by Tom Clynes
Well, its [sic] time for some plasma pictures. We played around a little with the system and the gas handling with some argon. It took some fidgeiting [sic] with the gas to get a discharge, but not flood the current. We have a few issues, have to hook up the Baratron to see what we’re dealing with inside the chamber, and add a small amount of tubing, etc. to the Deuterium cylinder, but I think we are ready to go for fusion in a couple of days. Here are some pictures of the discharge. We were running at about 5–15 KV without very many x-rays, but they started to shine through the top viewport as the gas was pumped out and the voltage went over 20 KV. The pressure was pumped down to I think somewhere around 5e-7 before we introduced gas.
By sunrise, “Welcome to the Plasma Club!” congratulations were streaming in. Willis, the first to respond, wrote: “This will be a neutron generator when it gets a breath of deuterium.”
Richard Hull wrote, “Nice work . . . Got a real name so I can put you in the Plasma Club?”
“Yes,” the fourteen-year-old replied. “It’s Taylor Wilson.”
But when they ran the test for Phaneuf, who knew plasma better than just about anyone on earth, the professor’s eyebrows came together.
“The shape of that plasma field isn’t quite right,” he said. “See how it’s kind of a funny oblong shape? It needs to be perfectly round. If you can get more symmetry out of your grid structure, that will locate the collision zone closer to the grid’s geometric center. You could probably eke out some detectable fusion from it like it is, but you might as well do it right. I think you should redesign the cage and make it more spherical.”
Unfortunately, the more spherical version of the grid that Taylor and Cline had earlier machined and tested kept collapsing whenever they brought it up to high voltages. They’d changed the design again and again, with the same result.
Then Phaneuf remembered that he’d used a special tungsten-alloy wire for an experiment he’d done at Lawrence Berkeley. The mix of 98 percent tungsten and 2 percent tantalum was specially formulated to prevent that embrittlement. As luck would have it, the next day Phaneuf was flying down to California. He brought back the alloy wire, which Cline and Taylor fabricated into an almost perfectly spherical grid.
“That did the trick,” Taylor says. “It was the key to getting the plasma field right.” With the new grid, they could push the electrical discharge up almost to fusion levels and watch as a clean and almost perfectly round ball of blue-white plasma developed in the middle of the grid.
“I don’t think I’d enjoy hanging out with Einstein,” Taylor said as he led Phaneuf and Brinsmead into the physics building’s elevator. “Too theoretical. I’d be more into meeting Tesla, or Farnsworth—who, by the way, invented the television when he was fourteen, same as me.”
Taylor had wanted to make fusion before his fifteenth birthday, which was coming up in May. He had been pushing hard for months. By early March he was getting more and more anxious, but there was no question he was closer now. All the parts had been either scrounged or built, then tested and assembled and tested again. Over the past few days he’d made some vacuum-tightening tweaks, put the pumps through their paces, and made several test runs with argon. Now they were ready to move into uncharted territory and try for fusion.
Taylor punched in the secret code to enable the elevator to access the physics department’s subbasement. “According to the rules,” Phaneuf said, winking, “you shouldn’t actually have that code.”
Phaneuf unlocked the door to the lab and the three of them entered. Taylor immediately spotted a new canister of oxygen-18, a heavy isotope, next to Phaneuf’s desk.
“No, you can’t have it.” Phaneuf laughed.
Phaneuf had finally broken down a week earlier and suggested a little straightening up. Taylor cleared the area around the machine, moving things to nearby shelves and tables, which further set Taylor’s fusor apart from the rest of the lab. The reactor, surrounded by yellow radiation-warning signs, dominated the far corner of the room.
The three of them went over and took a look at it, their eyes adjusting to the light in the windowless room. The reactor was a far cry from the jumble of ill-fitting and ill-behaving parts that Taylor had tried to piece together in Arkansas in his grandmother’s garage and his father’s Coke plant. It looked elegant, defiant even, a gleaming stainless-steel-and-glass chamber atop a cylindrical trunk bolted to the stout rack and connected to an array of sensors and feeder tubes. Standing on his tippy-toes, Taylor was just tall enough to peer through the window into the reaction chamber, where he could see the golf-ball-size grid of tungsten/tantalum fingers that would, if all went well, cradle the plasma in which the nuclear fusion reactions would occur.
