protons and pistols: remembering robert wilson

Jen-Luc-Piquant1 [Note: This post originally appeared at our new home at Scientific American.]

One day in 1969, the Congressional Joint Committee on Atomic Energy convened in Washington, DC, to hear testimony from a number of scientists concerning a proposed multimillion dollar particle accelerator to be built in Batavia, Illinois. Physics had enjoyed strong government support for two decades in the wake of the Manhattan Project, which helped bring an end to World War II. But many in Congress simply couldn't see the point of spending all that money on a big machine that didn't seem to benefit US national interests in quite the same way.

During the testimony of physicist Robert Rathburn Wilson — a veteran of the Manhattan Project — then-senator John Pastore bluntly asked, "Is there anything connected with the hopes of this accelerator that in any way involves the security of the country?"

Wilson, to his credit, answered just as bluntly: "No sir, I don't believe so."

"Nothing at all?" Pastore asked.

"Nothing at all."

Pastore pressed further: "It has no value in that respect?"

And then Wilson knocked it out of the park. "It has only to do with the respect with which we regard one another, the dignity of man, our love of culture. It has to do with: Are we good painters, good sculptors, great poets? I mean all the things we really venerate in our country and are patriotic about. It has nothing to do directly with defending our country except to make it worth defending."

Needless to say, the proposed accelerator got its funding, and Fermi National Laboratory was born. Wilson took the lead on the design and construction of the facility, and proved more than up to the task: Fermilab, as it is known today, was completed on time, and under budget. And its scientists went on to make some of the most fundamental discoveries in particle physics, garnering quite a few Nobel Prizes along the way.

I've been thinking about Wilson's zinger of a response to Pastore a lot lately, as economic woes and corresponding budget cuts threaten some pretty major scientific projects. (*cough* James Webb Space Telescope *cough*) We seem to have lost our sense that science, just for the sake of science, adds something unique and valuable to society, beyond the technological advances that it enables. The emphasis these days is always on, "Well, what is it good for?"

It's a fair question, and I'm all for being practical. Those technological advances have been truly extraordinary and have revolutionized every aspect of our lives. But let's not, in the process, devalue the curiosity-driven pursuit of knowledge for its own sake. Science, Wilson realized, is part of what makes a country worth defending, and his life's work reflected that.  

Pistol-Packin' Physicist

Wilson was born in Frontier, Wyoming, in 1914, and growing up in the wild west no doubt gave him his lifelong love of the great outdoors, not to mention that hint of a swagger that was among his many trademarks. "He always had big, wild tales about being a cowboy in Wyoming," Dale Corson, a physicist and longtime friend of Wilson, told the New York Times for Wilson's obituary in 2000. "Most of them turned out to be true." But he also loved to tinker with pumps and vacuum tubes, as a boy, and soon found himself fascinated by the fundamental building blocks of nature — at least, those that were known at the time. "We only had electrons and protons, and you could put those together into atoms in various ways and make the whole universe," he later recalled. "It was a very simple theory that even a dope could understand. I decided then that I wanted to go into physics."

By 1932, he'd found a place in Ernest O. Lawrence's flagship cyclotron laboratory (the "Rad Lab") at the University of California, Berkeley, although he was infamously fired twice: once for losing a rubber seal right before a presentation to a potential donor, and once for accidentally melting a pair of pliers while welding. He was offered his job back both times, but the second time, he opted to leave the Rad Lab and go to Princeton instead.

That's where he was when Oppenheimer chose him to be part of the elite corps of scientists on thee Manhattan Project at Los Alamos National Laboratory, which opened in 1943 under the greatest secrecy. Wilson found himself heading the Cyclotron Group — the youngest group leader in the experimental division. He was reluctant to take the job at first; he wanted to do science, not get bogged down in administration. Oppenheimer asked Enrico Fermi to intervene and persuade Wilson to head the new division.

When Wilson pointed out that Fermi himself would never accept such a position, and he was merely following his mentor's example, Fermi shot back, "It's something you have to earn, and you're not Fermi yet." In the end, Fermi convinced him to take the job by promising to meet with Wilson every Friday to talk about the physics being done. In his own account, Wilson admitted, "Sure I sold out — but then everyone has his price, and mine was a few moments each week with Fermi."

Wilson sometimes chafed at the tight security around Los Alamos, occasionally teasing the security guards charged with protecting the spheres of uranium-235. The scientists were conducting delicate experiment to measure the rate at which neutrons multiplied in those sphere, along with a control sphere of regular uranium. Wilson proposed that he be issued a pistol so that he could guard the spheres himself. "After all, I came from Wyoming, where every red-blooded boy learned to shoot before he could walk."

Oppenheimer agreed, but Wilson had to first be certified to ensure he really could handle a pistol. So he was taken to a firing range, given a Colt .38, and subjected to a detailed lecture on how to properly handle and fire the weapon. His instructor then fired six shots at a target before handing the gun to Wilson to try. As Wilson recalls, "I had learned in Wyoming to 'roll' a pistol in order to get a lot of shots off accurately and rapidly. That's just what I did. Most of my shots were closer to the bull's eye than were his."

For all the hijinks, nobody forgot that the work they were doing at Los Alamos was both vital to national defense, and highly dangerous due to the radioactive substances involved. Wilson recalled his own brush with death while assisting a physicist in the Critical Assemblies Group with another experiment to determine when criticality was reached as one stacked a series of enriched uranium hydride cubes. He was surprised, and a bit dismayed, to find that the group didn't rely on the usual elaborate safety devices commonly used at cyclotron facilities at the time. Instead, the physicist arrived with a simple set-up involving a wooden table, a single neutron counter to monitor criticality, and a whole bunch of cubes of enriched uranium hydride.

