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A TRIUMF of science
by Matthew Claxton-contributing writer
Walter Loveland has a cautiously pleased look on his face. A big man with grey hair, wearing a colourful shirt and glasses, he could be a retiree on vacation. In fact, he is a visiting scientist at the world's biggest cyclotron at TRIUMF, hidden away at UBC.
It's a big day for him. The nuclear scientist has begun an experiment he's wanted to try since 1999, and everything is working well so far.
"You have to stay a little cool," he says, settling into a chair in his office. "You don't want to anticipate."
Loveland is pushing TRIUMF to its limits. Below him under a few dozen yards of concrete, TRIUMF's massive cyclotron, which is essentially a massive 4,000-ton set of magnets, fires off a beam of atomic particles. Invisible to the human eye, the beam creates 2,200 Lithium 11 atoms per second from a slab of tantalum, a hard, heavy metal.
The power generating the beam is double anything attempted before. The last time Loveland tried this experiment, at an American lab, the best rate possible from such a beam was three atoms per second.
"TRIUMF is really the only place you can do this experiment," he says.
Loveland would know. On the faculty of Oregon State University, he travels frequently to the world's top labs, seeking the machinery that can run his experiments. Fascinated with chemistry since he was a teenager, he has spent his career unlocking its secrets, taking time out to write a definitive textbook on the subject with a Nobel Prize winner. And he's typical of the kind of people who come to TRIUMF.
Nestled in the woods near Southwest Marine Drive, TRIUMF is barely visible to the outside world. Once discovered, it looks like a modest 1970s institutional building, surrounded by a cluster of newer structures and a few portables.
But inside the main building, TRIUMF's interior, looking much like a large airplane hangar or factory floor, is filled with machines. TRIUMF's heart, the massive cyclotron, is buried under giant slabs of concrete. But other machines sit cheek-by-jowl, most of them made of gleaming machined steel. Others are painted vivid orange or purple. Most are in constant operation, because TRIUMF is a busy place, with its reputation firmly established in the world of fundamental physics research.
New machines and new projects are unfolding. This spring, TRIUMF announced it is now the highest-power creator of exotic atoms in the world. Already a major draw for scientists from around the world for cutting edge research in physics and chemistry, and having found practical use in both computer science and medicine, the new projects will attract even more attention to TRIUMF, drawing more scientists like Loveland to the woods of UBC.
For all its size, and the ambitious scale of the experiments conducted here, TRIUMF is a quiet place. Aside from the hum of electricity and the whir of cooling fans, there is little noise or activity. A few technicians appear from time to time, checking things over, but the real action is on the level of subatomic particles. Beams are constantly, silently moving through the long, centipede-like accelerators that run across the building's floor.
In other corners of the complex, there are odder machines. A giant purple cube sits off to one side. Signs warning of X-rays are posted against some doors. A hollow half of a sphere, used to detect gamma rays, will look familiar to anyone who saw The Hulk, in which a similar device changed a scientist into a raging monster.
So far, no scientists at TRIUMF have turned into bright green giants, but staff and visitors are issued small radiation detectors when they enter. In the three decades TRIUMF has been open, no one has ever received a detectable does of radiation.
The heart of TRIUMF is the cyclotron, buried under giant concrete blocks stacked like a giant's tomb. The largest cyclotron in the world, it is best understood as a set of massive electromagnets. The magnets guide hydrogen atoms in a spiral until they are torn to pieces by radiofrequency fields. The atom's core of protons becomes a high-energy beam.
The beam fired for Loveland's experiment is being directed at a slab of tantalum. When the beam strikes the target, the high energy reaction creates numerous other atoms, many of them exotic, shortlived radioisotopes.
Some of those, the Lithium 11 that interests Loveland, are collected and fired off as a new beam, at a second target made of zinc foil. After the zinc has been pounded by the lithium for several days, the foil will be broken down and chemically analyzed.
The object of all this work, study and effort is to determine if Lithium 11 behaves differently from its more common cousin, Lithium 9. Lithium 11 has what is called a "halo nucleus," and it's about as wide as a much heavier lead atom.
The question Loveland wants answered is, when Lithium 11 hits another atom, does it behave like a big, light beach ball, or like a tiny, dense golf ball? Will the halo change the way the atom acts?
"It's an interesting question of whether these things fuse," Loveland says. If they do, it could mean scientists will have the ability to create a whole new range of experiments in physics and chemistry.
"The other is just understanding this very fragile structure," he says.
Is it important science?
"It's not going to keep people awake at night in Point Grey," admits Marcello Pavan, TRIUMF's science education outreach coordinator. But for the team of researchers Loveland has brought with him from Oregon to help with the experiment, it might reveal a little more about the way the universe works.
