Large Hadron Collider Completes Round of Experiments, Begins New Phase

November 17, 2010 — International teams of scientists working on an array of high-energy physics research projects with the Large Hadron Collider near Geneva – including several physicists from the University of Virginia's College of Arts & Sciences – are beginning a new set of experiments this month after having completed a seven-month mission colliding protons at the highest levels of energy ever accomplished.

The LHC is housed in a circular, nearly 19-mile tunnel straddling the French-Swiss border. It acts as a sort of racetrack, where scientists and engineers can accelerate protons and ions at nearly the speed of light, in opposite directions, shattering them in the ensuing collisions. The result is trillions of points of data that must be sorted through over the course of years using an international computer grid.

The effort at the LHC, a planned series of thousands of experiments over the next 20 or more years, is intended to solve fundamental mysteries of how the universe began and evolved, how the very structure of matter came about.

The physicists are now colliding lead ions, again at the highest energy levels ever to occur short of the making of the universe after the Big Bang.

By accelerating and smashing lead ions together, researchers are breaking apart the building blocks of atoms to peer inside and see their fundamental structure. They are recreating, in effect, the early post-natal universe, before the advent of atoms and molecules, elements and compounds, before stars and galaxies and planets.

With the recent successful run of experiments, scientists believe the long-term payoff for the multi-billion-dollar facility will be a big-time payday in gained scientific knowledge. New laws of physics are likely to be discovered, and, possibly, "dark matter" may be explained.

Dark matter is a mysterious invisible energy that may make up as much as 80 percent of the universe.

"We've had a beautiful run so far and are beginning to get into unknown territory," said Brad Cox, a U.Va. professor of physics who has been involved with detector design for the LHC and is now deeply into the extraction of physics results on dark matter from the data. "After this heavy ion run and a short maintenance break, we will resume proton-proton operation in February 2011 and possibly continue our around- the-clock operation until the end of 2012, a total of three years of 24-7 operation. 

"At the end of this run, we certainly have a chance to see totally new physics.”

Cox, along with U.Va. physicists Michael Arenton, Sarah Boutle, Sergio Conetti, Robert Hirosky, Alexander Ledovskoy and Christopher Neu, and graduate students Michael Balazs, Brian Francis, Joey Goodell, Chuanzhe Lin, John Wood and Rachel Yohay, helped develop and test components, and commission the Compact Muon Solenoid, one of the two detectors at the LHC.

The United States has contributed $800 million toward the construction of these detectors. They expect to find important physics results in the billion or so interactions that occur each second in the accelerator during operation. U.Va. faculty members in computer science, electrical engineering, the Division of Information Technology and Communications and the radiology department also have contributed time and expertise to the LHC projects.

— By Fariss Samarrai