Hadron Collider detects 'Big Bang' matter

A phase of matter created moments after the Big Bang is thought to have been detected at the Large Hadron Collider in Switzerland.

"Striking" evidence of a quark-gluon plasma has been observed by a team of researchers, including Canadians, at the facility near Geneva,the European Organization for Nuclear Research(CERN) announced Friday.

"People have been searching for evidence of this for decades," Canadian physicist Richard Teuschersaid Friday from CERN's laboratory. "What's exciting is if this is really true [it's] the first unambiguous measurement of this condition of the early universe."

The results of the experiment by an international collaboration called ATLAS were accepted Friday morning for publication in the scientific journal Physical Review Letters, less than 24 hours after it was submitted, said Teuscher, a research scientist at the Canadian Institute for Particle Physics and a physics professor at the University of Toronto.

Normally, the peer review process takes weeks or months, added Teuscher, a member of ATLAS who did some of the data analysis for the experiment.

Physicists theorize that a few hundred millionths of a second after the Big Bang (about 14 billion years ago), the universe was made of a quark-gluon plasma an extremely hotsoup of very tiny subatomic particles.

The Large Hadron Collider produces extremely high-energy collisions of larger particles, mimicking the Big Bang and potentially reproducing the types of matter that existed during the early moments of the universe.

In this case, researchers spent three weeks smashing leadionsinto one another and measuring the resulting signals. Ions are particles produced byadding or removing electronsfrom atoms. They are charged and can therefore be propelled by an electromagnetic field inside a particle accelerator or collider.

Teuscher likened the colliding ions to two bean bags crashing at extremely high speed, causing their contents to spray out.

"But it doesn't just spray out randomly all over the place," he added.

Instead, two cones or "jets" of particles spray out in opposite directions.

Plasma fireball

The lead ions are so massiveand the energy of their collision is so high that itis expected to produce a "fireball" of quark-gluon plasma "something like the fireball produced at the time of the Big Bang."

One of the jets of particles must pass through the fireball to get out the other side, melting in the process.

As predicted, the data shows that in half the collisions, only one of the two jets can be observed, Teuscher said: "The other jet has been blown to smithereens."

The researchers used two different methods to confirm their results. Teuscher added that another experiment called CMS, which uses different detectors, is reporting similar results, although those haven't yet been published.

Peter Krieger, an associate professor of physics at the University of Toronto, saida detector called theforward calorimeter built in Canada by researchers at the University of Toronto and at Carleton University in Ottawa was a key component in the recent discovery.

It helped confirm that the evidence was the result of a certain type of ion collision, where the two ions strike each other head on instead of grazing each other. The head-on collisionreleases more energy, and is therefore thetype thatis predicted to produce a quark-gluon plasma.

Next, ATLAS researchers will be collecting more data and poring through it for different kinds of evidence of quark-gluon plasma.