Pitt physicist in Switzerland at restart of huge collider
Share with others:
Joe Boudreau was on sabbatical in France last weekend -- in Marseilles, to be exact -- when he got wind of excitement astir at the European Organization for Nuclear Research (or CERN) in nearby Switzerland.
So the University of Pittsburgh physics and astronomy professor hopped a train to Geneva, where he witnessed an important milestone in the development of the Large Hadron Collider, which he's worked on for years.
"There is a huge amount of excitement here with the fact that we are looking at collisions [of particles]," Dr. Boudreau said. "That is exciting for lots of people."
The LHC, as it is known, will help scientists understand the structure of matter at the highest energies so "we can understand processes that shaped the universe 13 billion years ago."
The $10 billion LHC project involving 8,000 scientists from 150 institutions and 40 nations represents the world's longest and most powerful particle accelerator.
Particles were circulated without collisions last year inside the 17-mile underground loop that straddles the Swiss and French border. But problems with its system of magnets required a year of repairs.
Colliders use magnets to accelerate streams of protons or lead ions in opposite directions inside an underground loop. Once particles approach the speed of light in the LHC, the beams of particles will be steered together inside "experiments," where their collisions will produce new particles and energies to be measured and analyzed. The results will help confirm or confound "the standard model of particle physics" that describes the physical structure of the universe.
With last weekend's startup of the LHC, CERN says "our understanding of the universe is about to change."
"It will revolutionise our understanding, from the minuscule world deep within atoms to the vastness of the universe," it states on its Web site at www.cern.ch/.
Since the LHC was activated last weekend 100 particle collisions at low energy levels have been confirmed. The next goal is to ramp up energy levels in coming months to produce collisions at speed and luminosity levels never before produced.
But it could be years before the LHC reaches design specifications to produce particle collisions that replicate what occurred nanoseconds after the Big Bang. For now, the standard model includes four known particles with a fifth, the Higgs boson, yet to be proven. The Higgs boson is thought to provide mass to other particles. There's further hope the LHC can unravel other mysteries of the universe, including dark matter, dark energy and gravitational force.
Dr. Boudreau developed monitoring software inside the Atlas Experiment -- one of the two experiments inside the LHC where collisions can be measured and analyzed.
Noting his good luck at being in Marseilles when the LHC was restarted, Dr. Boudreau said he and nearly 3,000 scientists spent the week analyzing results of last week's collisions. He also verified that the monitoring technology he developed is working to record and analyze the collisions. Images from his technology are displayed on the Atlas Experiment Web site, www.atlas.ch.
"It's a very exuberant period for people," he said. "But we've seen collisions before. We want to see the higher energy stuff."
That will occur when the LHC reaches 14,000 GeV -- an energy level more than seven times higher than any particle accelerator has reached. Then physicists will have a better chance to prove whether or not the Higgs boson actually exists. If it doesn't exist, "the standard model will not stand."
"Soon we will have the highest energies in the world," Dr. Boudreau said. "Hopefully, we will see physical results."
He's but one of many Pittsburgh scientists who have developed technology for the LHC. A team lead by Wilfred Cleland, a Pitt emeritus professor of physics, developed the liquid-argon calorimeter inside the Atlas Experiment that measures, among other things, collision energies. Pitt physicists Vladimir Savinov and James A. Mueller also have worked on the Atlas Experiment.
A Carnegie Mellon University team has focused for 15 years on CMS -- the other "experiment" inside the LHC that detects and measures particle collisions.
Dr. Thomas Ferguson, a CMU professor of physics, said LHC's startup provides physicists 15 minutes of fame.
His CMU team produced and tested 180,000 channels of electronics used in a particle-detection system in the CMS Experiment. They also helped to install the detector, do calibrations and monitor the technology in operation. Professors James Russ, Helmut Vogel and Manfred Paulini, along with post-doctoral and graduate students are members of CMU's team.
When the LHC operated successfully last week, Dr. Ferguson said, he breathed "a deep sigh of relief."
"After 15 years, finally," he said. "It's exciting, after waiting so long and being frustrated so many times."
Three to five years is the most realistic time frame to see "some fantastic thing" from the LHC.
"But if we're really lucky, and nature smiles upon us," Dr. Ferguson said, "it will take less time."
First Published November 28, 2009 12:00 am