By firing calcium isotopes into a plutonium target inside a particle accelerator, scientists at Lawrence Berkeley National Laboratory have finally confirmed the Russian discovery of the superheavy element 114.

It wasn't easy. It took more than a week of running the experiment to generate a measly two atoms of the stuff, which they reported in Physical Review Letters last week. It's basic science at the outer limits of matter.

"We're learning the limits of nuclei," said Ken Gregorich, a nuclear physicist at LBL. "How many protons can you pack into a nucleus before it falls apart?"

Uranium, which has 92 protons in its nucleus, is the heaviest element found in substantial quantities in nature. The first man-made "transuranic" elements like plutonium were discovered and synthesized during the 1940s in the run-up to the creation of nuclear weapons. Since then, it's gotten harder and harder to produce new elements, but scientists have kept at it. One reason is they hypothesized that certain isotopes of very heavy particles might exist in an "island of stability" that would allow them to stick around longer than the fractions of a second most synthetic elements last.

So, it was with great excitement that scientists received the news in early 1999 that the Joint Institute for Nuclear Research in Dubna appeared to have discovered Element 114 — and it lasted for whole seconds.

"It's fantastically important work," Neil Rowley of the Institute for Subatomic Research in Strasbourg, France told New Scientist in 1999.

Glenn Seaborg, Nobel Prize winner, adviser to presidents, and a big advocate of the island theory of superheavy elements, was even delivered the news of the Russian discovery on his death bed by an old friend.

"The term 'magic' was continually used — Seaborg and others spoke of a magic ridge, a magic mountain and a magic island of elements," wrote Oliver Sachs of the search for the island. "This vision came to haunt the imagination of physicists the world over. Whether or not it was scientifically important, it became psychologically imperative to reach, or at least to sight, this magic territory."

After decades of swimming through particle accelerator data, the island had been reached. It was tremendously big news.

Or so they thought.

As the years went by, the Russian team published a series of papers about Element 114, but other teams couldn't confirm their initial discovery of the extraordinarily long-lived particle. There were two reasons for this. One, the experimental apparatus required to check the findings were only available in a small number of labs around the world. Two, it appears the Russians were wrong.

"I think back in '99 they were learning how to do this and I think they had a random correlation of unrelated events that appeared to be Element 114," Gregorich said.

It's not that they didn't eventually discover Element 114. They did. It's just that their first observation, the most exciting one, turned out to be incorrect. In four separate publications from 2000 to 2004, they came up with better data, and those are the observations that Gregorich said his lab has confirmed.

And the island of stability? It is actually there, Gregorich said, but its effects are less pronounced than (at least) Seaborg hoped. The particular combinations of protons and neutrons do yield longer lasting elements, just not ... magic ones.

"Our results and the Dubna results show that there is some stability there," Gregorich said. "If we didn't have extra stability due to the shell effects, these things would decay faster than we could ever detect them with lifetimes on the order of 10-20 seconds rather than 10-1 seconds."

The search, though, for a more perfect superheavy element does go on.

"There are still predictions that if you could use more neutron-rich projectiles, if you could produce these elements but with more neutrons, some of them would be pretty long lived," he said.

Unfortunately, the particle accelerators in operation and currently planned won't reach the power necessary to get to create the theoretically most stable elements.

"The present and next generation of radioactive beam machines don't have high enough beam intensities," Gregorich said. "The technology doesn't exist today but it might in another 20 or 30 years."

Image: The Berkeley Gas-filled Separator, the detector used in the experiment, in situ.

Ken Gregorich/LBL.

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