A Magnet on the Move
Researchers transport a mammoth magnet thousands of miles over sea and land
Muon g-2’s journey spans 3,200 miles, with it first floating down the East Coast and then being transported to the outskirts of Chicago by truck. (Jim McMahon)
Earlier this summer, a team of scientists packed their bags for a wild road trip. The crew of researchers and movers are currently taking a humongous magnet on a 3,200-mile journey. The electromagnet, called Muon g-2 (pronounced “g minus two”), is basically a 50-foot-diameter metal ring. It magnetizes, or becomes attractive to other metals, when an electric current passes through it.
Muon g-2 has traveled by sea barge down the East Coast from Brookhaven National Laboratory on Long Island in New York. It has sailed around Florida and headed up several rivers toward Illinois. From there, it has been loaded onto a truck and is being driven to its destination—the Fermi National Accelerator Laboratory (also called Fermilab).
Fermilab, just outside Chicago, Illinois, has a particle accelerator that can produce muons—special negatively charged particles (extremely tiny objects) created after other particles collide. But the scientists at Fermilab still need an electromagnetic ring like Muon g-2 to store and measure these muons so they can study them.
Muons have unique properties that make them interesting to scientists. They rotate, or turn around, in a magnetic field. By studying the way muons move, scientists can possibly find evidence of new particles and learn more about how the universe works.
Moving Muon g-2 to Fermilab will cost an estimated $3 million. But this is still 10 times less than the cost of building a brand-new electromagnetic ring. Moving Muon g-2, however, is a challenge.
The team of researchers had thought about flying the electromagnet. But this might not have been very safe for people down below. "It turns out you can't just pick up a 15-ton ring and fly it over people's houses without asking them first," says Chris Polly, a lead scientist on the Muon g-2 project. So they put the metal ring on a barge on the ocean.
By transporting Muon g-2 mostly on the water, the moving team has avoided lots of the obstacles they would have found on land. But the scientists still needed to move the ring onto land to drive it the rest of the way to Fermilab. Transporting the massive ring to and from the barge required removing road signs and clipping trees.
Muon g-2 is currently mounted on a truck and travels at night, when there’s little traffic and sections of the road can be closed. Despite the darkness, the magnet’s journey doesn’t go unnoticed: Those in charge of the move have strung lights on the ring, attracting spectators to what looks like a giant saucer rolling down the streets.
“It’s not often our neighbors get a ringside seat for something this complex and interesting,” says Polly.