Mounted to the shielding they’d set up around the machine was the video camera they’d scrounged from the closed bank branch, bracketed to the rack and aimed at the reaction chamber. At higher voltages the machine would produce so many x-rays that looking inside the window while it was running—or even standing next to it for a minute or two—would induce acute radiation sickness. Any longer than that would be lethal.
Taylor took Phaneuf through the instrumentation that he’d set up, including a calibrated ion chamber, x-ray detectors, and other survey meters scattered around the room. He had also hooked up a boron-10 trifluoride (BF₃) neutron detector, commonly known in the physics community as “Snoopy.” Snoopy would give them real-time information about neutron generation, but because it was sensitive to electromagnetic interference and other forms of radiation, it wasn’t sufficient to provide actual proof of fusion. For that, they’d set up neutron bubble detectors, cylinders filled with liquid in which bubbles would appear to decisively confirm the presence of the neutrons and prove that a fusion reaction had taken place.
Taylor removed the argon gas cylinder and replaced it with a cylinder of deuterium gas, using the new valve adapter that Cline had machined. He locked the cylinder into place, then moved to the control panel, shielded behind a wall of lead and polyethylene blocks.
“Eh-hem,” Phaneuf said, glancing toward the lead apron and dosimeter hanging on the wall. Taylor smiled and duly put them on, then moved behind the wall, saying, “It’s not like we’ve measured x-rays getting through the lead back here or anything.”
“Our number-one job,” Brinsmead said, “is to keep you safe.”
“Even if it is total overkill,” Taylor mumbled. Though Taylor had grown taller in the past few months, the heavy apron still extended below his knees, giving him a comical look. “And even if I’m the only one in the room with this ridiculous getup.”
“Hey, us old guys are done reproducing,” Phaneuf said.
“Or we never got started,” Brinsmead added, “and don’t plan to!”
By that point, Phaneuf was convinced that Taylor knew everything he needed to know about radiation safety. The apron and the massive amounts of lead shielding were indeed overkill. But Taylor was still growing; his dividing cells were more vulnerable to radiation than the cells of full-grown men. And the test runs had shown that the machine produced a surprisingly high level of x-rays. For Phaneuf, that reinforced the wisdom of continuing the safety overkill.
Apart from giving the apron reminder, though, both Phaneuf and Brinsmead stood back and let Taylor go through all his pre-energizing checks. Then the boy returned to the control panel.
“Okay now, y’all stand back,” Taylor said. As Brinsmead and Phaneuf retreated behind the lead-block wall, Taylor shook the hair out of his eyes, reached toward the controls, and flipped the main switch.
24
* * *
The Neutron Club
TAYLOR TOGGLES ANOTHER SWITCH, energizing the vacuum pumps. He and Brinsmead and Phaneuf watch the gauge as the air is sucked out of the reaction chamber and the pressure decreases to the equivalent of 100,000 feet above sea level . . . then the space station’s orbit . . . then the surface of the moon.
Standing just behind Taylor, Phaneuf peers over the boy
’s left shoulder, Brinsmead over his right.
“Looks like switching out that valve really did the trick,” Phaneuf says. “You’re getting better vacuum than I’ve ever seen.”
Taylor turns a knob to start bringing the voltage up. The temperature moves past 100 degrees C; at this point, any condensation in the chamber would have vaporized and been sucked out.
Taylor brings up the power on the vacuum pumps even more. “And now,” he says, “we’re entering interstellar space . . .”
Brinsmead says, “When you were in your grandma’s garage and you got the idea to try to build this thing, did you ever imagine you’d be at this point, doing what you’re about to do?”
“To be honest, Bill,” Taylor says, “I did. I just didn’t think it would take this long.”
Taylor scans the gauges. “I’m going to open the line and bring in a little deuterium,” he says, “and give the grid a little negative voltage.”