In the experiment's control room, above the main floor looking down onto the machinery, things are considerably more mundane than down on TRIUMF's main floor. All the trappings of modern scientific enterprise-coffee, take out food, computers and sleep-deprived students-are present.
For the next two weeks, the team members will take shifts to watch two lines moving across a computer monitor screen. If both lines are steady, it means everything is OK. If not, something has broken or gone wrong.
"If something goes wrong, then we jump into action," says grad student Pete Sprunger. The rest of the time, they catch up on homework.
The team members admit they have trouble telling friends and relatives what they do. The gulf between years of scientific training and the mainstream can be wide.
Attukalathil Vinodkumar, a post doctoral researcher, once tried to explain a fusion experiment to one of his non-scientist teachers.
The explanation didn't stick.
Some people view what he does almost like magic.
"It's like an alchemist type of thing," Vinodkumar says.
Despite the fact that their team is working with a multi-million dollar device, they aren't staying in the lap of luxury.
Loveland and the students share a basement apartment near UBC, sleeping on air mattresses and trying to keep expenses under $25 a day, per person. The monastic, on-the-road lifestyle is called "suitcase science," and it's just what physicists must do if they want to work on the best machines around the world.
"Some scientists are driven," says Dr. Ewart Blackmore, the head of TRIUMF's accelerator technology group and one of the longest serving staff members at the facility. He's seen hundreds of scientists come through TRIUMF since it first opened its doors in the early 1970s.
"They want to learn. They have burning questions and they want to go out and answer them."
The hands-on approach, refusing to delegate even the mundane tasks to technicians, is also typical, he says.
"You're doing something that in many cases has not been done before."
TRIUMF is one of the elder statesmen of particle physics facilities.
Blackmore was a grad student in the UBC physics department when the discussions about building a cyclotron first began in the late 1960s. The field of research was considered trendy at the time. The University of British Columbia, the University of Victoria and then-new kid on the block Simon Fraser University put together their resources to lobby for federal funding.
The team-up gave the facility its name, which stands for Tri-University Meson Factory. The University of Alberta had joined the team by the time construction started in the early 1970s, but the name stuck.
"Quadrumf and various other things didn't work very well," Blackmore says.
Blackmore joined the TRIUMF team in 1969. Between then and 1971, about 100 people were hired and told to build a cyclotron larger than any that had ever existed.
"We all sort of learned on the job," Blackmore says.
With a Phd in nuclear physics and an engineering degree, Blackmore was involved on the theoretical and practical sides of the project. He has seen TRIUMF grow from its beginnings into an enterprise with a $54 million annual budget, $40 million of which comes from the National Research Council.
Most of the budget goes to the wages of the 450 full-time staff members. The 300 scientists visiting at any one time draw their funding from other grants.
A significant amount of cash goes towards power bills.
"We have a huge electricity bill," Pavan says. "We get specially conditioned electricity from B.C. Hydro."
That power allows scientists to create the same kind of reactions that happen inside a star, to detect changes in particles smaller than atoms. The beam lines are now oversubscribed, with long waiting lists for scientific projects.
"There's more people that want to do their physics here than can possibly be accommodated," says Pavan.
The facility was designed to do basic research with no known practical application. Even before the first beam was generated in 1974, however, scientists were starting to think of real-world uses for TRIUMF.
TRIUMF is composed largely of projects and devices that were unplanned when it began. That is the way basic research works, Blackmore says. You never know whether you will find out something that is simply interesting, or if it will have major implications for technology or medicine.
Blackmore likens the basic research at TRIUMF to the research that created the first transistor half a century ago. Transistors replaced bulky vacuum tubes in electronics. They got smaller and smaller, until they were printed onto microchips by the thousands, and the personal computer era was born.
Computer chips themselves have become a key to another TRIUMF project: testing chips used in orbital satellites. TRIUMF can bathe a chip in simulated cosmic rays, the kind that could burn out an expensive chip and ruin a satellite. Motorola, IBM and other firms test their circuit boards here, blasting them with the equivalent of years of radiation in a few minutes or hours.
Not long after TRIUMF was started, Blackmore and others were working to create isotopes for medical use.
Between the main facilities and three smaller cyclotrons built in recent years by private firm MDA Nordion, material produced at TRIUMF is used in two million medical procedures per year, Blackmore says.
"No one had that as a plan," says Blackmore.
The scientists drawn to TRIUMF come from all over the world, and many of them never leave.
Dr. Tom Ruth came from the United States in 1980, after working at the famous Brookhaven lab. He was recruited to start TRIUMF's positron emission tomography program, and he's been with it ever since.
Now the holder of a Canadian passport, Ruth is in the enviable position of easily explaining to people what he doe: he helps find cancers.