Wilson watched, rapt, as the physicist started stacking uranium cubes, and then noticed with alarm that the neutron counter wasn't, well, counting. Upon inspection, he discovered that the voltage supply was burnt out. When the counter was turned back on, it lit up immediately, to Wilson's horror. "A few more cubes and the stack would have exceeded criticality and could well have become lethal," he recalled. Furious, Wilson chewed out the physicist, his division leader, and even raged about it to Oppenheimer himself, but he had to leave for Trinity the very next day, so he let the incident drop. Had he stayed and pursued the matter, Wilson believed, "I might have saved the lives of two people. To this day, the incident is on my conscience."

Those two people were Harry K. Daghlian, Jr. and Louis Slotin, both of whom died of radiation sickness after accidents that occurred while conducting critical experiments with a plutonium core — known as "tickling the dragon." Daghlian's death was dramatized to great effect in the 1989 film Fat Man and Little Boy using a fictional character based on him named Michael Merriman (played by John Cusack). In Daghlian's case, the tungsten carbide bricks around the plutonium sphere — designed to act as a radiation shield — were improperly handled. The dose of radiation he received as a result was so high, he died within a mere 28 days of the accident. It's one of the dramatic high points of the film, along with the scene depicting the historical Trinity Test itself:

As Wilson recalled in People magazine on the 50th anniversary of the Trinity Test in 1995:

I was in a bunker 10,000 yards north of Ground Zero, and the wind was blowing in our direction. Minutes after the bomb went off, I began to get apprehensive because a section had peeled off from the mushroom cloud and was coming straight at us. Meanwhile, the doctor was reading that the radiation was much higher than he expected. We had about 10 trucks, so I ordered people to get in them and leave immediately. There were some soldiers stationed outside who told me they had to stay until they were relieved by a military officer, but using a vocabulary everyone could understand, I convinced them to get into a truck. As we left, that cloud of radioactive debris was right on top of us, and it was spooky. We were lucky though. About 25 miles later it came down on a bunch of cattle and turned their hair white.


Architect of Accelerators

After World War II ended, Wilson left Los Alamos to design accelerators at Cornell's Laboratory of Nuclear Studies, culminating in the university's flagship Electron-Positron Storage Ring (CESR). Based on his stellar reputation working with accelerators, in 1967, he took a leave of absence to become director of the National Accelerator Laboratory (renamed Fermilab in 1974), to oversee the construction of what would be the most powerful accelerator then in existence.

"Bob built accelerators because they were the best instruments for doing the physics he wanted to do," Wilson's Cornell colleague, Boyce McDaniel, recalled in 2000. "No one was more aware of the technical subtlety of accelerators, no one more ingenious in practical design, no one paid more attention to their aesthetic qualities. He thought of accelerator builders as the contemporary equivalent of the builders of the great cathedrals in France and Italy. But it was the physics potential that came first."

That aesthetic appreciation carried over into his design for Fermilab's main accelerator ring, although once again, its physics potential came first, with the most cutting-edge, forward-looking technology available. Yet it was intended from the start to be visible from the air, thanks to the construction of a 20-foot-high berm above the entire four-mile-long ring. There was no technical reason for that decision; Wilson just thought it would look nicer.

He also wanted Fermilab to an aesthetically pleasing work environment; he didn't want it to look like a typically sterile government lab. To that end, he made sure he restored part of the surrounding prairie, with ponds and a herd of bison, for good measure. Wilson designed the main building, now known as Wilson Hall in his honor, after being inspired by the medieval cathedral at Beauvais, France — a kind of "cathedral of science," if you will. "When he created Fermilab, it certainly had style," Leon Lederman, who succeeded Wilson as director, recalled. "He was a showman in that sense. He took chances."

Wilson's style and personal creativity extended to abstract sculpture; his work is dotted all over the grounds of Fermilab, such as "Broken Symmetry," an orange-and-black three-span arch that spans one of the Pine Street entrance. It appears asymmetrical from any angle, except when viewed directly from below. He also sculpted "Mobius Strip" (self explanatory), "Tractricious" (made from scrap cryostat tubes from Tevatron magnets), and his most famous, the 32-foot-high "Hyperbolic Obelisk" at the foot of the reflecting pond in front of Wilson Hall. "If I wasn't being creative, I thought I was just wasting my time," Wilson once confessed.

Not that he wasn't first and foremost a pragmatist, mind you, despite his aesthetic sense. Wilson is also known as the "father of proton therapy," thanks to a 1946 paper he published, "Radiological Use of Fast Protons." He'd become interested in researching the effects of radiation damage on the human body as a result of his Los Alamos experiences — especially the deaths of Daghlian and Slotin, which had affected him greatly. Most proton therapy facilities follow the tenets and techniques Wilson established in that groundbreaking paper in their treatment of cancer patients — a peaceful use of a wartime technology, saving lives instead of taking them.

Wilson's name is not as well-known to the general public as that of Albert Einstein, Richard Feynman, Enrico Fermi, or J. Robert Oppenheimer, but he was very much a "physicist's physicist." Bring up his name in a gathering of physicists, and you'll be regaled with everyone's favorite Wilson anecdote — that's how much love and respect he inspired in those who worked with him. And deservedly so: he embodied the perfect balance between aesthetics, curiosity, and pragmatism.

Science isn't just about winning wars, treating cancer, or devising revolutionary new technologies to boost economic markets — although it can and does accomplish all of those things. It's also about the sheer joy of discovery, of pushing the boundaries of human knowledge, as essential a component of the human spirit as the greatest works of art, of music, of literature. And as such, it is worth defending.

Scroll to Top