Taylor knew that achieving fusion depended on getting a just-right balance of vacuum, gas supply, and voltage. While Phaneuf was away, he and Brinsmead made several test runs, experimenting with different combinations. “I think he’s really got the parameters optimized now,” Brinsmead tells Phaneuf.
“Ten thousand volts,” Taylor calls out, glancing at the meter. He cranks the voltage knob a little more and checks the instruments. “I’m going to pour on more fuel to balance the pump.
“Twenty thousand volts now, and . . .”—he glances at the video monitor—“we’ve got plasma!”
Sure enough, a pale blue cloud of plasma has appeared, rising and hovering, ghostlike, in the center of the grid. Taylor looks at Phaneuf, then Brinsmead, who nods. “Let’s go for it,” Brinsmead says.
Taylor turns the knob, taking the voltage higher. “I’ve got it up to twenty-five thousand volts now,” Taylor says. “I’m going to outgas it a little and push the voltage up a little bit more.” The power supply crackles.
From behind, Taylor looks like a small Oz kind of figure, his hands darting back and forth, checking gauges, pulling levers, finessing dials. He adjusts the pressure and voltage again while Brinsmead and Phaneuf keep their eyes on the video monitor. They can see the tungsten wires beginning to glow, then brightening to a vivid orange. “When the wires disappear,” Phaneuf says, “that’s when you know you have a lethal radiation field.”
The two men watch the monitor while Taylor concentrates on the controls and gauges, especially Snoopy, the portable neutron detector that they’ve set up just to the side of the lead-block wall, a few feet away.
“We should be getting pretty close to star territory now,” Brinsmead says.
Phaneuf squints at the monitor. Rays of plasma dart between gaps in the now-invisible grid as deuterium atoms, accelerated by the tremendous voltages, begin to collide. The blue-white plasma starts to throw off purple sparklets.
Brinsmead, who’s been watching the neutron detector, suddenly shouts: “We’re getting neutrons!”
Inside the reaction chamber, separated from the outside world by two inches of stainless steel, deuterium atoms are stripped of their electrons and accelerated toward the dense, superheated plasma core at the center. Each second, tens of thousands of these ions collide violently enough to fuse and release tiny amounts of mass-energy as highly energetic neutrons.
In other words, nuclear fusion reactions are taking place.
Taylor smiles ever so slightly and keeps his hands on the controls.
“Let’s see what we can do now,” he says, cranking the voltage up.
“Whoa, look at Snoopy now!” Phaneuf says, grinning. The detector registers two hundred thousand neutrons per second, then three hundred thousand—“and still climbing.”
“It’s really jamming!” Brinsmead shouts, watching Snoopy as Taylor nudges the power past thirty thousand volts.
“You’re getting eight hundred thousand neutrons per second,” Phaneuf says. “Nine hundred thousand now . . . a million!”
Brinsmead lets out a whoop as the neutron gauge tops out.
“Snoopy’s pegged!” he yells, doing a little dance. “Someone needs to turn up the range.”
Taylor makes a move for it, but Phaneuf grabs him lightly by the sleeve, stopping him. “Taylor, don’t go over there, no.” The stripped-away electrons hitting the chamber’s wall are emerging as x-rays. Phaneuf reaches out with the x-ray detector, takes a reading, and decides it’s worth the risk. He darts to the neutron detector and quickly dials up the range.
“Get away from that, Ron!” Brinsmead says, laughing as Phaneuf jumps back behind the protective wall of lead.
Taylor glances at the monitor, where the star in the center of the machine is now glowing so brightly that the surrounding grid has disappeared completely.
“Just a little more,” Taylor says under his breath as he nudges the voltage up, bringing the temperature of his reactor’s plasma core to an almost incomprehensible 580 million degrees—some forty times as hot as the core of the sun.
On the video screen, purple sparks fly away from the plasma cloud, illuminating the wonder in the faces of Phaneuf and Brinsmead, who stand in a half-orbit around Taylor. In the glow of the boy’s creation, the men suddenly look years younger.
