Largest antimatter 'bottle' under construction -

While scientists have long been fascinated by antimatter, there's just one little problem in studying it - the moment it comes into contact with ordinary matter, it's annihilated in a burst of gamma radiation.

But a new 'trap' is under construction in San Diego which could allow trillions of positrons, the antimatter equivalent of electrons, and store them for hours.

It's now become routine to produce antimatter - the 'mirror image' of the ordinary matter in the observable universe - with radioisotopes and particle colliders.

Physicists can slow positrons from radioactive sources to low energy and accumulate and store them for days in specially designed 'bottles', whichm have walls made of magnetic and electric fields, rather than matter. They can cool them to temperatures as low as that of liquid helium, and compress them to high densities.

"One can then carefully push them out of the bottle in a thin stream, a beam, much like squeezing a tube of toothpaste," says Clifford Surko, a professor of physics at UC San Diego.

He and his colleagues are now building the world's largest trap for low-energy positrons, capable of storing vastly more antimatter than ever before.

"We are now working to accumulate trillions of positrons or more in a novel 'multi-cell' trap - an array of magnetic bottles akin to a hotel with many rooms, with each room containing tens of billions of antiparticles," he says.

He says that the creation of much larger bursts of positrons could enabling scientific research into substances such as antihydrogen and electron-positron plasmas like those believed to be present at the magnetic poles of neutron stars.

On a less pleasant note, it could eventually enable the creation of an annihilation gamma ray laser, says Surko.