Researchers at Berkeley Lab and their collaborators have honed a way to probe the quark-gluon plasma, the kind of matter that dominated the universe immediately after the big bang.
By combining data from two high-energy accelerators, nuclear scientists have refined the measurement of a remarkable property of exotic matter known as quark-gluon plasma. The findings reveal new aspects of the ultra-hot, “perfect fluid” that give clues to the state of the young universe just microseconds after the big bang. (more…)
New Detector System from Berkeley Lab for Quark-Gluon Plasma Studies May Lead to Better Understanding of Early Universe
In the first few microseconds after the big bang, the universe was a superhot, superdense primordial soup of “quarks” and “gluons,” particles of matter and carriers of force respectively. This quark-gluon plasma cooled almost instantly but it’s brief existence set the stage for the universe we know today. To better understand how our universe evolved, scientists are re-creating a quark-gluon plasma in giant particle accelerators such as the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL), where an elaborate experiment called “STAR,” for Solenoidal Tracker at RHIC, has been collecting and analyzing data for the past decade. The STAR experiment is now poised for a major upgrade with the introduction of a new particle detector system, called the “Heavy Flavor Tracker,” that is the most advanced of its kind in the world. (more…)
*By comparing theory with data from STAR, Berkeley Lab scientists and their colleagues map phase changes in the quark-gluon plasma*
In its infancy, when the universe was a few millionths of a second old, the elemental constituents of matter moved freely in a hot, dense soup of quarks and gluons. As the universe expanded, this quark–gluon plasma quickly cooled, and protons and neutrons and other forms of normal matter “froze out”: the quarks became bound together by the exchange of gluons, the carriers of the color force.
“The theory that describes the color force is called quantum chromodynamics, or QCD,” says Nu Xu of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), the spokesperson for the STAR experiment at the Relativistic Heavy Ion Collider (RHIC) at DOE’s Brookhaven National Laboratory. “QCD has been extremely successful at explaining interactions of quarks and gluons at short distances, such as high-energy proton and antiproton collisions at Fermi National Accelerator Laboratory. But in bulk collections of matter – including the quark-gluon plasma – at longer distances or smaller momentum transfer, an approach called lattice gauge theory has to be used.” (more…)