Taylor keeps his thin fingers on the dial. As the atoms inside the fusor collide and fuse and throw off their energy—1.1 million neutrons per second, then 1.2 million—Taylor’s two mentors take a step back, shaking their heads and wearing ear-to-ear grins.
“There it is,” Taylor says, his eyes locked on the machine. “The birth of a star.”
Taylor powers down the fusor, then he and Phaneuf and Brinsmead emerge from behind the wall of lead. “Let’s see what Ricochet Rabbit has to say,” Brinsmead says, referring to the bubble detectors they’ve arranged around the fusor.
“A bubble detector cannot be fooled,” Phaneuf says as they walk toward the machine. “If you’ve got bubbles, it means you produced neutrons.”
They had bubbles.
Until that moment, Taylor had kept a lid on his emotions, at first concentrating on operating the reactor, and then concentrating on not declaring success prematurely. Now it was clear: Taylor Wilson had become the thirty-second person on the planet—and the youngest—to achieve nuclear fusion.
Taylor finally let himself go.
“We screamed and we shouted and we high-fived each other,” Taylor recalls.
“Taylor,” Phaneuf remembers, “was dancing on air.”
“We all were!” says Brinsmead. “To see the look on his face, after all that effort and trial and error and all we’d been through. Oh, man, that moment really made it worth it for me. And for Ron too—although I think we’d both enjoyed just about every minute of working with Taylor for the past several months. But now it was all really paying off. He’d done it!”
First, Taylor called his parents with the news. And then he called Willis, who was ecstatic.
The neutron output would increase as Taylor tweaked and optimized the machine over the next weeks, but the bubbles in the detector were proof positive that a nuclear reaction had occurred. They would restart the fusor and make several runs that day to accumulate a comprehensive data set documenting the achievement. Taylor took the data and the photos and videos home that night and sent the evidence to Fusor.net.
“I’d seen the kinds of questions that had been asked and the kinds of things that tripped people up in terms of neutron-detection methods,” says Taylor. “So we made sure we had rock-solid proof.” Taylor e-mailed video and still images and a full technical-data disclosure detailing the fusor’s setup, conditions, neutron-detection systems, and witnesses.
The Fusor.net community agreed that his proof was irrefutable: a nuclear fusion reaction had occurred. Once it was confirmed and verified, Richard Hull posted a message on the forum that the Neutron Club had a new member—the youngest fusioneer ever—and congratulations began pouring in from all over the world.
“I was pretty exc
ited,” Taylor remembers, “because it was a validation of what I’d set out to do. But I’d always been confident that I’d do it, so in a way it felt less like winning a gold medal and more like buying the [boxing] trunks to start training.
“It was a beginning. I had this tool now, and the world opened up. I could start playing with my neutrons and do all these experiments and find out all kinds of things. I had a whole world of questions, and now I had subatomic particles that I could use to start opening up the answers.”
At Davidson, word got around quickly: Taylor Wilson, the skinny, excitable kid with the crazy Southern accent, had created his own star. At first, few knew what to make of it.
“I was like, this is a metaphor, right, Taylor?” Ikya said.
“Not really,” Taylor said. “Stars are powered by nuclear fusion, and that’s what I made. It was hotter than the sun in there.” Words started to fly around the school—nuclear fusion, neutrons, ions, radiation—and Harsin fielded more calls from worried parents. Between the parades of students, professors, and administrators from Davidson and UNR who came through the lab to see his machine, Taylor continued to tweak it, experimenting with ways to increase its neutron output.
Over the next few weeks, he started using the fusor to irradiate different materials, bombarding them with neutrons to see how they would react. “I activated fifteen different elements with radiation,” he excitedly told Walenta, “and made atoms that had never existed on earth before.”
Taylor could have taken the fusor to the Western Nevada Regional Science Fair as it was and won. But he had higher ambitions. The fusor was a promising neutron source for research. But a conventional fusor emits too few neutrons for some applications, including Taylor’s medical-isotopes project. Taylor had an idea: He wanted to see if he could increase the neutron output by incorporating fissionable isotopes of heavy elements, using the neutrons from the fusion reactions to induce fission in the atoms of the heavy elements, which would produce more neutrons.