Physicists begin to see data from "Big Bang Machine"

Three physicists from Iowa State University have started to see real data from the Large Hadron Collider, which is the planet's biggest science experiment.

The multibillion-dollar collider made international news on September 10, 2008, when it sent its first beam of protons around 17 miles of underground tunnel near Geneva, Switzerland.

But breakdowns in the machine's high-current electrical connections forced a complete shutdown for more than a year of repairs and tests.

Physicists from around the world cheered on November 20, 2009, when the collider once again sent protons racing through its tunnel.

Three days later, the machine recorded its first proton-proton collisions. And on November 30, it set a new world record when it accelerated two beams of protons to a total energy of 2.36 trillion electron volts.

Physicists at CERN, the European Organization for Nuclear Research, shut down the collider on December 16 to prepare for even higher energy collisions later this year.

"The data look just beautiful," said Soeren Prell, an Iowa State associate professor of physics and astronomy.

Prell has been looking at the first data recorded with the ATLAS experiment's silicon pixel detector.

The pixel detector is the innermost part of ATLAS, one of two giant, general purpose detectors at the collider.

ATLAS will measure the paths, energies and identities of the particles created when protons or lead ions collide at unprecedented energies.

The pixel detector uses 80 million pixels to make precise measurements as close to the particle collisions as possible.

Prell said the pixel detector is already sending physicists fairly clean data with very little background noise.

So far, the experiment's analysis system has been able to keep up with the data.

But that's going to be a bigger challenge when the collider is turned back on in February and begins running at higher energies and much higher collision rates.

"One of the concerns I've had is whether we'll be able to handle the data loads we're expecting," said Jim Cochran, an associate professor of physics and astronomy, who is the ATLAS experiment's analysis support manager for the United States.

"We have to have our computing systems optimized so we can do it. We've already had 700,000 collision events, and that's nothing compared to what's coming," he added.

According to Chunhui Chen, an assistant professor of physics and astronomy, "This is a very big moment. Potentially, we'll be able to see some new physics."

That could include the Higgs boson, a particle predicted by the Standard Model of particle physics, and big physics questions about matter and antimatter, dark matter, supersymmetry, and extra dimensions.