Particle physics is renowned for its huge — and expensive — experimental facilities. But a propensity to recycle equipment, whether large or small, is often overlooked. In one such example of frugality, an annullar electromagnet 50 feet in diameter is being transported from Brookhaven, on Long Island, New York, to be re-used in a new experiment at Fermilab, outside Chicago, Illinois. The 3,200-mile trip for the 1990s-built kit comes at a price that is just one tenth of the cost of building it anew.

The electromagnet, made of aluminium and steel, contains superconducting coils that cannot withstand damage. Hence the ring is to make a slow voyage, first by truck to Smith Point Marina on Long Island; then by barge down the east coast and up the Mississippi, Illinois and Des Plaines rivers. Finally, it will arrive, through rolling roadblocks on the back of a purpose-built truck, at Fermilab in July.

The electromagnet will still serve its original purpose as a storage ring for muons, but in the next generation of experiment to probe the anomalous magnetic moment of the muon. (Using the precession of the moment in a magnetic field it's possible to test for the influence of predicted, or unknown, particles that might be spontaneously created from the vacuum.)

The progress of the ring can be followed on a map at http://muon-g-2.fnal.gov/bigmove