Canadian scientist gives energizing talk on particle research project
World's biggest accelerator set to launch in May

Greg Beneteau

A Canadian researcher with one of world's largest cooperative science experiments shared his insights with the Guelph community last Thursday night.

Robert Orr, a physics professor at the University of Toronto and one of the minds behind Canada's contribution to a massive particle accelerator called the Large Hadron Collider, or LHC, talked about the project at a public event organized by the Ontario-based Centre for Inquiry and sponsored by the Guelph Skeptics Society, the Astronomy Club and the Physics Club.

A joint scientific venture co-ordinated by European scientific research agency CERN involving 80 countries and thousands of researchers, the LHC is a circular beam path 27 kilometers in circumference assembled piece-by-piece in a tunnel 100 metres underground, straddling the border between Switzerland and France.

The word "largest" comes up a lot when discussing the LHC. It's the largest machine of its type in the world, sending protons flying around the track at close to the speed of light, kept on course by 9,300 superconducting magnets cooled to –271 Celsius in order to reduce electrical resistance. (This also makes the LHC "the world's largest fridge," according to CERN's website).

Experiments will be run in the world's largest particle detector, with data collected by the world's largest supercomputer – enough to fill 100,000 DVD's per year.

In an accelerator, Orr explained that the same process used in the destructive force of nuclear weapons – a conversion of matter into energy as per Einstein's famous equation E=mc² – is used in reverse, allowing scientists to create a small amount of new matter out of highly energized particles. "Basically what we do is we take protons with enormous kinetic energy and bang them together, and that kinetic energy is tucked into the mass of the new particles," he said.

This process allows scientists to search for particles that don't interact with ordinary matter by comparing energy from the input particles with energy of the known output products and looking for a shortfall - "Something we don't see that carries the energy away," Orr explained.

The first "something" that CERN scientists will be looking for is the Higgs Boson, a fundamental particle believed to be responsible for giving other particles - including itself - a non-zero mass by exerting a field that slows them down much like light passing through glass.

"We think that the Higgs field is like glass that permeates the whole universe, and the propagation of any particle through this glass is what we see as mass," Orr said. "This sounds like a nice theory, but it implies that which should be able to make Higgs Bosons, not just draw little diagrams of them and calculate them out."

By observing how the simplest constituents of matter and energy recombine after being forced apart by the accelerator, researchers can also create conditions similar to shortly after the Big Bang and test theories about how the universe formed.

As a principal investigator for the National Sciences and Engineering Research Council (NSERC) who has worked on particle physics projects in Japan and the U.S, Orr has spent the last thirteen years coordinating Canada's contribution to ATLAS, the detector that will search for the Higgs Boson – and possibly more as-yet undiscovered subatomic particles.

Canada's contribution to the €3 billion EUR, or $4.5 billion CDN, construction of the LHC and ATLAS amounts to about $40 million. The University of Toronto is one of a dozen institutions across Canada involved in the project and was responsible for building one of the energy measurement devices called a calorimeter used in ATLAS.

Other institutions such as the Tri-University Meson Facility (TRIUMF) in British Colombia constructed superconducting magnets the size of transport trucks.

With the LHC set to go online in May, Orr expressed anticipation that the project would "revolutionize" out understanding of the universe and hoped to continue his outreach programs to explain the importance of such programs to ordinary Canadians. "We don't do it for our own edification," he said. " We do it so that people around the world will have access to our research and benefit from it."

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