles of atomic nuclei, but in a state quite different and even more remarkable than had been predicted. In peer-reviewed papers summarizing the first three years of RHIC findings, the scientists said that instead of behaving like a gas of free quarks and gluons, as was expected, the matter created in RHIC’s heavy ion collisions appears to be more like a liquid. This new state of matter was dubbed the "perfect" liquid.
The unexpected findings introduced a wide range of opportunity for new scientific discovery regarding the properties of matter at extremes of temperature and density previously inaccessible in a laboratory. See the RHIC website.