May 05, 2011
Photo: VOA - K. Farabaugh
US Department of Energy’s Fermilab
A twenty-five year search for one of the keys to understanding the structure of the universe is coming to an end at the U.S. Department of Energy's Fermilab in suburban Chicago. The Tevatron Accelerator, a sub-atomic particle collider, is scheduled to go offline later this year. When that happens, the Large Hadron Collider, or LHC, in Geneva, Switzerland, will fully take over the search for the so-called "God Particle." But, the Tevatron is not going quietly into retirement.
For more than 15 years, scientist Robert Roser has searched for the elusive "Higgs Boson."
"The Higgs Boson is a hypothetical particle that we believe exists to fix a flaw in the standard mode," said Robert Roser. "The standard model, to us, is our mathematical description of how the universe works. The significant flaw in that model is that it doesn't explain mass."
The discovery of the Higgs Boson - known to many as the "God Particle" - could give scientists the answers they seek to many of the biggest questions known to man.
"We're asking the question of how the universe works, and why is it built the way it is built?"
To find the Higgs Boson at Fermilab, scientists use the Tevatron Accelerator to slam protons and anti-protons together. In the stream of data that follows, scientists look for clues that the Higgs Boson exists. So far, they haven't found any such clues. But Roser says they may have found something else.
"As we look at these huge data sets that we've acquired over the 10 years, we're now putting out things that we've learned about that data," he said. "And so what you're seeing here is evidence for perhaps a new particle and there will be other things that will come out over the coming months that will be just as interesting as this."
The discovery of what could be a previously unknown sub-atomic particle could also be the last major accomplishment of the Tevatron.
"All good things will come to an end, and this will be the end for the Tevatron. It's had a glorious career, 25 years, which is very long in the accelerator field," said Pier Oddone.
Pier Oddone is the Director of Fermilab. He says the funding needed to continue the research necessary to find the Higgs Boson, if it exists at all, exceeds Fermilab's $400 million annual budget.
"It is one third the budget of the laboratory in Geneva Switzerland," he said.
The CERN laboratory in Geneva is home to the Large Hadron Collider. Built in collaboration with Fermilab, it is a more powerful device than the Tevatron Accelerator. When the Tevatron goes offline later this year, the focus in this area of physics will finally move from the United States to Europe.
"In this last two decades that has shifted where the facility in Geneva went ahead and built this formidable machine, which we were trying to build in Texas called the Superconducting Supercollider," said Oddone. "We closed ours but the Europeans went ahead with theirs, and that is what has led to this differentiation now in the funding of laboratories."
Even though Fermilab stands to lose some prestige when the Tevatron shuts down, scientists say the U.S. is still be well represented in the field of particle physics. Since the Tevatron began colliding, Robert Roser says it has been an international effort, and it will continue to be one as the search goes on in Geneva.
"There [are] fifteen nations that are participating on this experiment," said Roser. "Roughly 300 of the 600 collaborators on this experiment are from non-U.S. institutions. So it's very much a large multi-national or international collaboration. All big science is these days."
After the Tevatron goes offline, it will continue to play a role at Fermilab. Engineers plan to open previously inaccessible segments of the collider tunnel, where they will display part of the accelerator and detectors in an exhibit the public will be able to visit.