PET scanning involves the creation at TRIUMF of very short-lived radioactive substances. Those substances can be coupled with organic molecules and injected into patients. A scan will then show tumours, brain function or anything else the doctors want to take a look at, and in much greater detail than conventional X-rays or CT scans.
"Politicians buy that," Ruth says. "With basic research, it takes decades before something comes out of it."
Overseeing the PET group at TRIUMF, Ruth has seen huge strides in the discipline. Last year, workers at TRIUMF provided material to help scan 1,500 patients at the Cancer Agency in Vancouver.
The excitement in Ruth's voice is obvious as he talks about the techniques for peering into the inner workings of the brain. His team has recently been working with Parkinson's patients, looking at why the messages from brain to body misfire.
They have also given patients placebos, and watched as their brains changed in response to a completely fictitious medication.
Ruth is especially pleased after the TRIUMF results came on the heels of a major review that said there was no empirical evidence for the placebo effect. The PET scan was the first solid proof that the effect was real and measurable.
Another foreign import who spends a lot of time at TRIUMF is Dr. Tom Pickles.
Unlike most of the other doctors at TRIUMF, Pickles, a lanky and perpetually busy man with an urbane British accent, actually is a medical doctor.
When he spends time at the facility, he sometimes lunches with particle physicists and astrophysicists, but their shop talk passes him by.
"I don't understand all the subatomic physics," he says. "It's difficult for us to understand what they're saying, but a guy with an eye tumour's a little more down to earth."
Trained in England as a radiation oncologist, Pickles came to the facility in 1990 to work both at the physics facility and at the Cancer Centre for a year.
He returned to England, but had liked the work and city so much, he was back by 1992.
Pickles took part in a long-running cancer treatment experiment, using the massive cyclotron to create pion particles, and irradiating brain and prostate tumours. It was thought that pion radiation might be less harmful than the conventional types used for most patients.
The program wrapped up in 1994, after showing that it was no better or worse-and a lot more expensive-than the common therapy. Pickles kept coming back, though, working on a rare type of eye tumour that can be treated using proton radiation.
There are just 200 people diagnosed with ocular melanoma in Canada each year, said Pickles. Those from Manitoba to B.C. can come to TRIUMF.
"A percentage of those, if they don't get the proton therapy, they will have to have the eye removed," he said.
Without treatment or removal, the eye can be destroyed by the cancer. The proton treatment, however, gives excellent results, and Pickles gets to break the good news.
"They're obviously really pleased," he says.
The program has averaged just 10 patients a year. In August 2005, the team celebrated its 100th patient treated and their 10-year anniversary. Compared to other programs, it's a "boutique treatment," Pickles says.
"But it makes a big difference for those 10 patients."
It isn't until after the treatments are done that the patients are given a tour of the building, and see the giant cyclotron that's been treating them.
"They suddenly realize they're sitting at the end of this enormous machine, but they take it in stride," Pickles says.
The days when cancer researchers use TRIUMF for their work may be drawing to a close. Cheaper linear accelerators, built for a few million dollars, can do almost anything TRIUMF can. Meanwhile, there is the problem of getting access to the machines, which are constantly oversubscribed by scientists.
"It's a busy physics research establishment," Pickles says. "It's not a hospital."
For the scientists who have put a lifetime into the place, there is no real end to the things they can do with the facility.
"I have no trouble coming into work," Ruth says. "I feel a very fortunate person."
He has no plans to ever stop working at TRIUMF, saying he'll keep coming back "until they get tired of me."
Blackmore has seen that happen before, with many of his former colleagues still coming by regularly to run experiments or lend a hand. Half of all the people who have left still have official status at TRIUMF.
"Like most physicists, we don't retire, we just stop getting paid," he says. "It's sort of like having a hobby."
Blackmore is hoping to head down that road soon.
"I'll hopefully get rid of all my management jobs," he says, gleefully. Then he can go back to pure science, like that practiced by the team from Oregon.
Two weeks after the experiment began, Loveland's cautious optimism has not been rewarded.
"One of the pumps on the proton machine went out," he says. That resulted in a delay.
Worse than that, the powerful beam strength proved not to be quite powerful enough. Despite getting 100 microamperes out of the beam, there wasn't enough strength to detect whether the Lithium 11 had fused.
It's a disappointing result, as the team will go home without worthwhile data. Loveland, however, is already thinking about other ways to try the experiment, and about new experiments.
His next project will be to try a reaction with lead 208, he says. For a suitcase scientist, there is always another project, another lab somewhere in the world to visit.
"We're still discovering where the ends of the Periodic Table are," he says.
While he leaves TRIUMF without the answer he was looking for, the locals and the next batch of experimenters are pleased. They'll have a new tool, developed for Loveland's team, to play with, as the work at TRIUMF goes on.
published on 08/11/2006
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